Despite new information that the disease burden of schistosomiasis in Africa may be equivalent to malaria or HIV/AIDS and a simple annual anthelminthic treatment for this disease is available for less than 50 cents per person including delivery costs, we now know that fewer than 5% of the infected population is receiving coverage. To date, this situation represents one of the first great failures of the “global health decade” that began in 2000. The scaling up of praziquantel manufacture and distribution, together with operational research and new product research and development, would represent a global assault on schistosomiasis.
The neglected tropical diseases (NTDs) are the most common conditions affecting the poorest 500 million people living in sub-Saharan Africa (SSA), and together produce a burden of disease that may be equivalent to up to one-half of SSA’s malaria disease burden and more than double that caused by tuberculosis. Approximately 85% of the NTD disease burden results from helminth infections. Hookworm infection occurs in almost half of SSA’s poorest people, including 40–50 million school-aged children and 7 million pregnant women in whom it is a leading cause of anemia. Schistosomiasis is the second most prevalent NTD after hookworm (192 million cases), accounting for 93% of the world’s number of cases and possibly associated with increased horizontal transmission of HIV/AIDS. Lymphatic filariasis (46–51 million cases) and onchocerciasis (37 million cases) are also widespread in SSA, each disease representing a significant cause of disability and reduction in the region’s agricultural productivity. There is a dearth of information on Africa’s non-helminth NTDs. The protozoan infections, human African trypanosomiasis and visceral leishmaniasis, affect almost 100,000 people, primarily in areas of conflict in SSA where they cause high mortality, and where trachoma is the most prevalent bacterial NTD (30 million cases). However, there are little or no data on some very important protozoan infections, e.g., amebiasis and toxoplasmosis; bacterial infections, e.g., typhoid fever and non-typhoidal salmonellosis, the tick-borne bacterial zoonoses, and non-tuberculosis mycobaterial infections; and arboviral infections. Thus, the overall burden of Africa’s NTDs may be severely underestimated. A full assessment is an important step for disease control priorities, particularly in Nigeria and the Democratic Republic of Congo, where the greatest number of NTDs may occur.
By preventing urogenital schistosomiasis in sexually active females through simple and low-cost methods, we have an innovative and timely opportunity to reduce and possibly interrupt HIV/AIDS transmission throughout many rural areas of sub-Saharan Africa.
More than 90% of the world’s 207 million cases of schistosomiasis occur in sub-Saharan Africa, making this condition (as well as hookworm infection) one of the most common neglected tropical diseases in the region. Based on additional information that schistosomiasis causes chronic anemia and inflammation associated with severe disability among children, adolescents, and young adults, the disease burden resulting from schistosome infections in Africa may actually rival better known conditions such as HIV/AIDS, tuberculosis, and malaria.