Porcine Enteric Coronaviruses: Origins, Global Spread, Transmission Pathways and Pathogenesis.

Porcine enteric coronaviruses (CoVs) constitute a persistent and evolving threat to global pig production due to their high transmissibility, environmental stability and capacity for rapid international dissemination. Historically, transmissible gastroenteritis virus (TGEV) and porcine epidemic diarrhoea virus (PEDV) have been the most significant enteric CoVs in swine, causing acute outbreaks with severe diarrhoea and high neonatal mortality. In the past decade, additional pathogens have expanded this epidemiological landscape of porcine enteric CoVs. Swine enteric CoV (SeCoV), porcine deltacoronavirus (PDCoV), and swine acute diarrhoea syndrome CoV (SADS-CoV) illustrate the remarkable genetic plasticity, recombination capacity and interspecies transmission potential of this viral group. To address these challenges, this review provides a comprehensive synthesis of the main scope regarding the origins, global spread, transmission pathways, and pathogenesis of these viruses. We emphasise the critical differences among them, particularly concerning transboundary dissemination, host range, and zoonotic potential. In conclusion, the repeated emergence and host adaptation of these agents underscore the urgent need to address surveillance gaps through continuous molecular tracking, improved biosecurity protocols, and the development of coordinated global control strategies to mitigate their impact on animal health and modern production systems.