OREANDA-NEWS  The devastating effects of Zika virus (ZIKV) on developing human fetuses have created a need to identify new treatments and methods to prevent large outbreaks. To that end, scientists have tried to target ZIKV at every stage of the viral life cycle, including attempts to limit the capacity of ZIKV to infect and replicate in the Aedes mosquito vector. One innovative approach has been to infect mosquitos with Wolbachia, a mutualistic bacterium that resides within arthropods. Prior studies have shown that Wolbachia restricts ZIKV infection in mosquitos, so Wolbachia colonization of mosquito populations may help to prevent large outbreaks. However, one previously confirmed anti-ZIKV strain of Wolbachia exhibits reduced maternal transmission and therefore may integrate less efficiently into mosquito populations.

In a recent issue of Journal of Virology, Schultz et al. set out to find alternative Wolbachia strains that may inhibit ZIKV replication in order to identify alternative anti-ZIKV Wolbachia strains. They infected mosquito cell cultures with different Wolbachia strains and found two Wolbachia strains that inhibit ZIKV replication in vitro, including wStri, which was isolated from a planthopper, and wAlbB, which was isolated from Aedes mosquitos. In their studies, the authors demonstrated that these Wolbachia strains blocked the very earliest stages of ZIKV RNA replication and that this may have occurred as a result of Wolbachia’s capacity to compete for nutrients that are required for efficient replication of ZIKV.

Exploitation of Wolbachia is one strategy for limiting the spread of Dengue virus, a flavivirus that is closely related to ZIKV. The deployment of Wolbachia-infected mosquitos to decrease viral transmission has already begun in multiple cities, including Rio de Janeiro. This new study by Schultz et al. provides additional mechanistic insight into the possibility of a better anti-ZIKV Wolbachia. But first, in vivo studies are still required to determine whether these cell cultures findings can be translated into nature.