Impact of human schistosomiasis in sub-Saharan Africa

Human schistosomiasis otherwise called bilharzia, is a fresh- water snail transmitted intravascular debilitating disease resulting from infection by the parasitic dimorphic Schistosoma trematode worms, which lives in the bloodstream of humans. The World Health Organization (WHO) regards the disease as a neglected tropical disease, with an estimated 732 million persons being vulnerable to infection worldwide in renowned transmission areas. Steinmann and co-workers documented that over 200 million individuals from Africa, Asia, and South America are infected with this disease. The WHO further estimated that schistosome infections and geohelminths accounts for over 40% of the world tropical disease burden with the exclusion of malaria. Humans get infected with this disease when they make contact with water contaminated with the skin-penetrating cercariae. Prevalence of schistosomiasis, at present, is still high in sub-Saharan Africa. In 2008, 17.5 million people were treated globally for schistosomiasis, 11.7 million of those from sub-Saharan Africa only. Approximately 120 million individuals in sub-Saharan Africa have schistosomiasis-related symptoms while about 20 million undergo hardship as a result of chronic presentations of the disease.