Trichinella spiralis
- Primary cause of trichinellosis, also called trichinosis.
– Be aware that other species of
Trichinella can also cause trichinellosis.
Humans and other meat-eating animals are exposed to Trichinella* when they eat the undercooked flesh of infected animals.
– Because pigs are omnivores,
pork products are a significant source of trichinellosis in humans.
- In the human gastrointestinal tract, adult worms reproduce.
The larvae exit the GI tract and migrate to striated muscles, including cardiac and skeletal muscle tissue*.
- In the skeletal muscles, the larvae encyst and can calcify
– Some species of
Trichinella do not encyst, but can nevertheless remain viable for several years.
- Symptoms of trichinellosis vary, and depend on worm load and location.
– Early infection, if symptomatic, is characterized by
abdominal pain and gastrointestinal symptoms.
– The
muscle stage develops approximately a week later, and is characterized by
muscle pain and swelling caused by worm migration in the tissues and the inflammatory response.
– Skeletal muscle throughout the body can be infected, including the tongue and diaphragm. Pain, swelling, and weakness can be severe enough to limit movement and breathing.
– Other indicators of trichinellosis include
periorbital and facial swellings, retinal and conjunctival hemorrhaging, and subungual splinter hemorrhages (during the diagnostic stage, look for small dark red vertical lines under the nails).
– More serious infections can involve the
heart, lungs, and brain.
Image Credits:
Bruschi, F. "New Aspects of Human Trichinellosis: The Impact of New Trichinella Species." Postgraduate Medical Journal 78, no. 915 (January 1, 2002): 15–22. https://doi.org/10.1136/pmj.78.915.15.
"Trichinella Spiralis." Wikipedia, November 12, 2018. https://en.wikipedia.org/w/index.php?title=Trichinella_spiralis&oldid=868404656.
