Trichina worm
The Trichina worm, a type of roundworm belonging to the genus Trichinella, is known for causing a disease called trichinosis. This disease typically occurs when humans or animals consume undercooked meat that contains the worm's eggs, which can hatch and develop into adult worms within the host. Trichina worms are found in a wide variety of carnivorous mammals, including domestic animals like pigs and wild species such as bears and raccoons. The life cycle starts when an animal ingests cysts containing the eggs, leading to severe health issues, particularly for humans, who can experience symptoms ranging from gastrointestinal distress to severe muscle pain and complications like pneumonia if not treated. Although trichinosis is less common in modern meat markets, it still affects millions globally each year. Cooking meat thoroughly is crucial to preventing infection, as it kills the cysts present in the meat. Awareness of the risks associated with consuming undercooked pork is essential for food safety and health.
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Trichina worm
Trichina worms are the cause of a common disease known as trichinosis. Many animals get trichinosis when they prey on other animals that contain these worms and their eggs. Humans may get trichinosis when they eat pork in which the worm's eggs are present and the meat has not been thoroughly cooked.
Kingdom: Animalia
Phylum: Nematoda
Class: Enoplea
Order: Trichocephalida
Family: Trichinellidae
Genus: Trichinella
Species: Various (see below)
The trichina worm is a species of roundworm known to cause a disease called trichinosis. Trichinosis occurs when people or animals eat meat containing the worm’s eggs. The eggs grow into worms inside their bodies and cause trichinosis.
The trichina worm is found worldwide in many animals. It may occur in dogs, cats, martens, ferrets, skunks, minks, bears, badgers, raccoons, foxes, coyotes, wolves, pumas, opossums, oxen, sheep, goats, horses, rabbits, guinea pigs, beavers, porcupines, moles, walruses, rats, and pigs. It likely occurs in almost any carnivorous, or meat-eating, mammal.
Trichinosis also infects people. The disease is less likely to be found in meat markets than in the wild, and fewer people in modern countries get trichinosis, but it is still common and strikes millions of people each year.
The life cycle of the trichina worm begins when the trichina egg cysts get inside an animal, for example, a pig. This may happen when the pig eats meat or uncooked garbage containing the eggs. Sometimes the worm is called the garbage worm. The hard, shell-like cysts around the eggs dissolve in the pig, and the worm larvae, or young, hatch. The larvae enter the small intestine and are adults in two to six days. About two days later, a male and female mate, the male dies, and the female burrows into parts of the body, where she lays eggs. She may lay 1,000 to 1,500 eggs within six weeks before she dies. The young from these eggs travel in the bloodstream through the heart and lungs and burrow into the muscles of the pig within three months of hatching. Within another three to six months, they form hard, shell-like cysts around themselves. They can live inside these cysts for up to 11 years.
When the pig is slaughtered, the trichina cysts are in the meat and muscles. People buy the pork to eat. Unless they cook the pork thoroughly before eating it, the cysts will dissolve inside the people's bodies, and the process begins again. Thorough cooking of the pork kills any cysts that may be in the meat.
The trichina worm causes greater trouble in people than in the pig. The first stages of trichinosis bring diarrhea, nausea, vomiting, abdominal pains, weakness, muscle twitches and pains, and swelling in the face and eyelids. In the second stage, after 9 to 10 days, the worms enter the people's muscles and cause severe muscle pain, difficulty in breathing, chewing, and swallowing, and redness in the eyes. After this stage comes painful swelling in the arms, legs, abdomen, and face, along with pneumonia, anemia, and fevers caused by the worms forming cysts in the person’s muscles. If the disease is severe and untreated, people can die four to six weeks after eating the infected meat.
An adult male trichina worm is 1/20 to 1/10 of an inch (1 1/2 to 3 1/5 millimeters). This worm has the same general body features as other roundworms. They can remain alive inside a host for months or years.
Species include:
Trichinella britovi
Trichinella nativa
Trichinella nelsoni
Trichinella papuae
Trichinella pseudospiralis
Trichinella spiralis
Bibliography
Freed, Daniel and Peter DiGennaro. "Pork Worm." Entomology And Nematology Department, University of Florida, Apr. 2022, entnemdept.ufl.edu/Creatures/NEMATODE/Trichinella‗spiralis.htm. Accessed 15 May 2024.
Hartwell, Ginger. "Trichinella Spiralis." Animal Diversity Web, animaldiversity.org/accounts/Trichinella‗spiralis. Accessed 15 May 2024.
"Trichinosis." Mayo Clinic, 25 May 2022, www.mayoclinic.org/diseases-conditions/trichinosis/symptoms-causes/syc-20378583. Accessed 15 May 2024.