{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T03:52:15Z","timestamp":1791604335542,"version":"4.3.4"},"reference-count":45,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T00:00:00Z","timestamp":1788134400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T00:00:00Z","timestamp":1788134400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key Research and Development Program of China","award":["2023YFD1301900"],"award-info":[{"award-number":["2023YFD1301900"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Since NADC30-like PRRSV-2 was first detected in Henan Province in 2012, it has continued to spread and has become one of the predominant PRRSV-2 groups in mainland China. However, the long-term spatiotemporal dynamics, interprovincial transmission patterns, transmission drivers and recombination associated evolutionary features of sublineage L1C (L1C; NADC30-like) remain incompletely resolved. Here, we analysed 9541 quality-controlled lineage 1 ORF5 sequences from 12 countries, including ORF5 sequences from 62 laboratory-derived complete genomes assigned to L1C. Globally, 3787 sequences were classified as L1C. Among the 1648 lineage 1 sequences from China, 1362 were assigned to L1C, accounting for 82.65% of Chinese lineage 1 sequences. Phylodynamic analysis dated the global common ancestor of L1C to around 2002 and suggested that strains circulating in mainland China were likely introduced from US-related strains around 2008. Before the African swine fever (ASF) outbreak, inferred interprovincial transmission links were concentrated in a limited number of key provinces. During the early ASF period, observable links decreased, but they subsequently recovered and expanded across more provinces. Transmission-driver analysis suggested that pig inventory and pig output were associated with stronger inferred interprovincial L1C transmission links, whereas geographic distance was associated with a spatial-decay effect. Whole-genome recombination analysis revealed extensive recombination signals in L1C genomes involving other PRRSV-2 lineages. Among inter-lineage associations, L8E (HP-PRRSV\/JXA1-like) was the most frequently implicated background, followed by L5 and L3. These findings provide systematic evidence for the persistent prevalence, regional transmission and recombination-driven evolution of L1C in mainland China, and support molecular surveillance, regional risk warning and optimization of PRRSV-2 control strategies.<\/jats:p>","DOI":"10.3390\/v18090952","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T12:41:18Z","timestamp":1788266478000},"page":"952","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Molecular Epidemiology, Phylogeography, and Recombination Dynamics of PRRSV-2 Sublineage L1C in Mainland China"],"prefix":"10.3390","volume":"18","author":[{"given":"Jiyu","family":"Zhang","sequence":"first","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Weisheng","family":"Wu","sequence":"additional","affiliation":[{"name":"Shenzhen Kingkey Smart Agriculture Times Co., Ltd., Shenzhen 518001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zixuan","family":"Wang","sequence":"additional","affiliation":[{"name":"Shenzhen Kingkey Smart Agriculture Times Co., Ltd., Shenzhen 518001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lijun","family":"Wang","sequence":"additional","affiliation":[{"name":"Shenzhen Kingkey Smart Agriculture Times Co., Ltd., Shenzhen 518001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mengjuan","family":"Yang","sequence":"additional","affiliation":[{"name":"Shenzhen Kingkey Smart Agriculture Times Co., Ltd., Shenzhen 518001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guihong","family":"Zhang","sequence":"additional","affiliation":[{"name":"Shenzhen Kingkey Smart Agriculture Times Co., Ltd., Shenzhen 518001, China"},{"name":"Guangdong Provincial Key Laboratory of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shaoqin","family":"Wu","sequence":"additional","affiliation":[{"name":"Shenzhen Kingkey Smart Agriculture Times Co., Ltd., Shenzhen 518001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"236","DOI":"10.1007\/s00705-024-06143-y","article-title":"Changes to virus taxonomy and the ICTV Statutes ratified by the International Committee on Taxonomy of Viruses (2024)","volume":"169","author":"Simmonds","year":"2024","journal-title":"Arch. 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