Horsehair Worms in People (Nematomorpha Infestation in Humans)

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EXCITING UPDATE! We have recently come across a new medical provider who actually believes what is going on, and has said they are happy to work with anybody experiencing these symptoms, including remotely. Please see their information by going to our resource page here and looking for “Lighthouse Complex Care”. We are not affiliated with them, and we do not receive compensation or anything else from them, we just have been impressed with how caring they are.

Horsehair worms are one of the most common parasites found in nature, and also one of the most misunderstood. Between the myths that surround them, as well as the vast claims that many make about them, this article intends to clear up any of the misinformation about horsehair worms, particularly their relationship to humans.

Photo of Horsehair Worm from Previous Article

To start with, horsehair worms (Nematomorpha) are parasites of invertebrates: mostly insects, though they have been known to take crustaceans as hosts as well. When they are not inside a host though, they prefer aquatic environments. In fact, the eggs of the horsehair worms are laid in bodies of water. And it is in this body of water that the egg hatches, releasing a microscopic larva that will then eventually be consumed by an insect. The catch is that the larva is covered by a cyst, thus protecting them from dying upon consumption. Once consumed, the cyst dissolves and the larva is free to burrow into the stomach of the insect and begin maturation.

Now, besides the myth surrounding their name, that horsehair worms actually develop in the manes of horses and fall down when the horses feed, there is a lot of misinformation regarding the parasitization of humans. We have received a lot of feedback on our articles about horsehair worms, in which we state that horsehair worms do not infect humans, stating that we should correct this, as there have been cases of humans becoming infected by horsehair worms.

To this we want to first say that we appreciate any and all feedback that our readers provide us, and we are more than happy to clear up this once and for all. Secondly, while we maintain the stance that horsehair worms do not purposely infect humans, we agree that they can indeed end up in humans, and we have research to back that up.

The University of California’s Statewide Integrated Pest Management Program has a “page on horsehair worms” in which they explain that “if humans ingest the worms, they may encounter some mild discomfort of the intestinal tract, but infection never occurs.” That is to say, that horsehair worms only end up in humans through consumption of an already-infected host (an insect or crustacean), but they do not seek out humans as hosts.

Likewise, the National Center for Biotechnology Information has published an article titled “‘Two Human Cases Infected by the Horsehair Worm’“, in which they discuss “records of human accidental parasitism” of horsehair worms. They deem these cases “uncommon”. “As for the invasion route, the present human cases may have accidentally swallowed insects, such as a cricket or a beetle which is an intermediate host.”

One example of human ‘infection’ that the article discusses is the case of six people in Japan that accidentally ingested horsehair worms. Other than discomfort, they experienced no symptoms. Eventually, they expelled the worms through vomit or faecal matter. It is important to note that the vomiting and defecation were not symptoms caused by the horsehair worms burrowing in the gut of the humans as they would with an insect. Those that vomited had this reaction because the worms got stuck in their throat upon bursting out of the infected insect host. Those that excreted the worms did so because the worms only came out of the infected insect host after consumption, thus naturally ending up in the intestinal tract.

So yes, horsehair worms can end up in humans, but they do not gestate or mature in humans, nor do they burst out of humans. They do not migrate out of the digestive tract in humans, and, as the best medical knowledge at the time of writing this indicates, they do not produce any indirect symptoms, only the symptoms associated with something unpleasant in the digestive tract.

To conclude, this has been a brief, but necessary, clarification of the effects that horsehair worms can have on humans, and the extent to which they can really affect and infect us. We hope this clears things up for people, and we welcome any questions in the comments section below!


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Horsehair Worms in People (Nematomorpha Infestation in Humans) Inbox ALL ABOUT WORMS
Article Name
Horsehair Worms in People (Nematomorpha Infestation in Humans) Inbox ALL ABOUT WORMS
Horsehair worms are one of the most common parasites found in nature, and also one of the most misunderstood. Between the myths that surround them, as well as the vast claims that many make about them, this article intends to clear up any of the misinformation about horsehair worms, particularly their relationship to humans.

Share the knowledge

Author: Worm Researcher Anton

14 thoughts on “Horsehair Worms in People (Nematomorpha Infestation in Humans)

  1. Karma, yours is the closest to an exact description of symptoms I have come across. How are there so many suffering with this garbage and no info available. I’m so dejected anymore. I came close to ending my life twice. And I don’t take that lightly.

  2. Every comment of a symptom listed, I have experienced, plus more. I am a year into the acceleration of what I believe has been manifesting over the last ten years. Many people are experiencing the same exact rare disease and the medical industry is absolutely oblivious, or simply does not want to recognize or address something out of the ‘norm’ of their knowledge scope and/or capabilities. . I have been to several doctors and am now at one of the top medical clinics in the world and am seeing multiple specialists-they are stumped. I have an array of unexplained, but alarming bio markers that show a rapid digression in my overall health. I can not say for sure exactly what it is, but I am close. I believe it starts it’s lifecycle on/in the skin, travels through your blood or lymphatic system, then to other internal organs-not just GI. I believe it is Zootonic, undiscovered or extremely rare (accidental to humans) and will never be found in any normal lab or pathology testing. What I can tell is do not get discouraged, advocate for yourself. Start with lab tests (CBC + Metabolic Panel)- dive deeper into T and B cell and any liver related testing- they are affordable and you can easily order them yourself through a third party. Google: Ulta Labs + Tripment Health. If your tests are coming back without flags, then you are likely only a few years into this disease and can try to take steps on your own to help/reduce the symptoms and possibly reverse it all together. Start recognizing patterns, research, and document everything. Unless it is a lab result with your primary/specialty provider, do not discuss or show crazy pictures/videos with your social or medical circle. I’ve been there and it only will make you madder, get the crazy looks, and push you further into your own demise.

    I can tell you a few things to help you. 1. Epsom Salt/Himalayan: Get Dr. teals products-all of them: body wash, exfoliating salts, bath salts-take hot baths for 40 minutes, there is a fairly inexpensive epsom salt relief cream with lavender on Amazon-buy it and put it on everywhere multiple times a day. Buy organic coconut oil + food grade diatemaceous earth- mix it together and put it on your skin (I do this at night) + put a tablespoon into orange juice and drink it-daily. Find a local spa and go to the salt room and also check out the infrared saunas. Start mega-dosing on vitamin C (look for absorbic acid-liposomal). Start looking for high vitamin content SALT organic skin care products (Himalayan + Epsom). Buy Mud brand activated charcoal toothpaste and brush your teeth with it multiple times a day. Research organic foods (lemons) + supplements that help. I have found these remedies over time and by recognizing patterns. Because of the unfortunate recognition of this disease in every day medical care + family/friends, you will feel alone, self-isolate, have depression, and feel helpless. Once you recognize it is a part of the psychological side effects of this disease, then you can pull yourself out of the mental destitution and start taking steps to get better. Take this on as you are fighting it on your own. It will eventually start to show on lab tests and only then, will you have the ability to incorporate your healthcare providers. I promise you this… I am a fighter, explorer, am knowledgeable, and have the ability to handle the political oppression of what I believe to be substandard healthcare that we now receive. I promise that WHEN I get more definitive answers and diagnosis that I will post to n here again.

    1. Hi,
      I have these in my skin under my eye from a dog scratch. It has been two years. I am having good results with Ivermectin and Pyrantel which are both anti parasite drugs. I am in NYC, do you know of a doctor that can help?

  3. What kind of worm was in stool? Are you saying the test said worm in stool, but they didn’t identify what kind of worm? I was thinking about red-doing Dr ahmid test, but if they don’t identify worm it’s pretty much useless. Please answer. Thankvyou

  4. Is this possibly related to spiny water fleas or daphnia? I had positive test from PCI for nematode sp., d. Fragilis, candida, klebsiella. These are not those. They literally look like cat hair and sometimes I see random glitter near them. And they mate – they move. Youll eventually see one male and female together. So bizarre. One is wavy, one looks like a 7. The ones like a 7 have a white stripe. I have videotaped them moving on my clothing and counter. You can tease them and they will lunge at you. Out of ideas, I sprayed MMS CD solution on my skin and they jumped right out of my skin. They’re worms for sure. Very small. They size of cat hairs.

  5. Sum1 asked me if I emailed the corps of engineers bc my symptoms r just like all of yalls n I live in south Carolina where there always sumthing ready to eat the smaller thing around but this thing is being completely ignored. Nothing will go near it my poor doggies I may have to do the human thing for them. So please yall let’s become a thing n see wat w can do together bc the lord said any 2 gathered means it’s to become a bigger grouping n then a church…so I say let’s build a church. Lol I know so hard to laugh to n my relationship was perfect too but I’m loosing the fight.

  6. I also have the horsehair worm. This parasite is evil with only malice intent. I have found some treatments that work for short periods of time. I think there is a lot bigger population of human that have this parasite then anyone is aware off. People don’t want to seem nuts so they stay quiet. I can’t even go to the doctor anymore without talking to them with resentment. My mom is dying from this parasite. It’s awful. Anyone please co tact my is you would like to talk and trade pics and stories. This is a very lonely disease. Email me anytime – ch************@ya***.com

  7. I too have horse hair worms. I have been trying to get anyone in the medical community to listen to me with no success for well over a year now. They all think I am crazy, including my husband. I am not crazy. I have these darn things coming out of my nose, in my stool, in my mouth. They are everywhere and it is painful. The inside of my nose has round cysts where I believe they are laying their eggs. I even bought a microscope to prove to my husband they are alive and moving, but he won’t even look because he thinks I am crazy. I’m not crazy. I need help! No one will help me. I have been to so many doctors and they all treat me as if I have lost my mind. Of course, they have no explanation for all my intestinal issues, my nose bleeds, and a multitude of other issues. I just need someone to help me, please!

      1. Man dewayne, I’m sorry to hear that. But I can understand, the isolation, the solitude and the loneliness are all diff things but they all apply when you’re you’re hung thru this garbage hope you’re getting better man.

  8. I honestly thought I was going crazy everyone I told didn’t believe me they’d all look at me with a dormant look. I noticed a hard swelling in the top of my ear. No feeling or itch then the feeling of bugs crawling on me began. I started noticing what I thought were ingrown hairs then began feeling the ‘bites’ it’s like a sharp stinging burn. I’ve since started noticing ‘hairs’ getting tangled in my facal hair when I do manage to get one between my fingers to get a look they appear to be either white or brown/black thin hairs with tight waves while inspecting them they seem to have a mind of their own twisting, lifting and bending. When I inspect my skin I find small mite sized black specks and either a bright yellow or bright white speck. I went to my GP explaining everything and without a single examination he claimed formication. There is no way it is formication I have no explanation of what ‘it’ is but it’s really taking a toll on my mental health my family and my marriage. I shave hairs away and within no time I can find hairs that shouldn’t be as long as they are. Burning them leaves a much different look to normal hair. Insect repellent has lessened the feeling of them but it doesn’t take it away. I have emailed the CDC asking for some kind of guideline to work out what it may be.

  9. I can not find anything else similar to what i have…. HORSE HAIR WORMS!! Have ALL hair symptoms…. Bites me or can call it a sting, HARD, swell up like allergic. Tried all medicines repeatedly. 3rd time to ER 1st time said rash 2nd gave the “P” cream 3rd after a huge brown worm (size of the big fat earthworms, about 3 of them around) almost came out of my stomach white worms everywhere then the long hairs I thought spiders were going to erupt from my stomach but I got ambushed at triage and told to leave. My back is the worst I’d rather have quads, kidney stones over this. It goes to the core…my muscles…deep…i feel like there’s a 10s unit in my back, constant vibration. Now I’m glowing. I have black bugs come out of my skin. I have so many strange unbelievable pictures, its happening to me and i have to question my own sanity. its surreal. In my stool its like sticks, hard like off a tree, if I burn my hair its like a wooden looking vine. I’m terrified of my hair. Its crazy its like they are unified, threatenin. I’m a recluse I’ve always been a germaphobe, I don’t leave my house, my boyfriend goes to work where works mostly to himself. My back is so numb put blow dryer directly on it hoping heat would kill them, I couldn’t feel the heat or the burn. I don’t itch…. I’m in CONSTANT pain. Under microscope looks like blisters my chest turns green blue purple, I look jaundice under eyes yellowish green. Anyone know PLEASE PLEASE respond, seems like not many people have this, no info in CDC so I’d have to say no but i don’t know how that can be possible? My body is scared its just disgusting. At this point my ENTIRE body are covered with these things, hair that glows and moves, under microscope looks like its slimy, they glisten, I shaved yesterday comes back whatever length it wants. I’m really concerned under my skin you can see them growing EVERYWHERE. They have a distinct look, a hook they are every where. My bf and I got another prescription of ivermectin. It didn’t work before I have a worm in me on camera that is big, the infectious disease doctor says its impossible that big too blurry, in the film you see my belly button open, all of this is psychotic episodes?!. I still have this worm its like I’m pregnant, its so freaking disgusting, its impossible, yet here it is and no medicine is killing it. I feel like I’ve been in labor for 3 weeks now. How is this possible? I have to compartmentalize otherwise I’m afraid of the mental break I might have. I know this all sounds crazy, I know I sound crazy. But its all true I can’t deny it, I have to speak up. Something needs to change With the medical profession and if they don’t know they should admit that. i need a ER I need this out of me and I can’t go, its pathetic. Going to try the P cream again for a week. Wait for dermatology appt. My blood pressure is sky high I lost 20 lbs in month, I’m petite 5 ft 120-130 lbs., skinny. I feel like I’m doomed but if I let this worm come out and it helps 1 other person, then it was worth it. My bf don’t understand, this causes so many problems in a once perfect relationship. I just don’t know what to do. In 3 weeks did the Permethrin Cream approx. 10 times taken the 2x pills, steroids. Now these super super tiny glowing things pouring out of my nose, it looks like over a million. I have to keep my hair up in pins so no “hair” can touch me. I sometimes wonder am I in a coma and this new reality isn’t reality, I might wake up and be normal again.
    My biggest concern can my family get it, it was just Christmas is my grandkids infected? Little white glowing bugs were coming out of me that I didn’t notice til I got home. My hair will bite me and go back in me if it falls out could it hurt them? I’m terrified I want them to get checked but too afraid to tell my kids what’s wrong. This is NOT my hair its disgusting but they are worms!!

  10. I have exact things almost mirroring hers. I have 2 tests with positive dx for contaminated water and nematode in stool. From PCI arizona. I have bathed in this water 5 plus years. Only brushed my teeth in it. I cooked but boiled. Its well water. I do believe its accidental of course. But we’re have those dx gotten me. No where. I will give you any proof of mine you want. Mine was in larval stage so wasn’t I’d past nematode. I’m here if you wana talk you have my number from previous posts. And yes still have the same water even though I have called and emailed epa ,california state inspector, 800 hotlines nobody has even step foot or tried to take a look at this well water. The property management took a water sample was supposed to send me copy that was Sept 29th. Its crickets from. There end. If you have any other ideas I’m open to hearing them. I specifically spoke to Scott. And cannot get to dr amin. Unless I have a Dr that believes the tests but since they are sent outside usa they shut me down . So I suffer. With positive tests I followed from you guys. I’m just looking for help.

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