‘Beating the next pandemic with Wolbachia’

Scott O’Neill

As we enter the third year of the COVID-19 pandemic, there is growing frustration over the lack of an effective global response to this unprecedented crisis. The recent emergence of the Omicron variant has underscored the risks that all nations face when they fail to follow the science and fight for equitable, high-impact solutions to the world’s most pressing health challenges.

If COVID-19 has taught us anything, it is that the universal right to health is not just a noble aspiration — a lofty multilateral goal to be achieved at some far-flung date — it is an urgent strategic imperative for an increasingly interconnected and rapidly changing world. Omicron has defeated the most rigorous national testing protocols, proving yet again that pandemics show no regard for international borders.

But COVID-19 is not the only urgent disease threat facing the global community, and if we want to save lives and strengthen the resilience of our health systems, it is essential to invest now in the tools that can stop future pandemics from happening. The good news is that science has given us a powerful new line of defence against dozens of potential pathogens carried by mosquitoes. It’s a safe, effective, affordable and environmentally friendly innovation called Wolbachia.

Wolbachia is a common type of bacteria that thrives naturally in the cells of about 60 per cent of all insect species — including bees, fruit flies, butterflies and moths. In all likelihood, these insects have been living in stable symbiosis with Wolbachia for millions of years. But what makes Wolbachia an exciting public health breakthrough is the fact that when it is transferred to the cells of mosquitoes, it blocks them from transmitting dengue, chikungunya, Zika, yellow fever, and potentially dozens of other mosquito-borne viruses to humans.

Female mosquitoes also pass Wolbachia down to their offspring, allowing the bacteria to establish itself across mosquito populations over time, eliminating their ability to cause disease and creating a sustainable barrier against future outbreaks.

The New England Journal of Medicine recently published the results of a gold-standard randomised controlled trial in Yogyakarta, Indonesia, demonstrating that the introduction of Wolbachia collapsed dengue incidence by 77 per cent and dengue-related hospitalisations by 86 per cent in just three years. We can expect that dengue in Yogyakarta will decline toward zero over the next few years as Wolbachia-carrying mosquitoes become fully established. The introduction of Wolbachia in Queensland a decade ago has effectively eliminated dengue in Australia.

The need for Wolbachia has never been greater. In 2019, the World Health Organization (WHO) identified dengue as one of the 10 biggest threats to global health. Its incidence has grown 30-fold since the 1960s, and until now there have been no safe and effective ways to fight it. Dengue currently infects up to 400 million people per year, and four billion people in 129 countries across the tropics and subtropics live at direct risk of infection.

Dengue also exacts terrible social and economic costs. Like COVID-19, periodic outbreaks flood hospitals with patients and strain healthcare systems to their breaking points. The disease also drains billions of dollars from national healthcare budgets each year, pushes low-income families into poverty by saddling them with unaffordable medical bills, and steals billions of productive hours from workplaces and schools.

Wolbachia can address this challenge, and research from Indonesia indicates that for every dollar invested it can deliver more than $US3 in social and economic benefits. This means that Wolbachia pays for itself over time and stimulates equitable economic growth. With the rapid urbanisation of the Asia-Pacific region over the next few decades, the challenge of dengue — and the threat posed by other rapidly emerging mosquito-borne viruses like Zika — will only increase.

Wolbachia has already been deployed in 11 countries across Asia, Oceania, and the Americas with support from Australia’s Department of Foreign Affairs and Trade and with generous funding from philanthropies. The World Mosquito Program is committed to transferring the knowledge and tools required to successfully implement Wolbachia to all dengue-affected countries at the lowest possible cost, and works in partnership with national, local and municipal governments to help deliver an effective solution to one of their greatest health challenges.

It’s time to let science lead the way to a better future. With Wolbachia, we can prevent future pandemics and help end the scourge of mosquito-borne viruses for good.

Scott O’Neill is the founder and CEO of the World Mosquito Program. He was formerly the Dean of Science at Monash University.