US MULLING PLAN TO INFECT MOSQUITOES WITH BACTERIA TO CURB ZIKA VIRUS
The US may soon become the first nation to approve the commercial use of a common bacterium to fight the spread of diseases such as the Zika virus. The strategy would involve infecting mosquitoes with the bacteria and releasing the males into the environment.
The idea, currently being reviewed by the Environmental Protection Agency (EPA), comes from MosquitoMate, a biotechnology startup which hopes to use the Wolbachia pipientis bacteria as a tool against the Asian tiger mosquito (Aedes albopictus), Nature reported.
The company’s plan involves rearing mosquitoes infected with a particular strain of the bacteria and releasing the males into the environment. If the males mate with females who do not carry the same strain of Wolbachia, any fertilized eggs would not hatch because the paternal chromosomes would not form properly.
This, according to MosquitoMate – a company started by researchers at the University of Kentucky – would result in a dwindling mosquito population and consequently less spread of diseases.
The current proposal being reviewed by the EPA comes after three years of testing by MosquitoMate, in three different states. The strategy has so far reduced the wild mosquito population by more than 70 percent in those areas, according to Stephen Dobson, an entomologist at the University of Kentucky and founder of the company.
In addition to using Wolbachia to target the Asian tiger mosquito, MosquitoMate is also using it to target the Aedes aegypti mosquito, thought to be the main vector for the Zika virus. The company began field trials of infected A. aegypti mosquitos in Clovis, California earlier this month, and has applied to conduct similar tests in Florida and Orange County, California.
Researchers hope that targeting mosquitoes with Wolbachia will lead to less spread of Zika, dengue, and Chikungunya, among other viruses.
The EPA’s decision on MosquitoMate’s application will come after a public comment period that ends on May 31.
Meanwhile, other groups are also investigating how to defeat the Aedes aegypti mosquito. Researchers from Sun Yat-sen University in Guangzhou, China, and Michigan State University began field trials of Wolbachia-infected mosquitos last year in Guangzhou. The researchers are releasing 1.5 million male Aedes aegypti per week, and plan to increase that number to five million per week by the end of August.
“Our mosquito factory is currently the largest one in the world,” said Zhiyong Xi, a medical entomologist and microbiologist at Michigan State University, who oversees the project.
It comes just weeks after a Brazilian study found that Wolbachia significantly reduced the ability of mosquitoes to transmit the Zika virus, a close relative of dengue, which has been linked to the birth defect microcephaly. The virus has swept through South and Central America and the Caribbean, making its way north to the US.
On Tuesday, the World Health Organization (WHO) admitted that it is partially responsible for the outbreak of the Zika virus, saying it had failed to introduce mosquito control policies over the last few decades.