Trichinosis | |
---|---|
Other names | Trichinellosis, trichiniasis |
Trichinella larvae in pressed bear meat, partially digested with pepsin. The classic coil shape is visible. | |
Specialty | Infectious disease |
Symptoms | Initially: diarrhea, abdominal pain, vomiting[1] Later: swelling of the face, inflammation of the whites of the eyes, fever, muscle pains, rash[1] |
Complications | Inflammation of heart muscle, inflammation of the lungs[1] |
Causes | Trichinella from eating undercooked meat[1] |
Diagnostic method | Antibodies in the blood, larvae on tissue biopsy[1] |
Differential diagnosis | Measles, dermatomyositis, gastroenteritis[2] |
Prevention | Fully cooking meat[3] |
Medication | Albendazole, mebendazole[4] |
Prognosis | Low risk of death[5] |
Frequency | ~10,000 cases a year[6] |
Trichinosis, also known as trichinellosis, is a parasitic disease caused by roundworms of the Trichinella genus.[1] During the initial infection, invasion of the intestines can result in diarrhea, abdominal pain, and vomiting.[1] Migration of larvae to muscle, which occurs about a week after being infected, can cause swelling of the face, inflammation of the whites of the eyes, fever, muscle pains, and a rash.[1] Minor infection may be without symptoms.[1] Complications may include inflammation of heart muscle, central nervous system involvement, and inflammation of the lungs.[1]
Trichinosis is mainly spread when undercooked meat containing Trichinella cysts is eaten.[1] In North America this is most often bear, but infection can also occur from pork, boar, and dog meat.[7] Several species of Trichinella can cause disease, with T. spiralis being the most common.[1] After the infected meat has been eaten, the larvae are released from their cysts in the stomach.[1] They then invade the wall of the small intestine, where they develop into adult worms.[1] After one week, the females release new larvae that migrate to voluntarily controlled muscles, where they form cysts.[1] The diagnosis is usually based on symptoms and confirmed by finding specific antibodies in the blood, or larvae on tissue biopsy.[1]
The best way to prevent trichinosis is to fully cook meat.[3] A food thermometer can verify that the temperature inside the meat is high enough.[3] Infection is typically treated with antiparasitic medication such as albendazole or mebendazole.[4] Rapid treatment may kill adult worms and thereby stop further worsening of symptoms.[4] Both medications are considered safe, but have been associated with side effects such as bone marrow suppression.[4] Their use during pregnancy or in children under the age of 2 years is poorly studied, but appears to be safe.[4] Treatment with steroids is sometimes also required in severe cases.[4] Without treatment, symptoms typically resolve within three months.[5]
Worldwide, about 10,000 infections occur a year.[6] At least 55 countries including the United States, China, Argentina, and Russia have had recently documented cases.[5] While the disease occurs in the tropics, it is less common there.[5] Rates of trichinosis in the United States have decreased from about 400 cases per year in the 1940s to 20 or fewer per year in the 2000s.[6][8] The risk of death from infection is low.[5]
During 2008–2010, 20 cases were reported to CDC each year on average.
During 2002–2007, 11 cases were reported to CDC each year on average.