Detection and genetic diversity of Wolbachia and its associated prophage WO in mosquito populations from Ethiopia

Abstract Arboviral diseases transmitted by mosquitoes, including dengue, Chikungunya, Zika, yellow fever, West Nile virus (WNV), and Rift Valley fever (RVF), pose a significant public health challenge globally, particularly impacting populations in low and middle-income countries. Conventional mosquito control methods, which primarily rely on insecticides, face critical challenges, including the development of insecticide resistance and environmental concerns. In this context, Wolbachia, an endosymbiotic bacterium, presents an alternative strategy due to its ability to manipulate mosquito reproduction and impede the transmission of pathogens. This study aimed to detect and assess the genetic diversity of Wolbachia and prophage WO in Ethiopian mosquitoes. Mosquitoes were collected from various ecological niches in the Great Rift Valley. Molecular analyses were performed to identify the presence of Wolbachia using PCR targeting the 16 S rRNA and wsp genes. Additionally, the presence of prophage WO was assessed by detecting the conserved orf7 capsid protein gene. To understand genetic diversity, phylogenetic and genetic diversity analyses were performed. Wolbachia was detected in 44.2% (34/77) of mosquitoes using the 16 S rRNA gene and 46.8% (36/77) using the wsp gene. The highest prevalence was observed in Cx. pipiens complex (100%, 11/11) and Ma. uniformis (92.3%, 12/13). Prophage WO was detected in 46.8% (36/77) of mosquitoes, with evidence of multiple-strain co-infections in Cx. pipiens complex. Phylogenetic analysis classified all isolates within Wolbachia pipientis Supergroup B. This study provides the first preliminary characterization of Wolbachia and prophage WO in Ethiopian mosquitoes, revealing evidence of genetic diversity. These findings lay the conceptual foundation of potential Wolbachia-based vector control strategies in Ethiopia and underscore the need for further studies on strain-specific impacts on vector competence and arboviral transmission dynamics.