Research Progress on the Development of Porcine Reproductive and Respiratory Syndrome Vaccines

SIMPLE SUMMARY: Vaccine immunization measures are mainly adopted for porcine reproductive and respiratory syndrome (PRRS) prevention. We summarize the advantages, disadvantages, and applicability of currently developed PRRSV vaccines, including modified-live virus, inactivated, recombinant subunit, live vector, DNA, gene-deletion, synthetic peptide, and virus-like particle vaccines, as well as various other vaccines. These results provide a theoretical foundation for the development of new vaccines. ABSTRACT: Porcine reproductive and respiratory syndrome (PRRS) is a highly contagious disease in the pig industry, but its pathogenesis is not yet fully understood. The disease is caused by the PRRS virus (PRRSV), which primarily infects porcine alveolar macrophages and disrupts the immune system. Unfortunately, there is no specific drug to cure PRRS, so vaccination is crucial for controlling the disease. There are various types of single and combined vaccines available, including live, inactivated, subunit, DNA, and vector vaccines. Among them, live vaccines provide better protection, but cross-protection is weak. Inactivated vaccines are safe but have poor immune efficacy. Subunit vaccines can be used in the third trimester of pregnancy, and DNA vaccines can enhance the protective effect of live vaccines. However, vector vaccines only confer partial protection and have not been widely used in practice. A PRRS vaccine that meets new-generation international standards is still needed. This manuscript provides a comprehensive review of the advantages, disadvantages, and applicability of live-attenuated, inactivated, subunit, live vector, DNA, gene-deletion, synthetic peptide, virus-like particle, and other types of vaccines for the prevention and control of PRRS. The aim is to provide a theoretical basis for vaccine research and development.