Assessment of the Risk of Exotic Zika Virus Strain Transmission by and from Senegal Compared to a Native Strain.

Zika virus (ZIKV) shows an enigmatic epidemiological profile in Africa. Despite its frequent detection in mosquitoes, few human cases have been reported. This could be due to the low infectious potential or low virulence of African ZIKV lineages. This study sought to assess the susceptibility of and to ZIKV strains from Senegal, Brazil, and New Caledonia. Vertical transmission was also investigated. Whole bodies, legs/wings and saliva samples were tested for ZIKV by real-time PCR to estimate infection, dissemination and transmission rates as well as the infection rate in the progeny of infected female . For , the Senegalese strain showed at 15 days post-exposure (dpe) a significantly higher infection rate (52.43%) than the Brazilian (10%) and New Caledonian (0%) strains. The Brazilian and Senegalese strains were disseminated but not detected in saliva. No offspring from females infected with Senegalese and Brazilian ZIKV strains tested positive. No infection was recorded for . We observed the incompetence of Senegalese to transmit ZIKV and the were completely refractory. The effect of freezing ZIKV had no significant impact on the vector competence of from Senegal, and vertical transmission was not reported in this study.