Schistosomiasis is caused by adult parasitic flatworms (Schistosoma) which develop from skin-penetrating larvae released by freshwater snails. The adult female shistosoma live in the blood vessels and release eggs which can be passed out in excreta, often cialis 20mg contaminating freshwater sources, or stay in the body and damage organs and blood vessels. Access to clean water and sanitation is one of the most important factors in controlling and eliminating this disease.

According to WHO, at least 261 million people required preventative treatment for schistosomiasis in 2013.