Aedes aegypti mosquitoes from Burkina Faso can transmit the chikungunya virus and Zika virus of the African lineage, but not the Zika virus of the Asian lineage.

Abstract

Aedes aegypti is the primary vector for the transmission of dengue virus (DENV), Zika virus (ZIKV), and chikungunya virus (CHIKV). While Burkina Faso has been facing an increase in DENV epidemics, no ZIKV or CHIKV outbreaks have been reported. Here, we, therefore, assessed the vector competence of Ae. aegypti mosquitoes from Burkina Faso for ZIKV and CHIKV transmission. Ae. aegypti mosquitoes from urban and peri-urban sites of Ouagadougou were orally infected via blood meal with different titres of a West African CHIKV strain and ZIKV strains of the Asian and African lineage. The infection rate for mosquitoes from both sites was ~65% for CHIKV, whereas the dissemination was 85% and 45%, respectively, in urban and peri-urban mosquitoes. The CHIKV transmission rates ranged between 14 and 18%. For the African lineage of ZIKV, the infection rate was higher for urban mosquitoes than peri-urban mosquitoes (100% vs. 80%), whereas the dissemination rate was 100% in mosquitoes from both sites. The transmission rates for African ZIKV ranged between 12 and 18% for both urban and peri-urban mosquitoes. In contrast to ZIKV of the African lineage, low infection rates (10-30%) and dissemination rates (14-50%) were observed with the Asian lineage of ZIKV. Additionally, mosquitoes from both sites could not transmit the ZIKV strain of the Asian lineage. This study demonstrates, for the first time, the capability of Ae. aegypti mosquitoes from Burkina Faso to transmit chikungunya virus and the pre-epidemic strain of Zika virus in their saliva, highlighting the importance of establishing surveillance for these viruses in Burkina Faso.