Can Mosquitos Stop Viruses Spreading?

From Zika to malaria, mosquitos are global carriers of viruses and disease. But according to a team of researchers from Australia's Monash University, they could also be a powerful weapon in the fight against outbreaks.

Trialled in the Australian city of Townsville, the large-scale project saw Dengue fever outbreaks halted by release of mosquitoes infected with Wolbachia bacteria, a genus of Gram-negative that inhibits the insects' ability to transmit viruses. The technique has prevented all outbreaks of dengue fever in Townsville over the past four years and now scientists are optimistic the same model can be used to combat epidemics like Zika, which is a major problem for cities like Rio de Janeiro.  

“I’m ecstatic,” says Scott O’Neill, director of Monash University's World Mosquito Program and leader of the Townsville project. “We’re wanting to have a really major impact on disease. For dengue and Zika nothing’s working at the moment for control. There’s evidence of a growing disease burden and there was the big Zika pandemic that stripped through the Americas recently and the rest of the world."

Trials set to hit Indonesia

The next trial will take place in Yogyakarta, an Indonesian city on the island of Java. O’Neill and his colleagues plan to conduct a randomised trial that will track and compare the disease burden of areas exposed to Wolbachia mosquitos, as well as unaffected control districts. Eventually the goal is to penetrate cities like Rio, though the sheer scale and population of over 1.5 million makes it a challenging project.

“Rio is one of the hardest places to work in,” says Scott. “The favelas are quite a challenge. If we can be successful in Rio we can probably be successful anywhere in the world.”

World Mosquito Program sets sights on malaria

While the current cost of the programme sits at around £8.50 per person, the team hope to make it available in less developed countries at a cost of just 75p. If the trials prove effective against Zika the World Mosquito Program hopes to target malaria, a mosquito-borne disease that currently affects over 200 million people and causes almost 450,000 deaths a year.

“There is lab data showing this approach could be effective in malaria as well, but that is much further upstream,” says O’Neill.

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