Genetic evolution and epidemiological dynamics of porcine epidemic diarrhea virus in Guangxi, China, from 2020 to 2023.

Porcine epidemic diarrhea virus (PEDV) remains a major threat to the global swine industry, leading to severe economic losses due to high mortality and morbidity in piglets. Although significant advances have been made in understanding its genetic features, comprehensive studies on the genetic evolution and epidemiology of PEDV remain limited. In this study, we analyzed PEDV N gene sequences obtained from Guangxi during the period of 2020 to 2023, alongside co-infection patterns involving other enteric viruses, including Porcine Rotavirus (PoRV) and Transmissible Gastroenteritis Virus (TGEV). A total of 559 clinical samples were collected from pig farms, followed by RT-PCR testing and sequencing of the PEDV N gene. Phylogenetic, Bayesian, and spatial analyses were employed to investigate the evolutionary dynamics and transmission patterns of PEDV strains. The results revealed a high PEDV positivity rate of 42.75%, with co-infection primarily involving PEDV and PoRV. Notably, novel 27 bp deletions in the N gene were identified, providing new insights into the virus's temporal and spatial evolution. The analysis also revealed key transmission hubs across multiple regions of China. Collectively, these findings enhance our understanding of PEDV's genetic diversity and epidemiology, offering valuable insights for future vaccine development and control strategies.