Evidence for local transmission and maintenance of schistosomiasis in an urban neighbourhood in Northeast Brazil.

Schistosomiasis is a tropical neglected disease commonly associated with rural areas; however, urban schistosomiasis has been reported worldwide, and increasing urbanization is one of the most important demographic shifts of the 20th and now 21st centuries. The pattern of urbanization is not uniform so that within the same city the rates and sources of population increase vary. Here, we report on the parasite composition in one neighbourhood in the metropolitan area of Salvador, Bahia, Brazil. Using epidemiological data and population genetics, we find evidence for local transmission and maintenance of Schistosoma mansoni infection within an urban population and little contribution from rural-urban migration. Our findings provide direction for local mitigation strategies and to assist the public living in this neighbourhood to interrupt the local transmission cycle.