trichuriasis /trik′yərī″əsis/ [Gk, thrix + oura, tail, osis, condition] , infestation with the roundworm Trichuris trichiura. The condition is usually asymptomatic, but heavy infestation may cause nausea, abdominal pain, diarrhea, and, occasionally, anemia and rectal prolapse. It is common in tropical areas with poor sanitation. Eggs are passed in feces. Contamination of the hands, food, and water results in ingestion of the eggs, which hatch in the intestines where the adult worms embed two thirds of their length in the intestinal mucosa. The worms may live 15 to 20 years. Treatment is with mebendazole; prevention includes proper disposal of feces and good personal hygiene. Also called trichiuriasis.