Are hookworms in humans deadly skin#
Are hookworms in humans deadly full#
Are hookworms in humans deadly free#

I wrote my medical school application essay about schistosomes, and about using scientific knowledge to interrupt cycles which led to human disease. I was fascinated by the worms, but I began to understand better how much suffering they could cause, and to resent the ways in which they exploited poverty and disadvantage, and made health disparities more extreme.

And as I studied with experts in the fields of medicine and public health, I found myself drawn toward their perspective, becoming interested not only in how these life cycles evolved but also in the question of how they could be interrupted. I went off to graduate school to study the evolutionary biology of parasitic worms. They can complicate the steps that children take to school, or the ways that adults fetch water or grow crops or catch fish for dinner. They can get into the animals we eat and can hitch rides on the insects that like to suck our blood, which is to say, they can get into the animals which like to feed on us. They can get into the water that we wade in or the ground on which we walk. So look at all the ways that worm life-cycles have evolved to take advantage of human habits and human behavior. And the tapeworms take a different route into our bodies tapeworm larvae infect an intermediate host, a pig or a cow, and we get the infection by eating insufficiently cooked meat. These are hermaphroditic segmented flatworms, with each segment a complete reproductive system, so that each segment can become stuffed with eggs. Other roundworms - such as the microfilaria, which cause elephantiasis and river blindness - are transmitted to humans by biting flies which inject the larval worms into our blood vessels.ДЄnd then there are the cestodes, or tapeworms - again, a different biology, a different worm anatomy. The hookworms are nematodes, or roundworms, a completely different phylum of invertebrates with a very different worm anatomy, and a completely different life cycle - their eggs hatch in warm moist soil, and the larvae burrow up through bare human feet.

Are hookworms in humans deadly full#

If the world is full of worms, the parasitic worms who make their homes in humans are a staggeringly diverse group, ranging from those schistosomes, who are trematodes or flukes, flatworms without body cavities to the hookworms, which live in our GI tracts, where they hook on and suck blood. An estimated 240 million people worldwide are infected with schistosomiasis. As a life cycle it is almost impossibly baroque, with specialized larvae navigating from mammals to molluscs to mammals, and adults pairing off in the blood vessels - and yet the parasites are extremely widespread.

Are hookworms in humans deadly skin#

Inside the snails, they go through a couple of larval stages, then emerge as cercaria, tadpole-shaped larvae that can penetrate human skin and find their way to the blood vessels and there they mature to that adult stage, where they live in copula and produce the eggs that continue the cycle. The eggs are excreted out with either feces or urine, If they get to water, they hatch into swmming larvae, called miracidia, which seek out snails, their intermediate hosts.

And eventually, the infection can be fatal. The worms cause schistosomiasis, also known as вЂњsnail fever,вЂќ whose symptoms can include anemia, abdominal pain and kidney and liver damage. I wrote my biology senior thesis in college about the life cycle of the schistosomes, the blood flukes that make their home in human blood vessels, where, as adult flatworms, they live permanently coupled ( in copula said my textbook, poetically), producing eggs.

Are hookworms in humans deadly free#

I was stunned by their ornate life cycles, and the complex biology required to get from host to host, and to live successfully inside those hosts, without being wiped out by the hostsвЂ™ immune system and without wiping the hosts out and ending the free ride (not to mention the free lunch).

I was studying evolutionary biology, and I got caught up in the idea of organisms that made their world out of other organisms. As a college undergraduate, I fell in love with parasitic worms.