ERVW-1 and Zika virus infectious disease: These results indicate that our purified Asian-lineage ZIKV Env-CD4 recombinant protein can reliably detect anti-ZIKV Env antibodies in infected individuals, which may be relevant for sero-diagnosis of ZIKV infection, as well as its application in the monitoring of vaccine immunogenicity, during ZIKV vaccine clinical trials in healthy volunteers.