The discovery of a new subgroup of malaria-carrying mosquito may explain why malaria eradication efforts have had limited success.

Malaria is caused by Plasmodium parasites (pictured, in red), which are transmitted by mosquitoes, mainly of the species Anopheles gambiae. Kenneth Vernick at the Pasteur Institute in Paris and his colleagues discovered the new subgroup of A. gambiae — dubbed Goundry for the village in the African country of Burkina Faso, where it was found — after collecting mosquito larvae from puddles, raising them to adulthood in the lab and genetically analysing them.

Not only do the Goundry mosquitoes live primarily outdoors, where they avoid indoor insecticide sprays, they also acquire the parasite more easily than their indoor relatives. When fed with malaria-infected blood, 58% of Goundry mosquitoes picked up the disease, compared with just 35% of indoor mosquitoes.

Credit: K. VERNICK

Science 331, 596–598 (2011)