Parasite might cause early death in mosquitoes

Queensland, Australia, January 24: Australian researchers have found out a way to make mosquitoes die naturally when young, to check the spread of diseases these pests cause when older.

Till now, scientists have been genetically engineering mosquitoes to effect resilience to illnesses such as malaria and dengue fever that afflict millions of people across the globe. This approach was being followed as a substitute to the mass spraying of insecticides.

A latest report has put forward a possibly simpler method; raising mosquitoes to hold and insect parasite that leads to its premature death.

It is worth mentioning here that all it takes is just one time for a mosquito to encounter malaria and dengue, after which it takes a mere 2 weeks of incubation before it can multiply the pathogens by stinging somebody. This implies that compared to the younger ones, the older of these pests can be more harmful.

The Australian scientists who conducted the study were aware of a type of fruit-fly that is generally infected with a strain of bacterial parasite. This parasite reduces its lifespan to half.

With this in mind, the researchers infected Aedes aegypti, the mosquito species responsible for dengue with that fruit fly parasite. As a result, they rose many such generations of the pest in a closely monitored laboratory.

Scott O’Neill, a biologist at the University of Queensland, reported in the journal ‘Science’ that mosquitoes, which were born with the parasite, were alive only for 21 days, even in cozy laboratory conditions. This is in contrast to 50 days for which a normal mosquito lives.

O’Neill deduced that if the parasite could spread sufficiently among these mosquitoes, then it might offer a cheaper approach to controlling dengue fever.

O’Neill’s team is gearing up to conduct longer studies on the subject in February. The team would undertake this research in special North Queensland mosquito facilities.

Andrew Read and Matthew Thomas, specialists at Pennsylvania State University, said in an editorial, “By killing old mosquitoes, wMelPop could thus impact on dengue transmission.” They described the study as “a major step”.

They observed that early death of their mosquito hosts could make the dengue viruses evolve to incubate at a faster rate, though it would not pose as much a problem as the present day insecticide resistance does.

The specialist duo warned, “Determining whether it can remove enough infectious mosquitoes to be useful will be a challenge.”