Discovery of what attracts pregnant mosquitoes is used to fight malaria

The battle against malaria is also a battle against its natural host, the mosquito, which means disrupting the insect's lifecycle is every bit as important as putting nets over beds. Now, an international research team has discovered what attracts mosquitoes to lay their eggs in specific places.

 

 

 

 

Some of the traps being tested with a substance that attracts female mosquitos looking for nesting spots to lay their eggs.

Credit: OviART

 

 

"We have been able to show that it is no coincidence where mosquitoes lay their eggs," says Jenny Lindh, a researcher from KTH Royal Institute of Technology. "They use both vision and their sense of smell."

With this finding, the research group OviART is designing mosquito traps that could help cut down the population of the genus, Anopheles, which is the primary vector of malaria.

Experimenting with different soil and water mixtures, the research team concluded that a constituent of earth found in breeding sites near Kenya's Lake Victoria -- a substance called cedrol -- is particularly attractive to the malarial mosquito, precisely at the time when the female is ready to ovulate.

"This is the first time we have been able to prove that Anopheles react to a particular substance when they are looking for nesting," Lindh says. "This is a big step, to prove that it is possible to lure the mosquito to a specific spot with an attractant."

That knowledge is being used to test traps in Kenya that can compete with mosquitoes' preferred spots, natural puddles big and small. The mosquito traps employ fans to spread the fragrance and to suck the mosquitoes in, Lindh says.

But before declaring victory, the researchers must make sure their traps work in environments with different kinds of conditions. "We have identified a substance that mosquitoes are attracted to but it's highly probably that they also react to other substances," she says. "The more we know the more effective we will be in limiting the number of malaria cases."

Source: KTH The Royal Institute of Technology.

Journal Reference:

1. Jenny M Lindh, Michael N Okal, Manuela Herrera-Varela, Anna-Karin Borg-Karlson, Baldwyn Torto, Steven W Lindsay, Ulrike Fillinger. Discovery of an oviposition attractant for gravid malaria vectors of the Anopheles gambiae species complex. Malaria Journal, 2015; 14 (1) DOI: 10.1186/s12936-015-0636-0