Evaluation of Coinfection and Superinfection Impact on Chikungunya and Mayaro Virus’s Replication in Aedes aegypti

The co-occurrence of different arboviruses, through (re)emergence episodes in a particular region, often exacerbates public health crises associated with these pathogens. Considering the Brazilian epidemiological panorama of arboviruses cocirculation, such as Dengue (DENV), Zika (ZIKV), and Chikungunya (CHIKV) viruses, the imminent emergence of Mayaro virus (MAYV) in urban areas, and the presence of susceptible human hosts, we looked into the coinfection and superinfection impact of CHIKV and MAYV replication in Aedes aegypti. Mosquitoes were coinfected and superinfected with CHIKV and MAYV by artificial blood-feeding, and infection (IR), dissemination (DR), transmission (TR) rates, and viral load were evaluated by qRT-PCR. Our findings suggest that, Ae. aegypti can simultaneously transmit CHIKV and MAYV in coinfection scenarios. However, in superinfection assays, the initial infection (either CHIKV or MAYV) adversely affected the transmission capacity of the subsequently acquired virus, indicating replication interference between the viruses. These results have important implications for public health management actions in the country, emphasizing complex arbovirus transmission scenarios and the associated epidemiological risks.