Mosquitoes infected with the malarial parasite Plasmodium
falciparum are significantly more attracted to human odours than uninfected
mosquitoes, according to research published in the open access journal PLOS ONE by James Logan and colleagues
from the London School of Hygiene & Tropical Medicine, UK.
The authors investigated the response of mosquitoes infected
with P. falciparum malaria parasites and uninfected to human odour collected on
a fabric matrix. Mosquitoes that were infected with the parasites landed and
probed significantly more than uninfected mosquitoes in response to the odour.
Previous research has already shown that the malarial parasite can alter
mosquito behaviour in ways that increase the rate of malaria transmission.
For example, malaria-infected mosquitoes also consume
larger, more frequent blood meals than their uninfected counterparts. For the
first time this study reports that, "malaria-infectious females are more
attracted to human odours than uninfected mosquitoes".
According to the researchers, studies of mosquito behaviour
in the context of malaria transmission usually use uninfected mosquito
subjects, and their study suggests that such behavioural studies may not always
be representative of the behaviour of infected mosquitoes. They conclude that
understanding the olfactory changes underlying the behaviour of these infected
mosquitoes may help identify new compounds that could be used to develop
mosquito traps for surveillance programmes.