Hello, and welcome back to Everyday Science.<\/p>\n
As someone used to writing about medical matters, I\u2019m not usually squeamish. But with this week\u2019s topic, I may have reached my limits.<\/p>\n
It concerns a microscopic mite that lives on the human face. It dwells in hair follicles, such as those of the eyelashes and other facial hairs, or inside tiny skin glands.<\/p>\n
New FeatureIn ShortQuick Stories. Same trusted journalism.<\/p>\n
Conventional wisdom is that these mites, called Demodex, are usually harmless, and probably do us a favour by eating up dead skin cells and oil.<\/p>\n
But dig a little deeper and it seems that these creatures might be the unsuspected cause of a host of medical conditions, including itchy eyes, dry eyes and facial rashes and spots.<\/p>\n
Read on only if you have a strong stomach, because the more you learn about Demodex, the more unfair it seems that we put up with them. <\/p>\n
\u201cThey really are disgusting,\u201d said Professor Alex M\u00fcntz, head of the Institute of Optometry at the University of Applied Sciences and Arts Northwestern Switzerland.<\/p>\n
Face parasites that emerge at night<\/p>\n
Demodex mites have been known about since the 1800s. But they were long thought to be just one of the larger members of the diverse ecosystem of microscopic organisms that live on us and in us, which also include bacteria, viruses and fungi.<\/p>\n
The mites are sensitive to light and so spend daytime burrowed deep in the skin\u2019s glands or hair follicles.<\/p>\n
At night they emerge, feed and mate, before scurrying back under cover. As the adults have no anus, they simply get bigger as they age, before dying after a few weeks. Then, their bodies disintegrate and release their waste.<\/p>\n
Unpleasant as this sounds, in most people, the mites seem to be harmless passengers. But in some, for reasons that are not clear, they grow too numerous \u2013 and that\u2019s when the problems start.<\/p>\n
When there is overgrowth of mites in the eyelash follicles, it can cause itchy and inflamed eyelids, known as blepharitis.<\/p>\n
Optometrists look out for crusty material on the lashes, which is the remains of their dead bodies and undigested food. The telltale sign of Demodex is that this waste forms stubby cylinders around individual lashes, presumably caused by the debris slowly elongating down the lash over time.<\/p>\n
If there are too many mites in glands within the eyelids, this blocks their release of oil that normally helps keep the eyes moist. That\u2019s why dry eyes can be another impact of mite overgrowth.<\/p>\n
![\"A](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/01\/SEI_282731177.jpg\")
Rosacea can be a distressing condition, and it might be caused by mites (Photo: Olga Shefer\/Getty)<\/p>\n
Mites within glands on the skin, particularly on the cheeks, can be a cause of rosacea, when skin becomes red, dry and inflamed. Severe cases can involve pimples and over time, fine \u201cbroken\u201d veins develop.<\/p>\n
Rosacea is usually said to be caused by stress, sun exposure or alcohol. But a decade ago, research showed that people with rosacea have 10 times as many mites on their face as those without the condition<\/a>.<\/p>\n The symptoms may result from the immune system reacting to the mites, or bacteria they carry, or just from them blocking up skin pores.<\/p>\n While it is still unclear if Demodex are a cause of rosacea or are just able to multiply more easily in damaged skin, dermatologists are increasingly recommending treatments that target the mites for people with rosacea.<\/p>\n There is a wide range of options for killing off these creatures \u2013 they include ointments or tablets of anti-parasitic drugs, including ivermectin \u2013 once thought able to prevent Covid.<\/p>\n If optometrists suspect someone\u2019s eye problems are caused by Demodex, they may first recommend eyelid wipes containing tea tree oil, a substance that is toxic to the bugs \u2013 although they can sting.<\/p>\n The key is to use them just before sleep, so when the mites come out at night, it gets on their feet, said Professor Etty Bitton, chief of the dry eye clinic at the University of Montreal. \u201cThey bring it back to the follicle, and it affects them and their friends,\u201d she said.<\/p>\n People should never try to make their own eye wipes from tea tree oil, because if not diluted enough, it can burn the eyes, she added.<\/p>\n Overlooked cause of medical conditions<\/p>\n You might think these treatments make Demodex a problem that is easily fixed. But people who are plagued by rosacea or dry eyes, for instance, may treat the symptoms without seeking help for the problem\u2019s root cause.<\/p>\n Some health staff aren\u2019t yet aware that the mites may cause or contribute to so many conditions. The NHS website on rosacea<\/a>, for instance, doesn\u2019t mention them.<\/p>\n Even Demodex experts aren\u2019t sure just how often such problems are caused by overgrowth of the mites \u2013 as so much is still unclear. For instance, published estimates for how common it is for people to have any Demodex on their face range from 10 to 90 per cent.<\/p>\n The mites are harder to study than other microorganisms. Gut bacteria can be grown in a dish in the lab, and their numbers easily measured in stool samples. Demodex, by contrast, don\u2019t live for long when off the body, and there is no standardised way of gauging how many are present on someone\u2019s eyes or face.<\/p>\n \u201cWe don\u2019t know the range of infestation in the human population. It\u2019s very difficult to quantify how much somebody\u2019s Demodex burden is,\u201d said Professor James Coulson, a pharmacologist at Cardiff University.<\/p>\n One option is to pull out eyelashes to examine them, but this often leaves mites behind or flicks them in the air.<\/p>\n Optometrists can view the eyes through a special microscope called a slit lamp, but remember, the tiny beasts disappear under bright light. Instead, the distinctive cylinders of waste material can be counted, but this is a crude proxy for mite numbers, and might also depend on how often someone washes their face.<\/p>\n M\u00fcntz has recently reported a way to see the tail ends of the mites sticking out of the follicles<\/a>. <\/p>\n While viewing the eye through a slit lamp, he gets rid of the cylinders of waste by pulling them down the lash with tweezers and then gently pulls the lash sideways. \u201cI was able count the number of butts sticking out,\u201d he said. \u201cThat was the first direct, objective method of diagnosing Demodex.\u201d<\/p>\n There are claims the mites may contribute to other conditions. A pharmacist in Cardiff, Diana Senior-Fletcher, has recently proposed they may also cause conditions such as rhinitis, when people have a blocked or runny nose with no obvious cause, and asthma. <\/p>\n She says the inflammation involved in these conditions may be caused by the immune system reacting to the mites. They are being overlooked as a potential cause of disease, she said.<\/p>\n \t\tYour next read<\/p>\n Senior-Fletcher recently published a series of cases<\/a> of people who had cured themselves of conditions such as dry eyes and rhinitis, in the journal, Frontiers in Allergy. They used an unorthodox method of killing Demodex \u2013 applying Vaseline to the eyelashes every night for four weeks, thought to work by trapping the creatures in goo<\/a>.<\/p>\n But randomised trials are still needed to prove the approach is safe and effective, and anyone suspecting they have a Demodex problem should seek help from a health professional, said Senior-Fletcher.<\/p>\n On the bright side, M\u00fcntz says that for most, basic hygiene measures are probably enough to keep the creatures under control \u2013 like washing our face in the morning with soap and water. \u201cIt\u2019s surprising how many people don\u2019t do that,\u201d he said.<\/p>\n I\u2019ve been watching<\/p>\n If you like Stranger Things, you might also like a dark sci-fi TV series called, appropriately, Dark. It is set in a German town, whose economy and landscape is dominated by a nuclear power plant, which may or may not be connected to some mysterious disappearances.<\/p>\n That\u2019s not the only similarity with Stranger Things \u2013 several of the key characters are teenagers, and it is set in two time periods \u2013 the present day and the 1980s. In the earlier timeframe, the frequent 1980s cultural references, like Rubik cubes and Sony Walkmans, can feel a little forced, but that\u2019s my only gripe \u2013 apart from just how scary it is for a wimp like me. I can\u2019t watch this without a cushion at the ready.<\/p>\n","protected":false},"excerpt":{"rendered":"Don’t have nightmares, but some horrible creatures come out on to your face at night – and doctors…\n","protected":false},"author":2,"featured_media":397727,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[8916,59,102,80994,2458,4016,56,54,55],"class_list":{"0":"post-397726","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-health","8":"tag-eyesight","9":"tag-gb","10":"tag-health","11":"tag-parasite","12":"tag-skincare","13":"tag-subscriber-newsletter","14":"tag-uk","15":"tag-united-kingdom","16":"tag-unitedkingdom"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/397726","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=397726"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/397726\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/397727"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=397726"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=397726"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=397726"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n\t\t\t![\"Article](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/01\/1769730848_463_SEI_282471647_dca800-e1769527402370.jpg\")
<\/a><\/p>\n