Development of a subunit vaccine candidate (RBD-HA trimer) provides dual protection against multi-subtype avian influenza viruses and QX-type infectious bronchitis virus.
A chimeric subunit vaccine, RBD-HA, in which the receptor-binding domain of the QX-type IBV spike protein replaced the immunodominant head domain of H9N2 AIV haemagglutinin is developed, providing proof of concept for a bivalent subunit vaccine targeting two major avian respiratory viruses.