Changes in schistosome cercarial densities at different periods and depths of a field water pool in Jos, Nigeria

Abstract

A field ditch which contains water all year round and harbors Biomphalaria pfeifferi, the intermediate host of Schistosoma mansoni was investigated for five months (September, 1994 - January, 1995) for cercarial densities at different periods of the day and depths at Farin-Gada area of Jos, Nigeria. Results revealed the following distribution of brevifurcate cercariae: Surface (2 - 3 cm depth) 69%; subsurface (7 - 8 cm depth) 10.2% and bottom (³ 15 cm) 25.9%. Cercariae preferred the surface area of the water at any given time of the day. The implications of this distribution and the fact that the ditch serves as a ready source of water supply for the inhabitants within the vicinity in the dry season are discussed.

JOURNAL OF AQUATIC SCIENCES Volume 16, Number 2, October 2001, pp. 119-123




KEY WORDS:

Cercariae, Biomphalaria pfeifferi, Schistosoma mansoni, Jos, Nigeria