In an attempt to quell the Zika virus outbreak in South America, researchers are trying to infect mosquitoes with a special bacteria that could prevent them from spreading the virus (and it may work with other vector-borne diseases, too). Over the past few years, organizations have conducted research and field trials in Australia, Indonesia, and Vietnam have shown that this strategy could, in fact, be quite effective in reducing the risk for spreading the virus from insect to humans.
Indeed, the British and American governments have partnered with the Bill and Melinda Gates Foundation and the UK-based Wellcome Trust to expand on the existing field tests. USAID and the British government has also financially contributed.
The research revolves around the Wolbachia genus of bacteria. Tests show that this strain can, in fact, hamper the spread of virus when carried by mosquitoes. Now, the virus does not occur naturally in the tropical mosquito species Aedes aegypti which carries diseases like Zika as well as dengue fever, yellow fever, and chikungunya. And over the past decade, researchers have been finessing a way to encourage the Wolbachia bacteria into infecting this particular breed of insect in order to help prevent the spread of the various diseases it can carry.
“Using Wolbachia to reduce the transmission of mosquito-borne diseases has the potential to greatly reduce the global health burden and socio-economic cost of Zika and other related infections like dengue and yellow fever,” explains Mike Turner, who is the acting director of science and head of infection and immunobiology for the Wellcome Trust.
He goes on to say, “This research is essential as it will help measure the health impact of the Wolbachia method in large urban areas, where these kinds of outbreaks can have such a devastating impact.”
According to Prof Scott O’Neill, of the Eliminate Dengue Program, the Wolbachia bacteria is already present in a large number of insects around the world, insects that are already in direct and constant contact with humans and there has been no issue of dangerous infection. More importantly, though, he says, “And in the six years we have been doing these trials there have been no problems.”
Thus he continues, “We’ll know within a year, if these mosquitoes we’ve released, if they’re becoming common amongst the population. Then we’ll see simply by the number of people who get sick from either Zika or dengue. If those numbers come down quite substantially in these cities but not in other cities that’ll be the proof of this over a decade-long quest to use this intervention.”