New fungus-based pesticides zap out mozzies

Jun 12 2005

Researchers at Imperial College London, have discovered that mosquitoes carrying a malaria parasite, when exposed to surfaces coated with fungus-based pesticides had a dramatically reduced ability to transmit malaria.

Senior author Dr. Matt B. Thomas says that fungal pesticide sprays might possibly be a replacement for, or a supplement to, chemical insecticides for malaria control, particularly in areas of high insecticide resistance.

In their study the researchers assessed the effect that various fungal pesticides had on reducing mosquito-borne transmission of Plasmodium chabaudi, a malaria parasite that affects rodents.

They found that exposure to surfaces treated with the fungal pesticides reduced the number of mosquitoes that were able to transmit malaria by a factor of about 80.

Also with exposure periods comparable to what is likely to occur in natural settings, greater than 90 percent mosquito mortality rates were achieved.

Dr. Bart G. J. Knols, from Wageningen University in the Netherlands, and colleagues in a related study,showed that a control strategy using fungal insect pathogens could be implemented in Africa, at the rural village level, and would significantly reduce malaria transmission rates.