A child sleeps under a mosquito net.In a recent study, nets treated with clofenapyr reduced malaria prevalence by 43% in the first year and 37% in the second year compared to standard pyrethroid-only nets.Photos | Documents
A new type of bed net that can neutralize mosquitoes resistant to traditional insecticides has significantly reduced malaria infections in Tanzania, scientists say.
Compared to standard pyrethroid-only nets, the nets significantly reduced malaria prevalence, cut childhood infection rates by nearly half and reduced clinical episodes of the disease by 44 percent over the two years of its trial.
Unlike the insecticides that kill mosquitoes, the new nets make mosquitoes unable to fend for themselves, move or bite, starving them to death, according to research published in March in The Lancet.
In this study involving more than 39,000 households and more than 4,500 children in Tanzania, it was found that long-lasting insecticidal nets treated with two insecticides, chlorfenapyr and chlorfenapyr LLIN, reduced Malaria prevalence was reduced by 43% compared to standard pyrethroid-only nets, and a second reduction of 37%.
The study found that clofenapyr also reduced the number of malaria-infected mosquitoes caught by 85 percent.
According to scientists, clofenapyr acts differently than pyrethroids by causing spasms in the pterygoid muscles, which prevent the function of the flight muscles.This prevents the mosquitoes from coming into contact with or biting their hosts, which can eventually lead to their death.
Dr. Manisha Kulkarni, associate professor at the University of Ottawa’s School of Epidemiology, said: “Our work adding clofenac to standard pyrethroid nets has great potential to control malaria transmitted by drug-resistant mosquitoes in Africa by essentially ‘grounding’ the mosquitoes. “Public Health.
In contrast, bed nets treated with piperonyl butoxide (PBO) to enhance the efficacy of pyrethroids reduced malaria infections by 27% within the first 12 months of the trial, but after two years with the use of standard nets.
The third net treated with pyrethroid and pyriproxyfen (neutered female mosquitoes) had little additional effect compared to standard pyrethroid nets.The reason is not entirely clear, but it may be due to insufficient pyriproxyfen remaining online over time.
“Although more expensive, the higher cost of clofenazim LLIN is offset by savings from reducing the number of malaria cases requiring treatment. Therefore, households and societies distributing clofenazim nets are more likely to be The overall cost is expected to be low,” said the team of scientists, who hope the World Health Organization and malaria control programs will adopt the new nets in areas with insecticide-resistant mosquitoes.
Findings from the National Institute of Medicine, Kilimanjaro Christian University College of Medicine, London School of Hygiene and Tropical Medicine (LSHTM) and the University of Ottawa are welcome news on a continent where standard bed nets fall short of protecting people from parasites .
Insecticide-treated bed nets helped prevent 68% of malaria cases in sub-Saharan Africa between 2000 and 2015.Over the past few years, however, the decline in malaria rates has stalled or even reversed in some countries.
627,000 people died of malaria in 2020, compared to 409,000 in 2019, mostly in Africa and children.
“These exciting results show that we have another effective tool to help control malaria,” said the study’s lead author, Dr Jacklin Mosha from the Tanzania National Institute of Medical Research.
The “non-flying, non-biting mosquito grounded net,” marketed as “Interceptor® G2,” could lead to significant malaria control gains in sub-Saharan Africa, the team said.
However, they say more research is needed to test the feasibility of scaling up and to suggest the resistance management strategies needed to maintain efficacy in the long term.
“Caution is required,” warns co-author Natacha Protopopoff.”The massive expansion of the standard pyrethroid LLIN 10 to 20 years ago led to the rapid spread of pyrethroid resistance. The challenge now is to maintain the effectiveness of clofenazepam by developing rational resistance management strategies.”
This is the first of several trials with clofenapyr mosquito nets.The others are in Benin, Ghana, Burkina Faso and Côte d’Ivoire.
Arid and semi-arid regions were the worst hit, with the country’s crop production down 70 percent.