Swine enteric coronaviruses (SECoVs), including transmissible gastroenteritis virus (TGEV), porcine epidemic diarrhea virus (PEDV), porcine deltacoronavirus (PDCoV), and swine acute diarrhea syndrome coronavirus (SADS-CoV), are major enteric pathogens causing severe diarrhea, dehydration, high neonatal mortality, and substantial global economic losses. Rapid viral evolution and recombination continually generate antigenically diverse variants that limit cross-protection and undermine vaccine efficacy, particularly for PEDV genogroup II strains that now dominate worldwide circulation. This review synthesizes current knowledge on epidemiology, diagnostic innovations, and emerging vaccine platforms, with emphasis on advances since 2022. Recent progress includes molecular surveillance tools, rapid point-of-care diagnostics, and next-generation vaccine technologies such as mRNA-based and virus-like particle platforms. However, significant knowledge gaps persist regarding viral evolution dynamics, co-infection synergies, and zoonotic spillover potential, particularly following documented human infections with PDCoV. Effective long-term control requires integrated genomic surveillance, strengthened farm-level biosecurity, rationally designed multivalent vaccines targeting conserved epitopes, and harmonized international surveillance systems to reduce outbreak risk and enhance pandemic preparedness at the human–animal interface.

Glycoprotein non-metastatic melanoma protein B (GPNMB) is a transmembrane protein enriched on the surface of some cells, including melanoma, glioblastoma, and macrophages. GPNMB has been reported to have multifaceted roles, such as facilitating cell–cell adhesion and migration, stimulating kinase signaling, and regulating inflammation. Porcine reproductive and respiratory syndrome virus (PRRSV) is the leading cause of severe economic loss in the swine industry worldwide. In this study, the role of GPNMB was investigated in porcine alveolar macrophages during PRRSV infection. We observed that GPNMB expression was markedly reduced in PRRSV-infected cells. The inhibition of GPNMB by specific small interfering RNA led to an enhancement in virus yields, and GPNMB overexpression decreased PRRSV replication. Further studies revealed that the overexpression of GPNMB could induce the accumulation of autophagosome through inhibiting autophagosome-lysosome fusion. Using a specific inhibitor, we confirmed that the inhibition of autophagosome-lysosome fusion significantly inhibited viral replication. Taken together, our data demonstrate that GPNMB inhibits PRRSV replication by inhibiting the autophagosome-lysosome fusion and provides a novel therapeutic target for virus infection.

Porcine reproductive and respiratory syndrome virus (PRRSV), a member of the Arteriviridae family, represents a persistent menace to the global pig industry, causing reproductive failure and respiratory disease in pigs. In this study, we delved into the role of histone deacetylases (HDAC2) during PRRSV infection. Our findings revealed that HDAC2 expression is downregulated upon PRRSV infection. Notably, suppressing HDAC2 activity through specific small interfering RNA led to an increase in virus production, whereas overexpressing HDAC2 effectively inhibited PRRSV replication by boosting the expression of IFN-regulated antiviral molecules. Furthermore, we identified the virus’s nonstructural protein 11 (nsp11) as a key player in reducing HDAC2 levels. Mutagenic analyses of PRRSV nsp11 revealed that its antagonistic effect on the antiviral activity of HDAC2 is dependent on its endonuclease activity. In summary, our research uncovered a novel immune evasion mechanism employed by PRRSV, providing crucial insights into the pathogenesis of this virus and guiding the development of innovative prevention strategies against PRRSV infection.

Paraoxonase-1 (PON1), an esterase with specifically paraoxonase activity, has been proven to be involved in inflammation and infection. Porcine reproductive and respiratory syndrome virus (PRRSV) is still a major concern in pigs and causes severe economic losses to the swine industry worldwide. In this study, the role of PON1 was investigated in porcine alveolar macrophages (PAMs) during PRRSV infection. The results showed that PRRSV replication downregulated PON1, and the knockdown of PON1 significantly decreased PRRSV replication. Similarly, PON1 overexpression could enhance PRRSV replication. Interestingly, we observed that PON1 interacted with PRRSV nonstructural protein 9 (Nsp9), the RNA-dependent RNA polymerase, and the knockdown of PON1 lowered the RNA binding ability of Nsp9, suggesting that PON1 can facilitate Nsp9 function in viral replication. In addition, the knockdown of PON1 expression led to the amplification of type I interferon (IFN) genes and vice versa. In summary, our data demonstrate that PON1 facilitates PRRSV replication by interacting with Nsp9 and inhibiting the type I IFN signaling pathway. Hence, PON1 may be an additional component of the anti-PRRSV defenses.

Porcine epidemic diarrhea (PED) continues to inflict devastating losses on global swine production. By systematically reviewing and meta-analysing 32 high-quality studies, we quantified the protective efficacy of PED vaccines and dissected how core variables shape that protection. Using fecal scores as the endpoint, we pooled effect sizes under a random-effects model and explored sources of heterogeneity through subgroup analyses. This analysis showed a pooled effect size (Hedges’ g) of −5.80, confirming that vaccination markedly alleviates diarrheal severity. Moreover, substantial heterogeneity was detected across studies. Stratified analyses revealed that vaccine type, vaccination target, vaccination route, and vaccination frequency are the principal sources of variation, all of which significantly influence vaccine efficacy. Conventional inactivated or live-attenuated formulations still dominate the field, but recombinant live-viral platforms are emerging. Piglets and sows represent the most responsive immunological targets. A two-dose regimen consistently outperforms a single injection, and delivery via intranasal, oral or intramuscular routes offers distinct advantages that can be exploited to maximise mucosal and systemic immunity. Overall, the optimal impact on PED prevention and control is achieved when the vaccine is correctly chosen and paired with an appropriate immunization protocol and delivery route.