Vaccines
All COVID-19 vaccines in this study were developed based on the SARS-CoV-2 wild-type strain (Wuhan-Hu-1 strain) isolated in December 2019. Ad5-nCoV (Convidecia) is a replication-defective human type 5 adenovirus-vectored vaccine, encoding the full-length Spike gene of the Wuhan-Hu-1 strain (YP_009724390) (