Stories tagged parasites
A tapeworm: like a friend that will always be with you. A friend that's taller than you are. Living in your intestines.
Courtesy SavadorjoI just came across this tasty little item on CNN.com: A Chicago man recently passed a nine-foot-long tapeworm, which he believes to have gotten from undercooked salmon.
I’m not sure of the best way to express my feelings on this subject, so let’s just talk about tapeworms.
Tapeworms are, of course, parasitic flatworms. Humans can become infected with tapeworms by consuming food or water contaminated with the eggs or larvae of the worm. You might not think it, but whether one is infested with eggs or larva can make a big difference. If you accidentally eat the eggs, the larvae that hatch from them may migrate out of your intestines, and make little cystic homes in other parts of your body, like your lungs or liver. These cysts are both super gross, and super dangerous—you can die from them, and treatment is difficult. If, on the other hand, you unwittingly eat tapeworm larvae, it’s much more likely that the baby worm will snuggle up in your guts, and eat what you eat. This is super gross, and still pretty bad for you, and it’s best if you avoid it.
If you do get a tapeworm living in your intestines, as the man in the story did, you may suffer from nausea, diarrhea, abdominal pain, weakness, and loss of weight. Or you might not demonstrate any symptoms at all. But you’ll still have a huge worm living inside you.
There are a variety of tapeworm types that might infect you, including the beef tapeworm, the pork tapeworm, the dwarf tapeworm, and the fish tapeworm. Some tapeworms go through their whole lifecycle inside one host, developing from egg to larva to adult, while others attach themselves to the lining of the intestine, and others still allow themselves to be passed (into the toilet).
According to the Mayo clinic’s page on tapeworms, adult worms can grow up to fifty feet inside their hosts. So, all things considered, the Chicago guy should feel lucky.
Tapeworm eggs can be passed from one person to another via… stool… so be sure to wash your hands. Constantly.
Tags : Next year, researchers plan to start small-scale human trials of a malaria vaccine that's proven 75-80% successful in mice.
It's probably not the worst day in this caterpillar's life: But it's the worst day it will remember.
Courtesy The Agricultural Research ServiceThat’s a lie, really—If I suddenly discovered that I had the ability to lay eggs inside a living caterpillar, I would probably have myself sealed in a basement. An eternity of being bricked off in an alcove is probably preferable to an all-encompassing desire to stab an ovipositor into moth larvae.
Unless you’re a wasp. It seems that the world, in its unceasing attempts to gross us out, has come up with something new: a wasp that lays eggs in a caterpillar. That, obviously, is nothing remarkable—all sorts of things stick their offspring in other things. This wasp, however, turns the caterpillar into a zombie guardian of the wasp larvae as they hatch and crawl out of its body. Oh, man! What a trick!
So, the wasp larvae hatch (again, inside the body of the caterpillar), and then chew their way out of its body. Once they’re out, and doing…whatever it is parasitic wasp larvae do (Sega Genesis?), the caterpillar stops eating, remains close to the larvae, and uses its head as a club, thrashing its body to beat away any predators.
I’m sure that all the other little wasplings are super jealous of those who have huge zombie bodyguards, but, more than that, research has shown that zombie caterpillar bodyguards increase chances of larvae survival by 200%.
So, to refine my earlier statement, if I could turn caterpillars into zombie servants, I would. But not if it meant that I had to lay little JGordon eggs in them. Yuck. I don’t think that’s how I was born (although my mother has always been pretty vague on the subject, and my father always refused to discuss it at all).
A harmless bot fly: kind of cute, really.
Courtesy Wikimedia CommonsHave you thrown up yet today?
Oh, you haven’t? That’s fine if you haven’t. Not even an issue, really.
Forget that. Let’s go and learn about science!
Have y’all heard of the bot fly? They’re a little gray fly, native to the Americas, and they’ve got the most fascinating life-cycle.
Just a second—it feels like there’s a tiny person with diarrhea camping out in my stomach. Sorry, that was totally unrelated.
Anyway, the bot fly has a remarkable life cycle, especially the bot fly species dermatobia hominis. Pupating in the soil, the adult d. hominis emerges after about a week, and sets out looking for a mate and a mosquito. Once the bot fly finds and catches a mosquito, surprisingly, it doesn’t hurt the captured insect at all. The fly just attaches its own eggs to the mosquito’s body.
Now, I know what you’re thinking—you’re thinking that this is going to be one of those bugs that lays its eggs in another insect and leaves it alive so that when the eggs hatch the new larva can eat the living host. Get that thought out of your head right now; it’s simply not the case.
Oh, man, I feel like I’m salivating a lot. And burping.
Anyway, now we have this mosquito giving bot fly eggs a friendly lift. The mosquito goes about its life, looking for a blood meal. When the mosquito finds a mammal to drink from (usually a monkey or a person in the case of d. hominis), the eggs hatch, and the itty-bitty bot fly larva drop off the mosquito on to its host. The larvas then crawl into the tiny hole conveniently provided by the mosquito, and make a little home for themselves. For the next eight weeks, they feed off the tissue under the skin of their host until they grow into a large grub, about three quarters of an inch long, ringed with strong, hooked barbs, which make extracting the larva quite difficult and painful. Once the eight weeks are up, they chew their way out of the skin, and drop to the ground, where they burrow into the dirt. And about a week later…an adult fly is born once again! Isn’t nature a miracle?
Wait! Don’t leave yet! I have something else for you: a video I like to call The miracle of (bot fly) birth. I can’t make you watch it, but you probably should.
Now I think I have to go lie down and take some deep breaths
Hookworms in the lining of the intestines: All together now: "ewwwwwwwwwwww."
Courtesy Centers for Disease Control and Prevention
Cleanliness is next to godliness, but is it possible to have too much of a good thing? For several decades, immunological diseases -- such as hay fever, asthma, diabetes and multiple sclerosis – have been increasing in developed countries, but are uncommon in many undeveloped regions. Medical researcher Joel Weinstock theorizes that modern life is too clean – by scrupulously avoiding dirt, bugs and germs, our immune systems don’t develop properly, leading to the diseases listed above. Weinstock goes so far as to speculate that exposure to hookworm, pinworm, and other intestinal parasites may have been the trigger necessary for developing a healthy immune system. As these parasites have been eradicated, immunological diseases have skyrocketed.
The theory is currently being tested in the lab. Weinstock doesn’t advocate the return of worm infestations. But he does think that getting your hands dirty once in a while can help keep your body in balance.
An alternate theory holds that dinosaurs died of embarrassment: A Fredrogersaurus, obviously wishing he were dead, extinct, or just anywhere but here.
Courtesy Elston
Biting insects spread all kinds of diseases. (You can learn all about this in the Science Museum’s newest exhibit, Disease Detectives.) Now a scientists thinks they may have also helped kill off the dinosaurs. George Poinar, a professor of zoology at Oregon State University, notes that many insects from dinosaur times have been preserved in amber. Many of them carry microbes that can cause malaria, dysentery and other illnesses. He speculates that these illnesses could have been the major cause of the dinosaurs’ long, slow demise. The asteroid impact / volcanic activity / climate change simply finished them off.
Poinar and his wife Roberta have published a book, What Bugged The Dinosaurs? Insects, Disease And Death In The Cretaceous. In it they also note that, late in the dinosaur era, flowering plants spread rapidly, helped along by newly-evolved insect pollinators. This sudden change in available food may have also played a hand in the dinos’ extinction.
As I watched the praying mantis crawling on my hand, I noticed something brownish coming out of its bottom. At first I thought it was feces, but then it started wriggling around vigorously. Was it a tapeworm, or some unknown species of worm?
We brought the worm home in a bag and searched on the internet. It was a hairworm, a parasite that feeds on the insides of insects and brainwashes the insects into jumping into the water, where it completes its lifecycle. That makes sense because the praying mantis jumped off my hand into a wading pool just before I brought it onto land and the hairworm started coming out.
We've only found examples of hairworms coming out of grasshoppers and rarely emerging from damselfies/dragonflies. Has a hairworm ever before been observed coming out of a praying mantis? I found it on Oct. 4, 2006 at Kyodo no Mori in Fuchu-shi in Tokyo when my 4th grade class from ASIJ was on a field trip.
My name is Elsa and I am nine years old. I want to be either an entemologist or a herpetologist when I grow up.
It seems like science fiction, or some bizarre insect zombie movie, but...
Hairworm: A hairworm swims away from its drowned grasshopper host. Image by VB Films
Scientists have been researching the parasitic relationship between grasshoppers and the nematomorph hairworm (Spinochordodes tellinii). The hairworm lives and breeds in fresh water, but spends a part of its life eating the insides of live grasshoppers and then brainwashing the grasshopper into committing suicide by hopping into a pool of water and drowning. The hairworms, several times the length of the grasshopper at the time of the unfortunate incident, then emerge and continue their lifecycle in water. A team of researchers at the French National Center for Scientific Research is studying just how the hairworm manages to take over the body of the grasshopper.
This is just one example of a parasite seemingly taking over its host to produce specific results. In Costa Rica, there is a wasp whose larva lives inside the body of an orb-weaving spider. The evening before the larva kills the spider, the larva somehow manages to reprogram the web building activity of the spider so that it creates a durable platform for the larva to pupate on, instead of its usual temporary web. Studies show that if the larva is removed from the spider before the larva kills the spider, the spider will return to its usual web building activities within a couple of days.
And, if you think about it, the rabies virus makes animals so rabid that they want to bite others — which transmits the virus.
Creepy, huh?
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