Mosquito larval source management for controlling malaria

Mosquito larval source management for controlling malaria

Lucy S Tusting1, Julie Thwing2,*, David Sinclair3, Ulrike Fillinger1, John Gimnig4, Kimberly E Bonner5, Christian Bottomley6, Steven W Lindsay1,7

London School of Hygiene and Tropical Medicine, Department of Disease Control, London, UK
US Centers for Disease Control and Prevention (CDC), Strategic and Applied Science Unit, Malaria Branch, Atlanta, Georgia, USA
Liverpool School of Tropical Medicine, Department of Clinical Sciences, Liverpool, UK
US Centers for Disease Control and Prevention (CDC), Entomology Branch, Atlanta, Georgia, USA
Princeton University, Woodrow Wilson School of Public and International Affairs, Princeton, New Jersey, USA
London School of Hygiene and Tropical Medicine, MRC Tropical Epidemiology Group, London, UK
Durham University, School of Biological and Biomedical Sciences, Durham, UK

Tusting LS, Thwing J, Sinclair D, Fillinger U, Gimnig J, Bonner KE, Bottomley C, Lindsay SW. Mosquito larval source management for controlling malaria. Cochrane Database of Systematic Reviews 2013, Issue 8. Art. No.: CD008923.

To read the full review please follow this link: DOI: 10.1002/14651858.CD008923.pub2. 

What is larval source management and how might it work?

Malaria is an infectious disease transmitted from person to person by mosquitoes, and the main interventions insecticide treated bed-nets and indoor residual spraying reduce malaria infection by targeting adult mosquitoes. Larval source management (LSM) also aims to reduce malaria but instead targets immature mosquitoes, which are found in standing water, before they develop into flying adults. 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 by adding chemicals, biological larvicides, or natural predators to standing water to kill larvae.

What does the research show?

We examined all the published and unpublished research up to 24 October 2012, and included 13 studies in this review.

Where larval habitats are not too extensive and a sufficient proportion of these habitats can be targeted, LSM probably reduces the number of people that will develop malaria (moderate quality evidence), and probably reduces the proportion of the population infected with the malaria parasite at any one time (moderate quality evidence).

LSM was shown to be effective in Sri Lanka, India, the Philippines, Greece, Kenya, and Tanzania, where interventions included adding larvicide to abandoned mine pits, streams, irrigation ditches and rice paddies where mosquitos breed, and building dams, flushing streams, and removing water containers from around people’s homes.

In one study from The Gambia where mosquitos were breeding in large swamps and rice paddies, spraying swamps with larvicide using ground teams did not show any benefit.