Epidemiology, burden and control of schistosomiasis with particular consideration to past and current treatment trends

Schistosomiasis, or bilharzia, is a chronic and debilitating disease caused by blood flukes of the genus Schistosoma. The most important species parasitizing humans are S. haematobium, S. japonicum and S. mansoni. While the former causes genitourinary tract lesions, the latter two affect the intestine and the liver. It is estimated that 779 million people are at risk of schistosomiasis, with 207 million people infected. Here, we summarize the epidemiology of schistosomiasis, including the life cycle, key epidemiological features and the disease burden. We discuss the shift in the global control strategy from transmission containment to morbidity control, which has been facilitated by the advent of safe and effective antischistosomal drugs, most notably praziquantel. We provide an overview of the history of schistosomiasis control, stratified by major subregions of the world where the disease is endemic, and update the current global picture of control. We review early treatment attempts and present the current arsenal of drugs, i.e., oxamniquine, praziquantel and the artemisinins. We present recent data obtained in laboratory studies and clinical trials with triclabendazole and myrrh. Current treatment trends with praziquantel are summarized and a series of conclusions is forwarded.