Laboratory of Tropical Diseases, National Institutes of Health, Institute of Tropical Medicine, Bowman Gray School of Medicine, School of Public Health, University of North Carolina, Bethesda 14, Maryland
A study was made of the endemic area of schistosomiasis mansoni at Hato Mayor in the Dominican Republic. Australorbis glabratus, the snail host for Schistosoma mansoni, seems to have a very restricted distribution in the vicinity of Hato Mayor. Numerous A. glabratus were found in streams close to the town but none was found in other streams up to 20 kilometers from the town. Many of the snails harbored cercariae which developed into adult S. mansoni in mice. Examination of a single stool from each of 243 children between the ages of 5 and 15 living in Hato Mayor revealed 52 infections with S. mansoni.
It is concluded that a serious endemic focus of schistosomiasis mansoni exists in the vicinity of Hato Mayor, and that the disease is being acquired by a relatively large proportion of the children of the town. Because the endemic area is apparently restricted to narrow geographic limits, it is considered especially well suited for a study on the use of molluscacides in the control of schistosomiasis mansoni.