How Wolbachia bacteria could help us tackle some of the world’s most neglected tropical diseases

The animals that pose the biggest threat to humans are not lions, sharks, or snakes; they are tiny mosquitoes. Mosquitoes kill more than 600,000 people every year from malaria alone, but they also carry and spread a host of other tropical diseases.

One of those is dengue fever. It’s a common disease found in the tropics and subtropics, and around 60 million recorded cases occur each year.

For most people, the symptoms of dengue fever are extremely unpleasant: a fever, severe headache, nausea, joint and muscle pain, and sometimes a rash. Some die from it. Around 25,000 people die from dengue each year, almost all of them in Asia. To put this in perspective, in most years over the past decade, fewer than 25,000 people died globally in all natural disasters combined.1 Ending dengue fever would be like ending the death toll from floods, wildfires, hurricanes, and other disasters.

Unlike some other tropical diseases, dengue fever has no specific antiviral treatment, and while vaccines exist, none provide universal protection comparable to vaccines for diseases like measles or polio.

However, one promising solution could dramatically reduce the spread of infections and the number of people experiencing a severe form of the disease: the Wolbachia method.

Wolbachia is a tiny bacterium that naturally occurs in around half of all insect species, including fruit flies, bees, beetles, moths, dragonflies, butterflies, and some mosquitoes.

The mosquito most commonly spreading dengue fever — Aedes aegypti — doesn’t naturally contain Wolbachia. But scientists discovered that when these mosquitoes are bred to carry it, they are much less likely to transmit viruses from person to person. This doesn’t just apply to dengue fever but also to other diseases such as yellow fever, Zika, and chikungunya. This new method promises to finally give humanity an effective tool against several tropical neglected diseases.

In this article, I’ll focus on how Wolbachia can be used against dengue fever. I'll examine how this innovative new method works, how effective it is in reducing transmission, and how it can be rolled out across the tropics to protect as many people as possible.