New Insecticide Formulation Re-Energizes Fight Against Malaria

Oct 2014
AIRS entomological studies funded by PMI find new insecticide formulation lasts up to nine months.
AIRS entomology technicians in Ghana attach WHO cone bioassays to a sprayed wall to test the decay rate of the insecticide Actellic 300 CS.

Indoor Residual Spraying (IRS) is one of the most effective ways to prevent malaria. Sprayed on the inside walls and ceilings of homes, the right insecticide can reduce the density and life span of vector mosquitoes so that they can no longer transmit malaria parasites. For IRS to be effective, however, the malaria-carrying mosquito must be susceptible to the sprayed insecticide. Currently, only a limited number of insecticides are effective as mosquitoes are becoming increasingly resistant to the common insecticides used in IRS, threatening malaria prevention programs.

The PMI-funded Africa Indoor Residual Spraying (AIRS) Project conducts entomological surveillance to test mosquito resistance to, and the residual life of, insecticides throughout the malaria transmission period. Based on entomological monitoring data in Ghana, AIRS found that the new insecticide formulation, Actellic 300 CS, is proving to be highly effective. Data shows the insecticide is lasting up to nine months in some areas, covering even the longest malaria transmission seasons.

Working with Ghana’s National Malaria Control Program, entomological surveys were conducted in 13 communities in four districts in Ghana between March 2013 and March 2014. AIRS used the standard WHO cone bioassay method on a monthly basis to assess the decay rate of the insecticide when sprayed on each type of structure (cement, mud, wood).

Although Actellic 300 CS is more expensive than other insecticides currently used for IRS, its long-lasting efficacy is eliminating the need to conduct a second round of spray operations in areas where the transmission period can last up to nine months.

Based on AIRS entomological data, more PMI-funded countries are adopting the use of Actellic 300 CS. Benin, Mali, Madagascar, Senegal, Zambia and Zimbabwe have all switched to using Actellic 300 CS for IRS.

This story was taken from

Annual Report

13th Annual Report to Congress
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