Development of a modified baited trap for detection of schistosome cercariae using natural oils rich in polyunsaturated fatty acids in Sudan

Cercariometric methods for monitoring the presence of schistosome cercariae in natural water systems have been unable to provide realistic data in a feasible manner. Apart from the task of filtering or centrifuging large volumes of water, the presence of suspended matter, plankton and debris has made visualisation and identification of the target organisms difficult. We have adapted a cercarial trap which utilised unsaturated fatty acids in a matrix of clear nail varnish, modified it by using locally available natural oils as stimulant and soft wax as the matrix and tested it under laboratory and field conditions in Sudan. The new system has potential for use in identifying important transmission foci.