More than 200 million people in Africa suffer from the worm disease schistosomiasis with more than 200,000 dying every year from its consequences. This chronic and parasitic disease is thus the second most common tropical disease in Africa after malaria.

Schistosomiasis is particularly widespread in the tropical and subtropical areas of sub-Saharan Africa. In these regions, a vast majority of the population has no access to clean water and sanitary installations. The disease is transmitted by flatworms and is spread in freshwater. People become infected by worm larvae while, for example, swimming, fishing, playing or washing their clothes.

Since 2007, Merck has been supporting the World Health Organization (WHO) in the fight against schistosomiasis in Africa.