Virus evolution in <i>Wolbachia-</i> infected <i>Drosophila</i>

Abstract

<i>Wolbachia</i>, a common vertically transmitted symbiont, can protect insects against viral infection and prevent mosquitoes from transmitting viral pathogens. For this reason, <i>Wolbachia-</i>infected mosquitoes are being released to prevent the transmission of dengue and other arboviruses. An important question for the long-term success of these programmes is whether viruses can evolve to escape the antiviral effects of <i>Wolbachia.</i> We have found that <i>Wolbachia</i> altered the outcome of competition between strains of the DCV virus in <i>Drosophila.</i> However, <i>Wolbachia</i> still effectively blocked the virus genotypes that were favoured in the presence of the symbiont. We conclude that <i>Wolbachia</i> did cause an evolutionary response in viruses, but this has little or no impact on the effectiveness of virus blocking.