Evaluation of Four Commercial Vaccines for the Protection of Piglets against the Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus (hp-PRRSV) QH-08 Strain

Abstract

Vaccination is the best way to prevent economic losses from highly pathogenic porcine reproductive and respiratory syndrome virus (hp-PRRSV) disease. However, the commercially available vaccines need to periodically evaluate their efficacy against infections caused by new hp-PRRSV variants. Therefore, the objective of this study was to evaluate the efficacy of four (two modified live vaccines (MLV) and two inactivated) PRRSV commercial vaccines in piglets challenged with QH-08 and to estimate the genetic distance of the vaccine strains from recently isolated (QH-08) filed strain. Randomly, piglets (n = 5) allocated in groups 1–4 were immunized with Ingelvac PRRS MLV, CH-1a, JXA1, and JXA1-RMLV vaccines, whereas the infected and non-infected control piglets in groups 5 and 6 (n = 3), respectively, were subjected to PBS. Results indicated that JXA1 and JXA1-R MLV vaccines showed complete protection, but Ingelvac PRRS MLV and CH-1α vaccines revealed partial protection against the QH-08 PRRSV challenge. Similarly, vaccinated and challenged pigs showed lower macroscopic and microscopic lesions than the pigs in group 5. Our findings demonstrated a new insight that the variation in ORF1a and 1b coding sequence could significantly affect PRRSV vaccines efficacy. In conclusion, QH-08 is a good candidate for the design and development of an innovative PRRSV vaccine that ultimately helps in the control and prevention strategies.

Genome-Wide Characterization of QYYZ-Like PRRSV During 2018–2021

“…According to the results of this study and previous studies, QYYZ-like strains have been occasionally reported in northern China ( 19 , 26 , 28 , 53 ) but are mainly prevalent in southern and central China ( 12 – 16 , 23 – 25 , 27 , 29 , 30 , 32 ). Although recombination of PRRSV is very common, many non-recombination strains of JXA1-like ( 54 ), VR2332-like ( 28 ) and NADC30-like/NADC34-like PRRSV ( 7 , 55 ) have been reported after long-term evolution in China. All QYYZ-like strains were recombined with other lineages of PRRSV except the prototype strain QYYZ.…”

Epidemiological investigation and pathogenicity of porcine reproductive and respiratory syndrome virus in Sichuan, China

“…Nevertheless, given the prevalence of PRRS, vaccination remains the primary approach available. Commercially available vaccines in China include CH-1a/CH-1R, R98/R98 MLV, VR2332/Ingelvac PRRS MLV, JXA1/JXA1-R, TJ/TJM-F92, HuN4/ Hun4-F112, GD/GDr180, and among others ( Leng et al, 2017 ; Wang H. M. et al, 2018 ; Ding et al, 2021 ). While these vaccines can partially control PRRS outbreaks and reduce the duration of clinical signs and viremia in pigs, they cannot provide full protection against PRRS infection, with vaccine efficacy limited to partial or modest protection against heterologous challenges.…”

Genomic similarity and antibody-dependent enhancement of immune serum potentially affect the protective efficacy of commercial MLV vaccines against NADC30-like PRRSV

“…Vaccination is important to prevent and control PRRSV and to eliminate PRRSV ( Chen N. et al, 2021 ; Jeong et al., 2021 ). Although the PRRSV vaccine has a good protective effect against homologous strains, its protective effect against heterologous strains is incomplete ( Chen X. et al, 2021 ; Ding et al., 2021 ; Li Y. et al., 2021 ). In this study, immunization with an MLV vaccine provided some protection against NADC30-like PRRSV SX-YL1806 in piglets, including an improvement in temperature, ADG level, viremia, and lung tissue virus load ( Fig.…”