Mass Drug Administration of Triclabendazole for Fasciola Hepatica in Bolivia

Human infection with Fasciola hepatica leads to obstruction of the common bile duct by adult worms and disease characterized by biliary colic, epigastric pain, and nausea. Recommended treatment is a single dose of triclabendazole (TCBZ) (10 mg/kg). Because in the 1990s the Bolivian Altiplano bordering Lake Titicaca was thought to have the highest prevalence of human fascioliasis worldwide, the Bolivian Ministry of Health instituted TCBZ mass drug administration (MDA). From 2008 to 2016 (excepting 2015), one dose of 250 mg was administered, usually in September/October, to each resident of highly endemic regions willing to participate. This is apparently the first reported use of MDA for Fasciola. The proportion of persons in key regions receiving TCBZ MDA was 87% in 2016. In 2017, we resurveyed key regions, and found that the MDA program had been dramatically successful. Whereas Fasciola prevalence was reported as 26.9% in Huacullani/Tiahuanaco and 12.6% in Batallas in 1999, there was 0.7% prevalence in Huacullani/Tiahuanaco and 1% in Batallas in 2017. However, lessons from schistosomiasis control efforts suggest that for sustained control of Fasciola infection, Fasciola MDA needs to be maintained and coupled with measures to control infection in the intermediary snail and in the animal hosts of F. hepatica.