tag:theconversation.com,2011:/es/topics/lice-40447/articleslice – The Conversation2021-04-23T01:44:23Ztag:theconversation.com,2011:article/1551402021-04-23T01:44:23Z2021-04-23T01:44:23ZEndless itching: how Anzacs treated lice in the trenches with poetry and their own brand of medicine<figure><img src="https://images.theconversation.com/files/396455/original/file-20210422-13-ndzwj8.jpg?ixlib=rb-1.1.0&rect=2%2C4%2C990%2C740&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://tiaki.natlib.govt.nz/#details=ecatalogue.135565">Royal New Zealand Returned and Services' Association Collection, Alexander Turnbull Library, Wellington, NZ (Tiaki reference number 1/4-009458-G)</a></span></figcaption></figure><p>We think we know a lot about Australian and New Zealand soldiers’ health in the first world war. Many books, novels and television programs speak of wounds and war doctors, documenting the work of both Anzac nations’ medical corps. </p>
<p>Often these histories begin with front-line doctors — known as <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5229383/">regimental medical officers</a> — who first reached wounded men in the field. The same histories often end in the hospital or at home.</p>
<p>Yet, much of first world war medicine began and ended with the soldiers themselves. Australian and New Zealand soldiers (alongside their British and Canadian counterparts) cared for their own health in the trenches of the <a href="http://anzaccentenary.vic.gov.au/westernfront/history/index.html">Western Front</a> and along the cliffs of <a href="https://www.awm.gov.au/articles/encyclopedia/gallipoli">Gallipoli</a>. </p>
<p>This “vernacular” medicine spread from solider to soldier by word of mouth, which they then recorded in diaries and letters home. It spread through written texts, such as <a href="https://theconversation.com/the-comfort-of-reading-in-wwi-the-bibliotherapy-of-trench-and-hospital-magazines-158880">trench newspapers and magazines</a>, and through constant experimentation. </p>
<p>Soldiers presented a unique understanding of their experiences of illness, developed their own health practices, and formed their own medical networks. This formed a unique type of medical system.</p>
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Read more:
<a href="https://theconversation.com/flies-filth-and-bully-beef-life-at-gallipoli-in-1915-39321">Flies, filth and bully beef: life at Gallipoli in 1915</a>
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<h2>What was this type of medicine like?</h2>
<p>Soldiers’ vernacular medicine becomes clear when looking at one significant example of war diseases — infestation with body lice — which caused <a href="https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(16)30003-2/fulltext">trench fever</a> and <a href="https://www.who.int/ith/diseases/typhusfever/en/">typhus</a>. </p>
<p>The men’s understandings of the effect of lice on the body often contrasted to that of medical professionals. </p>
<p>Soldiers described lice as a daily nuisance rather than vectors of disease. The men sitting in the trenches were preoccupied with addressing the immediate and constant discomfort caused by lice, whereas medical researchers and doctors were more concerned with losing manpower from lice-borne disease.</p>
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Read more:
<a href="https://theconversation.com/life-on-us-a-close-up-look-at-the-bugs-that-call-us-home-25754">Life on Us: a close-up look at the bugs that call us home</a>
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<p>Many men focused on the endless itching, which some said drove them almost mad. </p>
<p>Corporal George Bollinger, a New Zealand bank clerk from Hastings, <a href="https://ndhadeliver.natlib.govt.nz/delivery/DeliveryManagerServlet?dps_pid=IE16663681&dps_custom_att_1=emu">said</a>: “the frightful pest ‘lice’ is our chief worry now”.</p>
<p>Australian Private Arthur Giles shuddered when he wrote home about the lice, <a href="https://transcripts.sl.nsw.gov.au/page/giles-papers-9-may-1914-13-may-1919-arthur-clyde-giles-page-84">noting it</a>: “makes me scratch to think of them”.</p>
<h2>Soldiers experimented</h2>
<p>Soldiers’ reactions to lice, as a shared community, inspired them to experiment and share practical ideas of how to manage their itchy burdens. This included developing their own method of bathing.</p>
<p>When New Zealand Corporal Charles Saunders descended the cliffs to the beaches around Anzac Cove, <a href="https://www.iwm.org.uk/collections/item/object/1030011851">he would</a> “dive down and nudge a handful of sand from the bottom and rub it over [his] skin”, letting “the saltwater dry on one in the sun”. He also rubbed the sand across his uniform hoping to kill some of the lice eggs in the seams of his shirt and pants. </p>
<p>In some locations, fresh water was scarce and reserved for drinking. Without access to water, soldiers’ extermination methods became more offbeat, creative and original. </p>
<p>Men sourced <a href="https://www.aucklandartgallery.com/explore-art-and-ideas/artwork/4522/keatings-powder-poster">lice-exterminating powders</a>, such as Keating’s and Harrison’s, from patent providers — retail pharmaceutical sellers in the UK or back home in Australia and New Zealand — and rubbed various oils over their bodies. </p>
<p>Yet, one of the most popular extermination methods was “chatting” — popping the louse between the thumbnails.</p>
<figure class="align-center ">
<img alt="Soldiers delousing clothing outside tents" src="https://images.theconversation.com/files/396453/original/file-20210422-17-l1c12p.JPG?ixlib=rb-1.1.0&rect=3%2C0%2C1097%2C659&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/396453/original/file-20210422-17-l1c12p.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=360&fit=crop&dpr=1 600w, https://images.theconversation.com/files/396453/original/file-20210422-17-l1c12p.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=360&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/396453/original/file-20210422-17-l1c12p.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=360&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/396453/original/file-20210422-17-l1c12p.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=452&fit=crop&dpr=1 754w, https://images.theconversation.com/files/396453/original/file-20210422-17-l1c12p.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=452&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/396453/original/file-20210422-17-l1c12p.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=452&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="caption">Five soldiers delousing (‘chatting’) their infested clothing outside their tents.</span>
<span class="attribution"><a class="source" href="https://www.awm.gov.au/collection/C1000712">Australian War Memorial (photograph C00748)</a></span>
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<p>An Australian bootmaker, Lieutenant Allan McMaster, <a href="https://www.awm.gov.au/collection/C92857">told his family</a> in Newcastle it was “amusing indeed to see all the boys at the first minute they have to spare, to strip off altogether and have what we call a chating [sic] parade”. </p>
<p>Corporal Bert Jackson, an orchardist from Upper Hawthorn in Melbourne, <a href="https://www.awm.gov.au/collection/C92683">took his</a> “shirt off and had a hunt, and then put it on inside out”. He said that if he “missed any, the beggars will have a job to get to the skin again”. </p>
<h2>Soldiers shared their knowledge</h2>
<p>These soldiers shared their practices via their own medical networks, such as trench newspapers.</p>
<p>For instance, soldiers wrote humorous poems that also educated their fellow men. Australian Lance Corporal TA Saxon <a href="http://digital.sl.nsw.gov.au/delivery/DeliveryManagerServlet?embedded=true&toolbar=false&dps_pid=IE3673775">joked about</a> lice-exterminating powders in his poem A Dug-Out Lament:</p>
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<p>[…] They’re in our tunics, and in our shirts,</p>
<p>They take a power of beating,</p>
<p>So for goodness sake, if you’re sending us cake, Send also a tin of Keating. </p>
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<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/396451/original/file-20210422-23-j8lt9m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Chatting by the Wayside" src="https://images.theconversation.com/files/396451/original/file-20210422-23-j8lt9m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/396451/original/file-20210422-23-j8lt9m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=868&fit=crop&dpr=1 600w, https://images.theconversation.com/files/396451/original/file-20210422-23-j8lt9m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=868&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/396451/original/file-20210422-23-j8lt9m.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=868&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/396451/original/file-20210422-23-j8lt9m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1090&fit=crop&dpr=1 754w, https://images.theconversation.com/files/396451/original/file-20210422-23-j8lt9m.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1090&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/396451/original/file-20210422-23-j8lt9m.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1090&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">Soldiers shared cartoons and jokes about delousing via magazines and newspapers, such as this one in March 1918.</span>
<span class="attribution"><span class="source">Mitchell Library, State Library of NSW (Q91/244, FL3509202)</span></span>
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<p>One image from the trench newspaper “Aussie: the Australian soldiers’ magazine” came with <a href="http://digital.sl.nsw.gov.au/delivery/DeliveryManagerServlet?embedded=true&toolbar=false&dps_pid=IE3508591">the caption</a> “Chatting by the Wayside” that drew on the well-trod joke about the double meaning of the word chatting.</p>
<h2>What can we learn?</h2>
<p>Reflecting on these often-overlooked aspects of the past helps us rethink medicine today.</p>
<p>For marginal groups in particular, access to professional health care can, and has often been, an expensive, alienating, or culturally foreign and abrasive task. So even in today’s globalised world, networks of non-professional medicine are as active as ever.</p>
<p>With many people isolated and at the mercy of much conflicting information, informal medical networks (often found on social media) present an opportunity to allay fears and swap information in a similar manner to how Anzac soldiers communicated via trench newspapers. </p>
<p>Perhaps some forms of vernacular medicine are occurring right under our noses.</p>
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Read more:
<a href="https://theconversation.com/the-comfort-of-reading-in-wwi-the-bibliotherapy-of-trench-and-hospital-magazines-158880">The comfort of reading in WWI: the bibliotherapy of trench and hospital magazines</a>
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<img src="https://counter.theconversation.com/content/155140/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Georgia McWhinney received funding from the Federal Government of Australia. </span></em></p>Anzac soldiers wrote poetry about body lice, shared treatment tips and experimented with new ways of bathing.Georgia McWhinney, Honorary Postdoctoral Associate, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1171832019-08-15T02:13:07Z2019-08-15T02:13:07ZHow ancient seafarers and their dogs helped a humble louse conquer the world<figure><img src="https://images.theconversation.com/files/287955/original/file-20190814-136176-dom5tp.jpg?ixlib=rb-1.1.0&rect=0%2C2%2C995%2C606&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Male (left) and female Heterodoxus spiniger from Borneo.</span> <span class="attribution"><span class="source">Natural History Museum, London</span>, <span class="license">Author provided</span></span></figcaption></figure><p>This is the story of how a parasitic, skin-chewing insect came to conquer the world. </p>
<p>For more than a century, scientists have been puzzled as to how an obscure louse native to Australia came to be found on dogs across the world. <em>Heterodoxus spiniger</em> evolved to live in the fur of the agile wallaby. </p>
<p>Despite little evidence to back the idea, many researchers believed it was linked to <a href="https://www.tandfonline.com/doi/abs/10.2752/175303709X434149">people from Asia bringing the dingo to Australia</a> in ancient times. Perhaps people later took dingoes infested with this parasite back home, where it spread to local dogs, and onwards from there. </p>
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Read more:
<a href="https://theconversation.com/dingoes-do-bark-why-most-dingo-facts-you-think-you-know-are-wrong-68816">Dingoes do bark: why most dingo facts you think you know are wrong</a>
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<p>But when we approached the question again using the most up-to-date information, my colleague Peter Contos and I came up with a completely different explanation – one that better fits what we know of ancient migration and trade in the Asia-Pacific region.</p>
<p>As we report in the journal <a href="https://www.tandfonline.com/doi/full/10.1080/14614103.2019.1653619">Environmental Archaeology</a>, this louse probably originated not in Australia but in New Guinea, an island with a long history of intimate connection with seafaring Asian cultures.</p>
<h2>Louse on the loose</h2>
<p><em>H. spiniger</em> is a tiny louse that lives on mammals around the world, mostly dogs. Using its clawed legs to hang on, it bites and chews at the skin and hair of its hosts to draw the blood on which it feeds.</p>
<p>As all its closest relatives are <a href="https://www.sciencedirect.com/science/article/abs/pii/0020751994901953">specialised parasites of marsupials</a>, mostly other wallabies, logic suggested that <em>H. spiniger</em> must have evolved within Australia. It also seemed logical it would have spread first to the dingo, Australia’s native dog.</p>
<p>Our first task was to figure out just how far away from Australia it had spread; this would inform the likely pathways by which it could have travelled to the wider world. </p>
<p>We looked at museum collections, entomological surveys, and veterinary research reports to generate a map of its worldwide distribution.</p>
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<a href="https://images.theconversation.com/files/287951/original/file-20190814-136186-1ddmp4k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/287951/original/file-20190814-136186-1ddmp4k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/287951/original/file-20190814-136186-1ddmp4k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=268&fit=crop&dpr=1 600w, https://images.theconversation.com/files/287951/original/file-20190814-136186-1ddmp4k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=268&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/287951/original/file-20190814-136186-1ddmp4k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=268&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/287951/original/file-20190814-136186-1ddmp4k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=337&fit=crop&dpr=1 754w, https://images.theconversation.com/files/287951/original/file-20190814-136186-1ddmp4k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=337&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/287951/original/file-20190814-136186-1ddmp4k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=337&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">Global distribution of <em>H. spiniger</em>.</span>
<span class="attribution"><span class="source">Lougoulos and Contos</span>, <span class="license">Author provided</span></span>
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<p>The specimens we found, collected from the late 19th century to the present day, showed that this species is found on every continent except Europe and Antarctica.</p>
<p>But in Australia, we couldn’t find a single verifiable instance of the parasite living on dingoes. The only cases were from agile wallabies and domestic dogs.</p>
<p>That meant the prevailing wisdom had been wrong, and we had to look elsewhere for the origins of <em>H. spiniger</em>.</p>
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<img alt="" src="https://images.theconversation.com/files/287954/original/file-20190814-136176-5rt7e5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/287954/original/file-20190814-136176-5rt7e5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=500&fit=crop&dpr=1 600w, https://images.theconversation.com/files/287954/original/file-20190814-136176-5rt7e5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=500&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/287954/original/file-20190814-136176-5rt7e5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=500&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/287954/original/file-20190814-136176-5rt7e5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=629&fit=crop&dpr=1 754w, https://images.theconversation.com/files/287954/original/file-20190814-136176-5rt7e5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=629&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/287954/original/file-20190814-136176-5rt7e5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=629&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="caption">Don’t blame the dingoes.</span>
<span class="attribution"><span class="source">Blanka Berankova/Shutterstock</span></span>
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<h2>Where did it really come from?</h2>
<p>Although marsupials are best known from Australia, they are also found in other parts of the surrounding region. The agile wallaby is <a href="https://www.iucnredlist.org/species/40560/21954106">also native to the island of New Guinea</a>, which was once joined with Australia.</p>
<p>Dogs have also been in New Guinea for <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/ece3.3487">at least as long</a> as the dingo has been in Australia. Traditionally, dogs were kept in Papuan villages, and were used to hunt game, including wallabies.</p>
<p>It came as little surprise, then, that we found <em>H. spiniger</em> on both agile wallabies and native dogs in New Guinea – and only a few decades after the first ever identification of the species.</p>
<p>So here was a more likely place in which the first transfer from wallaby to dog took place. But who took them out of New Guinea and into the wider world? </p>
<h2>Austronesian voyagers</h2>
<p>New Guinea was first colonised by humans around the same time as Australia. But since that time, compared with Australia it has had notably stronger connections with the outside world, reaching back millennia before European colonisation of Australia in 1788. </p>
<p>Around 4,000 years ago, agriculturalists known as Austronesians sailed out of Taiwan to settle several archipelagos in Oceania. With them they brought domestic species of plants and animals, including dogs.</p>
<p>By 3,000 years ago, at the latest, they <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0134497">reached New Guinea</a>. We suggest this was the crucial moment when dogs first picked up <em>H. spiniger</em>.</p>
<p>In the ensuing centuries, Austronesians went on to settle much of Indonesia, the Philippines, Melanesia and Polynesia, and coastal sections of mainland Southeast Asia. </p>
<p>They even settled as far as Madagascar, suggesting their voyages probably took them around the rim of the Indian Ocean, along the margins of India and the Middle East. </p>
<p>Dogs accompanying the migrants probably helped spread the louse, which is found almost everywhere they went. </p>
<p>This spans an enormous distance – from Hawaii to Madagascar – a testament to the ancient Austronesians’ supreme seafaring skills.</p>
<h2>New directions</h2>
<p>Our research suggests how the parasite first got around the world, but not precisely when. Its journey probably progressed at different times in different places.</p>
<p>The Austronesian diaspora established <a href="https://www.tandfonline.com/doi/abs/10.1080/03122417.2008.11681877">trade routes between the places they settled</a>, some of which spanned impressive distances across several island groups.</p>
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Read more:
<a href="https://theconversation.com/how-to-get-to-australia-more-than-50-000-years-ago-96118">How to get to Australia ... more than 50,000 years ago</a>
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<p>Later, foreign traders connected these communities with greater Asia and Africa. And in modern times, dogs continue to be transported as desirable goods themselves. </p>
<p>Trade and contact has probably led to further, possibly ongoing, dispersal of <em>H. spiniger</em>.</p>
<p>Unfortunately there are no archaeological examples that could demonstrate the louse’s early presence outside New Guinea, because this species prefers hot, humid environments.</p>
<p>A genetic approach is a better way forward. A start would be testing specimens from different parts of the world, to see when different regional populations – if they exist - branched off from one another.</p>
<p>This is particularly important in tracking its spread to the Americas, which likely occurred in recent centuries alongside European colonisation. </p>
<p>This research will help us further understand how migration, contact and trade unfolded in the prehistoric Asia-Pacific region, and how it affected the animal species – including the humblest of parasites – we see there today.</p>
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<p><em>This paper would not have been possible without the contributions of Peter Contos, the work of volunteers on the Natural History Museum’s Boopidae of Australasia digitisation project, and the contributions of the public to Wikipedia Creative Commons, for which we are grateful.</em></p><img src="https://counter.theconversation.com/content/117183/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Loukas Koungoulos receives support from an Australian Government Research Training Program scholarship, and funding from the Carlyle-Greenwell Research Fund (University of Sydney).</span></em></p>Reconsidering an old ecological conundrum comes up with a new perspective on migration, contact and trade in the Australia and Asia-Pacific region.Loukas Koungoulos, PhD Candidate, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1161582019-05-01T23:41:16Z2019-05-01T23:41:16ZCurious Kids: what’s the point of nits?!<figure><img src="https://images.theconversation.com/files/271325/original/file-20190429-194620-1x83pc9.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3273%2C2196&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Here's a close-up picture of a head louse. The eggs of the female head louse are what we call 'nits'.</span> <span class="attribution"><a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p><em><a href="https://theconversation.com/au/topics/curious-kids-36782">Curious Kids</a> is a series for children. If you have a question you’d like an expert to answer, send it to curiouskids@theconversation.edu.au You might also like the podcast <a href="http://www.abc.net.au/kidslisten/imagine-this/">Imagine This</a>, a co-production between ABC KIDS listen and The Conversation, based on Curious Kids.</em> </p>
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<blockquote>
<p><strong>What’s the point of nits?! – Connie, age 9, Nambour, Queensland.</strong></p>
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<p>Great question, Connie. I often find myself scratching my head trying to figure out the answer to that question too!</p>
<p>What we commonly call “nits” are actually the eggs of very small insects known as head lice. And head lice are found nowhere else on the planet except in human hair.</p>
<p>Head lice have adapted perfectly to life on us. They have specially designed claws at the ends of each of their six legs that are perfect for scuttling up and down the shafts of hair. </p>
<p>In fact, they’re so perfectly designed for life on our hair that once they come off they’re incredibly clumsy and have a tough time getting around at all. That’s why they’re <a href="https://theconversation.com/back-at-school-heres-how-to-keep-kids-free-of-head-lice-110344">most commonly spread between children</a> through direct head-to-head contact. Lice are tricky enough to navigate the tangle of two people’s hair. </p>
<p>Once lice have infested someone, they will climb down the hair to the scalp and bite. They need our blood to live and lay eggs. While we’ll sometimes get a reaction to their bites, that reaction is rarely as bad as they type we get from mosquitoes or ticks. Importantly, head lice don’t transmit the germs that make us sick like those other pests. At worst, we’ll just get a little itchy.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/271363/original/file-20190429-194620-19kfqvl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/271363/original/file-20190429-194620-19kfqvl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/271363/original/file-20190429-194620-19kfqvl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/271363/original/file-20190429-194620-19kfqvl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/271363/original/file-20190429-194620-19kfqvl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/271363/original/file-20190429-194620-19kfqvl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/271363/original/file-20190429-194620-19kfqvl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/271363/original/file-20190429-194620-19kfqvl.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">You can remove head lice and their eggs (nits) with a fine-tooth comb. But just one comb-out session is never enough.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/curious-kids-when-we-get-bitten-by-a-mosquito-why-does-it-itch-so-much-93347">Curious Kids: When we get bitten by a mosquito, why does it itch so much?</a>
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<hr>
<p>So, what is the point of head lice? Perhaps they don’t have a “point” at all. We like to think that all creatures play a role in the local ecosystem. We’re especially interested in insects that provide a benefit for people too. A great example are the bees and other insects that pollinate our crops that are crucial in providing food.</p>
<p>But perhaps head lice don’t play what we would traditionally see as an important role in the ecosystem. They don’t pollinate plants, they’re not food for other animals, and they don’t exactly bring joy to our lives in the way other, cuter animals do. When it comes to charismatic insects, head lice aren’t quite up there with butterflies or dragonflies!</p>
<p>I think lice see <em>us</em> as playing a role – providing them with food – but the reverse may not be true.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/271364/original/file-20190429-194609-ltn7m4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/271364/original/file-20190429-194609-ltn7m4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/271364/original/file-20190429-194609-ltn7m4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/271364/original/file-20190429-194609-ltn7m4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/271364/original/file-20190429-194609-ltn7m4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/271364/original/file-20190429-194609-ltn7m4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/271364/original/file-20190429-194609-ltn7m4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/271364/original/file-20190429-194609-ltn7m4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Lice attach their eggs to the hair with a special glue.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/curious-kids-why-do-we-have-two-kidneys-when-we-can-live-with-only-one-113201">Curious Kids: why do we have two kidneys when we can live with only one?</a>
</strong>
</em>
</p>
<hr>
<p>Perhaps we need to take a different perspective when thinking about the “point” of head lice. We marvel at the ability of plants and animals around the world to adapt to all the weird and wonderful cracks and crevices in the environment. Why shouldn’t we take inspiration from head lice being able to adapt to life on the human body?</p>
<p>Like many of the other insect pests that impact our lives, it can be hard to be sympathetic to head lice. As concern is growing about <a href="https://ecologyisnotadirtyword.com/2019/02/16/insectageddon-is-a-great-story-but-what-are-the-facts/">global insect declines</a>, I’m sure parents and carers <a href="https://theconversation.com/heres-how-you-beat-indestructible-head-lice-63594">trying to wrangle lice-infested children</a> aren’t thinking about insect conservation!</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/271366/original/file-20190429-194603-60y8kp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/271366/original/file-20190429-194603-60y8kp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/271366/original/file-20190429-194603-60y8kp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=371&fit=crop&dpr=1 600w, https://images.theconversation.com/files/271366/original/file-20190429-194603-60y8kp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=371&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/271366/original/file-20190429-194603-60y8kp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=371&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/271366/original/file-20190429-194603-60y8kp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=466&fit=crop&dpr=1 754w, https://images.theconversation.com/files/271366/original/file-20190429-194603-60y8kp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=466&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/271366/original/file-20190429-194603-60y8kp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=466&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 life-cycle of lice.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p><em>Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to curiouskids@theconversation.edu.au</em></p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=376&fit=crop&dpr=1 600w, https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=376&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=376&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=472&fit=crop&dpr=1 754w, https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=472&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/168011/original/file-20170505-21620-huq4lj.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=472&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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</figure>
<p><em>Please tell us your name, age and which city you live in. We won’t be able to answer every question but we will do our best.</em></p><img src="https://counter.theconversation.com/content/116158/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Cameron Webb and the Department of Medical Entomology, NSW Health Pathology and University of Sydney, have been engaged by a wide range of insect repellent and insecticide manufacturers to provide testing of products and provide expert advice on the biology of medically important insects. Cameron has also received funding from local, state and federal agencies to undertake research into mosquito-borne disease surveillance and management as well as risk assessment of a wide range of arthropod pests of public health importance.</span></em></p>We like to think that all creatures play a role in the local ecosystem. We’re especially interested in insects that provide a benefit for people too. But that’s not always how it is.Cameron Webb, Clinical Lecturer and Principal Hospital Scientist, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1103442019-01-28T19:15:44Z2019-01-28T19:15:44ZBack at school? Here’s how to keep kids free of head lice<p>A new school year, and another battle between bloodsucking parasites and the kids they love to live on. </p>
<p>But the real casualties are the stressed-out parents and carers trying to keep their kids free of lice.</p>
<p>Here are some tips for delaying the inevitably tricky task of lice treatment for as long as possible.</p>
<h2>Remind me, what are head lice?</h2>
<p>Head lice (<em>Pediculus capitis</em>) are insects found almost exclusively in the hair on human heads. These parasites aren’t found anywhere else on the planet. </p>
<p>They’re perfectly designed to scuttle up and down strands of hair, feeding on blood from the scalp of those infested. They typically feed about three times a day, spending up to 15 minutes on each occasion.</p>
<p>While their bites may cause some mild irritation, lice don’t spread bugs that make us sick.</p>
<p>Head lice don’t live long – not much more than a month. The adults lay eggs (commonly known as nits), which typically hatch in around a week or so. This life cycle is simple, but crucial for identifying and eradicating infestations.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/255517/original/file-20190125-108348-dvlvtd.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/255517/original/file-20190125-108348-dvlvtd.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=234&fit=crop&dpr=1 600w, https://images.theconversation.com/files/255517/original/file-20190125-108348-dvlvtd.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=234&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/255517/original/file-20190125-108348-dvlvtd.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=234&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/255517/original/file-20190125-108348-dvlvtd.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=295&fit=crop&dpr=1 754w, https://images.theconversation.com/files/255517/original/file-20190125-108348-dvlvtd.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=295&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/255517/original/file-20190125-108348-dvlvtd.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=295&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">You want to remove the adult lice, then treat again two weeks later to get rid of the newly hatched lice before they have a chance to lay more eggs.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/download/confirm/640318279?src=WQ2mkQMwfqF8OTCVCCOvZA-1-1&size=huge_jpg">By Blamb/Shutterstock</a></span>
</figcaption>
</figure>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/255516/original/file-20190125-108355-891o0o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/255516/original/file-20190125-108355-891o0o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/255516/original/file-20190125-108355-891o0o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/255516/original/file-20190125-108355-891o0o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/255516/original/file-20190125-108355-891o0o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/255516/original/file-20190125-108355-891o0o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/255516/original/file-20190125-108355-891o0o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">It’s worth investing in a lice comb.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/download/success?u=http%3A%2F%2Fdownload.shutterstock.com%2Fgatekeeper%2FW3siZSI6MTU0ODQxMTk0MywiYyI6Il9waG90b19zZXNzaW9uX2lkIiwiZGMiOiJpZGxfNDY3MzA2NjY5IiwiayI6InBob3RvLzQ2NzMwNjY2OS9odWdlLmpwZyIsIm0iOjEsImQiOiJzaHV0dGVyc3RvY2stbWVkaWEifSwiOFZVVXRXSFNKUHF3SHhkUGgyQWFaVU1teTRVIl0%2Fshutterstock_467306669.jpg&pi=41133566&m=467306669&src=WQ2mkQMwfqF8OTCVCCOvZA-1-12">By Jiri Hera</a></span>
</figcaption>
</figure>
<p>The eggs are immovably cemented to shafts of hair. These eggs, even when the lice have hatched, will remain and grow out with the hair strands. </p>
<p>This means that spotting nits <a href="http://conditions.health.qld.gov.au/HealthCondition/condition/14/165/351/head-lice">more than a centimetre or so from the scalp</a> may not require treatment at all.</p>
<p>Instead, look for the live lice moving about. This is the most reliable way to confirm an infestation. Use a special lice comb from the local pharmacy to make the search easier.</p>
<h2>How do children become infested?</h2>
<p>Head lice don’t jump or fly or swim. They move from head to head through direct contact as the strands of hair from two people make contact, creating a bridge for adventurous lice to a new world. </p>
<p>But lice can be fussy, with one study showing hairs need to be <a href="https://www.sciencedirect.com/science/article/pii/S0022202X15417713">specifically aligned</a> to allow the parasites to skip from one strand to another. </p>
<p>This is why transmission of lice from one person to another doesn’t happen as readily as urban myths suggest.</p>
<p>Sharing hats, towels, or <a href="https://onlinelibrary.wiley.com/doi/full/10.1046/j.1365-4362.2003.01927.x">pillows</a> won’t dramatically increase the chance of picking up head lice. They’re not going to crawl <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1467-842X.2002.tb00675.x">across the classroom floor</a> either.</p>
<p>Direct head-to-head contact is the best way to share an infestation, so keep an eye out for <a href="https://www.abc.net.au/news/2017-07-12/head-lice-expert-busts-myths-about-nits/8697362">kids crowded around smartphones and tablets</a>!</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/255391/original/file-20190124-135130-toa1w5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/255391/original/file-20190124-135130-toa1w5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/255391/original/file-20190124-135130-toa1w5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/255391/original/file-20190124-135130-toa1w5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/255391/original/file-20190124-135130-toa1w5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/255391/original/file-20190124-135130-toa1w5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/255391/original/file-20190124-135130-toa1w5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Head lice may be small but they can cause big worries for parents and carers of school aged children!</span>
<span class="attribution"><span class="source">Eran Finkle/Flickr</span></span>
</figcaption>
</figure>
<p>Lice don’t necessarily have a particular predilection for clean or dirty hair. Short hair isn’t immune from infestation, but <a href="https://academic.oup.com/fampra/article/33/1/23/2450445#84322874">long hair means the chances of picking up lice are greater</a>.</p>
<p>Ensuring hair is neatly pulled back will dramatically reduce the risk of picking up head lice.</p>
<h2>Are head lice really a problem in Australia?</h2>
<p>Head lice are a problem the world over. But they are more of a nuisance than a health risk in most instances.</p>
<p>Research suggests around <a href="https://onlinelibrary.wiley.com/doi/full/10.1046/j.1365-4362.1999.00680.x">one-third of Australian primary school-aged children</a> could currently have head lice. With <a href="http://www.acara.edu.au/reporting/national-report-on-schooling-in-australia-2013/schools-and-schooling/school-numbers">more than 2.1 million primary school students in Australia</a>, that’s about 700,000 potentially infested children.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/B_RsAp542x0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The thought of head lice may be actually worse than the itchiness resulting from an actual infestation. The Australian Academy of Science provides an entertaining breakdown of why this maligned parasites cause so much stress.</span></figcaption>
</figure>
<p>It’s more difficult to control head lice than in the past. International studies indicate lice are <a href="https://academic.oup.com/jme/article/53/3/653/2222496">becoming resistant</a> to commonly used insecticide treatments. This is also likely to be a <a href="https://onlinelibrary.wiley.com/doi/full/10.1046/j.1440-0960.2000.00447.x">problem in Australia</a> but more research is needed to better understand the situation here.</p>
<p>Alternatives to traditional insecticides, such as <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/ajd.12626">botanical extracts</a>, may be more useful in the future. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/heres-how-you-beat-indestructible-head-lice-63594">Here's how you beat 'indestructible' head lice</a>
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<p>Most <a href="https://www.health.nsw.gov.au/environment/headlice/Pages/treatment.aspx">health authorities in Australia</a> recommend avoiding insecticides, and instead suggest wetting the hair (or using conditioner) and then combing the lice out. </p>
<p>Essential to eradicating head lice infestations is two treatments, each about a week apart. This ensures adult lice are killed, then any eggs remaining are allowed to hatch but those newly hatched lice are killed by the second treatment before they have an opportunity to lay more eggs.</p>
<h2>I’m itchy already!</h2>
<p>Perhaps the biggest health issue associated with head lice is the <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-4632.2011.05300.x">stress and anxiety</a> for parents and carers of infested children. </p>
<p>Even before a single louse is even spotted, finding a note from the school warning of a “lice outbreak” <a href="https://www.washingtonpost.com/news/parenting/wp/2016/04/22/how-to-combat-a-case-of-psychosomatic-lice-after-receiving-the-dreaded-letter-from-school/?noredirect=on&utm_term=.954302171a44">could be enough to trigger frantic head scratching</a>! There is even a term for this: psychosomatic itching.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/255518/original/file-20190125-108364-qezbj2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/255518/original/file-20190125-108364-qezbj2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/255518/original/file-20190125-108364-qezbj2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/255518/original/file-20190125-108364-qezbj2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/255518/original/file-20190125-108364-qezbj2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/255518/original/file-20190125-108364-qezbj2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/255518/original/file-20190125-108364-qezbj2.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">Don’t worry – head lice are annoying but they’re not harmful.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/little-girl-walking-through-her-nursery-447181969?src=rGzWkl0S3Y8Z9N89FVdc6Q-1-3">By DGLimages</a></span>
</figcaption>
</figure>
<p>Unfortunately, there are no quick fixes for getting rid of lice. And no matter what social media claims, <a href="https://www.lifehacker.com.au/2012/11/kill-lice-with-mayonnaise/">using mayonnaise</a>, <a href="https://www.dailymail.co.uk/femail/article-2723821/Mum-uses-hair-straighteners-kill-childrens-head-lice-nits.html">hair straighteners or household cleaning products</a>) is a bad idea.</p>
<p>The most important thing to remember is lice aren’t going to cause health problems, nor are they indicators of poor household hygiene or quality of care.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-to-keep-school-lunches-safe-in-the-heat-89868">How to keep school lunches safe in the heat</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/110344/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Cameron Webb and the Department of Medical Entomology, NSW Health Pathology and University of Sydney, have been engaged by a wide range of insect repellent and insecticide manufacturers to provide testing of products and provide expert advice on the biology of medically important insects. Cameron has also received funding from local, state and federal agencies to undertake research into mosquito-borne disease surveillance and management.</span></em></p>Here are some tips to beat the bite of these bloodsuckers for as long as possible.Cameron Webb, Clinical Lecturer and Principal Hospital Scientist, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/750612017-07-12T20:06:38Z2017-07-12T20:06:38ZHow infectious diseases have shaped our culture, habits and language<figure><img src="https://images.theconversation.com/files/171398/original/file-20170530-16303-1clhh37.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Bubonic plague slowed urbanisation, industrial development and economic growth in Europe for many years.</span> <span class="attribution"><span class="source">from www.shutterstock.com</span></span></figcaption></figure><p><em>This is the last article in our four-part package looking at infectious diseases and how they’ve influenced our culture and evolution. Read the other articles <a href="https://theconversation.com/au/topics/infectious-diseases-package-40443">here</a>.</em></p>
<hr>
<p>Despite being so small they can’t be seen with the naked eye, pathogens that cause human disease have greatly affected the way humans live for centuries. Many infectious diseases have been significant enough to affect how and where we live, our economies, our cultures and daily habits. And many of these effects continue long after the diseases have been eliminated.</p>
<p>Infectious diseases have changed the structure and numbers of people living in communities. </p>
<p>The European bubonic plague, or “Black Death” (1348-1350), identified by painful swollen lymph nodes and dark blotches on the skin, killed 80% of those infected. At <a href="http://www.coloradotech.edu/resources/blogs/november-2012/pandemic-2">least 20 million people died</a>, which was about two-thirds of the European population at the time. It <a href="http://www.abc-clio.com/ABC-CLIOCorporate/product.aspx?pc=A1507C">slowed urbanisation, industrial development and economic growth</a> as people left cities and reverted to rural and agricultural life. Those who survived, however, were highly sought after for work.</p>
<p>The accidental introduction of measles to Fiji (1875) by people travelling between Fiji and the West caused massive numbers of deaths in communities previously not exposed to the disease. In a few months <a href="http://jmvh.org/article/pacific-island-societies-destabilised-by-infectious-diseases/">20-25% of Fijians</a> and nearly all of the 69 chiefs died. The leadership vacuum and loss of working-age population <a href="http://jmvh.org/article/pacific-island-societies-destabilised-by-infectious-diseases/">became an opportunity</a> for the colonial government to import labourers from other nations to work in the agricultural industries.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/171402/original/file-20170530-16310-1vx7zg8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/171402/original/file-20170530-16310-1vx7zg8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/171402/original/file-20170530-16310-1vx7zg8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=417&fit=crop&dpr=1 600w, https://images.theconversation.com/files/171402/original/file-20170530-16310-1vx7zg8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=417&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/171402/original/file-20170530-16310-1vx7zg8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=417&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/171402/original/file-20170530-16310-1vx7zg8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=524&fit=crop&dpr=1 754w, https://images.theconversation.com/files/171402/original/file-20170530-16310-1vx7zg8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=524&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/171402/original/file-20170530-16310-1vx7zg8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=524&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 Plague slowed economic growth in Europe as people left the cities in droves.</span>
<span class="attribution"><span class="source">from www.shutterstock.com</span></span>
</figcaption>
</figure>
<p>In the Caribbean island Hispaniola <a href="http://web.monroecc.edu/scholarsday/SDRhome">it’s estimated</a> that within 50 years of the arrival of Columbus, his crew and their “pathogens” (like measles, influenza and smallpox), the indigenous Taino people were virtually extinct. This pattern of large death tolls among Indigenous populations in the Americas is repeated in many locations, causing loss of traditional ways of life and cultural identity, and changing the course of their history.</p>
<p>Unfortunately, introduction of an infectious disease into a susceptible population was not always accidental. “Germ warfare” was a strategy used in many colonisation and war efforts. This includes North American Indigenous populations (<a href="http://onlinelibrary.wiley.com/doi/10.1038/sj.embor.embor849/abstract">there are reports</a> of blankets from smallpox-infected corpses being deliberately distributed in the late 1700s); bodies of dead animals or humans being thrown into water supplies <a href="http://onlinelibrary.wiley.com/doi/10.1038/sj.embor.embor849/abstract">during warfare in Italy in the 12th century</a>; and saliva from rabid dogs or the blood of leprosy patients being used by the Spanish against <a href="http://onlinelibrary.wiley.com/doi/10.1038/sj.embor.embor849/abstract">French enemies in Italy in the 15th century</a>. </p>
<h2>Changing global economics</h2>
<p>Infectious diseases, as well as the search for cures, have had many influences on economies over the centuries. In 1623, the <a href="https://books.google.com.au/books/about/Quinine.html?id=K8Q53xW1ie8C&redir_esc=y">death of ten cardinals</a> and hundreds of their attendants led Pope Urban VII to declare that a cure for malaria must be found.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/171404/original/file-20170530-16306-bjcz2t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/171404/original/file-20170530-16306-bjcz2t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/171404/original/file-20170530-16306-bjcz2t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/171404/original/file-20170530-16306-bjcz2t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/171404/original/file-20170530-16306-bjcz2t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/171404/original/file-20170530-16306-bjcz2t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/171404/original/file-20170530-16306-bjcz2t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/171404/original/file-20170530-16306-bjcz2t.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">Once it was discovered quinine could treat malaria it became more valuable than gold.</span>
<span class="attribution"><span class="source">from www.shutterstock.com</span></span>
</figcaption>
</figure>
<p>This was a common risk in Rome, where <em>mala aria</em> (“bad air” from marshes thought to be its origin) had existed since late antiquity. Jesuit priests travelled from Europe to South America to learn about local treatments. <a href="https://books.google.com.au/books/about/Quinine.html?id=K8Q53xW1ie8C&redir_esc=y">In 1631, they identified quinine</a>, made from the bark of the local cinchona tree in Peru, as a cure. </p>
<p>After that discovery there was a race to control quinine in order to keep armies fighting European wars, including the Napoleonic, and attempting to capture territories. At this time quinine <a href="https://books.google.com.au/books/about/Quinine.html?id=K8Q53xW1ie8C&redir_esc=y">became a commodity more precious than gold</a>.</p>
<p>In the late 1880s Tunisia experienced severe infectious disease epidemics of cholera and typhoid, and famines, which so badly depleted its economy that it was unable to pay off its debts. This made it <a href="https://www.amazon.co.uk/Empires-Sun-Struggle-Mastery-Africa/dp/1780226187">vulnerable to French occupation</a> and then colonisation.</p>
<p>In recent times, it has been estimated that the HIV epidemic in South Africa may have <a href="https://www.cgdev.org/publication/economic-implications-epidemics-old-and-new-working-paper-54">reduced its gross domestic product (GDP) by 17%</a> (from 1997 to 2010) and that SARS cost East Asia <a href="https://www.cgdev.org/publication/economic-implications-epidemics-old-and-new-working-paper-54">around $US15 billion</a>, (0.5% of GDP).</p>
<h2>Changing the foods we eat</h2>
<p>The origins of many food taboos appear to be linked to infectious diseases. These include prohibitions on drinking raw animal blood, on sharing cooking and eating utensils and plates between meat and other foods, and on eating pork in Judaism and Islam (most likely concerned about <a href="https://www.ncbi.nlm.nih.gov/pubmed/19563636">dangerous pig tapeworms</a>).</p>
<p>Newer examples of these food exclusions that are still the norm today include:</p>
<ul>
<li><p>consumption of raw milk being illegal in many countries, to prevent spread of bovine (cow) tuberculosis</p></li>
<li><p>not eating soft cheeses when pregnant to avoid contracting listeria, which can cause miscarriages and stillbirths</p></li>
<li><p>trying to stop people licking the cake bowl because of the risk of egg-borne salmonella bacteria.</p></li>
</ul>
<h2>Adding words to our languages</h2>
<p>Many words and expressions commonly used in English have origins linked to an infectious disease. One such common phrase, used for a person who may not have symptoms of an infectious disease but can transmit it, is to call them a Typhoid Mary. In 1906 Mary Mallon, a cook, was the first healthy person identified in the USA as a carrier of the typhoid bacilli that causes typhoid fever, a serious disease for the Western world in the 19th century (but which globally exists and has often existed in poor communities). </p>
<p><a href="http://www.abc-clio.com/ABC-CLIOCorporate/product.aspx?pc=A1507C">One public health engineer traced an outbreak in Oyster Bay</a> and a path of outbreaks wherever Mary worked. In New York, she was put into isolation where she stayed until she died nearly three decades later.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/171406/original/file-20170530-16303-chzz37.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/171406/original/file-20170530-16303-chzz37.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/171406/original/file-20170530-16303-chzz37.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=473&fit=crop&dpr=1 600w, https://images.theconversation.com/files/171406/original/file-20170530-16303-chzz37.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=473&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/171406/original/file-20170530-16303-chzz37.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=473&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/171406/original/file-20170530-16303-chzz37.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=595&fit=crop&dpr=1 754w, https://images.theconversation.com/files/171406/original/file-20170530-16303-chzz37.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=595&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/171406/original/file-20170530-16303-chzz37.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=595&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Feeling ‘lousy’ comes from the poor feeling experienced when suffering a lice infestation, perhaps caused by anaemia.</span>
<span class="attribution"><span class="source">from www.shutterstock.com</span></span>
</figcaption>
</figure>
<p>Other such additions to our everyday conversations include:</p>
<ul>
<li><p>“God bless you” after someone sneezes is said as it signalled that someone was unwell, perhaps seriously. It’s credited to St Gregory the Great, although words wishing the sneezer safety from disease have been found in ancient Greek and Roman.</p></li>
<li><p>the phrase “off colour” appears to have derived from the late 1800s where a diamond and then other items that were not their natural or acceptable colour were “off colour”, or defective. It soon extended to describe being unwell.</p></li>
<li><p>feeling lousy means feeling poorly. A person infested with lice often scratches, may be anaemic from the lice feeding on their blood, and doesn’t feel well.</p></li>
</ul>
<p>The 14th-century French brought us two terms used in infectious diseases: “<em>contagion</em>” meaning touching/contact; and disease from <em>des</em> (lack of) <em>ease</em> (comfort). And the 16th-century term epidemic is from the French <em>epi</em> – among, <em>demos</em> – people.</p>
<p>So pathogens evolve with us and have shaped our lives and will remain one of the forces that we adapt to as we progress through human history.</p>
<hr>
<p><em>Read the first three instalments in the series:</em></p>
<p><em><a href="https://theconversation.com/four-of-the-most-lethal-infectious-diseases-of-our-time-and-how-were-overcoming-them-78101">Four of the most lethal infectious diseases of our time and how we’re overcoming them</a></em></p>
<p><em><a href="http://theconversation.com/how-infectious-diseases-have-driven-human-evolution-75057">How infectious diseases have driven human evolution</a></em></p>
<p><em><a href="http://theconversation.com/how-we-change-the-organisms-that-infect-us-74625">How we change the organisms that infect us</a></em></p><img src="https://counter.theconversation.com/content/75061/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Maxine Whittaker 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>Despite being so small they can’t be seen with the naked eye, pathogens that cause human disease have greatly affected the way humans live for centuries.Maxine Whittaker, Dean, Public Health, Medical and Veterinary Sciences, James Cook UniversityLicensed as Creative Commons – attribution, no derivatives.