Immunogenicity and efficacy of a bivalent vaccine against infectious bronchitis virus

Effect of monovalent and bivalent live attenuated vaccines against QX-like IBV infection in young chickens

“…Several alternative options have been applied to provide broad protection against variant IBV strains, including recombinant vaccine ( Li et al, 2016 ), nanoparticle-based vaccine ( Li et al, 2018 ), epitope-based vaccines ( Qin et al, 2021 ), etc., but they have yet to be administrated with mass hatchery application. In addition, considering multi-monovalent live attenuated vaccines, though several research showed efficacy in control different IBV strains in a laboratory scale ( Shao et al, 2020 ; Abdel-Sabour et al, 2021 ), it still raises many issues including the frequency of combination among field and vaccine strains ( Bali et al, 2021 ). Therefore, proper selection of the vaccine and vaccination strategy is highly important to control the disease in the field.…”

“…However, due to lack of cross-protection in most IBV commercial vaccines, vaccination with a single vaccine usually provide less protection against IBV strains with different serotypes ( Gao et al, 2016 ). Though recombination of multiple vaccines covering different serotypes was reported to show broad protective spectrum ( Zhao et al, 2015 ; Abdel-Sabour et al, 2021 ), the risk of recombination within live virus strains still exists. In order to identify better vaccination for day-old chickens, this study applied several heterologous monovalent and bivalent live attenuated vaccines and evaluated the protection conferred by these vaccines against the predominant QX-like (GI-19) IBV.…”