Research progress on the molecular mechanism of immune escape of porcine reproductive and respiratory syndrome virus.

Porcine reproductive and respiratory syndrome (PRRS), caused by the porcine reproductive and respiratory syndrome virus (PRRSV), is a severe and highly contagious disease that results in significant economic losses for the pig industry. Currently, vaccination is one of the most effective methods for controlling PRRS; however, due to the extensive genetic variation of PRRSV and the generation of homologous immunity, vaccines provide protective effects only against homologous strains and lack effective cross-protection against heterologous strains. Furthermore, PRRSV encodes a variety of proteins with immune escape functions, and the mechanisms underlying these functions are complex and not yet fully understood. This complexity presents substantial challenges to the prevention, control, and eradication of the disease. Therefore, this article reviews the various escape mechanisms of PRRSV identified in recent years, with the aim of providing insights into the pathogenic mechanisms of PRRSV and facilitating the development of safer and more effective vaccines and therapeutics.