Investigating the public health impact of the spread of pyrethroid resistance in malaria vectors

It is estimated that 68% of the 663 million cases of malaria that have been prevented since the year 2000 are attributable to the use of long-lasting insecticide treated bednets. In recent years, there has been a worrying increase in mosquito resistance to pyrethroid insecticides; the only insecticide currently available for use on bednets. It is currently unknown whether the extended geographic range and magnitude of resistance is due to the mass distribution of bednets or whether it has evolved due to other selection pressures, such as insecticide use in agriculture. The public health impact of resistance is also unclear, though it is feared its spread puts malaria control in jeopardy as all newly-developed bednets likely to be used in the next decade will contain pyrethroids.
Using historical records of the spread of pyrethroid resistant mosquitoes and epidemiological data on malaria prevalence, the relationship between malaria prevalence, bednet use and the level of insecticide resistance will be statistically examined. This data will then be further analysed through the use of mathematical models of disease transmission dynamics to investigate whether the observed increase in the spread of insecticide resistant mosquitoes can explain temporal trends in malaria and the effectiveness of mosquito control programmes.