Interactions of chikungunya virus with Asian tiger mosquitoes (Aedes albopictus): vector competence and diversity of midgut bacteria

Chikungunya virus (CHIKV) is an important mosquito-borne virus. Previous studies have revealed the influence of midgut bacteria on infection with this pathogen. In this study, we examined the interactions of CHIKV with Aedes albopictus (Skuse) in terms of vector competence and the diversity of midgut bacteria. The diversity of midgut bacteria in CHIKV-infected and non-infected Ae. albopictus was observed after feeding with blood with different titers of CHIKV. CHIKV transmission rates on day 14 post-blood feeding in Ae. albopictus were 42%, 70%, 100%, 90% and 83% after being fed on 102, 103, 104, 105 and 106 TCID50/mL of CHIKV, respectively. Micrococcus was the dominant genus in CHIKV-infected mosquitoes fed at CHIKV titers of 102, 103, 105 and 106 TCID50/mL, but Bacillus was the dominant genus at 104 TCID50/mL. Non-infected mosquitoes differed from the CHIKV-infected mosquitoes fed at 103 and 105 TCID50/mL in that Staphylococcus was dominant. At the species level, Micrococcus luteus was the dominant species in Ae. albopictus fed on a CHIKV-negative blood meal, CHIKV non-infected mosquitoes fed on CHIKV at 102 TCID50/mL., and CHIKV-infected mosquitoes fed at CHIKV titers of 102, 103, 105 and 106 TCID50/mL.