5. Current animal models for MERS-CoV infections and vaccine evaluation Vaccine candidates that have proved effective against MERS-CoV infections in vitro culture conditions need to be evaluated ineffective animal challenge models to confirm protective immunity.MERS-CoV has been shown to cause transient lower respiratory tract infection in rhesus macaques, and infected monkeys demon-strated clinical signs of diseases, virus replication, histological lesions and neutralizing antibody generation