Occurrence of snail intermediate host of schistosomiasis: implication for schistosomiasis control based on mass drug administration of praziquantel in Benue State, Nigeria

Abstract

Schistosomiasis is a neglected disease that is still ravaging many rural community dwellers in Nigeria. Different species of freshwater snails, such as Bulinus and Biomphalaria, play passive roles in the transmission of schistosomiasis. A study on the occurrence of snail intermediate hosts of schistosomes were conducted following mass praziquantel administration in Katsina-Ala, Benue State, Nigeria. The objective was to determine prevalence of freshwater snails incriminated in transmitting schistosomiasis and their cercaria infectivity. A total of 24,812 freshwater snails belonging to six different genera (Bulinus globosus, B. forskalii, Pila ovata, Lanistes lybicus, Biomphaleria pfeifferi and Lymnae natalensis were encountered. Snails collected were kept under laboratory condition for cercaria emergence. B. globosus, B. forskalii and B. pfeifferi were identified as vectors of Schistosomes because there secreted cercaria of S. haematoium and S. mansoni respectively. Parasite infection was higher in the ponds (83.33 %); followed by dams (68.57 %)) and streams (53.33 %). There was positive correlation (r = 0.657; P < 0.05) between the amount of rainfall and abundance of all snail species and their infection rate collected except Biomphalaria species that showed negative correlation. The studies therefore, call for Consideration of snails control to be integrated with Praziquantel Mass Drug Advocacy Campaigns so as to achieve transmission interruption.