International Journal of Molecular Veterinary Research, 2025, Vol.15, No.1, 32-42 http://animalscipublisher.com/index.php/ijmvr 32 Research Report Open Access Pathogenesis and Molecular Diagnosis of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) Hui Liu1, JiaXuan2 1 Tropical Animal Medicine Research Center, Hainan Institute of Tropical Agricultural Resources, Sanya, 572025, Hainan, China 2 Animal Science Research Center, Cuixi Academy of Biotechnology, Zhuji, 311800, Zhejiang, China Corresponding author: jia.xuan@cuixi.org International Journal of Molecular Veterinary Research, 2025, Vol.15, No.1 doi: 10.5376/ijmvr.2025.15.0004 Received: 03 Jan., 2025 Accepted: 05 Feb., 2025 Published: 16 Feb., 2025 Copyright © 2025 Liu and Xuan, This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Preferred citation for this article: Liu H., and Xuan J., 2025, Pathogenesis and molecular diagnosis of porcine reproductive and respiratory syndrome virus (PRRSV), International Journal of Molecular Veterinary Research, 15(1): 32-42 (doi: 10.5376/ijmvr.2025.15.0004) Abstract Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is the economically most devastating agent targeting the world swine economy through reproductive failure in sows and respiratory distress in piglets. PRRSV, after its detection, has demonstrated great genetic diversity and evolutionary trends and has continued to offer challenges in prevention and control. This study globally summarizes current knowledge of the biological characteristics, infection process, and pathogenic tactics of PRRSV, particularly virus entry, replication, and immune evasion processes. Furthermore, it emphasizes the complex interaction between PRRSV and host immunity, such as interferon signaling down-regulation and adaptation immune response manipulation. Advances in molecular diagnostic technologies such as quantitative PCR, RT-LAMP, next-generation sequencing, and point-of-care tests are discussed in terms of their sensitivity, specificity, and potential for rapid field deployment. New studies on PRRSV molecular evolution and phylogenetic monitoring have provided new insights into viral recombination and transmission dynamics. While significant progress has been made, key challenges remain to elucidate the entire pathogenic mechanisms, align molecular diagnostic assays, and bridge gaps between basic research and successful control of the disease. The strategies forward need to be to integrate genomics and multi-omics technologies to enhance PRRSV pathogenesis, improve diagnostic performance, and guide development of next-generation vaccines and control strategies. Keywords Porcine reproductive and respiratory syndrome virus (PRRSV); Pathogenic mechanism; Molecular diagnosis; Immune evasion; Genomic evolution 1 Introduction Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) appeared in the late 1980s following outbreaks of a swine disease of unknown cause that had previously not been described and consisted of reproductive loss in breeding herds and acute respiratory disease in piglets. It was first isolated in Europe in 1991 (Lelystad virus, currently PRRSV-1) and in North America in 1992 (VR-2332, PRRSV-2). PRRSV is classified under genus Betaarterivirus in the family Arteriviridae and is noted for extreme genetic plasticity. During the last three decades, incessant mutation and recombination have generated variants that are heterogeneous in their pathogenicity and antigenic characteristics. The genetic variability has helped in disseminating PRRSV across the globe, making it one of the most influential pathogens impacting global swine production. PRRSV inflicts huge economic losses on the swine business in all major pig-producing regions. In breeding herds, the virus induces reproductive disease that is typified by abortions, stillbirths, and weak-born pigs. In growing and finishing pigs, the virus induces respiratory disease, secondary infections, and death (Nathues et al., 2017). All these clinical impacts combined result in decreased production efficiency, elevated treatment and biosecurity costs, and extended herd instability. Global economic analyses estimate losses of several billion U.S. dollars annually. That PRRSV becomes chronic in herds, along with recurrent reinfections, also makes eradication and control more difficult and thus it remains a persistent issue for veterinarians and producers (Zhang et al., 2024) PRRSV remains one of the most challenging and complex pathogens of veterinary virology. The virus has a high mutation and recombination rate, facilitating quick adaptation and immune evasion. Current vaccines are poor at
RkJQdWJsaXNoZXIy MjQ4ODYzNA==