A new weapon in the battle against malaria has taken to the skies.
On Tanzania's Zanzibar archipelago, researchers are flying drones armed with Aquatain AMF, a non-toxic colorless solution.
It's being sprayed on rice fields - typical breeding grounds for the anopheles mosquito that spreads malaria.
The liquid creates a thin film on top of the water, preventing mosquito pupae and larvae from breathing at the surface.
Put simply, it drowns them.
It's a method that tackles the transmission of malaria at the source, says Dr Bart Knols.
(SOUNDBITE) (English) MOSQUITO BIOLOGIST, DR. BART KNOLS, SAYING:
"This is where the problem starts. These are the breeding grounds of mosquitos, so once we control them here we will see far fewer mosquitos making it to the houses where people live, biting these people and therefore transmitting malarial disease."
The World Health Organization says malaria killed 435,000 of the 219 million people who were infected in 2017; Sub Saharan Africa accounted for more than 90 percent of global deaths.
Scientists hope to expand this technology across the continent, saying the drones are efficient and cost-effective.
That's especially when dealing with large irrigated areas, saying Professor Wolfgang Richard Mukabana.
(SOUNDBITE) (English) UNIVERSITY OF NAIROBI MALARIA SCIENTIST, PROFESSOR WOLFGANG RICHARD MUKABANA, SAYING:
"As you can see the way the paddies look like, it is very difficult to just walk through the paddies and apply the chemicals so you want to have something that can just spray it on the water surface, it spreads, does the job and that's it."
The Aquatain solution is made by Australian company Aquatain Products, which says it is highly permeable to gases - meaning that while it stops the mosquitos from breathing, it still allows the water to be oxygenated.