Natural infection of Aedes albopictus with the wAlbB strain and Ae. aegypti with the wPip strain of Wolbachia in Iran.

The global resurgence of Aedes-borne arboviruses (dengue, chikungunya, and Zika) underscores the need for innovative vector control strategies. In Iran-a region at risk for arbovirus emergence due to invasive Aedes albopictus and Ae. aegypti mosquitoes- we investigated the natural occurrence of Wolbachia infections. Screening of field-collected and laboratory-reared mosquitoes revealed the presence of two Wolbachia strains: wAlbB in Ae. albopictus and wPip in Ae. aegypti. Notably, detection of wPip in the wild Ae. aegypti represents a potential first report globally, as this species has been historically considered uninfected in natural populations. Wolbachia prevalence was significantly higher in laboratory-reared mosquitoes and Ae. albopictus. Multivariable analysis confirmed that Ae. aegypti had significantly lower odds of Wolbachia infection compared to Ae. albopictus (adjusted OR = 0.12, 95% CI: 0.03-0.45, p = 0.002), and infection odds were also significantly lower in field-collected mosquitoes from Guilan (OR = 0.28), Mazandaran (OR = 0.05), and Hormozgan (OR = 0.14) provinces relative to insectary-reared specimens (all p < 0.05). These findings provide critical baseline data for evaluating the feasibility of Wolbachia-based interventions in Iran, where invasive Aedes populations could facilitate arbovirus transmission. This study highlights the importance of characterizing native Wolbachia infections to inform future biocontrol strategies against emerging mosquito-borne diseases.