Could This Bacteria Breakthrough Block Zika and Dengue Transmission?

Scientists from Scotland have†discovered that bacteria may be used to block certain mosquito-transmitted viruses, including highly infectious and potentially deadly Zika and dengue.†

Previous research has†suggested that if mosquitoes carry a strain of Wolbachia bacteria,†they are less†able to transmit viruses like Zika and dengue, but scientists have struggled to produce an effective intervention — until now.

Engineering a solution†with bacteria is tricky for several reasons. In the lab, conditions are easy to control, but a number of variables complicate things in the real world. For example, tropical temperatures can inhibit or kill many strains of†non-native bacteria, making it more difficult to deploy††Wolbachia strains to fight Zika†and other mosquito-carried infections.

But†scientists at the University of Glasgow’s MRC Centre for Virus Research† believe they may have found a way forward.†Researchers have tested a form of the Wolbachia bacteria, called ‘wAu,’ that has proved to be highly effective at blocking virus transmission. What’s more, it appears to be resistant to tropical temperatures — something that will be critical†in†regions like South America.†

Dr.†Steve Sinkins, microbiology and tropical medicine specialist and lead researcher, explained:

The Wolbachia transmission blocking strategy shows great promise for the control of mosquito-borne viruses, and is now starting to be deployed on a large scale in a number of tropical countries. Our results with the wAu strain showed by far the effective transmission blocking for all the viruses we tested, and it provides an exciting new option to explore for disease control programmes.

To test†this bacteria, researchers†introduced four Wolbachia strains to mosquitoes that don’t naturally†carry the bacteria. Two of those strains had already been tested, so they provided a benchmark for evaluating the effectiveness of the two new†strains.

Researchers found†that after feeding on blood infected with dengue or Zika virus, mosquitoes carrying the wAu bacteria showed far lower levels of the virus than those†with other strains of bacteria. What’s more, mosquitoes appeared to pass on the bacteria to new generations, which could be key for†battling mosquito-borne infections in a cost- and time-effective way.

To put†this intervention into perspective, it’s important to understand†the impact of mosquito-borne illnesses.†These†arboviruses†include†dengue virus, West Nile virus, Japanese encephalitis virus, yellow fever virus, Crimean-Congo hemorrhagic fever virus and Zika.

For people who contract such viruses, the range of symptoms can be broad, but in their worst cases they may cause inflammation of the brain, organ failure, severe disability and death. But not everyone displays symptoms, meaning that they may suffer only very mild and easily missed symptoms,†while still†posing†an infection risk.†

Because it can take substantial time to control†an outbreak, it’s ideal to stop these viruses before they reach the human population.

Researchers around the world†continue to explore strategies for preventing Zika and dengue outbreaks. While the latest WHO figures from December of 2017 show that Zika is now largely under control, scientists are working to ensure there is no repeat of the high infection rate†from the†previous two years. Similarly, other researchers†are attempting to prevent†dengue‘s†spread with†vaccines and other measures.

This fight has a new urgency for many Western nations, as climate change may enable†mosquito-borne illnesses and other tropical diseases to†reach new regions.

While it won’t†be a magic bullet, researchers†remain encouraged that†the wAu innovation could form the basis of future interventions†to significantly reduce the spread of deadly mosquito-transmitted viruses.

Photo Credit: Agencia Brasilia/Flickr

43 comments

Marie W
Marie W19 days ago

Tks for sharing.

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Mike R
Mike R5 months ago

Thanks

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heather g
heather g6 months ago

Scotland deserves our thanks. Most countries can't be bothered about finding solutions to diseases that affect poorer countries in Africa and elsewhere.

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John B
John B6 months ago

Thanks Steve for sharing the information.

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Mike R
Mike R6 months ago

Thanks

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Mike R
Mike R6 months ago

Thanks

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Mike R
Mike R6 months ago

Thanks

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Winn A
Winn A6 months ago

Noted

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Ruth S
Ruth S6 months ago

Thanks.

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Ellie M
Ellie M6 months ago

ty

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