The effect of controlled release copper sulphate and tributyltin fluoride on the mortality and infectivity of Schistosoma mansoni cercariae

Abstract

Mortality and infectivity or Schistosoma mansoni cercariae were tested against various concentrations of controlled release copper sulphate (EC-8) and tributyltin fluoride (CBL-9B). The results indicate that survival of cercariae varied with concentrations of molluscicide and times of exposures. Statistical analysis reveals that LC50and LC90for EC-8 were 1.18 mg/l/hour and 1.82 mg/l/hour while LC50and LC90forCBL-9B were 16.8/ug/l/hour and 21.7/ug/l/hour respectively. Sublethal concentration of both molluscicides reduced cercarial infectivity considerably. The doses of 0.25 to 0.5mg/l/hour for EC-8 and 2.0 to 6.0/ug/l/hour for CBL-9B were found to be sufficient to inhabit cercarial penetration of the host skin. © 1982, Cambridge University Press. All rights reserved.