Scientists at the University of Glasgow's MRC Centre for Virus Research (CVR) have found a new bacterial strain to be more effective than existing ones in blocking dengue and Zika virus transmission from mosquitoes.
In a new study published in the PLOS Pathogens journal last week, the scientists showed that a novel strain of the inherited bacteria Wolbachia strongly blocks transmission of dengue and Zika virus among infected mosquitoes, offering a potential alternative to strains already being tested as virus control tools.
The research was carried out in the Aedes aegypti mosquito species, which spreads a number of dangerous human viruses, including dengue, Zika, and Chikungunya.
Past research has shown that transmission of these viruses among mosquitoes is inhibited if the flies are deliberately infected with one strain of Wolbachia bacteria, and several countries are testing whether infecting local mosquito populations with Wolbachia could lower rates of viral disease in humans.
Now, the CVR scientists have now demonstrated that the novel “wAu” strain is even more effective for virus transmission blocking than strains currently being used, particularly in hot, tropical climates where there is high prevalence of these diseases. While several Wolbachia strains have been tested in the field, some strains may not block transmission effectively and at high ambient temperatures.
Professor Steven Sinkins of the CVR said: “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."
Future research could explore strategies to maximise the effectiveness of wAu in the field, such as combining it with a second strain to help it spread throughout local mosquito populations.