Trichuriasis is infection with the nematode (worm) Trichuris trichiura. Symptoms may include abdominal pain, diarrhea, and, in heavy infections, anemia and undernutrition. Diagnosis is by finding eggs in stool. Treatment is with mebendazole, albendazole, or ivermectin.
Trichuriasis is the third most common soil-transmitted roundworm infection. An estimated 800 million people are infected worldwide (1). Trichuris trichiura occurs more frequently in tropical areas with poor sanitation and among children. In the United States, most cases of trichuriasis are in immigrants or travelers returning from endemic areas, 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 intestine 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 approximately 1 year, although some may live longer.
(See also Approach to Parasitic Infections.)
General reference
1. Centers for Disease Control and Prevention: DPDx: Trichuriasis. Accessed October 21, 2024.
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 intestinal lumen.
Complete blood count (CBC) is done to check for anemia.
Treatment of Trichuriasis
Mebendazole
Albendazole
Ivermectin
Mebendazole is effective for patients with trichuriasis. Albendazole or ivermectin is also effective. A single 500-mg dose of mebendazole has been used in mass treatment programs, but single-dose regimens have low efficacy for trichuriasis (1). These medications should usually not be used during pregnancy.
If treatment with ivermectin is planned, patients should be assessed for coinfection withLoa loa if they have been in areas of central Africa where it is transmitted; ivermectin can induce severe reactions in patients with high levels of Loa loa microfilariae.
In one trial, a single dose of emodepside showed high efficacy against T. trichiura with cure rates of approximately 85% (2).
Treatment references
1. Moser W, Schindler C, Keiser J. Efficacy of recommended drugs against soil transmitted helminths: systematic review and network meta-analysis. BMJ. 2017;358:j4307. Published 2017 Sep 25. doi:10.1136/bmj.j4307
2. Mrimi EC, Welsche S, Ali SM, Hattendorf J, Keiser J. Emodepside for Trichuris trichiura and Hookworm Infection. N Engl J Med. 2023;388(20):1863-1875. doi:10.1056/NEJMoa2212825
Prevention of Trichuriasis
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 more frequently in tropical areas with poor sanitation and in children. Infections also occur in the southern United States.
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.
Treat with mebendazole, albendazole, or ivermectin.
If treatment with ivermectin is planned, assess patients for coinfection with Loa loa if they have been in areas of central Africa where it is transmitted because ivermectin can induce severe reactions in patients with high levels of Loa loa microfilariae.
