We have all scratched at itchy bug bites or slapped at a whining noise in our ears only to find nothing there. These are the calling cards of mosquitoes, animals that annoy humans to no end.
But, to the people of Africa, Central America, and South America, mosquitoes are more than just nuisances – they are agents of disease, spreading sicknesses like dengue fever and Zika virus.
Scientists from the Commonwealth Scientific and Industrial Research Organization (CSIRO) and James Cook University have managed to wipe out huge numbers of disease-carrying mosquitoes in the Australian state of Queensland.
How Did They Do It?
To answer that question, we need to go back to the 1950s, when the Sterile Insect Technique was pioneered by Raymond Bushland and Edward Knipling.
The two needed a way to get rid of screw-worm flies that would prey on cattle. They developed a process where they took male flies, sterilized them in a lab, and then released them into the wild. The sterile flies would then mate with female flies; however, no resulting offspring would be produced. In this way, the next generation would have a much smaller population. With this technique, Bushland and Knipling saved over $200 million in American meat and dairy supplies.
The technique has only ever been used with species of flies, until now. In this trial, the Australian scientists targeted the Aedes aegypti, a mosquito species native to Africa.
Wiping Out Mosquitoes
They may be small but mosquitoes are responsible for nearly 1 million deaths each year. It is not the mosquito bite itself, but the parasites they carry that transmit diseases like malaria. The Aedes aegypti is one of the three most dangerous types of mosquitoes. The female of the species is responsible for life-threatening diseases like dengue, Zika, and chikungunya. These mosquitoes thrive in warm climates and in populated areas.
So far, pesticides and habitat destruction have proven inefficient in killing mosquitoes. Further, vaccines cannot effectively combat the diseases mosquitoes spread. Researchers in Australia bred and sterilized 20 million of the male mosquitoes by injecting a bacteria known as Wolbachia. The sterile males were released in three towns on the Cassowary Coast. It was a smashing success. Over 80% of the mosquitoes were wiped out.
The idea of sterilizing male mosquitoes is not new and has been used with limited success in Florida. However, the technology to create large batches of sterile male mosquitoes was pioneered by Verily - a division of Alphabet, Google's parent company. Verily's robot can produce as many as 1 million sterile mosquitoes a week and was deployed last year in Folsom, California. Scientists in Australia used Verily's technology to complete the recent trial scenarios.
Sterilizing mosquitoes may seem like a small step towards saving lives, but the effects it will have on healthcare could be life-changing for the many who view mosquitoes as not just an inconvenience, but an assassin. With this new weapon in our arsenal, we can treat the root causes of the diseases instead of their symptoms.
Sources: Newsweek, NPR, Wikipedia, IAEA, FAO,