Targeting mosquito breeding sites could help control malaria spread

A malaria control method that targets mosquito larvae and pupae as they mature in standing water, could be instrumental in the fight against the disease.

The Cochrane review-led by the London School of Hygiene and Tropical Medicine in collaboration with Durham University and other researchers in the UK and US-is the first systematic review looking at using larval source management (LSM) to control malaria, which causes an estimated 660,000 deaths worldwide every year.

It found evidence that the method may significantly reduce both the number of cases of malaria by up to 75 percent, and the proportion of people infected with the malaria parasite by up to 90 percent when used in appropriate settings.

LSM is a method that targets immature mosquitoes, found in standing water, before the females develop into flying adults that are capable of transmitting malaria.

This is done by permanently removing standing water, for example by draining or filling land; making temporary changes to mosquito habitats to disrupt breeding, for example by clearing drains to make the water flow; or larviciding by adding chemicals or biological larvicides to standing water to kill larvae.

Currently the use of long-lasting insecticide treated bed nets and indoor residual spraying of homes are widely used for malaria transmission control and are having a major impact on the burden of the disease.

However, this success is now threatened by factors such as a growing resistance to insecticides among mosquitoes.

Complementary methods of mosquito control such as LSM may become increasingly necessary in helping tackle the disease, and some malaria-endemic countries in Sub-Saharan Africa are already implementing LSM programmes, but there is a lack of consensus on how effective the method can be and in which settings it is appropriate.