Given A New Type Of Insecticide, Mosquito Nets Can Reduce Malaria Cases In Tanzania

Illustration of a mosquito net. (Unsplash/Jane Stroebel)

JAKARTA - Mosquito nets treated with a new type of insecticide have almost halved cases of malaria in children in a large Tanzanian trial, according to a study in the journal 'The Lancet', raising hopes for a new weapon in the fight against the old killer.

Bed nets have been instrumental in the great progress the world has made in recent decades against malaria, with millions of lives saved.

However, progress has stalled in recent years, in part because the mosquitoes that spread the infection are becoming increasingly resistant to the insecticides used in existing mosquito nets.

In 2020, 627,000 people died from malaria, mainly children in sub-Saharan Africa, Reuters reported March 25.

Now, researchers at the London School of Hygiene and Tropical Medicine in the UK (LSHTM), the National Institute for Medical Research with Kilimanjaro Christian University College of Medicine in Tanzania, and the University of Ottawa in Canada, have shown that a new insecticide, the first in 40 years, is safe. and effective in real-world randomized trials.

The nets, treated with chlorfenapyr as well as pyrethroids, a commonly used chemical, reduced malaria prevalence when compared with existing bed nets by 43 percent in the first year and 37 percent in the second year of the trial.

This study involved more than 39,000 households and followed more than 4,500 children aged 6 months to 14 years. The nets, developed by BASF in Germany and LSHTM, are slightly more expensive than current nets, at around $3 per item. However, the researchers said the savings in preventing cases outweighed the initial increase in spending.

Chlorfenapyr works differently than pyrethroids, effectively 'dropping' mosquitoes by causing wing cramps and rendering them unable to fly, and therefore bite, spreading infection.

This chemical was first proposed for use against malaria 20 years ago, and has been used for pest control since the 1990s.

The World Health Organization (WHO) has pre-qualified the use of the new nets, but the trial, funded by the UK government and the Wellcome Trust, could lead to broader recommendations for its use.

"This is the first evidence under real-life conditions," Dr Jacklin Mosha, lead author of the study from the National Institute for Medical Research, Tanzania, told Reuters.

Along with progress on a malaria vaccine, which was approved by the World Health Organization last year, the team says the net could be another tool in the malaria toolbox.

However, they warn, it is important to ensure that mosquitoes also do not quickly develop resistance to chlorfenapyr, if used widely.