The behavioural effect of tobacco smoke on endophilic
Anopheles mosquitoes was observed in two
North Central Nigerian villages. Pyrethrum spray and exit trap collections of mosquitoes were conducted, between April
and November 2014, in two different villages where tobacco smoking was common among the residents.
Anopheles
mosquito samples collected were identified to sibling species level using species-specific polymerase chain reaction.
Presence of human blood in the blood-fed mosquitoes was determined by Enzyme-linked immunosorbent assay. Numbers
of mosquitoes collected from the rooms inhabited by tobacco smokers and non-smokers were compared using Student’s
t-test (
p<0.05). At least four times higher exit rates, five times less gravid females and significantly lower numbers of
An. gambiae
s.l mosquitoes were found in rooms inhabited by tobacco smokers compared to equal sized rooms occupied by
non-smokers in each village. Blood feeding rates (77-88%) and human blood indices (0.82-0.87) of mosquitoes were
generally high in the habitations of both tobacco smokers and non-smokers. There was predominance of
An. gambiae (≥
86%) species compared to
An. coluzzii (≤ 14%) in both villages. Reduced mosquito endophily was observed in the
habitations of tobacco smokers compared to the non-smokers. Widespread tobacco smoking habits should be investigated
for possible contributions to mosquito behavioural resistance and residual malaria parasite transmission within rural
communities.
