A key weapon against Zika virus could be flying around Australia now.
The team of Professor Scott O’Neill, program director of Melbourne-based international collaboration Eliminate Dengue, said they are discussing with South American governments how their work could help combat the latest pandemic making rounds around the globe.
The team pioneered a biological control against the virus causing dengue, which is closely related to Zika. The mosquito-transmitted virus infects about 390 million individuals globally each year.
The secret weapon is called Wolbachia, a commonly occurring bacterial species naturally found in over 60 percent of insects. It is injected into mosquitoes to prevent them from being infected with RNA viruses, which happens to include the dengue and Zika arboviruses.
The bacteria inoculate the mosquitoes against the virus, where treated populations outcompete their virus-carrying counterparts and greatly reduce their numbers.
"We have done the experimental work and it's currently winding its way through pre-publication," reported O'Neill in an interview, although declining to specify which South American countries they are coordinating with at the preliminary stage.
The Wolbachia can only be transferred among mosquitoes inside female eggs – when an infected male mates with an uninfected female, it hinders such eggs from hatching. An infected female mosquito will reproduce normally, slowly spreading the numbers of the Wolbachia-infected kind.
Mosquito bites will remain a source of annoyance, but will not transmit infections in this case.
O’Neill emphasized the need to be “realistic” in addressing Zika using this strategy, knowing that implementing such widespread effort in a short timeframe is “a very difficult thing to do.”
Small-scale Wolbachia trials began in 2011. They have been so far conducted in Queensland in Australia as well as in Indonesia, Vietnam, Colombia, and Brazil, which is most heavily hit by Zika and logged most cases of birth defects linked to the infection.
The largest trial at present started in 2014, with scientists releasing Wolbachia-laced mosquitoes in Townsville.
Australia currently has two confirmed cases of Zika, but O’Neill said the potential for a large outbreak is very small.
Photo: Army Medicine | Flickr