New mosquito highly susceptible to malaria parasites, harder to kill

The discovery of a previously unknown type of mosquito in Africa that's highly susceptible to malaria parasites and, disturbingly, whose habits thwart current malaria control efforts, has researchers worried about the future.

The researchers spent four years collecting mosquitoes from ponds near villages in Burkina Faso. They found a subtype of Anopheles gambiae mosquitoes unlike any that have turned up in collections before.

Their research is published in this week's edition of the journal Science.

Unlike most mosquitoes that research has focused on, these blood-suckers live outdoors instead of hanging around inside where the humans, and their nice supply of blood, live.

Most malaria transmission from mosquito to human happens inside, but these new mosquitoes have an edge in that malaria control efforts are also concentrated indoors.

They note that a control project in Nigeria during the 1970s failed because genetically distinct outdoor-resting mosquitoes allowed malaria transmission to persist despite indoor insecticides.

This unique A. gambiae subtype is significantly more susceptible to the Plasmodium falciparum parasite that causes malaria. The researchers don't yet know if it takes blood meals from humans, nor how large its home range is.

From its genetics, the researchers think this particular subgroup may be evolutionarily quite young. Much more research into its habits and the problems it causes needs to be done, they say.