The head of the malaria division at Rwanda Biomedical Centre told the BBC that the drones would be loaded with 10 litres of an insecticide that kills mosquitoes at their larval stage.

"The unmanned aerial vehicles are going to support the existing efforts that include mosquito nets and housing sprays to fight anopheles which spread malaria," Aimable Mbituyumuremyi said

"Now we also want to fight these mosquitoes from their sources. The drones will spray a sort of larvicide, which kills that type of mosquitoes," he added.

About 3.9 million people were diagnosed with malaria between 2018 and 2019, according to the Rwanda Biomedical Centre.

The mass spraying of mosquitoes is targeting specific areas with the highest cases and is said to be safe for humans.

"The drugs which will be sprayed over the marshlands and swamps are verified to be harmless to the people, farms and environment. These substances are produced from bacilli bacteria which are normal in the environment and approved by the World Health Organisation," Dr Mbituyumuremyi said.

He says the efforts will further reduce infections.

Malaria cases dropped from 4.8 million in 2017 and the number of deaths dropped from 660 in 2016 to 260 in 2019, according to the centre.

Rwanda has also been using drones to supply blood to 21 remote clinics.