Trichuriasis is infection with Trichuris trichiura
(See also Approach to Parasitic Infections.)
Trichuriasis is the 3rd most common soil-transmitted roundworm infection. An estimated 604 to 795 million people are infected worldwide. Trichuris trichiura occurs principally in developing tropical or subtropical areas where human feces is used as fertilizer or where people defecate onto soil. Children are the most heavily infected. In the United States, most cases of trichuriasis are in immigrants or travelers returning from endemic areas with poor sanitation and hygiene, but there are locally acquired cases in some southern areas.
Infection is spread via the fecal-oral route. Ingested eggs hatch and enter the crypts of the small bowel as larvae. After maturing for 1 to 3 months, the worms migrate to the cecum and ascending colon, where they attach to the superficial epithelium, mate, and lay eggs.
Image from the Centers for Disease Control and Prevention, Global Health, Division of Parasitic Diseases and Malaria.
Adult worms are estimated to live 1 to 2 years, although some may live longer.
Symptoms and Signs of Trichuriasis
Light Trichuris infections are often asymptomatic.
Patients with heavy infections may have abdominal pain, anorexia, and diarrhea; weight loss, anemia, and rectal prolapse may result, particularly in children.
Diagnosis of Trichuriasis
Microscopic examination of stool
Diagnosis of trichuriasis is made by microscopic examination of stool; the characteristic lemon-shaped eggs with clear opercula at both ends are readily apparent. When anoscopy, proctoscopy, or colonoscopy is done for other indications, wiggling adult worms may be seen protruding into the bowel lumen.
Complete blood count (CBC) is done to check for anemia.
Treatment of Trichuriasis
Loa loaLoa loa microfilariae.
Prevention of trichuriasis is possible through effective sewage disposal systems, sanitary food preparation, avoidance of potentially contaminated water, and good personal hygiene including handwashing.
Key Points
Trichuriasis occurs principally in developing tropical or subtropical areas where human feces is used as fertilizer or where people defecate onto soil, but infections also occur in the southern United States, mainly in children.
Infection is spread via the fecal-oral route.
Light infections are often asymptomatic; heavy infections may cause abdominal pain, anorexia, diarrhea, and, in children, weight loss, anemia, and rectal prolapse.
To diagnose trichuriasis, examine a stool sample for the characteristic lemon-shaped eggs with clear opercula at both ends.
Loa loaLoa loa microfilariae.
