tag:theconversation.com,2011:/us/topics/allergic-rhinitis-20471/articlesAllergic rhinitis – The Conversation2023-10-25T23:22:10Ztag:theconversation.com,2011:article/2152652023-10-25T23:22:10Z2023-10-25T23:22:10ZHello hay fever – why pressing under your nose could stop a sneeze but why you shouldn’t<figure><img src="https://images.theconversation.com/files/555215/original/file-20231023-17-cv1ic1.jpg?ixlib=rb-1.1.0&rect=32%2C24%2C5431%2C3612&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/young-pretty-woman-sneezing-front-blooming-1357485674">Shutterstock</a></span></figcaption></figure><p>If you have <a href="https://theconversation.com/sniffles-sneezing-and-cough-how-to-tell-if-its-a-simple-allergy-rather-than-the-virus-139657">hay fever</a>, you’ve probably been sneezing a lot lately. </p>
<p>Sneezing is universal but also quite unique to each of us. It is a protective reflex action outside our conscious control, to remove irritants from inside our nose. </p>
<p>The <a href="https://www.healthline.com/health/holding-in-a-sneeze">pressure in the airways</a> during a sneeze is more than 30 times greater than heavy breathing during exercise. Estimates of how fast a sneeze travels range from <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0059970">5 metres a second</a> to <a href="https://pubmed.ncbi.nlm.nih.gov/19617285/">more than 150 kilometres per hour</a>. </p>
<p>You can sometimes stop a sneeze by holding your nose or pressing underneath it. This is related to the <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/gate-control-theory">gate control theory of pain</a> and the idea you can change neural responses with external stimulation. But given the velocity of a sneeze, it might not be a good idea to stop it after it has started.</p>
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Read more:
<a href="https://theconversation.com/how-do-hay-fever-treatments-actually-work-and-whats-best-for-my-symptoms-213071">How do hay fever treatments actually work? And what's best for my symptoms?</a>
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<h2>An involuntary reflex</h2>
<p>A sneeze is initiated when sensory nerves in our nose are <a href="https://journals.sagepub.com/doi/10.1177/1753465809340571?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%20%200pubmed">stimulated by an irritant</a> such as allergens, viruses, bacteria or even fluid. </p>
<p>The sensory nerves then carry this irritant information to the brain. </p>
<p>When a threshold amount of irritant signals reach the brain, the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2077498/">sneeze reflex is triggered</a>. A sneeze first involves a deep intake of breath and a <a href="https://www.scientificamerican.com/article/why-do-we-sneeze/">build-up of pressure inside the airways</a>. This is then followed by <a href="https://www.healthline.com/health/back-pain/back-pain-when-sneezing#sneezing-as-a-cause">contraction of the diaphragm</a> and rib muscles, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2077498/">reflex closing of the eyes</a> and a strong exhalation. </p>
<p>These are the “ah” and the “tchoo” phases of a sneeze. </p>
<p>On the exhalation of a sneeze, your tongue is lifted to the roof of your mouth. This <a href="https://www.atsjournals.org/doi/10.1164/rccm.202004-1263PP">closes off the back of the mouth</a> so the air is forced mostly through your nose. The air expelled through the nose flushes out the irritants that caused the sneeze. The “tch” sound of a sneeze is the reflexive touching of the tongue to the roof of your mouth.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/555213/original/file-20231023-29-qg8qm0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="woman hold hand up to nose and looks about to sneeze" src="https://images.theconversation.com/files/555213/original/file-20231023-29-qg8qm0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/555213/original/file-20231023-29-qg8qm0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/555213/original/file-20231023-29-qg8qm0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/555213/original/file-20231023-29-qg8qm0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/555213/original/file-20231023-29-qg8qm0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/555213/original/file-20231023-29-qg8qm0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/555213/original/file-20231023-29-qg8qm0.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">Activating the trigeminal touch nerve, can overwhelm the sneeze reflex.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-woman-allergy-sneezing-girl-feeling-2057416385">Shutterstock</a></span>
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<h2>The trigeminal nerves</h2>
<p>The trigeminal nerves are the <a href="https://my.clevelandclinic.org/health/body/21998-cranial-nerves">largest of our 12 pairs of cranial nerves</a> and the largest sensory nerves in the body. </p>
<p>The left and right trigeminal nerves carry sensory information from the face to the brain. This includes touch, pain and irritation sensory information from the facial skin and from inside the nose and mouth. Within each trigeminal nerve are thousands of individual nerve branches that each carry a <a href="https://journals.sagepub.com/doi/full/10.1177/1744806920901890">specific type of sensory information</a>. </p>
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<h2>Sensory nerves communicate in the spinal cord</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/555217/original/file-20231023-25-1lg691.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="drawing of face with nerves labelled" src="https://images.theconversation.com/files/555217/original/file-20231023-25-1lg691.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/555217/original/file-20231023-25-1lg691.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=631&fit=crop&dpr=1 600w, https://images.theconversation.com/files/555217/original/file-20231023-25-1lg691.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=631&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/555217/original/file-20231023-25-1lg691.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=631&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/555217/original/file-20231023-25-1lg691.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=792&fit=crop&dpr=1 754w, https://images.theconversation.com/files/555217/original/file-20231023-25-1lg691.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=792&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/555217/original/file-20231023-25-1lg691.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=792&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">Henry Gray’s anatomical illustration of the trigeminal nerve.</span>
<span class="attribution"><a class="source" href="https://upload.wikimedia.org/wikipedia/commons/8/83/Gray778.png">Gray's Anatomy/Wikimedia Commons</a></span>
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<p>Sensory nerves travel to the brain via the spinal cord. The sensory nerves that carry pain and irritant signals are narrow, whereas those that carry touch information are wider and faster. </p>
<p>In the spinal cord, these nerves communicate with each other via interneurons before sending their message to the brain. The interneurons are the “gates” of the <a href="https://www.physio-pedia.com/Gate_Control_Theory_of_Pain#:%7E:text=and%20trigger%20%E2%80%A2-,Introduction,be%20let%20through%20or%20restricted.">gate control theory of pain</a>.</p>
<p>A nerve carrying a pain signal tells the interneuron to “open the gate” for the pain signal to reach the brain. But the larger nerves that carry touch information can “close the gate” and block the pain messages getting to the brain.</p>
<p>This is why rubbing an injured area can reduce the sensation of pain. </p>
<p><a href="https://www.frontiersin.org/articles/10.3389/fphys.2018.01037/full">One study</a> showed stimulating the trigeminal nerves by moving the jaw reduced tooth pain. We can observe this in action when babies instinctively <a href="https://chaimommas.com/2013/11/05/what-to-expect-with-teething-and-tooth-development-chart/">bite on things or pull their ear</a> when they are teething. These actions can stimulate the trigeminal touch nerves and reduce pain signals via the gate control mechanism.</p>
<h2>So does putting your finger under your nose stop a sneeze?</h2>
<p>There are <a href="https://www.healthline.com/health/how-to-stop-sneezing">many suggestions</a> of how to stop a sneeze. These include pulling your ear, putting your tongue to the roof of your mouth or the back of your teeth, touching your nose, or even sticking your finger in your nose. </p>
<p>All of these stimulate the trigeminal touch nerves with the goal of telling the interneurons to “close the gate”. This can block the irritant signals from reaching the brain and triggering a sneeze.</p>
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Read more:
<a href="https://theconversation.com/forget-nose-spray-good-sex-clears-a-stuffy-nose-just-as-effectively-and-is-a-lot-more-fun-167901">Forget nose spray, good sex clears a stuffy nose just as effectively — and is a lot more fun</a>
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<h2>But should you stop a sneeze?</h2>
<p>What if an irritant in your nose has triggered a sneeze response, but you’re somewhere it might be considered inappropriate to sneeze. Should you stop it? </p>
<p>Closing your mouth or nose during a sneeze increases the pressure in the airways <a href="https://pubmed.ncbi.nlm.nih.gov/26914240/">five to 20 times more than a normal sneeze</a>. With no escape, this <a href="https://journals.sagepub.com/doi/10.1177/1945892418823147#:%7E:text=The%20high%20Valsalva%20pressure%20generated,to%20all%20people%20who%20sneeze.">pressure has to be transmitted elsewhere</a> and that can damage your eyes, ears or blood vessels. Though the risk is low, brain aneurysm, ruptured throat and collapsed lung have been <a href="https://www.healthline.com/health/holding-in-a-sneeze#can-holding-a-sneeze-kill-you">reported</a>. </p>
<p>So it’s probably best to try and prevent the sneeze reflex by treating allergies or addressing irritants. Failing that, embrace your personal sneeze style and <a href="https://theconversation.com/handkerchief-or-tissue-which-ones-better-for-our-health-and-the-planet-213065">sneeze into a tissue</a>. </p>
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Read more:
<a href="https://theconversation.com/handkerchief-or-tissue-which-ones-better-for-our-health-and-the-planet-213065">Handkerchief or tissue? Which one's better for our health and the planet?</a>
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<img src="https://counter.theconversation.com/content/215265/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The trigeminal nerve is at the heart of the sneeze reflex. But stopping a sneeze once triggered can increase its force and redirect pressure in dangerous ways.Theresa Larkin, Associate professor of Medical Sciences, University of WollongongJessica Nealon, Lecturer in Medical Sciences (Neuroscience), University of WollongongLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2130712023-09-20T05:57:51Z2023-09-20T05:57:51ZHow do hay fever treatments actually work? And what’s best for my symptoms?<figure><img src="https://images.theconversation.com/files/549215/original/file-20230920-21-6mbsm0.jpg?ixlib=rb-1.1.0&rect=9%2C224%2C6221%2C3895&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/ill-upset-african-woman-blowing-running-1444224848">Shutterstock</a></span></figcaption></figure><p>Spring has sprung and many people are welcoming longer days and more time outdoors. But for <a href="https://www.aihw.gov.au/reports/chronic-respiratory-conditions/allergic-rhinitis-hay-fever/contents/allergic-rhinitis">almost one in five Australians</a>, spring also brings the misery of watery, itchy red eyes, a runny, congested nose, and sneezing. </p>
<p>Hay fever (also known as allergic rhinitis) is caused when an allergen enters the nose or eyes. Allergens are harmless airborne substances the body has incorrectly identified as harmful. This triggers an immune response, which leads to the release of inflammatory chemicals (mediators) – one of which is histamine.</p>
<p>Allergens that trigger hay fever differ from person to person. Common seasonal allergens include tree, grass and weed pollens (year-round allergens include dust mites, mould and pet dander). It’s now <a href="https://www.sciencedirect.com/science/article/pii/S132602002302191X">pollen season</a> in many parts of Australia, with pollen counts at their highest and hay fever cases surging. </p>
<p>So what medicines can prevent or reduce hay fever symptoms, and how do they work?</p>
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Read more:
<a href="https://theconversation.com/do-i-have-covid-or-hay-fever-heres-how-to-tell-188030">Do I have COVID or hay fever? Here’s how to tell</a>
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<h2>Antihistamines</h2>
<p>Knowing the release of histamine is a cause of hay fever symptoms, it’s unsurprising that <em>anti</em>-histamines are one of the most frequently recommended medicines to treat hay fever. </p>
<p>Antihistamines block histamine from binding to histamine receptors in the body and having an effect, reducing symptoms.</p>
<p>In Australia, we broadly have two types. The older sedating (introduced in the <a href="https://www.tga.gov.au/news/safety-alerts/first-generation-antihistamines-winter-warning">1940s</a>) and newer, less-sedating (introduced in the 1980s) antihistamines. </p>
<p>Less-sedating antihistamines used to treat allergic rhinitis include bilastine (Allertine), cetirizine (Zyrtec), loratadine (Claratyne) and fexofenadine (Telfast). Bilastine, which came onto the Australian market only last year, is only available from a pharmacy, on recommendation from a pharmacist. The others have been around longer and are available at supermarkets and in larger quantities from pharmacies. Cetirizine is the <a href="https://www.tga.gov.au/resources/publication/scheduling-decisions-interim/scheduling-delegates-interim-decisions-and-invitation-further-comment-accsacms-november-2016/35-cetirizine-hydrochloride#:%7E:text=Risks%20of%20cetirizine%20hydrochloride%20use,significant%20at%20the%20proposed%20doses.">most likely</a> (of the less-sedating antihistamines) to cause sedation.</p>
<p>The older sedating antihistamines (such as promethazine) cross the blood-brain barrier, causing drowsiness and even brain fog the next day. They have lots of side effects and potential drug interactions, and as such have little place in the management of hay fever. </p>
<p>The newer less-sedating antihistamines are <a href="https://australianprescriber.tg.org.au/articles/antihistamines-and-allergy.html#:%7E:text=Less%20sedating%20antihistamines%20are%20equally,an%20ongoing%20good%20safety%20profile">equally effective</a> as the older sedating ones.</p>
<figure class="align-center ">
<img alt="Woman with red eyes touches her face" src="https://images.theconversation.com/files/549218/original/file-20230920-29-y20eo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/549218/original/file-20230920-29-y20eo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/549218/original/file-20230920-29-y20eo4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/549218/original/file-20230920-29-y20eo4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/549218/original/file-20230920-29-y20eo4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/549218/original/file-20230920-29-y20eo4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/549218/original/file-20230920-29-y20eo4.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">
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<span class="caption">Hay fever can cause watery, itchy red eyes.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/closeup-on-young-woman-inflamed-eyes-2271555335">Shutterstock</a></span>
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<p>Antihistamines are usually taken orally (as a tablet or solution) but there are also topical preparations such as nasal sprays (azelastine) and eye drops. Antihistamine nasal sprays have <a href="https://www.sciencedirect.com/science/article/abs/pii/S108112061000743X">equal to or better efficacy</a> than oral antihistamines.</p>
<p>The individual response to antihistamines varies widely. For this reason, you may need to trial several different types of antihistamines to see which one works best for you.</p>
<p>Increasing the dose of an antihistamine, or combining an oral and topical antihistamine, does not provide any additional benefit. Paying extra for a brand name doesn’t offer any more or less effect than the generic (both have the same active ingredient and are <a href="https://www.tga.gov.au/news/news/generic-prescription-medicines-fact-sheet">bioequivalent</a>, which means they have the same outcomes for patients).</p>
<h2>Steroid nasal sprays</h2>
<p>If your symptoms don’t improve from antihistamines alone, a nasal spray containing a corticosteroid is often recommended. </p>
<p>Corticosteroids prevent the release of several key chemicals that cause inflammation. How they work is complex: in part, corticosteroids “turn off” the production of late phase inflammatory mediators (cytokines and chemokines). This reduces the future release of more inflammatory mediators, which reduces inflammation.</p>
<p>Corticosteroids and antihistamines have different mechanisms of action. Research shows corticosteroid nasal sprays are <a href="https://journals.sagepub.com/doi/full/10.2500/ajra.2016.30.4397">more effective</a> than antihistamines in controlling an itchy, runny, congested nose. But when instilled into the nose, corticosteroids <a href="https://aao-hnsfjournals.onlinelibrary.wiley.com/doi/10.1016/j.otohns.2007.10.027">also reduce</a> the eye symptoms of hay fever. </p>
<p>There are also nasal sprays that contain both an antihistamine and corticosteroid. </p>
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<strong>
Read more:
<a href="https://theconversation.com/sneezing-with-hay-fever-native-plants-arent-usually-the-culprit-190336">Sneezing with hay fever? Native plants aren't usually the culprit</a>
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<p>While there are a range of corticosteroid nasal sprays containing different active ingredients, a large study published this year shows they are all <a href="https://www.frontiersin.org/articles/10.3389/fphar.2023.1184552/full">about as effective as each other</a>, and work best when they have been taken for several days. </p>
<h2>Sodium cromoglycate</h2>
<p>Another medicine used to treat hay fever symptoms is sodium cromoglycate, which is available as an eye drop and over-the-counter in pharmacies. </p>
<p>This medicine is known as a mast cell stabiliser. As the name suggests, it stabilises or prevents mast cells from breaking down. When mast cells break down, they release histamine and other chemicals that cause inflammation. </p>
<p>This eye drop is both a preventative and treatment medicine, usually used before allergies strike. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9375451/">Evidence shows</a> it is effective at reducing the symptoms of allergic conjunctivitis (eye inflammation from allergies). </p>
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<img alt="Man blows nose at pharmacy check out" src="https://images.theconversation.com/files/549220/original/file-20230920-15-ow0w0v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/549220/original/file-20230920-15-ow0w0v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/549220/original/file-20230920-15-ow0w0v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/549220/original/file-20230920-15-ow0w0v.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/549220/original/file-20230920-15-ow0w0v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/549220/original/file-20230920-15-ow0w0v.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/549220/original/file-20230920-15-ow0w0v.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">
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<span class="caption">If you’re not sure where to start, your pharmacist or prescriber can talk you through your options.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-pharmacist-suggesting-medical-drug-buyer-102268021">Shutterstock</a></span>
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<h2>Decongestants</h2>
<p>Decongestants constrict blood vessels. They can be taken orally, administered as a nasal spray, or instilled into the eyes. When administered into the eyes it will reduce redness, and when administered into the nose, it will stop it from running. </p>
<p>However, decongestants should be used for a short duration only and are not for long term use. In fact, if a nasal spray decongestant is used for more than five days, you can experience something called “rebound congestion”: a severe stuffy nose. </p>
<h2>Saline</h2>
<p>Saline (saltwater) nasal sprays or irrigation products are also available to flush out the allergens and provide hay fever relief. While there are not many studies in the area, there is evidence that saline irrigation <a href="https://www.cochrane.org/CD012597/ENT_nasal-saline-allergic-rhinitis#:%7E:text=Saline%20irrigation%20may%20reduce%20patient,any%20outcomes%20beyond%20three%20months">may reduce hay fever symptoms</a>. Saline is safe and is not associated with adverse effects.</p>
<p>If you’re suffering from hay fever symptoms and unsure what to try, talk to your prescriber or pharmacist, who can guide you through the options and identify the best one for your symptoms, medical conditions and medicines.</p>
<p>Allergen immunotherapy (or allergen shots) is another option hay fever sufferers <a href="https://www.allergy.org.au/patients/allergy-treatments/allergen-immunotherapy-faqs">may discuss</a> with their doctors. However it’s not a quick fix, with therapy taking three to five years.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/im-considering-allergen-immunotherapy-for-my-hay-fever-what-do-i-need-to-know-190408">I’m considering allergen immunotherapy for my hay fever. What do I need to know?</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/213071/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mary Bushell 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>Struggling with watery, itchy red eyes and a runny, congested nose? Here are your options for hay fever treatment.Mary Bushell, Clinical Assistant Professor in Pharmacy, University of CanberraLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1679012021-09-17T06:23:32Z2021-09-17T06:23:32ZForget nose spray, good sex clears a stuffy nose just as effectively — and is a lot more fun<figure><img src="https://images.theconversation.com/files/421779/original/file-20210917-17-187fxxo.jpg?ixlib=rb-1.1.0&rect=28%2C18%2C6225%2C4150&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/young-couple-suffering-colds-bed-144662084">Shutterstock</a></span></figcaption></figure><p>Medical news is full of stories about promising new treatments for challenging conditions, or for additional health benefits of routine behaviours and habits. Who doesn’t want to feel good about <a href="https://edition.cnn.com/2021/08/27/health/coffee-heart-benefits-wellness/index.html">drinking coffee</a> or eating <a href="https://www.hopkinsmedicine.org/health/wellness-and-prevention/the-benefits-of-having-a-healthy-relationship-with-chocolate">chocolate</a>?</p>
<p>In this rich vein, a <a href="https://doi.org/10.1177/0145561320981441">study</a> by German and British researchers published earlier this year — which just <a href="https://www.improbable.com/2021-ceremony/winners/">won the Ig Nobel prize for medicine</a> — suggests orgasmic sex can clear nasal congestion as well as a nasal decongestant. </p>
<p>The Ig Nobels are awarded to “honour achievements that first make people laugh, and then make them think”, with a <a href="https://www.improbable.com/2021-ceremony/ig-nobel-prizes/">ceremony</a> at Harvard University and Nobel laureates among those handing out prizes. </p>
<p>This year’s winner deserves critical appraisal before deciding whether to prescribe orgasm for consenting partners with stuffy noses. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/sniffles-sneezing-and-cough-how-to-tell-if-its-a-simple-allergy-rather-than-the-virus-139657">Sniffles, sneezing and cough? How to tell if it's a simple allergy rather than The Virus</a>
</strong>
</em>
</p>
<hr>
<h2>A small but well-formed study</h2>
<p>When we critically appraise research it’s important to look at “<a href="https://d1wqtxts1xzle7.cloudfront.net/61300981/Internal_validity20191122-112894-pyhh3-with-cover-page-v2.pdf?Expires=1631846889&Signature=CrqHPcNizuEcQiEuJ0pHgcV5CD4YSmAax5j1AcbilVVq%7E3kPAt9sPNGWdFYPUrzMRk45YnmGNoolFSBVJcsYVPtjzbHfCBKBewVMQGh8KYvngbiQduIeZuHU6UhOVjkh2UVGPxrlc%7EeH5wcMmyHsSeMh%7Ewmhp7LnfKAjfroqwdKNGaOksBJzW9Kp0t9NKzAJ7XAo%7E81sq9uJLLbv9F9Y6bG%7EPCXrTV4nQ4wITSIJhiz%7ENg3j%7Eh1gv3DPK11cQU%7EdqPxPl2NHHnRNDmEvF8PFyVVr7k-5hZj2teSj4tmRSykYYof3YYNtAQG6lnklL4nqEAZlLTCDnHrFDjCQy94n4Q__&Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA">internal validity</a>” first. Could the results have been caused by other factors, such as bias due to flaws in design or how the research was conducted? The next step is to ask whether the findings have “external validity” or can be generalised to the wider population. </p>
<p>Also, with most studies that aren’t using the “<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6235704/">gold standard</a>” study design of double-blinded, randomised controlled trials, we need to consider other factors to establish cause and effect. This includes consistency with other evidence and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6289655/">biological plausibility</a> — or whether the findings tally with established understandings of our bodies. </p>
<p>The German-UK study was clearly not a double-blind study (the couples knew they were having sex) and was small in size (18 heterosexual couples), but each subject was their own “control” subject. That means each person had the intervention — sexual intercourse with orgasm — compared with a nasal decongestant spray applied the following day. </p>
<p>Nasal flow was measured at five time points: before sex, after orgasm and up to three hours afterwards. Subjects were tested with a questionnaire to determine which ones had pre-existing nose blockages over the past month. Nasal function was assessed subjectively by the participant and objectively with a portable device measuring air flow.</p>
<p>As such, this study was well-designed and conducted. That is, apart from one minor flaw: some participants were unable to focus on the device before and immediately after intercourse, leading to some missing data! </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/421772/original/file-20210917-27-1n6ixk6.jpg?ixlib=rb-1.1.0&rect=16%2C16%2C5590%2C3715&q=45&auto=format&w=1000&fit=clip"><img alt="couple in bed" src="https://images.theconversation.com/files/421772/original/file-20210917-27-1n6ixk6.jpg?ixlib=rb-1.1.0&rect=16%2C16%2C5590%2C3715&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/421772/original/file-20210917-27-1n6ixk6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421772/original/file-20210917-27-1n6ixk6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421772/original/file-20210917-27-1n6ixk6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421772/original/file-20210917-27-1n6ixk6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421772/original/file-20210917-27-1n6ixk6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421772/original/file-20210917-27-1n6ixk6.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">Some research data was lost in the afterglow.</span>
<span class="attribution"><a class="source" href="https://images.unsplash.com/photo-1585236375981-d38ad25860d3?ixlib=rb-1.2.1&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=1400&q=80">Unsplash</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/4-things-about-female-orgasms-researchers-actually-study-151015">4 things about female orgasms researchers actually study</a>
</strong>
</em>
</p>
<hr>
<h2>Going with the flow</h2>
<p>The study did find a significant improvement in nasal flow immediately after orgasm and this was of similar size to the benefit from decongestant spray used the following day. </p>
<p>However, the benefit from sexual activity was short-lived and nasal flow was back to baseline within hours. Unsurprisingly, the improved nasal flow was only seen in those with pre-existing nasal congestion.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/421778/original/file-20210917-13-1csh6y5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="nasal spray" src="https://images.theconversation.com/files/421778/original/file-20210917-13-1csh6y5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/421778/original/file-20210917-13-1csh6y5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=393&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421778/original/file-20210917-13-1csh6y5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=393&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421778/original/file-20210917-13-1csh6y5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=393&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421778/original/file-20210917-13-1csh6y5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=494&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421778/original/file-20210917-13-1csh6y5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=494&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421778/original/file-20210917-13-1csh6y5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=494&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Though effective, nasal decongestant spray is probably less fun than sex.</span>
<span class="attribution"><a class="source" href="https://image.shutterstock.com/image-photo/spray-nasal-front-black-background-260nw-777753076.jpg">Shutterstock</a></span>
</figcaption>
</figure>
<h2>Wait, there’s a connection between orgasm and noses?</h2>
<p>The research paper notes the theory of “reflex nasal neurosis” was put forward by German otolaryngologist Wilhelm Fliess, a close friend of Sigmund Freud, in 1897. Both believed neuroses were mostly caused by sexual problems. </p>
<p>Fliess <a href="https://scholar.google.com/scholar_lookup?hl=en&volume=116&publication_year=2002&pages=992-995&issue=12&author=AR+Young&title=Freud%E2%80%99s+friend+fliess">theorised</a> there were specific “genital spots” in the nose that influenced genital function. Yet his theory failed scientific scrutiny and faded into obscurity.</p>
<p>However, exercise is known to cause an improved nasal flow and this benefit <a href="https://www.tandfonline.com/doi/pdf/10.3109/00016489709113446">persists</a> for up to 30 minutes after physical activity. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/421777/original/file-20210917-27-1rnozm6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="older couple in bed" src="https://images.theconversation.com/files/421777/original/file-20210917-27-1rnozm6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/421777/original/file-20210917-27-1rnozm6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/421777/original/file-20210917-27-1rnozm6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/421777/original/file-20210917-27-1rnozm6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/421777/original/file-20210917-27-1rnozm6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/421777/original/file-20210917-27-1rnozm6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/421777/original/file-20210917-27-1rnozm6.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">Observational studies have suggested people who have more sex are happier, but that might not be the whole story.</span>
<span class="attribution"><a class="source" href="https://image.shutterstock.com/image-photo/couple-sicks-seniors-mature-people-260nw-1517677877.jpg">Shutterstock</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ive-always-wondered-why-your-nose-runs-when-its-cold-83220">I've always wondered: why your nose runs when it's cold</a>
</strong>
</em>
</p>
<hr>
<h2>The ‘take home’ message</h2>
<p>There are some limitations of the research, such as the small sample size of volunteer couples, and the timing of nasal air flow measurements. </p>
<p>But overall, the study presents some convincing evidence that orgasm improves nasal obstruction, at least for an hour or so. And, as the researchers note: “I don’t think other methods to relieve congestion are nearly as much fun as sexual activity.”</p>
<p>The Ig Nobel winners suggest further research into whether masturbation has similar benefits, or whether multiple orgasm might provide longer relief of nasal congestion.</p>
<p>So, those with nasal congestion shouldn’t throw away their decongestant sprays just yet. However, all of us can bask in the warm glow of knowing we can add another health benefit to sexual intercourse and orgasm.</p><img src="https://counter.theconversation.com/content/167901/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David King 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>A study that finds good sex gets rid of nasal congestion is definitely worthy of careful appraisal.David King, Senior Lecturer in General Practice, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1620732021-08-03T12:34:16Z2021-08-03T12:34:16ZSunny with a chance of sneezing – I’m building a tool to forecast pollen levels that will help allergy sufferers know when it’s safe to go outside<figure><img src="https://images.theconversation.com/files/414210/original/file-20210802-26-1mcpjqh.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5539%2C3820&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Advance warning of high pollen levels could help people plan their activities to avoid allergies.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/car-driver-using-asthma-inhaler-royalty-free-image/1304794626">Dobrila Vignjevic/E+ via Getty Images</a></span></figcaption></figure><p>Do flowers blossoming in spring make you miserable? Are you sworn enemies with fall bloomers like ragweed? If you suffer from pollen allergies, imagine the usefulness of a reliable pollen forecast that could help you manage your symptoms by providing an early warning when pollen conditions are bad.</p>
<p>We’re working on it! <a href="https://scholar.google.com/citations?user=sUwveOEAAAAJ&hl=en&oi=ao">As an atmospheric scientist, I study</a> the weather, climate and anything in our Earth’s atmosphere, including pollen. One in three people in the U.S. <a href="https://doi.org/10.1056/NEJMcp1412282">suffer from allergic rhinitis</a>, otherwise known as “allergies,” and pollen is the most common cause.</p>
<p>While allergic rhinitis is not curable, its symptoms can be successfully treated. Two main methods are medication and pollen avoidance. They both rely on knowing when, where and how much pollen is, and is expected to be, in the air. Many medications work best if taken before symptoms occur. Advance knowledge of pollen allows allergy sufferers to change plans in order to minimize their exposure to pollen. </p>
<p>My colleagues and I are pulling together what we know about how plant biology and meteorology affect the amount of pollen in the air, along with pollen count numbers, to build a reliable pollen forecast. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/414211/original/file-20210802-24-1jmlm3j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="magnified view of pollen grains" src="https://images.theconversation.com/files/414211/original/file-20210802-24-1jmlm3j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/414211/original/file-20210802-24-1jmlm3j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=445&fit=crop&dpr=1 600w, https://images.theconversation.com/files/414211/original/file-20210802-24-1jmlm3j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=445&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/414211/original/file-20210802-24-1jmlm3j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=445&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/414211/original/file-20210802-24-1jmlm3j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=559&fit=crop&dpr=1 754w, https://images.theconversation.com/files/414211/original/file-20210802-24-1jmlm3j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=559&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/414211/original/file-20210802-24-1jmlm3j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=559&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 view of pollen from various plants, magnified 586 times under the microscope.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/pollen-high-powered-photomicrographic-magnification-are-news-photo/179796938">BSIP/Universal Images Group via Getty Images</a></span>
</figcaption>
</figure>
<h2>Counting pollen grain by grain</h2>
<p>Allergic symptoms tend to be more severe the higher the concentration of airborne pollen. The amount of pollen in the air is constantly changing, so it would be ideal to monitor pollen in populated areas at regular frequent intervals. In the U.S., <a href="https://pollen.aaaai.org/#/">the National Allergy Bureau</a> collects, processes and distributes daily pollen concentrations from stations around the country. </p>
<p>Unfortunately, there are fewer than 90 active stations. Of these, many do not count on weekends or outside of the main pollen season. Part of the reason is that these are volunteer-run stations, and pollen monitoring requires significant time and resources.</p>
<p>Pollen is collected using a machine that sucks in air and traps pollen on sticky tape. A trained technician then processes, identifies and counts the tiny pollen grains under a microscope. During the height of pollen season, it may take a few hours for a technician to count the day’s pollen. Automated pollen monitoring systems do exist and would greatly reduce the need for human resources. But for now, these systems are either extremely expensive or have not been evaluated for accuracy.</p>
<h2>Building a forecasting model</h2>
<p>Pollen that causes allergic reactions is from <a href="http://sweetgum.nybg.org/science/glossary/glossary-details/?irn=2953">anemophilous or wind-pollinated plants</a>. Pollen grains contain the <a href="http://pollen.utulsa.edu/whatispollen.html">male sperm from the plant</a>, an essential component of plant reproduction. Anemophilous plants produce a lot of pollen because they rely on the whims of the wind to carry it to reach the female counterparts of their species to reproduce and grow new plants. The amount of pollen in the air has been rising because <a href="https://doi.org/10.1073/pnas.2013284118">climate change is lengthening the pollen season</a> and increasing how much pollen gets produced. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/414212/original/file-20210802-26-18kit17.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="backlit pollen wafts in the air around a flowering tree branch" src="https://images.theconversation.com/files/414212/original/file-20210802-26-18kit17.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/414212/original/file-20210802-26-18kit17.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/414212/original/file-20210802-26-18kit17.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/414212/original/file-20210802-26-18kit17.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/414212/original/file-20210802-26-18kit17.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/414212/original/file-20210802-26-18kit17.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/414212/original/file-20210802-26-18kit17.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"></a>
<figcaption>
<span class="caption">Certain weather conditions make it more likely to be a heavy pollen day.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/pollen-like-snow-royalty-free-image/91821142">Alkimson/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<p>Since we have access to only a limited amount of pollen count data, my colleagues and I leverage what we know about the environment to estimate the amount of pollen in the air. Generally warm, sunny, dry and windy days are correlated with high airborne pollen concentrations, and rainy and humid days with low concentrations. </p>
<p>Plants depend on water and sunlight to grow. The timing of precipitation, temperature and solar radiation can affect a plant’s development and its readiness to flower. Once the plant is ready to flower, environmental variables can determine when pollen is released, how far it travels and how long it remains in the air. </p>
<p>The <a href="https://doi.org/10.1016/j.scitotenv.2021.145590">pollen model my colleagues and I have developed</a> uses these known relationships between meteorology and pollen to estimate airborne pollen. We also include satellite images of vegetation in the model because satellites can detect greening and provide an estimate of the beginning of spring.</p>
<p>Our model can forecast pollen 1 to 14 days in advance for locations where there are pollen stations. But due to the sparsity of pollen stations, we are working on extending the model to forecast in locations with no pollen counts. In those places we use nearby pollen station data, along with localized meteorology, to estimate the pollen. </p>
<p>Although pollen reporting and forecasts do exist in the popular media, <a href="https://doi.org/10.1186/1710-1492-8-S1-A11">their pollen reports differ from observations</a>, and their forecasts are limited only to categories of trees, grasses and weeds. Our forecast can predict for specific pollen types because our model includes information about how each plant type interacts differently with the environment.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/414213/original/file-20210802-18-11a1ai0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="woman checks her phone against backdrop of windows at night" src="https://images.theconversation.com/files/414213/original/file-20210802-18-11a1ai0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/414213/original/file-20210802-18-11a1ai0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/414213/original/file-20210802-18-11a1ai0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/414213/original/file-20210802-18-11a1ai0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/414213/original/file-20210802-18-11a1ai0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/414213/original/file-20210802-18-11a1ai0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/414213/original/file-20210802-18-11a1ai0.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">Checking the pollen forecast could help you plan when to take allergy medication and how much time you’d spend outside.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/young-businesswoman-checking-smartphone-in-the-royalty-free-image/969436696">Klaus Vedfelt/DigitalVision via Getty Images</a></span>
</figcaption>
</figure>
<h2>A fine-tuned forecast in your pocket</h2>
<p>We are collaborating with medical professionals and health scientists to understand the pollen levels associated with increasing severity of allergic symptoms. Our plan is to tailor the forecast to allow patients to better manage their symptoms.</p>
<p>So far, we can accurately forecast for four of the most abundant pollen types in the U.S. only in locations with pollen stations. We are seeking funding to expand to other pollen types and other locations, and we are working on creating a platform to automate the data processing and run the forecast.</p>
<p>Ultimately, we want to provide a forecast every day during pollen season to give allergy sufferers the information they need to manage their symptoms. <a href="https://doi.org/10.1016/j.rmed.2005.05.012">Allergies are often undertreated</a> and <a href="https://doi.org/10.1111/crj.12015">knowledge about self-care is limited</a>, so a reliable pollen forecast that is easy to access – for example via an app on your phone – along with education on allergy management, could really help allergy sufferers.</p>
<p>[<em>You’re smart and curious about the world. So are The Conversation’s authors and editors.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=youresmart">You can read us daily by subscribing to our newsletter</a>.]</p><img src="https://counter.theconversation.com/content/162073/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Fiona Lo does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Scientists are building a pollen forecasting model using meteorology, botany, pollen count numbers and satellite imagery to help people plan ahead.Fiona Lo, Postdoctoral Researcher in Environmental and Occupational Health Sciences, University of WashingtonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1147222019-04-03T10:47:10Z2019-04-03T10:47:10ZPollen is getting worse, but you can make things better with these tips from an allergist<figure><img src="https://images.theconversation.com/files/267206/original/file-20190402-177199-8izsl1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A girl in a field of flowers.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/pollen-allergy-girl-sneezing-field-flowers-93088627">Alex Cofaru/Shutterstock.com</a></span></figcaption></figure><p>Blooming spring flowers signal the beginning of spring, but for millions of people, they also signal the onset of the misery: <a href="https://acaai.org/allergies/seasonal-allergies">allergy and asthma season</a>. Itchy, watery eyes; sneezing, runny nose; cough and wheezing are triggered by an overreaction of the body to <a href="https://www.aaaai.org/conditions-and-treatments/conditions-dictionary/pollen">pollen.</a></p>
<p>Every spring, trees and grasses release billions of buoyant pollen granules into the air, using the wind to disburse across the countryside in an effort to reproduce. It’s all about survival; plants that release more pollen have the survival advantage. </p>
<p>As an adult and pediatric allergist-immunologist in the Midwest, the onset of spring signals my busy season treating hundreds of patients for their seasonal allergy and asthma symptoms. If you suffer through the season, know that you are not alone. Throughout history, pollen has taken the fun out of spring for many. In modern times, however, medical science has identified practices and treatments that help. </p>
<h2>Older than the dinosaurs, as wide as the world</h2>
<p>Fossilized specimens of pollen granules have been found predating dinosaurs and alongside <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5098096/">Neanderthals</a>. </p>
<p>And, sinus and asthma symptoms and treatments are documented throughout history and across the globe. People just didn’t know exactly how to treat the symptoms, or exactly what was causing them. </p>
<p>For example, over 5,000 years ago, the Chinese used the berries of the horse tail plant, ma huang (<em>Ephedra distachya</em>), to relieve congestion and decrease mucous production associated with “<a href="http://pennstatehershey.adam.com/content.aspx?productId=107&pid=33&gid=000240">plant fever</a>” - a condition affecting people during the fall. </p>
<p>In Egypt, the “<a href="https://babel.hathitrust.org/cgi/pt?id=coo.31924073200077;view=1up;seq=11">Papyrus Ebers</a>,” written around 1650 B.C., recommended over 20 treatments for cough or difficulty breathing, including honey, dates, juniper and beer. </p>
<p>Although <a href="https://www.ncbi.nlm.nih.gov/pubmed/6757243">Homer’s “Iliad”</a> describes the loud noise of breathing in battle as “asthma,” <a href="https://www.atsjournals.org/doi/full/10.1164/ajrccm.184.12.1420b">Aretaeus of Cappadocia</a> of the second century A.D. is credited with the first clinical description more consistent with modern understanding of this condition. He wrote of those who suffered that: </p>
<p>“They open the mouth since no house is sufficient for their respiration, they breathily standing, as if desiring to draw in all the air which they possibly can inhale… the neck swells with the inflation of the breath, the precordia (chest wall) retracted, the pulse becomes small and dense,” and if the symptoms persist, the patient “may produce suffocation after the form of epilepsy.” </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/267207/original/file-20190402-177171-1xf3s40.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/267207/original/file-20190402-177171-1xf3s40.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/267207/original/file-20190402-177171-1xf3s40.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/267207/original/file-20190402-177171-1xf3s40.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/267207/original/file-20190402-177171-1xf3s40.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/267207/original/file-20190402-177171-1xf3s40.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/267207/original/file-20190402-177171-1xf3s40.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">
<figcaption>
<span class="caption">Tobacco leaves were exported to Europe for experimentation in treating the symptoms of spring time coughing and sneezing.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/tobacco-leaves-drying-shed-194524280">Jeep 2499/Shutterstock.com</a></span>
</figcaption>
</figure>
<p>By the time Columbus landed, indigenous populations in Central and South American were utilizing <a href="https://benthamopen.com/contents/pdf/TONPJ/TONPJ-4-8.pdf">ipecacuanha</a>, a root found in Brazil with expectorant and emetic properties and <a href="https://www.merriam-webster.com/dictionary/balsam">balsam</a>, which is still used in some cold remedies today. <a href="https://www.hindawi.com/journals/emi/2016/4048764/">Coca</a> and tobacco leaves, used medicinally by the Incas, were later exported to Europe for additional experimentation for the treatment of rhinitis and asthma. </p>
<p>Aside from the “plant fever” described in China, the first written description of seasonal respiratory symptoms is credited to <a href="https://www.ncbi.nlm.nih.gov/pubmed/27840475">Rhazes</a>, a Persian scholar, around 900 A.D. He described the nasal congestion that coincided with the blooming of roses, termed “rose fever.” </p>
<h2>Symptoms noticed, but no cause identified</h2>
<p>As scientific advancement was stifled during the Middle Ages, in large part due to the plague, it wasn’t until 900 years later, in 1819, that <a href="https://www.bbc.com/news/magazine-28038630">Dr. John Bostock</a> published a description of his own seasonal allergies. But he didn’t know what was causing them.</p>
<p>Having suffered from “<a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(01)99507-8/fulltext">summer catarrh</a>” since childhood, Bostock persisted in his study of the condition, despite an initial lackluster response from the medical community. </p>
<p>In the nine years between his first and second publications, he found only <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3110966/">28 additional cases</a> consistent with his own seasonal allergy symptoms, which perhaps demonstrates the lower prevalence of the condition at the time. He noted that nobility and the privileged classes were more often afflicted by seasonal allergies. This was thought to be the consequence of wealth, culture and an indoor life. </p>
<p>Societal changes with their roots in the Industrial Revolution, including increased exposure to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4829390/">air pollution, less time spent outdoors, increased pollen counts and improved hygiene</a>, all likely contributed to the increased prevalence of allergies that we continue to see today. They also helped form the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2841828/">hygiene hypothesis</a>, which states that in part decreased exposure to particular bacteria and infections could be leading to the increase in allergic and autoimmune diseases.</p>
<p>The source of seasonal symptoms at the time was also thought to be caused by the smell of new hay. This led to the coining of the term “<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3110966/">hay fever</a>.” </p>
<p>Bostock instead suspected the recurring symptoms were triggered by the summer heat, since his symptoms improved when he spent the summer on the coast. It would later became common for nobility and aristocrats to spend allergy season in coastal or mountain resorts to avoid bothersome symptoms. </p>
<h2>Identifying the true culprit</h2>
<p>Through methodical study and self-experimentation, <a href="https://hekint.org/2017/01/28/charles-harrison-blackley-the-man-who-put-the-hay-in-hay-fever/">Dr. Charles Blackley</a> identified that pollen was to blame for allergy symptoms. He collected, identified, and described various pollens and then determined their allergic properties by rubbing them into his eyes or scratching them on his skin. He then noted which ones resulted in redness and itching. This same technique is used in skin prick testing by allergists today. </p>
<p>Inspired by discoveries related to vaccination, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3651049/">Dr. Leonard Noon</a> and John Freeman prepared doses of <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3651049/">pollen extracts for injection</a> in an effort to desensitize patients with allergic rhinitis in the early 1900s. This effective treatment, called <a href="https://acaai.org/allergies/allergy-treatment/allergy-immunotherapy">allergy immunotherapy</a>, also known as allergy shots, is still used today.</p>
<p><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3667286/">Antihistamines</a> first became available in the 1940s, but they caused significant sedation. The formulations with fewer side effects that are used today have only been available since the 1980s. </p>
<h2>Pollen counts likely to grow</h2>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/267228/original/file-20190402-177184-15tteuy.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/267228/original/file-20190402-177184-15tteuy.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=453&fit=crop&dpr=1 600w, https://images.theconversation.com/files/267228/original/file-20190402-177184-15tteuy.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=453&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/267228/original/file-20190402-177184-15tteuy.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=453&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/267228/original/file-20190402-177184-15tteuy.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=569&fit=crop&dpr=1 754w, https://images.theconversation.com/files/267228/original/file-20190402-177184-15tteuy.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=569&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/267228/original/file-20190402-177184-15tteuy.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=569&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Pollen on a street in Atlanta, March 31, 2019.</span>
<span class="attribution"><span class="source">Lynne Anderson</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Though recognized by ancient civilizations, seasonal allergic rhinitis and allergic asthma have only increased in prevalence in recent history and are on the rise, now affecting <a href="https://www.aaaai.org/about-aaaai/newsroom/allergy-statistics">10 to 30 percent of the world’s population</a>.</p>
<p>Fueled by warmer temperatures and increased carbon dioxide levels, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4829390/">pollen seasons are longer, and pollen counts are higher</a>. Many experts believe this will <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4829390/">worsen</a> in the coming years due in large part to climate change.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/267209/original/file-20190402-177167-h0ncsh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/267209/original/file-20190402-177167-h0ncsh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/267209/original/file-20190402-177167-h0ncsh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/267209/original/file-20190402-177167-h0ncsh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/267209/original/file-20190402-177167-h0ncsh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/267209/original/file-20190402-177167-h0ncsh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/267209/original/file-20190402-177167-h0ncsh.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">
<figcaption>
<span class="caption">To keep you and your loved ones safe from pollen, close windows and change out of clothes exposed to pollen as soon as you come indoors.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-boy-girl-school-lunch-table-1177724560">Monkey Business Images/Shutterstock.com</a></span>
</figcaption>
</figure>
<p>What can you do? Often, those who are allergic need a multifaceted approach. </p>
<ul>
<li><p>Find out what allergens are causing your symptoms.
Take note of when your symptoms start by making a note in a calendar or planner.</p></li>
<li><p>Minimize exposure to allergens.
<a href="https://www.aaaai.org/global/nab-pollen-counts?ipb=1">Track pollen counts</a>. When pollen counts are high, keep the windows closed at home and in the car. After spending time outdoors, shower and change clothing to prevent ongoing exposure to pollen. </p></li>
<li><p>Take a pro-active approach to treating symptoms.
Starting medications before symptoms develop can prevent symptoms from getting out of control. This can also decrease the amount of medication needed overall. Long acting non-sedating antihistamines are helpful for itching and sneezing. Nasal corticosteroid sprays are more helpful for stuffy noses. </p></li>
<li><p>Consider a visit to see a <a href="https://acaai.org/locate-an-allergist">board certified allergist/immunologist</a>. She or he can help you determine which particular pollens maybe the source of your symptoms.</p></li>
<li><p>Explore the role of immunotherapy with your doctor. Immunotherapy changes the immune response through administration of small regimented doses of allergens over time. This induces a state of tolerance, eventually helping people become less allergic over time. </p></li>
</ul>
<p>While pollen season is coming, taking a multifaceted approach can provide much needed relief from the symptoms that have plagued humankind throughout the millennia.</p><img src="https://counter.theconversation.com/content/114722/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kara Wada does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Pollen is ancient, but in recent times, it’s getting worse. An allergist offers ways to manage the suffering and enjoy the spring.Kara Wada, Clinical Assistant Professor, Allergy/Immunology, The Ohio State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/974742018-06-21T08:42:48Z2018-06-21T08:42:48ZWe’re working on a more accurate pollen forecasting system using plant DNA<figure><img src="https://images.theconversation.com/files/224120/original/file-20180620-137708-1n79gp6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Hayfever.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/pollen-allergy-girl-sneezing-field-flowers-93088627?src=pmx7uDSqeZc6oRfdhaCXeQ-1-10">Alex Cofaru/Shutterstock</a></span></figcaption></figure><p>Most people enjoy the warmer, longer days that summer months bring – but plant allergy sufferers will have mixed emotions. Roughly <a href="http://erj.ersjournals.com/content/24/5/758">one in five Europeans</a> suffers from allergic reactions to tree, grass and weed pollen causing pollinosis, <a href="https://theconversation.com/explainer-what-is-hay-fever-and-why-do-you-have-it-27034">hay fever</a> and <a href="https://theconversation.com/whats-the-link-between-hay-fever-and-asthma-and-how-are-they-treated-64740">allergic asthma</a>.</p>
<p>Allergies to substances such as pollen are driven by errors in the body’s immune system, which means it mounts a response to otherwise benign substances from plants. On first exposure to pollen, the body decides if some of the otherwise harmless proteins in the pollen are dangerous. If it decides they are, the immune system produces immunoglobin E (IgE) antibodies in a process called sensitisation. </p>
<p>The next time the body is exposed to pollen, it remembers the proteins and mounts another response. The IgE antibodies detect the pollen in, or on, the body, and cause cells to release histamine and a variety of other chemicals. This <a href="https://theconversation.com/hay-fever-survival-guide-why-you-have-it-and-how-to-treat-it-34000">results in symptoms</a> ranging from itchy eyes and nose, to production of mucous, inflammation and sneezing fits. </p>
<p>But while we know that “pollen” causes this response, at present we still don’t know all the types of pollen that cause the body to react. </p>
<h2>Forecasting hay fever</h2>
<p>In the UK, a <a href="https://www.metoffice.gov.uk/public/weather/pollen-forecast/#?tab=map&map=Pollen&fcTime=1527764400&zoom=5&lon=-4.00&lat=55.71">daily pollen forecast</a> is generated by the UK Met Office in collaboration with the National Pollen and Aerobiology Unit (NPARU), to help allergy sufferers. This forecast is created using data from a network of pollen traps which operate throughout the main pollen season (March to September) and measure how many pollen grains are present on a daily basis. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/224175/original/file-20180621-137750-1dr5fn9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/224175/original/file-20180621-137750-1dr5fn9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/224175/original/file-20180621-137750-1dr5fn9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/224175/original/file-20180621-137750-1dr5fn9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/224175/original/file-20180621-137750-1dr5fn9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/224175/original/file-20180621-137750-1dr5fn9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/224175/original/file-20180621-137750-1dr5fn9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/224175/original/file-20180621-137750-1dr5fn9.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">Sweet vernal, an early flowering grass.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Pollen from different types of tree can be identified using microscopes, but grass pollen grains all look the same. As a result the pollen forecast for grasses (of which there are 150 types in the UK alone) is based on the broad, undifferentiated category of “grass”. That is despite grass pollen being the single most important outdoor aeroallergen. </p>
<p>We already know that different species of grass pollinate at different times in the year, and allergic reactions can occur at different times throughout the allergy season. What we need to figure out is whether allergies are caused by all species, specific species, or a combination of species of grasses. We also need to learn how pollen grains change in composition in time and space. While pollen is known for being very tough and is often well preserved in sediments, it can be very fragile in certain circumstances, such as bursting when in contact with rain drops. </p>
<p>To find out which grasses are linked to the allergic response, we need to know many things, such as where and when species of grass are releasing pollen. We also need to uncover how the pollen moves through the atmosphere, quantify the exposure of grass pollen species in time and space, and work out how allergies develop across broad geographical and temporal scales.</p>
<h2>The #PollerGEN project</h2>
<p>Our Natural Environment Research Council (NERC) <a href="http://pollergen.bangor.ac.uk/">PollerGEN project</a> team is now working on a way to detect airborne pollen from different species of allergenic grass. We’re also developing new pollen source maps, and modelling how pollen grains likely move across landscapes, as well as identifying which species are linked with the exacerbation of asthma and hay fever.</p>
<p>We’re going to be using a <a href="https://botanicgarden.wales/science/collections/barcode-uk/">new UK plant DNA barcode library</a>, as well as environmental genomic technologies to identify complex mixtures of tree and grass pollens from a molecular genetic perspective. By combining this information with detailed source maps and aerobiological modelling, we hope to redefine how pollen forecasts are measured and reported in the future.</p>
<p>We have just started the third year of pollen collection and hope to road test the combined forecasting methods over the next year. In the long run, our vision is to be able to provide specific pollen forecasts for grass, and unravel which species of grass pollen are most likely causing allergic responses. More broadly, we also want to provide information to healthcare professionals and charities, who can translate this information to help pollen allergy sufferers live healthier and more productive lives.</p>
<p>In the meantime, if you suffer from pollen allergies, sneeze or wheeze during spring, speak to a doctor or pharmacist to prepare an action plan. You can also get support from <a href="https://www.allergyuk.org/">Allergy UK</a>, and information about the pollen forecast from the <a href="https://www.metoffice.gov.uk/public/weather/pollen-forecast/">UK Met Office</a>.</p><img src="https://counter.theconversation.com/content/97474/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Simon Creer receives funding from the Natural Environment Research Council. </span></em></p><p class="fine-print"><em><span>Georgina Brennan 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>Unlocking the genetic code of certain grasses could help allergy sufferers.Simon Creer, Professor in Molecular Ecology, Bangor UniversityGeorgina Brennan, Postdoctoral Research Officer, Bangor UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/403182015-10-07T19:24:44Z2015-10-07T19:24:44ZWhat are allergies and why are we getting more of them?<figure><img src="https://images.theconversation.com/files/95161/original/image-20150917-7521-3ppdou.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Allergies are becoming more frequent in the western world. </span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/al-stan/3475946574/">Al Fed/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p>Allergies are reactions caused by the immune system as it responds to environmental substances that are usually harmless to most people. They may occur in response to a range of different material (called allergens), such as food, pollen, dust mites, animals, insect stings, or medicines.</p>
<p>An allergy can <a href="http://www.allergy.org.au">affect different parts of the body</a>. Allergic rhinitis, or hay fever, for instance, affects the nose and eyes, while eczema affects the skin. Food allergies affect the gut, skin, airways, lungs, and sometimes the entire body through the blood vessels. </p>
<p>Other conditions such as asthma, which affects the lungs, and eosinophilic oesophagitis, which affects the tube from the throat to the stomach, are closely related to allergy. But they have slightly different underlying causes. </p>
<h2>A range of reactions</h2>
<p>While most reactions are only mild to moderate in severity (and can be treated with antihistamines), some can be life-threatening and require emergency medical treatment. The most severe, systemic allergic reactions are known as anaphylaxis. People with known severe allergies should have an <a href="http://www.allergy.org.au">emergency management plan</a> that includes an adrenaline auto-injector for emergency use. </p>
<p>We can confirm whether someone has an allergy by doing a skin-prick testing or a blood test that checks whether their immune system has produced antibodies to an allergen. If the immune system has developed antibodies, it will remember the allergen as a potential threat and is likely to mount a strong immune response on subsequent exposure. </p>
<p>The likelihood of someone having an allergic reaction from future exposures to the allergen is determined by taking their clinical history and these test results into account. </p>
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<img alt="" src="https://images.theconversation.com/files/95141/original/image-20150917-12695-2a4xns.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/95141/original/image-20150917-12695-2a4xns.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=265&fit=crop&dpr=1 600w, https://images.theconversation.com/files/95141/original/image-20150917-12695-2a4xns.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=265&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/95141/original/image-20150917-12695-2a4xns.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=265&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/95141/original/image-20150917-12695-2a4xns.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=333&fit=crop&dpr=1 754w, https://images.theconversation.com/files/95141/original/image-20150917-12695-2a4xns.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=333&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/95141/original/image-20150917-12695-2a4xns.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=333&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">Allergic rhinitis, or hay fever, affects the nose and eyes.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/14353437@N06/4515249683/">parrchristy/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<p>In the case of food allergy, if the probability of an allergic reaction is low, people are given a food challenge. This is when increasing amounts of the offending food are administered while the person is closely observed for any signs of an allergic reaction. Of course, it can result in a reaction.</p>
<p>Allergies are becoming more frequent in Australia and the rest of the western world. <a href="http://www.allergy.org.au/">One in three people in Australia</a> will develop allergies at some time in their life. One in 20 will develop a food allergy and one in 100 will have a life-threatening allergic reaction known as anaphylaxis .</p>
<p>Hospital admissions for anaphylaxis <a href="http://www.ncbi.nlm.nih.gov/pubmed/26187235">doubled in the ten years</a> from 1994 to 2004, and were five times higher in children under five years old over the same period. This suggests the development of allergy in early life is increasing at a faster rate than in adults.</p>
<p>Children are <a href="http://www.abc.net.au/news/2015-07-15/number-of-children-hospitalised-with-food-allergies-on-the-rise/6619752">more likely to develop allergies</a> to eggs, dairy products or peanuts, while adults are more likely to develop an allergy to seafood. </p>
<h2>Possible reasons why</h2>
<p>The reasons for the rising number of allergies are not fully understood, but here are six theories.</p>
<p>1) Decreased exposure to infections or microbes – or both – in early life could lead to an increased risk of allergy. This is commonly referred to as the hygiene hypothesis, <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1838109/">first suggested in 1989</a>. <a href="http://www.ncbi.nlm.nih.gov/pubmed/21060319">Research showing</a> children who have close contact with pets or livestock and those who come from larger families are less likely to develop allergies have indirectly supported the hygiene hypothesis.</p>
<p>2) Delayed introduction of allergenic foods, such as eggs and nuts, until later in childhood could also have an impact. This is one of the most recent theories resulting from the <a href="http://www.nejm.org/doi/full/10.1056/NEJMoa1414850">LEAP study</a>, published in 2015. This randomised trial for early life peanut consumption in a population at increased risk of developing peanut allergies demonstrated that exposure to the nut early in life is protective against developing the allergy.</p>
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<img alt="" src="https://images.theconversation.com/files/95162/original/image-20150917-7517-3j4zx9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/95162/original/image-20150917-7517-3j4zx9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=385&fit=crop&dpr=1 600w, https://images.theconversation.com/files/95162/original/image-20150917-7517-3j4zx9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=385&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/95162/original/image-20150917-7517-3j4zx9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=385&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/95162/original/image-20150917-7517-3j4zx9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=483&fit=crop&dpr=1 754w, https://images.theconversation.com/files/95162/original/image-20150917-7517-3j4zx9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=483&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/95162/original/image-20150917-7517-3j4zx9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=483&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">A child with a nut allergy only has a 20% chance of the allergy resolving by the time she reaches adulthood.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/aoifemac/8424630783/">Aoife Mac/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<p>3) Different methods of preparing foods can <a href="http://www.ncbi.nlm.nih.gov/pubmed/19000582">impact the degree</a> to which they invoke an allergic response; roasting peanuts, for instance, greatly increases allergenicity while boiling reduces it. This may in part explain difference in incidence of in peanut allergy between certain countries.</p>
<p>4) Vitamin D deficiency may increase the risk to develop allergies. Several studies show that the further away you live from the equator (hence your lower level of sunlight exposure, which is needed to make Vitamin D) – or <a href="http://www.abc.net.au/health/features/stories/2013/03/07/3710140.htm">low vitamin D blood levels increase your risk</a> of developing allergies. But the value of vitamin D treatment for preventing allergies has yet to be demonstrated. </p>
<p>5) Allergies may develop after exposure to allergens, such as dairy products or nut oils in skin moisturisers, particularly on inflamed sites, such as eczema.</p>
<p>6) Altered gut bacterial species due to low-fibre diets and widespread antibiotic usage may alter the body’s immune function and create an allergy.</p>
<p>Whether your allergy improves over time often depends on the type of allergy you have. A child with eczema, for instance, will often find her eczema improves by the time she’s a teenager. But some people will have eczema even into their adult years. In contrast, a child with peanut allergy only has a 20% chance of the allergy resolving by the time she reaches adulthood.</p>
<p>While we have treatments for the symptoms of allergy, we do not yet have a cure or the ability to prevent them from developing in the first place. We also don’t have a good test for predicting food allergy, unless we feed the person the suspected food allergen. For now, the best you can do is to manage your allergy.</p><img src="https://counter.theconversation.com/content/40318/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Adam Collison receives funding from the NHMRC, Hunter Children's Research Foundation and the Thrasher Research Fund. He is an inventor on a provisional patent that describes a marker for peanut allergy.</span></em></p><p class="fine-print"><em><span>Joerg Mattes receives/received funding from the National Health&Medical Research Council, the Hunter Medical Research Institute, the Hunter Children's Research Foundation, Asthma Australia, Rebecca L. Cooper Medical Research Foundation. He is a listed inventor on a patent describing a peanut anaphylaxis blood biomarker.</span></em></p><p class="fine-print"><em><span>Rani Bhatia receives funding from the Hunter Children's Research Foundation. She is an inventor on a provisional patent that describes a marker for peanut allergy.</span></em></p><p class="fine-print"><em><span>Elizabeth Percival 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>Allergies are reactions caused by the immune system as it responds to environmental substances that are usually harmless. But we don’t yet have a cure or the ability to prevent them from developing.Adam Collison, Post Doctoral researcher - Experimental and Translational Respiratory Medicine Research Group, University of NewcastleElizabeth Percival, Staff Specialist General Paediatrician at John Hunter Children's Hospital, Newcastle, Australia. Conjoint Lecturer & PhD student, University of NewcastleJoerg Mattes, Professor&Chair of Paediatrics | HMRI, University of Newcastle, Australia | Senior Staff Specialist Paediatric Respiratory&Sleep Medicine | John Hunter Children's Hospital, Australia, University of NewcastleRani Bhatia, Senior Staff Specialist in Paediatric Allergy and Immunology at John Hunter Children's Hospital Newcastle NSW Conjoint Lecturer in Paediatrics, University of NewcastleLicensed as Creative Commons – attribution, no derivatives.