CFB and Recurrent lower respiratory tract infections: Unlike the Beta-specific COH04S351 vaccine, the BA.1-specific COH04S529 conferred consistently improved efficacy compared to COH04S1 to protect against weight loss, lower respiratory tract infection, and lung pathology during early phase (at day 4) following homologous challenge with BA.1, while all three vaccines conferred comparable levels of protection against heterologous challenge with BA.2.12.1.