A child lying under a mosquito net, Kenya, East AfricaCredit: Mile 91/Ben Langdon/Alamy Stock Photo
Insecticide-treated mosquito nets have been the main preventive measures against malaria in the past decade in sub-Saharan Africa, with hundreds of millions of malaria cases averted attributed to them. However, the development of resistance to pyrethoids, the insecticide incorporated into bed nets fibres, in malaria vectors is threatening their usefulness.
A new study published in The Lancet reveals a novel class of bed nets treated with two different insecticides is more effective to control mosquitoes that have developed resistance to traditional bed nets, significantly reducing malaria in children.
Unlike standard insecticides which kill mosquitoes on contact through the nervous system, the chlorfenapyr insecticide causes mosquitoes to die by rendering them unable to move or fly, and therefore unable to fend for themselves.
Led by Jacklin Mosha from the National Institute for Medical Research in Mwanza Tanzania, the researchers surveyed over 4,500 children aged six months to 14 years from more than 39,000 households in Misungwi district, Mwanza region in Tanzania, where high levels of resistance to standard pyrethoids insecticides have been reported.
“These children were randomized into four groups and three groups received one of three of the most promising new generation of bed nets and another group received the standard mosquito nets. The children were then tested for malaria at the end of each rainy season," explained Mosha.
“After 24 months, malaria infection dropped by 37% in children that received the new chlorfenapyr insecticide net compared to those receiving standard pyrethroid nets,” she added.
