Modern approaches to diagnosis and prevention of porcine reproductive and respiratory syndrome (review)

Introduction. Porcine reproductive and respiratory syndrome (PRRS), caused by a virus from the family Arteriviridae , is one of the most economically significant porcine diseases in many countries. The disease is mainly manifested by reproductive disorders in sows, i.e. abortions in late pregnancy, early or delayed farrowing, birth of weak or non-viable piglets, irregular estrus; pathologies in early and middle pregnancy are less often reported. Piglets and fattening pigs have respiratory distress syndrome: coughing, sneezing, dyspnea and stunted growth. In addition, infection with PRRS virus undermines respiratory immunity, which makes the infected pigs more susceptible to secondary infections and increases mortality in the herd. This review provides up-to-date information on the current laboratory diagnostic tools and recent data on specific PRRS prevention and gives information on the promising biotechnological platforms that can be used to design new-generation vaccines. Objective. To consider and summarize modern approaches to diagnosis and prevention of porcine reproductive and respiratory syndrome. Materials and methods. Scientific publications of foreign and domestic authors served as the material for the research. Results. The paper presents nosological characteristics of the disease, explores distinctive features of its clinical manifestations and epizootiology; analyzes structure of the pathogen’s genome. This review describes and evaluates laboratory diagnostic techniques (both conventional and modern); currently available anti-PRRS vaccines and novel biotech platforms enabling to design safer and more effective next-generation vaccines. There are three major challenges in vaccine development at the current stage of PRRS pathogenesis research: insufficient understanding of immune protection mechanisms, the virus’s ability to induce negative regulatory signals for the immune system, and the pathogen’s high antigenic variability. Conclusion. PRRS virus strains exhibit significant genetic and antigenic heterogeneity and frequently undergo recombination, which exacerbates the challenges of epizootiology, disease prevention, and control. Further in-depth study of host immune response characteristics, along with identification of T- and B-cell epitopes in the pathogen structure, will enable rational design of genetically engineered vaccines.