Schistosomiasis, also known as Bilharzia or 'snail fever', is a water-borne parasitic worm disease transmitted by freshwater snails. Schistosomiasis can be found worldwide, especially in rural (sub) tropic areas without access to water and with poor sanitation. It ranks second only to malaria as the most common parasitic disease infecting 240 million people in 78 countries with 90% of the burden occurs in Africa. Moreover, it is the most deadly NTD, killing more than 200,000 people each year in Africa. There are two forms of the disease, intestinal and urogenital schistosomiasis, with several overlapping symptoms, including rash in the first two days and fever, chills, coughs and muscle pain within the first two months. When left untreated, schistosomiasis can persist for years and progress into a chronic disease. Abdominal pain, diarrhoea, enlarged liver and blood in stools are common in chronic intestinal schistosomiasis infections. In chronic urogenital infections, women may present blood in urine, genital lesions, vaginal bleeding and nodules in the vagina, while men may present pathology in the seminal vesicles, prostate and other organs. In advanced stages and left untreated, the disease can progress into irreversible kidney damage, bladder cancer and infertility. Complications regarding the urogenital organs may result in feeling embarrassed and not having the courage to visit a doctor, subsequently leading to progression of the disease and social stigma.
Towards control and elimination
The control of schistosomiasis is based on annual large-scale treatment of at-risk population groups, especially school-aged children, and interrupting transmission through improved access to safe water, improved sanitation, hygiene education and snail control. Estimates show that at least 258 million people required preventive treatment for schistosomiasis in 2014. More than 61.6 million people were reported to have been treated for schistosomiasis in 2014.