trichinella spiralis


Trichinosis is a parasitic disease caused by eating raw or undercooked pork or wild game infected with the larvae of a species of roundworm Trichinella spiralis, commonly called the trichina worm.

The great majority of trichinosis infections have either minor or no symptoms and no complications. A large burden of adult worms in the intestines promote symptoms such as nausea, heartburn, dyspepsia, and diarrhea from two to seven days after infection, while small worm burdens generally are asymptomatic. As the larvae migrate through tissue and vessels, the body’s inflammatory response results in edema, muscle pain, fever, and weakness. A classic sign of trichinosis is periorbital edema, swelling around the eyes, which may be caused by vasculitis. Splinter hemorrhage in the nails is also a common symptom.

The most dangerous case is worms entering the central nervous system. They cannot survive there, but they may cause enough damage to produce serious neurological deficits (such as ataxia or respiratory paralysis), and even death.

If you would like to read about a very odd case of trichinosis as well as other fascinating parasitic cases, I highly recommend this book, The Woman with the Worm in Her Head by Doctor Pamela Nagami. It is beautifully but plainly written, so you do not need to be in med school to enjoy it.


Adventures in Parasitology

Strongyloides stercoralis

S. stercoralis is a nematode parasite that will enter the body through the skin of the feet or legs (symptom known as “ground itch”). It inhabits the GI and pulmonary tracts; one of the most common symptoms of an infection with this parasite is persistent diarrhea. 

Trichinella spiralis

This is one of my favorite nematodes. You can become infected with Trichinella by eating raw or undercooked pork meat. The larvae of this parasite will migrate to the striated muscle tissue and form what are called “nurse cells”, encysting themselves in the tissue. 

Oh my goodness. There are suddenly quite a lot of you. That happened rather suddenly, welcome! Feel free to ask me questions if you like, parasites are one of my favorite topics of discussion, so chatting about it I enjoy! 

I apologize for the lull. For now, thank you for following, here are some pictures of parasites I have taken myself and am proud of.

From top to bottom that’s: Schistosoma mansoni, a male and female mated pair, a nurse cell larva complex holding Trichinella spiralis, and a hatching Hymenolepis diminuta egg that looks like Pacman! (I grew that little bugger myself, feed a beetle feces, fed a rat the beetle guts, and dissected it to produce this little beauty.)