Making Mosquitoes Deaf Can Stop Spread Of Dengue, Study Finds

Scientists may have found a unique way to fight mosquito-borne diseases such as dengue, yellow fever and Zika -- by turning the male mosquitoes deaf so they cannot mate and breed. Both male and female mosquitoes produce sounds as they beat their wings at distinct frequencies during flight. The Aedes males are attracted to this wingbeat and use it to mate mid-flight. Researchers at the University of California conducted an experiment where they altered the genetic pathway that males use for hearing.

The results showed them making no physical contact with the female, even after being left in the same cage for three days, which was in stark contrast to their usual mating habits. On average, male mosquitoes complete copulation and insemination within 20 seconds of contacting a female, and almost always in less than a minute.

The scientists targeted a protein called trpVa which is believed to be important for hearing. The results revealed that the neurons in the experimented mosquitoes which help detect sound, showed no response to the flight tones or wingbeats of females.

"The trpVa1/2 mutant males showed no sound attraction regardless of the frequency, demonstrating that TRPVa is essential for sound attraction," the study stated.

"Males were unresponsive to the 400 Hz tones at all amplitudes tested, further demonstrating the profound effect of the mutation on responding to auditory stimulation," it added.

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How does it stop the spread of diseases?

Female mosquitoes spread diseases to nearly 400 million people every year. Scientists posit that trying to prevent them from having babies would help reduce the overall numbers. If the males cannot copulate, there will be no fertilisation and no eggs for the new mosquitoes.

Apart from making the males deaf, scientists are also exploring the possibility of releasing sterile males in areas where there are pockets of mosquito-spread diseases.