New Outdoor Mosquito with Malaria Parasite Found in Kenya

Researchers have discovered a new species of mosquito in Africa that could pose a major threat to the battle against malaria.

A team of researchers found the new mosquito species in the Kisii village in the highlands of western Kenya that do not resemble any other mosquito species in Africa, but has the potential to infect and cause malaria.

Unlike female anopheles, which causes malaria, by feeding on humans at night, the new mosquito species stayed outdoors and bit humans before night (10.30 p.m.).

For their study, the research team set up traps in the Kisii village, an area where there is unstable transmission of malaria, to catch the mosquitoes. They trapped 348 mosquitoes of which more than 65 percent were caught outdoors before night. When they performed a DNA analysis, they found that 40 percent of the mosquitoes were unidentified species as their DNA sequences differed from the normal mosquitoes.

Experts also noticed that five of the mosquitoes were carrying parasites that could spread malaria.

"We observed that many mosquitoes we caught, including those infected with malaria, did not physically resemble other known malaria mosquitoes. Analysis indicated that their DNA differed from sequences available for known malaria-transmitting mosquitoes in Africa," Lead author Jennifer Stevenson, research fellow at the London School of Hygiene & Tropical Medicine (LSHTM), said in a news release.

"These unidentified mosquitoes are potentially dangerous because they are outdoor-active and early-biting, and so may evade the current indoor-based interventions to control mosquitoes. In this way, they may prevent the complete suppression of malaria transmission in the area," she said.

While indoor mosquitoes that attack during the night are being tackled using various tools such as bed  nets or spraying insecticides, the new outdoor mosquito species is posing a big threat to the Kenyans as malaria is the leading cause of death in the country.

According to a report from Kenya Medical Research Institute (KEMRI), a national organization that carries out health research in Kenya, 25 million out of a population of 34 million Kenyans are facing a risk of malaria.

Experts called for better understanding and focus to deal with the transmission of malaria through outdoor mosquitoes. They insisted on monitoring mosquitoes in order to develop better malaria control programs.

"The practical implication for malaria control program is that there is no substitute for careful monitoring of mosquito populations.  In order to be effective, such monitoring must be carried out by specialist experts who have the skills to recognize and investigate unexpected entomological observations," Jo Lines, reader in malaria control and vector biology at LSHTM, said in the news release.

The findings of the study are published in Emerging Infectious Diseases.