South Africa's malaria elimination teams could soon have backup from millions of decoy mosquitoes specially bred at Africa's first mosquito factory. These insects are part of South Africa's pioneering Sterile Insect Technique (SIT), developed through a joint partnership between the National Institute for Communicable Diseases (NICD) and Wits University.
NICD scientists have worked for a decade to rear and sterilize male swarms of Anopheles arabiensis to overwhelm the wild population. The idea is to supplement the country's existing Indoor Residual Spraying (IRS) efforts, which have helped shrink malaria spread by a home-dwelling mosquito called Anopheles funestus.
Progress toward complete malaria elimination has stalled, though, and Anopheles arabiensis may be the culprit. The insect can bypass IRS and insecticide-treated nets because it bites and rests outdoors.
The method that the NICD and Wits University have devised exploits the fact that wild Anopheles arabiensis females mate only once in their lifetime. If they mate with sterile decoys, the resulting eggs won't be viable, leading to population collapse.
To demonstrate that this high-tech package works in the real world, the program conducted a historic 12-week small-scale field trial in Mamfene, KwaZulu-Natal, the first release of an African malaria vector.
