About
Zika virus (ZIKV) is an arbovirus transmitted to humans by Aedes (Ae.) mosquitoes. ZIKV became a major public health problem in 2013-15 with epidemics in French Polynesia and then in Latin America. Emergence of epidemic ZIKV strains of Asian genotype has been associated with unprecedented severe congenital anomalies in pregnant women grouped together under the umbrella term Congenital Zika Syndrome (CZS) with teratogenic effects presenting as microcephaly and other adverse perinatal complications associated with a high risk for developmental disorders at birth. ZIKV can be detected in human biological fluids such as ocular secretion, urine and semen for prolonged periods after the infection. The virus raises concerns about risk of sexual transmission in relation with persistent viral infection in human testis tissue. The risk of CZS remains poorly documented in Africa where ZIKV strains of the African genotype are distinct from the Asian genotype. West Africa ZIKV strains that have been recently identified as highly teratogenic can be efficiently transmit by Ae. aegypti. Asian tiger mosquito Ae. albopictus have already colonized a large part of Europe including mainland France and La Reunion Island (Indian ocean). African ZIKV strains represent a potential risk of emergence in tropical and temperate zones where Ae. albopictus is increasingly present. The CAZIKANO project, which brings together eight multidisciplinary teams in France and Australia under the coordination of UMR PIMIT in Réunion, proposes to assess the risk of emergence of the African ZIKV genotype through the integrative study of two West Africa viral strains that have isolated from a pool of mosquitoes in Senegal in 2011 and individual infected by ZIKV in Guinea in 2018. The two viruses will be characterized for (i) their dynamic interaction with Ae. mosquito vectors and their capacity to escape midgut barrier in Ae. species and Drosophila model, (ii) their ability to replicate and initiate persistent viral infection in human host-cells involved in viral pathogenesis, and (iii) sensitivity to natural extracts in order to identify antiviral natural compounds. The CAZIKANO proposal will provide important information on the risk of vectored and non-vectored dissemination of contemporary ZIKV strains of African lineage with the view to rationalize the development of bioactive antiviral compound analogs.
