The hide and seek game between malaria and man is continuing with man getting the better of the pathogen or sometimes, the enemy gaining upper hand. Interbreeding between two mosquito species has created a super species which is resistant to nets treated with malaria insecticide.
According to a research which was published in the Journal Proceedings of the National Academy of Sciences a new species has been discovered in the West African country of Mali as a result of an evolutionary change caused by the introduction of treated nets to the environment.
The insecticide treated mosquito nets have played an important role in reducing the number of malaria deaths which has decreased by 47% since 2000.However the specialists are not surprised by the mosquitoes developing resistance.
Lead researcher and medical entomologist Gregory Lanzaro in a release said, “Growing resistance has been observed for some time. Recently it has reached a level at some localities in Africa where it is resulting in the failure of the nets to provide meaningful control, and it is my opinion that this will increase.”
The newly discovered super mosquito has obtained the ability to survive the insecticides used to treat bed nets. The development of the super mosquito will once again put into question the effectiveness of these insecticide treated bed nets.
Gregory adds, “Its ‘super’ with respect to its ability to survive exposure to the insecticides on treated bed nets. It provides convincing evidence indicating that a man-made change in the environment – the introduction of insecticides – has altered the evolutionary relationship between two species, in this case a breakdown in the reproductive isolation that separates them. What we provide in this new paper is an example of one unusual mechanism that has promoted the rapid evolution of insecticide resistance in one of the major malaria mosquito species.”
Anopheles gambiae is a major vector of malaria and it is interbreeding with isolated pockets of another malaria mosquito, A coluzzii. They are now being recognized as a separate species and they have developed resistance against treated bed nets.
There is an urgent need to develop new and better malaria vector control strategies. These include new insecticides, biological agents like mosquito killing bacteria and fungi, genetic alteration of the mosquitoes to negate their ability to transmit the plasmodium protozoa.
However, it was just a matter of time for insecticide resistance to emerge, experts say.
Now there is “an urgent need to develop new and effective malaria vector control strategies,” Lanzaro said.
The study was published in the journal PNAS.