tag:theconversation.com,2011:/africa/topics/legionnaires-disease-1485/articlesLegionnaires’ disease – The Conversation2024-03-20T13:59:02Ztag:theconversation.com,2011:article/2261952024-03-20T13:59:02Z2024-03-20T13:59:02ZHot tubs are as full of nasty germs as you fear<figure><img src="https://images.theconversation.com/files/583080/original/file-20240320-24-y9bilo.jpg?ixlib=rb-1.1.0&rect=8%2C16%2C5601%2C3717&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/picture-showing-group-friends-enjoying-jacuzzi-769619995">Kamil Macniak/Shutterstock</a></span></figcaption></figure><p>A friend of mine recently lost her security deposit at the holiday home she and her fellow hens were renting for a weekend. Why? Well, she dropped a microwaveable lasagne into the hot tub. </p>
<p>Could happen to anyone.</p>
<p>Despite trying their hardest to sieve out all the bits of minced beef and curdled white sauce that bubbled up to the surface, it was all in vain. The damage was done. </p>
<p>A stray lasagne might be the least of your holiday hot tub worries, though. </p>
<p>There may be a host of other nasties lurking invisibly in the water. Despite the potential wellbeing benefits of heat and hydrotherapy, enjoying a relaxing dip in the hotel hot tub could do more harm than good. </p>
<h2>Hot tub lung</h2>
<p>For example, it’s possible to contract a respiratory condition, colloquially referred to as <a href="https://pubmed.ncbi.nlm.nih.gov/35857699/">hot-tub lung</a>. </p>
<p>It’s triggered by microbes called <a href="https://www.microbiologyresearch.org/content/mycobacteria"><em>mycobacteria</em></a>, from the same family as those which cause the infection tuberculosis (TB). </p>
<p>Like in TB, hot-tub lung bacteria generate patches of inflammation in the lung tissue. This results in symptoms such as shortness of breath, cough and fever. The lung changes can be seen on an X-ray or CT scan of the chest, and may appear quite profound. </p>
<p>The hot tub acts as a perfect environment for the growth of these bacteria because the warmth of the system creates an optimum temperature for their proliferation. The bubbling of the water also acts as an aerosol – allowing the bacteria to be released into the air, where they can be inhaled. </p>
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<p>Unlike TB, which requires long-term antibiotics and is becoming increasingly difficult to treat, hot tub lung may be considered more of an inflammatory condition. </p>
<p>Hot-tub lung was classified fairly recently, in comparison to other lung diseases, and was <a href="https://pubmed.ncbi.nlm.nih.gov/8996025/">first described in 1997</a>. It is more likely to be associated with frequent hot tubs users, or those with compromised immunity. </p>
<h2>Waterborne bugs</h2>
<p>There are many other organisms that can <a href="https://pubmed.ncbi.nlm.nih.gov/8855593/">flourish in hot-tub machinery</a>. </p>
<p>These include <em>legionella</em>, the bacteria which cause the potentially severe infective disorder, Legionnaire’s disease. </p>
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<p>Legionella’s breeding grounds are not just limited to hot tubs either. It is naturally found in fresh water and grows particularly well in water which is heated to warm temperatures. So, <a href="https://www.hse.gov.uk/legionnaires/what-is.htm">showers, swimming pools and air conditioning units</a> may also pose risks. </p>
<p>The symptoms of Legionnaire’s disease are much like those of other respiratory infections, including shortness of breath and a dry or phlegmy cough. But it’s common to get other complaints such as muscle aches and headaches too. Hospital treatment may be required, and antibiotics should be prescribed. </p>
<p>It’s not just the lungs that can be affected by water-borne bacteria. Bacteria in hot tubs can trigger <a href="https://www.medicalnewstoday.com/articles/324721">infections of the skin</a>, such as hot tub folliculitis, which may occur in <a href="https://pubmed.ncbi.nlm.nih.gov/33123436/">outbreak clusters</a>. </p>
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<p>Hot tubs can also trigger infections in the eye, particularly if <a href="https://www.healthline.com/health/can-you-swim-with-contacts">wearing contact lenses</a>. So it’s advisable to remove them before getting in. </p>
<h2>Reaping the benefits</h2>
<p>If you avoid the bacteria, hot tubs may have some positive effects on health and wellbeing. </p>
<p>It’s possible, for example, that heat therapy could generate the production of so-called <a href="https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/heat-shock-protein">“heat-shock” proteins</a>, which have the ability to impact metabolism. Human trials have found that these proteins could influence the body’s sensitivity to insulin and the laying down of fatty tissue, therefore acting as natural treatments for <a href="https://pubmed.ncbi.nlm.nih.gov/26049635/">diabetes and obesity</a>. </p>
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<p>The potentially restorative properties of simple immersion in water, both heated or cooled, are well documented. Water acts as a medium to deliver either heat, but also cold temperatures, sometimes to the extreme. </p>
<p><a href="https://physoc.onlinelibrary.wiley.com/doi/10.1113/EP086283">Cold water immersion (CWI)</a> has garnered a lot of attention, and purpose built cold tubs are making more appearances. Alongside potential benefits – including rapid healing and recovery, mood enhancement and improved immunity – are grave risks. These can include drowning and fatal cardiac arrhythmias, triggered by the extreme cold. There’s no medical consensus, however, on whether CWI’s benefits outweigh its risks.</p>
<p>Exercising in water, the branch of alternative medicine known as hydrotherapy, has been proposed as a holistic technique to treat a myriad of conditions. These range from <a href="https://pubmed.ncbi.nlm.nih.gov/37438576/">high blood pressure</a> to <a href="https://pubmed.ncbi.nlm.nih.gov/35171330/">cancer</a>. While the jury is still out on the overall effectiveness of this method, some patients have reported improved energy levels and mood, as well as reduced anxiety and pain. </p>
<p>So, the next time you’re thinking of retiring to the hot tub with a glass of champagne, consider what you might be stepping into. </p>
<p>Make sure, at least, that the tub has been properly maintained and cleaned. But be aware that chlorine <a href="https://www.mdpi.com/2076-2607/8/12/2026">doesn’t kill all</a> the nasty stuff like <em>legionella</em>. </p>
<p>Whatever you do, make sure you pop out your contact lenses – and never, ever take a lasagne into a hot tub.</p><img src="https://counter.theconversation.com/content/226195/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dan Baumgardt does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Hot tubs may offer welcome stress relief – but be aware of what you might be stepping intoDan Baumgardt, Senior Lecturer, School of Physiology, Pharmacology and Neuroscience, University of BristolLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1777462022-03-02T18:40:59Z2022-03-02T18:40:59ZFuture infectious diseases: Recent history shows we can never again be complacent about pathogens<figure><img src="https://images.theconversation.com/files/449127/original/file-20220301-23-k3vb1g.jpg?ixlib=rb-1.1.0&rect=536%2C0%2C2189%2C1331&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">COVID-19 will not be the last infectious disease event of our time. We need to prepare for the next challenge with evidence and knowledge.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>As we move into the third year of the global pandemic caused by COVID-19, it’s important to ask what we have learned and what we have done to prepare for the next infectious-disease crisis.</p>
<p>It could be an outbreak of Lyme disease, an epidemic of measles or another full-blown global pandemic of influenza or coronavirus. It could be a threat that emerges from the ongoing challenge of <a href="https://www.cdc.gov/drugresistance/about.html#:%7E:text=Antibiotic%20resistance%20happens%20when%20germs,in%20the%20U.S.%20each%20year.">antimicrobial resistance</a> and the steadily fading power of established antibiotics.</p>
<p>One thing is certain: COVID-19 will not be the last challenge of our time, and even while we are striving to tame the current pandemic, we need to prepare for the next challenge, using evidence and knowledge.</p>
<h2>Infectious diseases</h2>
<p>For most of human history, <a href="https://doi.org/10.1001/jama.281.1.61">infectious diseases have been the leading cause of death</a>, preying mainly on the very young, the old and the most vulnerable among us.</p>
<p>Scientific advancements in the 20th century reversed this historical trend — at least for a time.</p>
<p>Our ability to control infection through <a href="https://doi.org/10.1146/annurev.publhealth.20.1.0">public health measures</a> such as clean water and by developing vaccines, antibiotics, antiviral and antiparasitic agents has changed the way we live — and the way we die.</p>
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<a href="https://images.theconversation.com/files/448861/original/file-20220228-25-127fpd2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Old illustration of a large room with a row of patients in beds and nurses looking after them" src="https://images.theconversation.com/files/448861/original/file-20220228-25-127fpd2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/448861/original/file-20220228-25-127fpd2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=489&fit=crop&dpr=1 600w, https://images.theconversation.com/files/448861/original/file-20220228-25-127fpd2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=489&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/448861/original/file-20220228-25-127fpd2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=489&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/448861/original/file-20220228-25-127fpd2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=614&fit=crop&dpr=1 754w, https://images.theconversation.com/files/448861/original/file-20220228-25-127fpd2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=614&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/448861/original/file-20220228-25-127fpd2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=614&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">For most of human history, infectious diseases have been the leading cause of death.</span>
<span class="attribution"><span class="source">Hampstead Smallpox Hospital, London. Wellcome Collection.</span></span>
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<p>Statistics Canada data show that controlling infectious diseases has bought us more than <a href="https://www150.statcan.gc.ca/n1/pub/11-630-x/11-630-x2016002-eng.htm">two decades of extra life</a>, on average. It’s a remarkable achievement, and as a result, diseases of aging — <a href="https://www150.statcan.gc.ca/n1/daily-quotidien/201126/t001b-eng.htm">cancer, cardiovascular illness, chronic ailments, and degenerative neurological diseases such as Alzheimer’s</a> — are now the major causes of death. </p>
<p>What we should have learned over the last few decades, however, is that our control over infection is illusory and that we remain vulnerable. </p>
<p>The 1970s saw the emergence of <a href="https://www.cdc.gov/flu/swineflu/keyfacts_pigs.htm">swine flu</a> and <a href="https://www.cdc.gov/legionella/about/history.html#:%7E:text=Legionella%20was%20discovered%20after%20an,became%20known%20as%20Legionnaires'%20disease.">Legionnaire’s disease</a>. The ‘80s brought <a href="https://www.who.int/news-room/fact-sheets/detail/hiv-aids">HIV/AIDS</a>, the '90s witnessed <a href="https://www.who.int/health-topics/ebola/#tab=tab_1">Ebola</a> and the early 2000s brought the return of <a href="https://www.who.int/emergencies/situations/influenza-a-(h1n1)-outbreak">influenza with H1N1</a>, the <a href="https://www.who.int/health-topics/severe-acute-respiratory-syndrome#tab=tab_1">first SARS crisis</a> and <a href="https://www.who.int/health-topics/middle-east-respiratory-syndrome-coronavirus-mers#tab=tab_1">Middle East respiratory syndrome (MERS)</a>. </p>
<p>During that same period, the pharmaceutical industry <a href="https://doi.org/10.1038/d41586-020-02884-3">put antibiotic discovery on the back burner</a>, favouring the invention of more profitable treatments for chronic diseases, with their endlessly renewable prescriptions.</p>
<p>Without alternatives to penicillin, <a href="https://doi.org/10.1016/S0140-6736(22)00087-3">antimicrobial resistance has become, like climate change, a slow-moving but inexorably advancing global crisis</a>.</p>
<h2>Infection control</h2>
<p>The current pandemic has forced governments, public health officials and the health-care sector overall into a prolonged emergency footing, showing us very clearly that we cannot take infection control for granted.</p>
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<span class="caption">The COVID-19 pandemic has made it clear that infection control cannot be taken for granted.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<p>At the same time, we have been able to benefit from ongoing advancements in fundamental research and development. These advancements have enabled swift response to the current crisis with <a href="https://www.nytimes.com/interactive/2021/world/covid-vaccinations-tracker.html">multiple vaccine platforms</a>, <a href="https://dx.doi.org/10.1016%2FS1473-3099(21)00048-7">do-it-yourself diagnostic tests</a> featuring unprecedented sensitivity, <a href="https://www.nytimes.com/interactive/2020/science/coronavirus-drugs-treatments.html">new antiviral drugs and antibodies</a>, and the real-time production of robust evidence and information to keep pace with every turn in the pandemic saga.</p>
<p>Information technology has developed with amazing speed, providing the opportunity to disseminate critical information instantly. The <a href="https://doi.org/10.1038/s41586-020-2008-3">complete genome sequence of SARS-CoV-2</a>, for example, was available to researchers across the globe well before the COVID-19 virus arrived on their doorsteps. </p>
<p>Still, this same technology has also <a href="https://toronto.ctvnews.ca/misinformation-on-social-media-linked-to-higher-spread-of-covid-19-in-new-study-1.5466846">provided a platform for those who would discredit these scientific advances</a>, oppose public health sector leaders, and even interfere with front-line workers caring for patients.</p>
<h2>One Health</h2>
<p>Infectious diseases are almost always what we call <a href="https://www.cdc.gov/onehealth/basics/index.html">One Health</a> problems. The term refers to the intimate link between human and animal health, agriculture and the environment. </p>
<p>Microbes that cause disease often move easily between reservoirs in the environment, animals and people. Human encroachment into previously remote regions continues at an alarming rate, <a href="https://doi.org/10.1186/s40101-020-00239-5">exposing us to previously isolated viruses, bacteria and parasites</a>.</p>
<p><a href="https://www.canada.ca/en/public-health/services/reports-publications/canada-communicable-disease-report-ccdr/monthly-issue/2019-45/issue-5-may-2-2019/article-5-observatory-climate-change-adaptation-quebec.html">Climate change is creating new vectors to spread these diseases</a>, such as ticks and mosquitoes migrating into newly warmed environments.</p>
<p>As climate change continues and the demand for nutrition grows, strains on the environment will generate new infection challenges. Seeing three unique, novel coronaviruses (SARS, MERS and SARS-CoV-2) jump from environmental reservoirs into humans in the space of a two decades should have spurred us to be vigilant, alert and prepared, yet we still aren’t ready enough. </p>
<h2>Complacency</h2>
<p><a href="https://www.cbc.ca/news/politics/auditor-general-pandemic-covid-phac-1.5963895">Public-health</a> <a href="https://doi.org/10.17269/s41997-020-00342-1">infrastructure</a>, research into <a href="https://www.universityaffairs.ca/news/news-article/massive-investments-needed-now-to-avoid-next-pandemic/">infectious diseases</a> and the development of new therapies have been neglected for decades.</p>
<p>Before the pandemic, our increased lifespans and ability to neutralize some infections with preventions and treatments had lulled us into complacency regarding the infectious diseases we had once rightly feared. </p>
<p>With such easily accessible global travel and a standard of living that relies on international trade, turning back the clock is impossible. </p>
<p>We must anticipate and <a href="https://www.youtube.com/watch?v=DQtoi-n_K9Y">prepare for more outbreaks</a>, <a href="https://www.statnews.com/2021/05/18/luck-is-not-a-strategy-the-world-needs-to-start-preparing-now-for-the-next-pandemic/">epidemics</a> and <a href="https://www.gavi.org/vaccineswork/next-pandemic">pandemics</a>. </p>
<p>We need to establish robust research networks and be able to mobilize them quickly <a href="https://www.ctvnews.ca/health/the-world-is-unprepared-for-the-next-pandemic-study-finds-1.5699732">when new problems emerge</a>.</p>
<p>We need to invest in <a href="https://theconversation.com/the-roots-of-canadas-covid-19-vaccine-shortage-go-back-decades-154792">biomedical and biomanufacturing infrastructure</a> that can respond urgently to these challenges enabling us to <a href="https://edmontonjournal.com/news/postpandemic/post-pandemic-how-has-covid-19-changed-the-way-canada-thinks-about-and-studies-vaccines">rapidly produce new vaccines and drugs</a>. </p>
<p>If we do not invest continuously in these platforms, we will doom ourselves to still more crises that we could have anticipated and prevented.</p><img src="https://counter.theconversation.com/content/177746/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Gerry Wright consults and owns shares in Prokaryotics, an antibiotic discovery company. </span></em></p>Before COVID-19, clean water, antibiotics and vaccines had made us complacent about infectious disease. Infection control can no longer be taken for granted. We must be prepared for future pandemics.Gerry Wright, Professor of Biochemistry and Biomedical Sciences, McMaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1443222020-09-08T12:17:39Z2020-09-08T12:17:39ZDangerous bacteria is showing up in school water systems, reminding all buildings closed for COVID-19 to check the pipes<figure><img src="https://images.theconversation.com/files/356686/original/file-20200907-24-1mi2rrl.jpeg?ixlib=rb-1.1.0&rect=0%2C105%2C2923%2C1846&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Schools in Ohio and Pennsylvania have already found Legionella, the bacteria that causes Legionnaires' disease, in their water systems.</span> <span class="attribution"><a class="source" href="https://engineering.purdue.edu/PlumbingSafety">Andrew Whelton/Purdue University</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>As schools cautiously reopen for the fall semester, several have discovered potentially harmful bacteria in their water systems. Parents are likely concerned about what this means for their children, and other districts may be checking their own water’s safety.</p>
<p>As researchers who investigate water quality in buildings, we <a href="https://theconversation.com/the-coronavirus-pandemic-might-make-buildings-sick-too-136373">warned</a> earlier this year that the pandemic stay-at-home orders could allow bacteria and harmful metals to accumulate in water as it <a href="http://doi.org/10.1002/aws2.1186">sat unused in buildings’ pipes</a>. </p>
<p>Some building managers looked for those problems as they reopened and found them. More than 10 schools in <a href="https://www.whio.com/news/three-dayton-public-school-buildings-test-positive-legionella-bacteria/CQMON2WWWVGUXBC42NQD4SRB3U/">Ohio</a> and <a href="https://www.msn.com/en-us/news/us/elevated-levels-of-legionella-found-in-water-pipes-at-oblock-junior-high-school/ar-BB18HhqI">Pennsylvania</a> have <a href="https://www.nytimes.com/2020/08/27/health/covid-schools-legionnaires-disease.html">reported</a> finding harmful bacteria in their plumbing. Even the Centers for Disease Control and Prevention, the nation’s health protection agency, <a href="https://www.nytimes.com/2020/08/08/health/cdc-legionnaires-coronavirus.html">discovered Legionella, the bacteria that causes Legionnaires’ disease, in buildings</a> it leases.</p>
<p>This presents potential health risks. For schools, it means the long checklist for maintaining a safe learning environment should include water systems. Luckily, there are simple steps that can minimize the risks.</p>
<h2>Schools – it’s time to learn about water safety</h2>
<p>Most schools our team interacts with do not check or flush their water pipes regularly. During school breaks, water often sits in their plumbing for days, weeks or months. This has been even longer during the pandemic.</p>
<p>When water use is low or has stopped, the water stagnates. That can allow organisms like Legionella to grow and harmful metals to leach into the water, potentially making it unsafe to drink or use. </p>
<p>Some school buildings have more than 300 water use locations, such as gym showers, water fountains and sinks in classrooms, kitchens and restrooms. Many locations go unused for long periods of time, even when school is in session. Large buildings can also have underlying problems with water temperature and movement that allow growth even without stagnation.</p>
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<img alt="A biofilm cross-section of Legionella in a water pipe." src="https://images.theconversation.com/files/352322/original/file-20200811-20-15b4sii.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/352322/original/file-20200811-20-15b4sii.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=375&fit=crop&dpr=1 600w, https://images.theconversation.com/files/352322/original/file-20200811-20-15b4sii.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=375&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/352322/original/file-20200811-20-15b4sii.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=375&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/352322/original/file-20200811-20-15b4sii.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=471&fit=crop&dpr=1 754w, https://images.theconversation.com/files/352322/original/file-20200811-20-15b4sii.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=471&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/352322/original/file-20200811-20-15b4sii.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=471&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="attribution"><a class="source" href="https://www.nist.gov/news-events/news/2020/05/nist-identifies-critical-needs-improved-plumbing">B. Hayes/NIST</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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</figure>
<p>There are no federal requirements for <a href="https://www.epa.gov/dwreginfo/lead-drinking-water-schools-and-childcare-facilities">most schools</a> to test their drinking water. Any testing for Legionella is voluntary, and there are no nationally regarded <a href="https://www.ncbi.nlm.nih.gov/books/NBK555112/">amounts of Legionella for when to take action</a>, even if schools did test. Testing for other contaminants like metals varies by <a href="https://environmentamerica.org/sites/environment/files/reports/GetTheLeadOut_032119.pdf">state</a> and is generally not required, unless the school itself is declared a public water system. </p>
<h2>Who is at risk?</h2>
<p>It’s well-known that <a href="http://doi.org/10.3390/pathogens4020373">harmful organisms</a> can grow in pipes and devices like <a href="http://doi.org/10.1128/AEM.52.3.434-438.1986">filters</a>, <a href="https://doi.org/10.1186/s40168-015-0134-1">heaters</a> and <a href="https://www.cdc.gov/healthywater/other/industrial/cooling_towers.html">cooling towers</a>. Finding Legionella in both cold and hot water systems is not that surprising.</p>
<p>We do not know if Legionella was present before the pandemic. It may have been there last summer. It may be there again next summer, too. <a href="https://www.baltimoresun.com/maryland/howard/cng-ho-schools-bacteria-testing-1018-20191018-e2wxgomcevfilawhghmdy2puyq-story.html">Multiple</a> <a href="https://www.nbc12.com/2019/09/24/chesterfield-creates-legionella-information-website/">schools</a> have <a href="https://www.woboe.org/site/default.aspx?PageType=3&DomainID=4&ModuleInstanceID=22&ViewID=6446EE88-D30C-497E-9316-3F8874B3E108&RenderLoc=0&FlexDataID=9986&PageID=1">dealt</a> with Legionella in <a href="https://www.chicagotribune.com/suburbs/post-tribune/ct-ptb-chesterton-legionnaires-report-st-1012-20191011-7b6kyqjhkzbi3gqh7jrqozbcga-story.html">recent</a> <a href="https://www.cnn.com/2015/09/23/health/legionnaires-disease-schools-closed/index.html">years</a>. In Ohio schools, Legionella testing seems to have been influenced by numerous pandemic-related <a href="https://epa.ohio.gov/Portals/28/documents/pws/ODH-OhioEPA-Building-Owners-Occupants-Tenants.pdf">water</a> <a href="https://odh.ohio.gov/wps/portal/gov/odh/know-our-programs/Legionella-Environmental/welcome/">warnings</a>, as well as a Legionnaires’ disease case and possible link to a <a href="https://www.daytondailynews.com/news/local-education/2019-kettering-fairmont-custodian-death-also-linked-legionella/yRLc6IqPZdBl1r75jx7wDI/">janitor’s death</a> at the same school one year earlier.</p>
<p>Most children are not in a <a href="https://www.cdc.gov/legionella/about/causes-transmission.html#risk">high-risk group</a> for Legionnaires’ disease, a pneumonia-like respiratory illness, but faculty, staff and children with weakened immune systems may be. It is also unknown how many children might get a less severe disease from Legionella called <a href="https://www.cdc.gov/legionella/about/signs-symptoms.html#pontiac">Pontiac fever</a>, which has flu-like symptoms. </p>
<p>Infections are often linked to inhalation of aerosols when water splashes, like in showers or hot tubs, but also when <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4666014/">flushing toilets</a> or <a href="https://pubmed.ncbi.nlm.nih.gov/1909134/">washing hands</a>.</p>
<h2>Metals like lead and copper also pose risks</h2>
<p>Other health risks may also be building in school pipes. Exposure to lead, which can leach from metal plumbing materials, has been linked to <a href="https://www.epa.gov/ground-water-and-drinking-water/basic-information-about-lead-drinking-water">learning disabilities and cardiovascular effects</a>. Copper leaching from metal plumbing materials can cause acute illnesses like <a href="https://www.nap.edu/read/9782/chapter/8#130">nausea and diarrhea</a>.</p>
<p>A <a href="https://pubs.rsc.org/en/content/articlelanding/2020/ew/d0ew00520g/unauth#!divAbstract">new study</a> describes widespread copper contamination in an Indiana school just seven years after it was built. The only reason problems were detected was because the school decided to test – it wasn’t required to do so.</p>
<p>Also problematic are other metals like manganese, nickel and zinc. In schools, we’re finding levels of these metals exceeding acute drinking water exposure limits. </p>
<p>Plumbing isn’t necessarily safe just because it’s built to code.</p>
<h2>Keeping students and teachers safe</h2>
<p>Schools should assess water safety every summer before students and staff return to the buildings. </p>
<p>All schools should have an active <a href="https://www.cdc.gov/legionella/wmp/toolkit/index.html">water management program</a>. These programs should address chemical and biological hazards, as well as schools’ dramatic fluctuations in use during the year. </p>
<p>Educating parents, students and staff about the risks is also important. While <a href="https://www.k-state.edu/today/announcement/?id=65406">shutting down water fountains</a> decreases <a href="https://www.huffpost.com/entry/safe-drink-water-fountain-covid-19_l_5f354030c5b6fc009a629713">touchpoints where the coronavirus could spread</a>, students and staff should not turn to water outlets that are not approved for drinking. Sports team containers should not be filled at the shower. Hot water systems do not have to undergo rigorous testing that potable cold water systems must pass.</p>
<figure class="align-center ">
<img alt="A school restroom sink with a sign warning not to drink the water." src="https://images.theconversation.com/files/356831/original/file-20200907-20-zrzkoa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/356831/original/file-20200907-20-zrzkoa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=494&fit=crop&dpr=1 600w, https://images.theconversation.com/files/356831/original/file-20200907-20-zrzkoa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=494&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/356831/original/file-20200907-20-zrzkoa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=494&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/356831/original/file-20200907-20-zrzkoa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=621&fit=crop&dpr=1 754w, https://images.theconversation.com/files/356831/original/file-20200907-20-zrzkoa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=621&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/356831/original/file-20200907-20-zrzkoa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=621&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Bacteria can be transmitted by aerosols when water splashes while showering, flushing toilets or washing hands.</span>
<span class="attribution"><a class="source" href="https://engineering.purdue.edu/PlumbingSafety">Andrew Whelton/Purdue University</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Water management programs can identify regular preemptive actions like flushing water systems before school begins. <a href="https://www.youtube.com/watch?v=LVwRsTnj63g&feature=y1778946100.1585943145-1886711419.1568850380">Flushing</a> can help bring chemical disinfectant residual to every tap to limit growth. Inexpensive hand-held disinfectant meters and thermometers can enable building operators to do their own testing. This testing could be more useful for understanding and managing water system problems than spot-testing for bacteria alone. </p>
<p>When flushing isn’t enough, schools may need more extreme procedures. These include chemically “shocking” the plumbing, replacing fixtures or installing building water treatment. It’s important to remember that “shocking” is sometimes just a short-term fix, as <a href="http://doi.org/10.2166/WST.2005.0216">harmful organisms can return</a> if not eradicated. A long-term commitment to healthy plumbing is needed.</p>
<p>[<em>Deep knowledge, daily.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=deepknowledge">Sign up for The Conversation’s newsletter</a>.]</p>
<p>The pandemic is an opportunity for schools to better understand their water systems so they can protect their students, teachers and staff. Education and preemptive action can help prevent children from getting sick, at least from the water.</p><img src="https://counter.theconversation.com/content/144322/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Caitlin R. Proctor receives funding from the US National Science Foundation, US Environmental Protection Agency, and Purdue University.</span></em></p><p class="fine-print"><em><span>Andrew J. Whelton receives funding from the US National Science Foundation, Paradise Irrigation District, US Environmental Protection Agency, and Paradise Rotary Foundation. </span></em></p>When water stagnates in pipes, harmful metals and bacteria can accumulate and make people sick. Buildings that were shut down for weeks during the pandemic may be at risk.Caitlin R. Proctor, Lillian Gilbreth Postdoctoral Fellow, Purdue UniversityAndrew J. Whelton, Associate Professor of Civil, Environmental & Ecological Engineering, Purdue UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1390592020-06-04T11:18:55Z2020-06-04T11:18:55ZAfter coronavirus, another hidden respiratory disease lurks in the buildings we left behind<figure><img src="https://images.theconversation.com/files/339276/original/file-20200602-133910-1mky30d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/view-old-buildings-water-towers-midtown-1280896291">Charlotte Raboff/Shutterstock</a></span></figcaption></figure><p>Global outbreaks of coronavirus have forced the closing of schools, gyms, offices and other buildings at a scale never seen before. Now, as countries start reopening after lockdown, those previously abandoned buildings could have become a breeding ground for another infection – Legionnaires’ disease.</p>
<p>Legionnaires’ disease is caused by inhaling water droplets that contain the <em>Legionella pneumophilia</em> bacteria. It’s quite rare, but the long periods of inactivity in buildings during lockdown greatly increases the risk of outbreaks. </p>
<h2>What is Legionnaires’ disease?</h2>
<p>Legionnaires’ disease causes severe pneumonia. In fact its <a href="https://www.cdc.gov/legionella/about/signs-symptoms.html">symptoms</a> could easily be mistaken for COVID-19. They include fever, dry cough, shortness of breath and muscle pain. This means the potential for increased incidence of Legionnaires’ due to missed diagnosis cannot be overstated. </p>
<p>Unlike COVID-19, Legionnaires’ does not spread from person to person but causes <a href="https://www.ncbi.nlm.nih.gov/pubmed/28141970">large community outbreaks</a> through contaminated airborne water droplets from sources including showerheads, taps, cooling towers, air-conditioning systems, spa pools, hot tubs and water fountains.</p>
<p>The disease can be deadly, and infects multiple people at once. A recent outbreak in North Carolina saw <a href="https://www.npr.org/2019/10/04/767210215/n-c-officials-trace-124-legionnaires-disease-cases-to-hot-tub-at-a-fair">124 people</a> contract the disease and <a href="https://www.buzzfeednews.com/article/olivianiland/hot-tub-north-carolina-legionnaires-disease-outbreak">four people die</a> after walking past a infected hot tub display.</p>
<p>The bacteria live in warm environments, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3856027/">surviving in biofilm</a> – clusters of microbial life that gather on surfaces – and feeding on pipework sludge and sediment. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/336523/original/file-20200520-152302-54g3sl.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/336523/original/file-20200520-152302-54g3sl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/336523/original/file-20200520-152302-54g3sl.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=326&fit=crop&dpr=1 600w, https://images.theconversation.com/files/336523/original/file-20200520-152302-54g3sl.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=326&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/336523/original/file-20200520-152302-54g3sl.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=326&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/336523/original/file-20200520-152302-54g3sl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=410&fit=crop&dpr=1 754w, https://images.theconversation.com/files/336523/original/file-20200520-152302-54g3sl.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=410&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/336523/original/file-20200520-152302-54g3sl.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=410&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Factors that lead to Legionella growth in biofilm,</span>
<span class="attribution"><a class="source" href="https://www.cdc.gov/legionella/wmp/overview/growth-and-spread.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Flegionella%2Fwater-system-maintenance%2Fgrowth-and-spread.html">CDC</a></span>
</figcaption>
</figure>
<p>All water systems are at risk of this foreseeable and preventable contamination, but dormant and decommissioned buildings are especially at risk. That’s because intermittent use of buildings and equipment and the interruption of cleaning regimes increase the likelihood of water stagnation, which in turn increases the likelihood of a <em>Legionella</em> outbreak. </p>
<h2>What is the risk?</h2>
<p>The end of lockdown could not come at a worse time for potential Legionnaires’ outbreaks. The <em>Legionella</em> bacteria <a href="https://www.ecdc.europa.eu/en/publications-data/figure-2-number-legionnaires-disease-cases-month-eueea-2011-2014-0">flourishes</a> in summer months, as the optimum range for the bacteria is between 20-45°C. </p>
<p>Even more worryingly, countries that have had some of the most stringent lockdowns – and which as a result will have large numbers of disused buildings – are the countries where this disease is most common. France, Germany, Italy, Spain, the UK and Netherlands accounted for 70% of all <a href="https://www.ecdc.europa.eu/en/publications-data/legionnaires-disease-annual-epidemiological-report-2017">cases reported in Europe</a> in 2017. Of those, 10-15% of cases report a fatal outcome. </p>
<p>Meanwhile, the US, which has had widespread lockdowns, has experienced an <a href="https://aem.asm.org/content/early/2019/09/09/AEM.01776-19/article-info?versioned=true">800% increase</a> in reported cases over the past 20 years, probably because environmental impacts such as increased rainfall and warmer temperatures benefit the growth of <em>Legionella</em>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/336521/original/file-20200520-152311-1iankje.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/336521/original/file-20200520-152311-1iankje.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/336521/original/file-20200520-152311-1iankje.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=461&fit=crop&dpr=1 600w, https://images.theconversation.com/files/336521/original/file-20200520-152311-1iankje.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=461&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/336521/original/file-20200520-152311-1iankje.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=461&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/336521/original/file-20200520-152311-1iankje.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=579&fit=crop&dpr=1 754w, https://images.theconversation.com/files/336521/original/file-20200520-152311-1iankje.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=579&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/336521/original/file-20200520-152311-1iankje.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=579&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Distribution of Legionnaires’ disease cases in the EU/EEA, 2016.</span>
<span class="attribution"><a class="source" href="https://www.ecdc.europa.eu/sites/default/files/documents/AER_for_2017-Legionnaires-disease_1.pdf">European Centre for Disease Prevention and Control</a></span>
</figcaption>
</figure>
<p>As well as the risk in public buildings, there is also potential for increased domestic exposure as a result of the coronavirus pandemic. </p>
<p>Consumer buying trends report hot tub sales are surging – one online seller reported a <a href="https://www.businesscloud.co.uk/news/online-hot-tub-business-sees-1600-uk-surge-during-lockdown">1600% increase</a> in demand during lockdown. As the North Carolina example shows, hot tubs can become a breeding ground for Legionnaires’ when they are not cleaned or disinfected properly. </p>
<h2>COVID-19 vs Legionnaires’ disease</h2>
<p><a href="https://wwwnc.cdc.gov/eid/article/20/11/13-1872_article">At-risk groups</a> for Legionnaires’ disease are largely the same as for COVID-19 – 90% of cases affect people over 45, and two-thirds are male. Having chronic lung disease and other illnesses such as diabetes increases your risk of severe illness from Legionnaires’ disease, just as it does for COVID-19. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/339278/original/file-20200602-133919-1oiepng.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/339278/original/file-20200602-133919-1oiepng.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/339278/original/file-20200602-133919-1oiepng.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=776&fit=crop&dpr=1 600w, https://images.theconversation.com/files/339278/original/file-20200602-133919-1oiepng.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=776&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/339278/original/file-20200602-133919-1oiepng.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=776&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/339278/original/file-20200602-133919-1oiepng.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=976&fit=crop&dpr=1 754w, https://images.theconversation.com/files/339278/original/file-20200602-133919-1oiepng.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=976&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/339278/original/file-20200602-133919-1oiepng.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=976&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Legionella pneumophila bacterium causes the majority of Legionnaires’ disease outbreaks.</span>
<span class="attribution"><a class="source" href="https://www.cdc.gov/legionella/images/materials-illustration.jpg">CDC</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-sa/4.0/">CC BY-NC-SA</a></span>
</figcaption>
</figure>
<p>But the strategy for fighting COVID-19 is not the one to adopt for Legionnaires’ disease. </p>
<p>People suspected of illness with COVID-19 are typically asked to self-isolate for a period of 14 days to prevent passing on the disease to others. But Legionnaires’ disease cannot be passed from person to person, and the symptoms worsen significantly over a seven-day period. As Legionnaires’ is caused by a bacteria, prompt treatment with antibiotics is vital. Delaying treatment can result in severe respiratory failure. </p>
<p>The additional risk of Legionnaires’ disease to recovered COVID-19 patients is currently unknown. <a href="https://www.medrxiv.org/content/10.1101/2020.02.29.20027698v2">Pre-print studies</a> of coronavirus cases in China and Japan found that 20% of COVID-19 patients were also infected with the <em>Legionella</em> bacteria. So it seems that coronavirus patients are more vulnerable to other community-acquired infections such as a Legionnaires’ and are at risk of acquiring it in hospital, as it can easily breed in medical facilities and equipment.</p>
<p>In the coming months as countries re-open, negative test results for coronavirus in those presenting with influenza and severe respiratory symptoms should be immediately referred for Legionnaires’ disease testing and not simply encouraged to recuperate alone. This could have a major impact on survival and recovery rates.</p>
<h2>How your employer should keep you safe</h2>
<p><em>Legionella</em> can rapidly become a public health problem in everyday places such as offices, schools, colleges, <a href="https://www.gov.uk/government/collections/legionnaires-disease-guidance-data-and-analysis">healthcare settings</a>, and factories. Employers are legally required to protect worker health from <em>Legionella</em> infection in <a href="http://www.bohs.org/return-to-work-guidance/">most jurisdictions</a>. </p>
<p>As countries exit lockdown, a comprehensive assessment must be made of all water systems in premises before anyone returns to work. <a href="https://www.hse.gov.uk/healthservices/legionella.htm">Effective water management programmes</a> in buildings, facilities and plant will eliminate this public health threat. </p>
<p>Increasing commercial and public awareness of <em>Legionella</em> controls is critical in long-term disease prevention. National and local publicity on Legionnaires’ disease risks when returning to work and leisure, along with guidance on the <a href="https://www.cieh.org/media/4208/legionella-guidance-covid-19.pdf">safe re-opening of buildings</a> should help to reduce the likelihood of disease outbreaks.</p><img src="https://counter.theconversation.com/content/139059/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Anne Clayson does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>It causes fever, a dry cough, shortness of breath. Outbreaks are frequently deadly. It’s not COVID-19, and it could be waiting in your workplace after lockdown.Anne Clayson, Programme Director, Associate Professor in Occupational Hygiene and Occupational Health, University of ManchesterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1363732020-04-21T12:46:23Z2020-04-21T12:46:23ZThe coronavirus pandemic might make buildings sick, too<figure><img src="https://images.theconversation.com/files/328922/original/file-20200419-152581-149lj0p.jpg?ixlib=rb-1.1.0&rect=0%2C660%2C3010%2C2313&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Discolored water can be caused by heavy metals, such as iron or copper. Iron can also act as a nutrient for organisms to grow in the pipes.</span> <span class="attribution"><a class="source" href="https://engineering.purdue.edu/PlumbingSafety?_ga=2.123591374.457264888.1587310129-1396667686.1586369641">Kyungyeon Ra/Purdue University</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>While millions of people are under orders to stay home amid the coronavirus pandemic, water is sitting in the pipes of empty office buildings and gyms, getting old and potentially dangerous.</p>
<p>When water isn’t flowing, organisms and chemicals can build up in the plumbing. It can happen in underused gyms, office buildings, schools, shopping malls and other facilities. These organisms and chemicals can reach unsafe levels when water sits in water pipes for just a few days. But, what happens when water sits for weeks or months?</p>
<p>There are <a href="https://www.doi.org/10.31219/osf.io/qvj3b">no long-term studies</a> of the risks and only <a href="https://engineering.purdue.edu/PlumbingSafety/covid19/guidance-analysis">minimal guidance</a> to help building owners prepare their water for use again after a long shutdown. </p>
<p>As researchers involved in building water safety, we study these risks and advise building owners and public officials on actions they can take to reduce the potential for widespread waterborne disease. A <a href="https://engineering.purdue.edu/PlumbingSafety/covid19/building-water-safety-study">new paper</a> highlights these issues and our concerns that the COVID-19 stay-at-home orders may increase the chance of harmful water exposure when people return.</p>
<h2>What happens when water gets old?</h2>
<p>Just like food that sits in a refrigerator for too long, water that sits in a building’s pipes for too long can make people sick. </p>
<p><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4493479/">Harmful organisms</a>, like the bacteria that cause Legionnaire’s disease, can grow. If not maintained, devices like <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC203552/">filters</a>, <a href="https://www.cdc.gov/legionella/wmp/overview/growth-and-spread.html">water tanks</a>, <a href="https://microbiomejournal.biomedcentral.com/articles/10.1186/s40168-015-0134-1">heaters</a> and <a href="http://www.ncbi.nlm.nih.gov/pubmed/5373675">softeners</a> can become organism incubators.</p>
<p>With certain pipe materials, water can accumulate unsafe levels of <a href="https://www.sciencedirect.com/science/article/abs/pii/S0043135418303397">lead</a> and <a href="https://www.sciencedirect.com/science/article/abs/pii/S0043135416302470">copper</a>, which can cause <a href="https://www.epa.gov/ground-water-and-drinking-water/basic-information-about-lead-drinking-water">learning disabilities, cardiovascular effects</a>, <a href="https://www.nap.edu/read/9782/chapter/8#130">nausea and diarrhea</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/328913/original/file-20200419-152602-q6kn8h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/328913/original/file-20200419-152602-q6kn8h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=432&fit=crop&dpr=1 600w, https://images.theconversation.com/files/328913/original/file-20200419-152602-q6kn8h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=432&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/328913/original/file-20200419-152602-q6kn8h.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=432&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/328913/original/file-20200419-152602-q6kn8h.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=543&fit=crop&dpr=1 754w, https://images.theconversation.com/files/328913/original/file-20200419-152602-q6kn8h.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=543&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/328913/original/file-20200419-152602-q6kn8h.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=543&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Copper can leach from plumbing pipes and valves, as it did in this hotel bathtub. Ingesting water with high levels of copper can cause illnesses.</span>
<span class="attribution"><a class="source" href="https://engineering.purdue.edu/PlumbingSafety?_ga=2.123591374.457264888.1587310129-1396667686.1586369641">Andrew Whelton</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Drinking this water is a problem, but infections can also result from inhaling harmful organisms. This occurs when water splashes and becomes an aerosol, as can happen in <a href="https://www.sciencedirect.com/science/article/abs/pii/S0043135411004684?via%3Dihub">showers</a>, <a href="https://aem.asm.org/content/81/2/555">hot tubs</a> and <a href="https://www.cdc.gov/healthywater/swimming/swimmers/rwi.html">pools</a> and when <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4666014/">flushing toilets</a> or <a href="https://www.ncbi.nlm.nih.gov/pubmed/1909134">washing hands</a>. Some of these organisms can cause pneumonia-like <a href="https://www.cdc.gov/legionella/about/index.html">diseases</a>, especially in people who have weakened immune systems.</p>
<p>Water inside a building does not have an expiration date: Problems can develop within days at individual faucets, and all buildings with low water use are at risk. </p>
<h2>Keep the water flowing</h2>
<p>To avoid water issues, “fresh” water must regularly flow to a building’s faucets. Most U.S. water providers add a <a href="https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P100C8XW.txt">chemical disinfectant</a> to the water they deliver to kill organisms, but <a href="https://www.sciencedirect.com/science/article/abs/pii/S0043135419300648">this chemical disappears</a> over time.</p>
<p>Medical facilities, with their vulnerable populations, are <a href="https://www.cms.gov/Medicare/Provider-Enrollment-and-Certification/SurveyCertificationGenInfo/Downloads/QSO17-30-HospitalCAH-NH-REVISED-.pdf">required</a> to have a <a href="https://www.cdc.gov/legionella/wmp/toolkit/index.html">building water safety plan</a> to keep water fresh and prevent growth. Schools, which have long periods of low use during the summer, are <a href="https://www.epa.gov/sites/production/files/2018-09/documents/flushing_best_practices_factsheet_508.pdf">advised</a> to keep water fresh to reduce water’s lead levels.</p>
<p>Health agencies in the <a href="https://www.cdc.gov/coronavirus/2019-ncov/php/building-water-system.html">U.S.</a>, <a href="https://engineering.purdue.edu/PlumbingSafety/covid19/Canada-Guidance-Building-Water-System-Requirements-COVID-19.pdf">Canada</a>, <a href="https://engineering.purdue.edu/PlumbingSafety/covid19/Public-Health-England-Guidance-COVID-19-and-Food-Water-and-Environmental.pdf">England</a>, <a href="https://engineering.purdue.edu/PlumbingSafety/covid19/Europe-ESCMID-Guidance-COVID-Buidling-Water-System-Guidance-2020-03-27-v4-D.pdf">Europe</a> and <a href="https://www.thegardenisland.com/2020/04/18/hawaii-news/dow-flush-pipes-in-schools-hotels-weekly/">some</a> <a href="https://www.doh.wa.gov/Portals/1/Documents/1600/coronavirus/LegionellaandBuildingWaterSystemClosuresCOVID-19.pdf?_ga=2.86808280.1778946100.1585943145-1886711419.1568850380">states</a> have released recommendations in recent weeks, advising that building water be kept fresh during COVID-19 stay-at-home orders. There’s some debate over the best way to do that, but the core message is the same: <a href="https://engineering.purdue.edu/PlumbingSafety/covid19/faq-building-water-safety">Do not let water sit in buildings</a>. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/MPA926yUnWY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Flushing accomplishes several goals. Caitlin Proctor/Purdue University.</span></figcaption>
</figure>
<p>If water isn’t being used in a building, intentionally flushing the building to <a href="https://www.youtube.com/watch?v=LVwRsTnj63g&feature=y1778946100.1585943145-1886711419.1568850380">replace all the old water</a> with new water can be done <a href="https://www.nap.edu/read/25474/chapter/1">at least weekly</a>. It also helps <a href="https://www.waterrf.org/research/projects/effective-microbial-control-strategies-main-breaks-and-depressurization">remove sediments</a> that accumulate along pipe walls. </p>
<p>Faucets, water heaters and softeners, appliances such as refrigerators, toilets and other water systems, including cooling towers, all need to have water turnover. Some of these can require specialized attention. Faucet aerators should be removed because they accumulate materials and slow down the flow.</p>
<p>How long flushing takes depends on the building’s piping design, devices and the speed of water exiting the faucets. All buildings are <a href="https://youtu.be/9OHxICsaaBg">different</a>.</p>
<p>It took more than <a href="https://pubs.rsc.org/en/content/articlelanding/2016/ew/c5ew00221d#!divAbstract">80 minutes</a> of flushing to draw fresh water to the farthest faucet of one 10,000-square-foot building. In another building, it took <a href="https://engineering.purdue.edu/PlumbingSafety/resources/Example-Flush-Procedure-Actual-Office-Bldg-OnDemand-Water-Heater-2020-04-06.pdf">60 minutes</a> just to get fresh water from the water meter to the basement of a building 30 feet from the street. A single large building may take <a href="https://engineering.purdue.edu/PlumbingSafety/resources/Example-Flush-Procedure-Actual-School-2020-04-03.pdf">hours or days to clear</a>.</p>
<h2>Easier to avoid contamination than clean it up</h2>
<p>For building managers who haven’t been running the water during the pandemic, the water sitting in pipes may already have significant problems. To perform flushing, safety equipment, including <a href="https://www.osha.gov/SLTC/legionnairesdisease/control_prevention.html">masks</a>, currently in <a href="https://www.vox.com/2020/4/3/21206726/coronavirus-masks-n95-hospitals-health-care-doctors-ppe-shortage.">short supply</a>, might be needed to <a href="https://aiha-assets.sfo2.digitaloceanspaces.com/AIHA/resources/Public-Resources/RecoveringFromCOVID-19BuildingClosures_GuidanceDocument.FINAL.pdf?_ga=2.108854594.1778946100.1585943145-1886711419.1568850380">protect workers</a>. </p>
<p>A <a href="https://www.reuters.com/article/us-health-coronavirus-usa/nine-u-s-states-planning-reopening-of-economies-after-coronavirus-shutdown-idUSKCN21V185">slow “ramp-up” of the economy</a> means buildings will not reach normal water use for some time. These buildings may need flushing again and again.</p>
<p>Shock disinfection, adding a high level of disinfectant chemical to the plumbing to kill organisms living in it, may also be necessary. This is required for <a href="http://epubs.iapmo.org/2018/UPC/">new buildings</a> and is sometimes done when water in new buildings <a href="https://www.ashrae.org/technical-resources/bookstore/ansi-ashrae-standard-188-2018-legionellosis-risk-management-for-building-water-systems">sits still for too long</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/329233/original/file-20200420-152591-1uincpl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/329233/original/file-20200420-152591-1uincpl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=444&fit=crop&dpr=1 600w, https://images.theconversation.com/files/329233/original/file-20200420-152591-1uincpl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=444&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/329233/original/file-20200420-152591-1uincpl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=444&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/329233/original/file-20200420-152591-1uincpl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=557&fit=crop&dpr=1 754w, https://images.theconversation.com/files/329233/original/file-20200420-152591-1uincpl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=557&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/329233/original/file-20200420-152591-1uincpl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=557&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cut-open shower pipes reveal a biofilm with metal deposits.</span>
<span class="attribution"><a class="source" href="https://engineering.purdue.edu/PlumbingSafety?_ga=2.123591374.457264888.1587310129-1396667686.1586369641">Caitlin Proctor/Purdue University</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Inexpensive chemical disinfectant tests can help determine if the water is “fresh.” Testing for harmful organisms is recommended by <a href="https://www.doh.wa.gov/Portals/1/Documents/1600/coronavirus/LegionellaandBuildingWaterSystemClosuresCOVID-19.pdf?_ga=2.121541320.1778946100.1585943145-1886711419.1568850380">some organizations</a>. It can take several days and requires expertise to interpret results. Metals testing might be needed, too. Public health departments can provide specific recommendations for all of these actions and communication of risks.</p>
<h2>The need for standards and water safety</h2>
<p>Water left sitting in the pipes of buildings can present serious health risks. </p>
<p>Standards are lacking and very much needed for restarting plumbing and ensuring continued water safety after the pandemic passes.</p>
<p>Right now, building managers can take immediate action to prevent people from becoming sick when they return.</p>
<p>[<em>You need to understand the coronavirus pandemic, and we can help.</em> <a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=upper-coronavirus-help">Read The Conversation’s newsletter</a>.]</p><img src="https://counter.theconversation.com/content/136373/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Caitlin R. Proctor receives funding from Purdue University College of Engineering, the National Science Foundation, and Warm Springs Foundation.</span></em></p><p class="fine-print"><em><span>Andrew J. Whelton receives funding from the US National Science Foundation (CBET 2027049), US Environmental Protection Agency (R836890), Warm Springs Foundation, and Water Research Foundation.</span></em></p><p class="fine-print"><em><span>William Rhoads receives funding from the National Science Foundation (CBET 1706733). He is affiliated with the American Waterworks Association. </span></em></p>Office buildings have been left mostly empty for weeks amid the coronavirus pandemic, leaving standing water in pipes where harmful organisms can grow. What happens when those buildings reopen?Caitlin R. Proctor, Lillian Gilbreth Postdoctoral Fellow, Purdue UniversityAndrew J. Whelton, Associate Professor of Civil, Environmental & Ecological Engineering, Purdue UniversityWilliam Rhoads, Research Scientist, Virginia TechLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1218622019-08-16T12:52:36Z2019-08-16T12:52:36ZWhy are people still dying from Legionnaires’ disease?<figure><img src="https://images.theconversation.com/files/288192/original/file-20190815-136208-s9lota.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Inhaling mist contaminated with _Legionella pneumophila_ can lead to Legionnaires' disease.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/girl-shower-behind-misted-glass-takes-1227823831">Denis Klimov 3000/Shutterstock.com</a></span></figcaption></figure><p>In the nearly 50 years since epidemiologists first discovered Legionnaires’ disease, we have learned how to test for it, treat it and prevent it. So why are people still dying from it and why are more and more people becoming sick with it every single year?</p>
<p>Most recently, <a href="https://www.nytimes.com/2019/08/07/us/legionnaires-disease-atlanta-death.html">one woman died</a> and over 70 other people were infected in the largest outbreak of the disease in Georgia history after staying at the Sheraton Atlanta Hotel in mid-July. </p>
<p>From 2000 through 2017, the number of reports of Legionnaires’ disease <a href="https://www.cdc.gov/legionella/about/history.html">increased over 500% in the United States</a>. Many factors contribute to this increase: a true increase in cases, an older population at higher risk, better diagnosis, improved disease reporting and more thorough investigation of outbreaks by health departments. However, the fact remains that each year over 6,000 people are infected and over 250 people die from a disease that is <a href="http://www.cidrap.umn.edu/news-perspective/2017/06/cdc-most-healthcare-acquired-legionnaires-cases-could-be-prevented">largely preventable</a>.</p>
<p>I am an infectious disease epidemiologist at the University of Nevada, Las Vegas School of Public Health. For nearly 15 years, I investigated outbreaks of disease for the health department in Las Vegas and I dealt with Legionnaires’ disease in Las Vegas Strip hotels <a href="https://vegasinc.lasvegassun.com/business/2011/aug/23/aria-guests-sue-after-acquiring-legionnaires-disea/">on</a> <a href="https://lasvegassun.com/news/2012/jan/30/guest-who-stayed-luxor-dies-legionnaires-disease/">numerous</a> <a href="https://knpr.org/knpr/2012-02/legionnaires-strikes-again-mgm-hotels">occasions</a>, including repeatedly investigating one resort that spent <a href="https://doi.org/10.1017/S0950268811002779">eight years fighting the pathogen</a>. </p>
<h2>What is Legionnaires’ disease?</h2>
<p>Legionnaires’ disease is a respiratory disease that occurs when the bacteria <em>Legionella pneumophila</em> infect the lungs. In order to become sick, you have to inhale microscopic droplets of water that are contaminated with the bacteria. Simply drinking contaminated water is not enough to make you sick, and you cannot catch the disease from someone else who is sick. </p>
<p>It can take up to 10 days for symptoms to appear, and when they do, they initially look like a bad case of flu. The illness typically begins with a high fever, a cough, shortness of breath, muscle ache and headache. After a couple of days, these symptoms progress to pneumonia, a buildup of fluid in the lungs that makes it difficult to breathe. In <a href="https://www.cdc.gov/legionella/health-depts/surv-reporting/2014-15-surv-report-508.pdf">2014 and 2015</a>, more than 95% of people with Legionnaires’ disease wound up being hospitalized. While the disease is treatable with antibiotics, about 1 in 8 still died from their infection. </p>
<p>Although the bacteria can infect people of all ages, more than 80% of <a href="https://www.cdc.gov/legionella/health-depts/surv-reporting/2014-15-surv-report-508.pdf">reported cases</a> were 50 years old or older and about 60% were men. Smokers and people with underlying lung diseases – such as emphysema or chronic obstructive pulmonary disease – or weakened immune systems, due to medicines or health problems such as cancer or diabetes, are also at higher risk of infection.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/288195/original/file-20190815-136230-e48t2j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/288195/original/file-20190815-136230-e48t2j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/288195/original/file-20190815-136230-e48t2j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/288195/original/file-20190815-136230-e48t2j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/288195/original/file-20190815-136230-e48t2j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/288195/original/file-20190815-136230-e48t2j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/288195/original/file-20190815-136230-e48t2j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/288195/original/file-20190815-136230-e48t2j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Symptoms of Legionnaires’ disease resemble the flu.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-illustration/legionnaires-disease-legionellosis-legion-fever-signs-302169239?src=CuKPbXkOCKSoAr3Ynyy-Cw-1-5">Designua/Shutterstock.com</a></span>
</figcaption>
</figure>
<h2>How does it spread?</h2>
<p>We have learned a lot about the disease and how it spreads since it was discovered and named nearly 50 years ago. In 1976, an estimated 180 attendees of American Legion convention in Philadelphia developed a mysterious respiratory illness and <a href="https://www.cdc.gov/mmwr/preview/mmwrhtml/00045731.htm">29 died within days of the event</a>. It wasn’t until months after that outbreak that the responsible organism, <em>Legionella pneumophila</em>, <a href="https://wwwnc.cdc.gov/eid/article/23/11/ET-2311_article">was first discovered</a>. The bacteria was found growing in the hotel’s cooling tower and was spread throughout the hotel via the air conditioning system.</p>
<p>We now know that <em>Legionella pneumophila</em> can be regularly found in fresh water all over the world, which makes preventing disease a particular challenge. We also know that man-made water systems, including <a href="https://abcnews.go.com/Health/legionnaires-outbreak-traced-back-playboy-mansion/story?id=12924405">hot tubs</a>, <a href="https://dx.doi.org/10.1097%2FPHH.0000000000000558">cooling towers</a>, <a href="https://www.nytimes.com/1990/01/11/us/mist-in-grocery-s-produce-section-is-linked-to-legionnaires-disease.html">misters</a>, <a href="https://wwwnc.cdc.gov/eid/article/8/1/01-0176_article">fountains</a>, hot water tanks, and even the complex plumbing systems in big buildings can grow and spread <em>Legionella</em>. </p>
<p>Two things have to happen for a person to develop Legionnaires’ disease. First, a person has to be exposed to the bacteria through inhaling small droplets of water. Then the bacteria has to multiply until there are enough of them to cause disease. The first factor is impossible to control, as exposure occurs through breathing contaminated water. For example, if you take a shower, there is no way to prevent breathing in the fine mist created by the shower head. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/288197/original/file-20190815-136203-1gcvhbz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/288197/original/file-20190815-136203-1gcvhbz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/288197/original/file-20190815-136203-1gcvhbz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/288197/original/file-20190815-136203-1gcvhbz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/288197/original/file-20190815-136203-1gcvhbz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/288197/original/file-20190815-136203-1gcvhbz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/288197/original/file-20190815-136203-1gcvhbz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/288197/original/file-20190815-136203-1gcvhbz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Legionnaires’ disease was named for an outbreak at a conference of the American Legion.</span>
<span class="attribution"><span class="source">Glynnis Jones/Shutterstock.com</span></span>
</figcaption>
</figure>
<h2>High risk times for <em>Legionella</em></h2>
<p>Because these bacteria are found everywhere in fresh water, it is impossible to keep them from being introduced into a water system. That leaves society with the challenge of controlling the number of bacteria. The bacteria can live a long time in the pipes that are part of a larger water system, such as those that are in hotels and nursing homes, and when a person turns on the shower in a hotel, <em>Legionella</em> comes tumbling out, too.</p>
<p>The most important factor in preventing <em>Legionella</em> growth in pipes and the water system is to control the temperature of the water. These bacteria grows best at temperatures between <a href="https://www.who.int/water_sanitation_health/emerging/legionella.pdf">77 and 108 degrees Fahrenheit</a>. The longer water sits in pipes, such as those in a hotel room that is unoccupied for several days, the more likely it is that it will be in that temperature danger zone and the bacteria will flourish. This is why Legionnaires’ disease cases spike in the <a href="https://www.cdc.gov/legionella/health-depts/surv-reporting/2014-15-surv-report-508.pdf">summer and early fall</a> when it is harder to keep the water out of that temperature danger zone. </p>
<p>Ultimately, the responsibility for preventing Legionnaires’ disease falls on the shoulders of the building owners and managers to implement a comprehensive <a href="https://www.cdc.gov/legionella/wmp/index.html">water management program</a> of the complex water systems in their facility. Unlike private homes, commercial buildings have miles of pipe where water may sit for long periods of time, water-based cooling systems, large spas and decorative fountains – and these all have to be properly maintained to prevent <em>Legionella</em> growth. This is particularly important for hospitals and nursing homes, as 20% of Legionnaires’ cases are acquired in health care settings by people who are at high risk for infection. However, as we have seen in the outbreak in Atlanta, and in hundreds of other outbreaks over the years, Legionnaires’ disease can affect anyone at any time. </p>
<p>As we start to understand <a href="https://www.ajc.com/news/officials-confirm-first-legionnaires-death-linked-atlanta-outbreak/qlcU6tCtW4hA3LRQThlfiK/">what went wrong in Atlanta</a>, public health experts might learn more about how to prevent Legionnaires’ disease. It’s then up to building owners and operators to put the necessary protections in place throughout the country. Unfortunately the public can’t do much more than hold their breath. </p>
<p>[ <em><a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=signupinsight">Sign up for The Conversation’s newsletter to get insight each day</a></em> ]</p><img src="https://counter.theconversation.com/content/121862/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Brian Labus was previously funded by grants from the Centers for Disease Control and Prevention for disease surveillance and outbreak investigation activities, including Legionnaires' disease.</span></em></p>A woman recently died from Legionnaires’ disease at an Atlanta hotel. Why? The cause is known and the disease is largely preventable. Yet the number of cases in the US continue to rise.Brian Labus, Assistant Professor of Epidemiology and Biostatistics, University of Nevada, Las VegasLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/885692018-01-24T19:17:01Z2018-01-24T19:17:01ZDon’t worry, the chance of dying from potting mix is very slim<figure><img src="https://images.theconversation.com/files/202982/original/file-20180123-182951-17fu2wn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Potting mix is known to carry harmful bacteria and fungi.</span> <span class="attribution"><a class="source" href="https://unsplash.com/photos/7LsyosoO0GQ">Photo by Markus Spiske on Unsplash</a></span></figcaption></figure><p>Gardening is generally a healthy and pleasurable hobby or occupation. However, any activity carries some risk – and gardening is no exception. </p>
<p>Potting mix is known to carry harmful bacteria and fungi. And there have been <a href="http://www.dailymail.co.uk/news/article-2762227/Family-mourns-mother-two-killed-bacteria-potting-mix.html">reports of deaths</a> from diseases, such as the <a href="http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=11144971">Legionnaires’ disease</a> (a lung infection), that have been attributed to bacteria in potting mix.</p>
<p>Many bacteria and fungi that can cause infections in people live in soil and water. So it’s not surprising that potting mix can also have in it bacteria and fungi that may on occasion cause harm to people, and in rare cases even kill them. But it’s important to note that, overall, the risk is very low. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-science-is-in-gardening-is-good-for-you-65251">The science is in: gardening is good for you</a>
</strong>
</em>
</p>
<hr>
<h2>Fertilising more than plants</h2>
<p>Potting mix is usually a mixture of inorganic and organic material. It’s also often at a higher temperature compared to soil because of where and how it’s stored, so it retains heat for longer. Bacteria and fungi generally grow better and reach higher numbers when they are in moist and warm environments.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/202994/original/file-20180123-182973-3e1b6d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/202994/original/file-20180123-182973-3e1b6d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/202994/original/file-20180123-182973-3e1b6d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=467&fit=crop&dpr=1 600w, https://images.theconversation.com/files/202994/original/file-20180123-182973-3e1b6d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=467&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/202994/original/file-20180123-182973-3e1b6d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=467&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/202994/original/file-20180123-182973-3e1b6d.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=587&fit=crop&dpr=1 754w, https://images.theconversation.com/files/202994/original/file-20180123-182973-3e1b6d.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=587&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/202994/original/file-20180123-182973-3e1b6d.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=587&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Potting mix is usually warmer than soil, which makes it a better environment for bacteria and fungi to grow.</span>
<span class="attribution"><span class="source">from shutterstock.com</span></span>
</figcaption>
</figure>
<p>If bacteria or fungi are already present in low numbers, they can quickly grow to very high numbers in optimal conditions. This includes many bacteria in soil that can cause problems in people – such as strains of <em>nocardia</em> (causes nocardiosis, an infection of the lungs or whole body), <em>legionella</em> (causes Legionnaires’ disease), and <em>clostridium</em> (causes tetanus).</p>
<p>Numerous fungi can also be present in soil and potting mix. In certain areas of the world, soil contains fungi that can invade if inhaled and cause disease. These include the <a href="https://www.cdc.gov/fungal/diseases/histoplasmosis/index.html">lung infection histoplasmosis</a>, which is caused by a fungus that lives mainly in parts of the United States, but also in some parts of Central and South America, Africa, Asia, and Australia.</p>
<h2>Protecting ourselves</h2>
<p>The risk to most people of becoming infected with any of these bacterial or fungal diseases is very low. Disease is more likely to be a risk when the micro-organisms are present in very high numbers.</p>
<p>Bacteria or fungi also need to be introduced into our bodies to cause disease. This usually happens through inhalation, where the organisms go into the lungs. It can also occur through the skin, such as with the chronic fungal infection <em>sporotrichosis</em>, also known as “rose gardener’s disease”. If, for any reason, micro-organisms are present in high numbers, then the exposure and risk will be higher. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/203130/original/file-20180124-33538-1a0l3x6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/203130/original/file-20180124-33538-1a0l3x6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/203130/original/file-20180124-33538-1a0l3x6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/203130/original/file-20180124-33538-1a0l3x6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/203130/original/file-20180124-33538-1a0l3x6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/203130/original/file-20180124-33538-1a0l3x6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/203130/original/file-20180124-33538-1a0l3x6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/203130/original/file-20180124-33538-1a0l3x6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=504&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A fungal infection known as rose gardener’s disease can happen with the organism entering the skin directly through an injury.</span>
<span class="attribution"><span class="source">from shutterstock.com</span></span>
</figcaption>
</figure>
<p>There are many things we can do to protect ourselves from introducing bacteria or fungi into our bodies. The most essential is basic hygiene.</p>
<p>If people smoke, eat or drink without first washing their hands, they are at an <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2870547/">increased risk of legionella infection</a> from potting mix. This implies direct inhalation isn’t the only way for the bacteria to enter the body, but that oral intake of micro-organisms via contaminated hands is also a risk.</p>
<p>Another added <a href="https://assist.asta.edu.au/sites/assist.asta.edu.au/files/AIS%20Safe%20handling%20and%20use%20of%20potting%20mix_2.pdf">protection measure</a> is wearing gloves. This doesn’t mean you should then not wash your hands before eating. A physical barrier in addition to washing hands obviously provides better protection.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/at-least-five-reasons-you-should-wear-gardening-gloves-89451">(At least) five reasons you should wear gardening gloves</a>
</strong>
</em>
</p>
<hr>
<p>Masks can be worn in high-risk situations, such as when opening a bag of potting mix. Directing the bag away from the gardener when opened, and being in a well-ventilated area, will decrease any inhalation risk. </p>
<h2>Signs of infection</h2>
<p>People who have a lower immunity, such as those with diseases such as HIV or lymphoma, are more at risk of catching something from potting mix. So it’s even more important they use extra appropriate precautions, including wearing masks when in higher-risk situations. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/199830/original/file-20171219-27568-1inhzrd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/199830/original/file-20171219-27568-1inhzrd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/199830/original/file-20171219-27568-1inhzrd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/199830/original/file-20171219-27568-1inhzrd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/199830/original/file-20171219-27568-1inhzrd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/199830/original/file-20171219-27568-1inhzrd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/199830/original/file-20171219-27568-1inhzrd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Simple safety provisions can protect us from harmful bacteria and fungi.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>The symptoms or signs of infection acquired from soil or potting mix depend on where the infection is and what micro-organism is causing it. With potting mix, the main worry is <em>legionella longbeachae</em>. This generally causes a lung infection such as pneumonia. </p>
<p>Symptoms can initially be fever, aches and pains, which are fairly general of illness. But as the infection involves more of the respiratory tract, cough, shortness of breath and/or pain on breathing may develop.</p>
<h2>Treatment</h2>
<p>While <a href="https://www.cdc.gov/mmwr/preview/mmwrhtml/mm4934a1.htm">potting-mix-linked legionella infections</a> are uncommon, cases have occurred in countries including Australia, Japan and the US. </p>
<p>So, if people develop symptoms that are ongoing and have had recent exposure to potting mix within the incubation period (two to ten days after exposure), they need to <a href="http://www.masulacompliance.com.au/news/what-you-should-know-if-you-work-with-soils-compost-and-potting-mix">seek medical help</a> and make it clear to that person that they were worried about potting mix being involved. </p>
<p>It’s important to note the potting mix connection because antibiotics needed to kill <em>legionella</em> are different to standard penicillin-like antibiotics often used to treat pneumonia acquired in the community.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/are-common-garden-chemicals-a-health-risk-65643">Are common garden chemicals a health risk?</a>
</strong>
</em>
</p>
<hr>
<p>Overall, though, we need to keep these risks in perspective. Millions of people garden and all will be exposed to soil and/or potting mix. Very few of these infections occur in Australia and elsewhere. Fairly simple provisions such as washing hands, wearing gloves and – where necessary – wearing a mask will ensure rates of infection remain low.</p><img src="https://counter.theconversation.com/content/88569/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Peter Collignon does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The risk of bacterial or fungal infection from potting mix is very low. Wearing gloves and washing your hands will keep it even lower.Peter Collignon, Professor, infectious diseases and microbiology, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/762122017-04-13T03:15:02Z2017-04-13T03:15:02ZDon’t worry, the odds of catching legionnaires’ disease in Melbourne are pretty slim<figure><img src="https://images.theconversation.com/files/165173/original/image-20170413-25859-6bbfog.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Melbourne city-goers shouldn't be concerned, unless they're in a group vulnerable to contracting legionnaires'.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/bonitoclub/6797911793/in/photolist-bmH5kK-dEx4Zv-ef5c42-aBzigo-ehfXnV-aBwFKr-fdbp3S-at6Um5-aT7MYx-nDbkgn-ehMMvJ-93XoDb-8Xn8HU-9cW7LA-7iSkLY-a8mCfy-9bDwaq-95Ss3V-7DoQmY-dDvn6d-fcW4Uv-ejEGLS-aQMLVc-b3qVN4-aBzgGf-aEjbye-awoZfM-9onNKk-96AfLw-i1UmdG-awp9uK-8nHvhE-fcW4ax-7TZFrg-kTAA8h-oBJagL-eg5Pkp-SoquJr-HjPk3-9qunTZ-9ngjHq-jDTQm7-91BmrC-einUPB-6RcXik-9iDWQY-a6hDRw-9hkVfa-bpdiFC-eSu1ba">Tony & Wayne/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>The current suspected <a href="http://www.abc.net.au/news/2017-04-12/five-cases-of-legionnaires-disease-in-melbournes-cbd-investigate/8439660">outbreak of legionnaires’ disease</a> in Melbourne is a serious public health concern. Victorian health authorities say the circulation of the disease may be linked to cooling towers in Melbourne’s CBD. </p>
<p>So how does this happen? And with five people recovering in hospital, should the public be worried?</p>
<h2>Cooling towers</h2>
<p>Cooling towers recirculate water against a flow of air. This cools down the water that is then used in air conditioning and other appliances. As it goes through the appliances, the water warms up, and warm wet air is then expelled into the environment.</p>
<p>To maximise the cooling effect, such towers are designed to have a large surface area for heat transfer. </p>
<p>Legionella bacteria are relatively common in a water environment. However, they are not abundant, which means they rarely reach large numbers. But once they enter a cooling tower things change. </p>
<p>The combination of recirculating warm water (27 to 35°C), large surface areas for heat exchange and a continuous flow of nutrients from the cooling (and warming) process, creates perfect conditions for the bacteria to grow in slimes called biofilms. </p>
<p>Add the constant release of warm wet air containing the bacteria and it is obvious why they can be a problem.</p>
<p>Cooling towers that are well designed, maintained and disinfected rarely cause a problem. Almost all documented outbreaks are <a href="http://www.who.int/water_sanitation_health/emerging/legionella.pdf">associated with problems</a> with design, maintenance or disinfection – often all three.</p>
<h2>When does it happen?</h2>
<p>Although outbreaks of disease from cooling towers can happen at any time, they <a href="https://www.ncbi.nlm.nih.gov/pubmed/8405155">tend to occur in Autumn</a>. This is due to a combination of factors. </p>
<p>At the end of summer, a cooling tower has had plenty of time to incubate legionella if they are allowed. The bacteria inhabit slimes that can coat the large surface area within the system fed by the nutrients from the incoming air supply. </p>
<p>In autumn, as the weather cools down, towers are used less frequently. In Australia long weekends, such as ANZAC weekend and Easter, mean cooling towers are switched off for a few days. The temperatures drop and nutrient supply ceases in the system. This causes the legionella-rich slimes to detach from the surfaces. </p>
<p>When the tower is turned back on, following the long weekend, the immediate effect is to dislodge the slimes and then release them into the environment around the cooling tower. </p>
<p>Autumn assists the travel of the contaminated air as it is cooler, more humid and there are lower UV indexes. This means the fine water particles, called aerosol, can travel for long distances some several kilometres from the source.</p>
<p>Historically in Australia a <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1753-6405.1994.tb00214.x/full">number of outbreaks</a> of legionnaire’s disease have <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1753-6405.1994.tb00214.x/full">occurred around Autumn</a> long weekends.</p>
<h2>Who is at risk?</h2>
<p>In Australia we average just more than <a href="http://www.health.gov.au/cdnareport">300 cases of this disease</a> per year. Around half of these come from water systems. So the chances of becoming infected are roughly one in 100,000. Cooling towers are identified sources of less than half of these infections, so less than one in 200,000.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/165175/original/image-20170413-25886-1nu76y9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/165175/original/image-20170413-25886-1nu76y9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/165175/original/image-20170413-25886-1nu76y9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/165175/original/image-20170413-25886-1nu76y9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/165175/original/image-20170413-25886-1nu76y9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/165175/original/image-20170413-25886-1nu76y9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/165175/original/image-20170413-25886-1nu76y9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/165175/original/image-20170413-25886-1nu76y9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Symptoms of the disease vary from a cold or flu-like illness to serious pneumonia.</span>
<span class="attribution"><span class="source">from shutterstock.com</span></span>
</figcaption>
</figure>
<p>Only 5% of people who are exposed to contaminated water <a href="http://www.who.int/water_sanitation_health/emerging/legionella.pdf">will show any signs</a> of disease. Those who do show signs may have anything from a cold or flu-like illness through to very serious and life threatening pneumonia. </p>
<p>The 5% of infected people <a href="http://www.who.int/water_sanitation_health/emerging/legionella.pdf">have common traits</a>. Around two-thirds are males. Heavy smoking and high alcohol consumption are probably the highest risk factor. Being over 50 is another, as our immune systems start going downhill from our thirties onwards. </p>
<p>Another important factor is people with depressed immune systems. This includes transplant recipients and cancer patients who have artificially low immunity. It also includes those with existing lung conditions or other chronic disabilities such as diabetes and kidney problems.</p>
<p>To be infected from a cooling tower the susceptible person must inhale the contaminated aerosol. This means they must be within the vicinity of the source. The disease <a href="http://www.who.int/water_sanitation_health/emerging/legionella.pdf">will show itself</a> within two to 21 days after exposure - most often around five to six days afterwards. </p>
<h2>What now?</h2>
<p>At this stage in Melbourne there are undoubtedly a lot of concerned cooling tower operators making sure they are not to blame. They will be being assisted by the health department. The problem will most likely be over within 30 days. </p>
<p>The number of new cases, if they are going to increase, will most likely do so in the next five to seven days – a single period of incubation – and then subside. </p>
<p>If you have been in the Melbourne CBD in the last two weeks, it is unlikely you have been exposed and need to worry. If you are one of the high-risk individuals stay calm, but if symptoms of cold or flu appear suddenly with a dry cough and fever over the next couple of weeks seek medical advice immediately. </p>
<p>Your GP should already be on alert for signs of legionnaire’s disease and can probably give you the all clear within an hour.</p>
<p>It is unlikely that you are at any increased risk of catching the disease by going to the CBD now that the cases have been identified and action is being taken. And given the odds quoted above you might have a better chance of winning the lottery.</p><img src="https://counter.theconversation.com/content/76212/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Richard Bentham has received funding from Australian Research Council, Victorian Health Department, Flinders University Internal Grants schemes. He is a Fellow of the Royal Society for Public Health.</span></em></p>Should the public be worried about the recent outbreak of legionnaires’ disease in Melbourne’s CBD?Richard Bentham, Associate Professor of Public Health Microbiology, Flinders UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/287532014-07-04T04:57:09Z2014-07-04T04:57:09ZBirthing pools recalled after case of Legionnaires – so, should you be worried?<figure><img src="https://images.theconversation.com/files/52956/original/tzbsx2b7-1404385938.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Home or away?</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/eyeliam/7167903447/sizes/l">Jason Lander</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>The <a href="http://www.theguardian.com/society/2014/jul/01/home-birthing-pools-recalled-nhs-public-health-england-after-baby-falls-ill-legionnaires-disease">recall of hired home-birthing pools</a> after a baby contracted Legionnaires’ disease will inevitably lead some women to worry about having a water birth at home. While the incidence is rare, it is worth keeping in mind some clear guidelines about how to best use a water pool.</p>
<p>Home birth is an option for women who are at low risk of complications, but it is certainly not widespread. In the UK, the percentage of women who have their baby at home is very low – only <a href="http://www.ons.gov.uk/ons/datasets-and-tables/index.html">2.3% in 2012</a> (included in this figure are many home births that are unplanned). Others who plan home births initially labour at home using water, but <a href="https://www.npeu.ox.ac.uk/birthplace/publications">then transfer to hospital</a> for additional pain relief.</p>
<p>But about <a href="http://www.biomedcentral.com/1471-2393/14/60">half of women who planned home births</a> use water birth pools, as immersion in water <a href="http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD000111.pub3/abstract">helps relieve pain</a>. </p>
<p>In the case of the baby with Legionnaires’, it was born in a pool that was pre-filled and kept heated for several days before. The recommended water temperature for water birth pools is 36-37°C so that during labour the baby is not overheated or shocked by cold water. But this is also an ideal temperature for many bacteria to flourish in, including the Legionnelle bacteria, which <a href="http://www.nhs.uk/conditions/Legionnaires-disease/Pages/Introduction.aspx">cause a severe lung infection</a>. So the recommendation is that home birth pools should never be pre-filled and kept warm. This is the reason that hot tubs that aren’t cleaned and looked after <a href="http://www.bbc.co.uk/news/health-19097187">have also been implicated</a> in cases of Legionnaires’ disease.</p>
<p>Some women may be tempted to pre-fill the pool when they know they could go into labour so that they don’t have to wait while it fills up when labour starts, or to try it out beforehand. But a good idea is to fill it with cold water to see how long it takes to fill – most only take 10-20 minutes – before emptying, cleaning and drying the pool until it’s actually needed, which will also give you an idea of when to start the process. This would prevent the unusual Legionnaire bacteria but also more common bacteria.</p>
<h2>Hiring a pool</h2>
<p>Not all women buy pools because they are for a one-off use or because buying one may be too expensive. Some NHS Trusts provide a rigid shell and women can then purchase a disposable liner, although many are hired privately. These hired pools come in a variety of types, usually free standing, and can have inflatable or rigid frames with disposable liners. Most come with pumps and pipes to aid filling and draining and most companies provide advice about safety and hygiene which should be read and adhered to. Even so, it’s ideal to discuss the pool, how and when to fill it and ensure it’s clean and safe with a midwife. </p>
<p>While an investigation into how the baby contracted Legionnaires’ is carried out, certain types of birthing pool have been banned by the NHS and Public Health England (PHE) until further notice. Heated pools from the particular supplier in this case have been recalled and a further six companies that hire out pools are being questioned over whether they carry out the right risk assessments. </p>
<p>Concerns about infection are not new. But a Cochrane review I lead that looked at the evidence to date <a href="http://www.ncbi.nlm.nih.gov/pubmed/19370552">showed no difference</a> in the incidence of infection in mothers or babies using a variety of pools, both plumbed in and free-standing. Importantly, however, all were filled at the time of use, were carefully maintained, with strict cleaning regimes, or with one time use only liners. </p>
<p>The concept of a pool that is pre-filled and kept warm is a new phenomenon but not one that is recommended in any NHS facility. The risk of infection is well recognised and all NHS facilities have policies and processes that include birth pools being filled at the time they are needed, are thoroughly cleaned and dried after every use and monitored for potential infections. Most good companies would recommend similar precautions. </p>
<p>All midwives are also very aware of the risk of infection and any woman considering birth at home or using water during birth should speak to her midwife about her plans. Advice in local waterbirth workshops for expectant parents also now explicitly includes not using pre-filled/heated pools because of the rare but possible infection risk.</p>
<p>There are important advantages for women giving birth at home, such as a sense of well-being from being in their own environment. The use of water during labour and birth is likely to be a contributing factor to this, so it is vital that women have all the information they need to safely birth at home and use water immersion during labour if they wish. </p>
<p>So the key message must be that any infection is unusual – and legionnaires extremely rare – but good practice when it comes to birthing pools, and under the guidance of a midwife, will contribute to a positive birth experience for all. </p><img src="https://counter.theconversation.com/content/28753/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Elizabeth Cluett was lead reviewer on the Cochrane review into outcomes from immersion in water during labour and birth</span></em></p>The recall of hired home-birthing pools after a baby contracted Legionnaires’ disease will inevitably lead some women to worry about having a water birth at home. While the incidence is rare, it is worth…Elizabeth Cluett, Director of Programs for Family, Child and Psychosocial Health. Lead Midwife for Education., University of SouthamptonLicensed as Creative Commons – attribution, no derivatives.