A Chinese factory is breeding 20
million male mosquitoes a week, and releasing them into nature to copulate with
wild female mosquitoes. Its aim—culling the population, and eradicating
disease.
A team of scientists, led by Xi
Zhiyong of China’s Sun Yat-sen University and Michigan State University,
announced in March, they are breeding mosquitoes that are infected with
Wolbachia bacteria, which produces infertile eggs when they mate with females
in the wild. Because the transmission of dengue and Zika is carried by
mosquitos, the release of these laboratory insects could stop the diseases from
becoming epidemics, the research team explains.
The world’s biggest “mosquito
factory,” with a total area of 3,500 square meters, and four workshops that
each can breed 5 million mosquitoes a week, has been established in southern
China’s Guangzhou city, where dengue fever strikes annually.
It is not clear where the male
mosquitoes will be released in the future. But the research team’s pilot
project released 500,000 Wolbachia-infected male mosquitoes to a small island
in Guangzhou in March of 2015. The mosquito population on the island had
dropped by half by June that year, Xi told the Beijing News at that time. Those
“500,000 mosquitoes sound a lot, but in fact, they’re like a drop in the
ocean,” Xi said.
Similar programs have been rolled out
in Australia, Vietnam, Brazil and Indonesia, and they are more effective, and
less expensive, than traditional methods of insecticide spraying, the Guardian
reported last year.
Wolbachia mosquitoes could have a
greater advantage over genetically
modified ones (another experimental way of controlling mosquito populations)
because genetic tweaks kill just one generation, while Wolbachia is passed on
to the next generation via infected females.
Early research shows Wolbachia does
not increase the risk of other pathogens being transmitted by mosquitoes, and
it is not harmful to the environment—but because mosquitoes are prey for birds
and fish, the long-term effects on the greater ecosystem are unclear.
The Chinese research team also plans
to build a mosquito factory in Brazil, Xi told a local newspaper recently.
Brazil launched its first trial of Wolbachia mosquitoes in 2014, and is now
throwing everything it has at the mosquito-borne epidemics ravaging the country.
Source : qz.com;
theguardian.com
