If you blamed mosquitoes alone for spreading malaria, think again. It turns out mosquitoes are mere victims while the "villain" is the malaria parasite.
Malaria parasites alter the chemical odour signal of their hosts to attract mosquitoes and better spread their offspring, reveals new research.
This scent change could be used as a diagnostic tool, researchers said.
"Malaria-infected mice are more attractive to mosquitoes than uninfected mice," said Mark Mescher, associate professor of entomology at Pennsylvania State University in the US.
"They are the most attractive to these mosquito vectors when the disease is most transmissible," said Mescher.
Malaria in humans and animals is caused by parasites and can be spread only by an insect vector, a mosquito.
The researchers found that using a mouse malaria model, the mosquitoes were more attracted to infected mice even when the mice were otherwise asymptomatic.
"Mosquitoes would not opt to carry the malaria parasite because it is not good for the mosquito," said Consuelo De Moraes, professor of entomology at Pennsylvania State University.
"Probably the parasite is not only manipulating the mice to alter their scent, but the mosquitoes to be more attracted to the infected scent," De Moraes added.
In regions where malaria is prevalent, significant numbers of people harbour asymptomatic infections but remain able to transmit the disease to others.
"We were most interested in individuals that are infected with the malaria parasite but are asymptomatic," said De Moraes.
"Asymptomatic people can still transmit the disease unless they are treated, so if we can identify them we may be able to better control the disease," De Moraes explained.
The researchers hope this altered scent profile might help to identify those needing treatment.
The findings were published in the journal Proceedings of the National Academy of Sciences.
