{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T06:28:14Z","timestamp":1787120894639,"version":"build-2736575974"},"reference-count":51,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T00:00:00Z","timestamp":1787097600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>The ageing population poses emerging challenges to HIV prevention, particularly in regions with high proportions of older adults. We conducted a cross-sectional study of 513 newly diagnosed HIV-infected individuals in Shaodong City, Hunan Province, China, between 2021 and 2025, with a focus on individuals aged \u226560\u202fyears.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>HIV-1 pol sequences were amplified, sequenced, and analyzed for subtype distribution and transmitted drug resistance (TDR). Molecular transmission networks were constructed using a 0.5% genetic distance threshold, and clusters were classified as large (\u226510 nodes), medium (5\u20139 nodes), or small (&amp;lt;5 nodes).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>CRF85_BC was the predominant subtype (32.55%), and a total of 37 transmission clusters were identified, with the two largest clusters comprising 99 and 19 nodes, respectively. High-risk nodes, defined as those with a transmission network score (TNS)\u202f\u2265\u202f0.75 and degree \u22654, were primarily older male farmers engaged in heterosexual commercial sex. The overall TDR prevalence was 10.53%, with NNRTI resistance predominating, and K103N being the most frequent mutation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Our findings indicate that HIV transmission among older adults exhibits substantial clustering, largely driven by commercial sexual activity, and highlight the importance of molecular network analysis for identifying high-risk individuals and guiding targeted prevention interventions. Continuous surveillance of TDR within active clusters is critical for optimizing antiretroviral therapy strategies and mitigating onward transmission.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fmicb.2026.1876738","type":"journal-article","created":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T05:49:04Z","timestamp":1787118544000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Molecular transmission network analysis of HIV-1 among older adults in Central China: a cross-sectional study in Shaodong City"],"prefix":"10.3389","volume":"17","author":[{"given":"Xiaobai","family":"Zou","sequence":"first","affiliation":[{"name":"Hunan Provincial Center for Disease Control and Prevention","place":["Changsha, Hunan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Liu","sequence":"additional","affiliation":[{"name":"Hunan Provincial Center for Disease Control and Prevention","place":["Changsha, Hunan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jieyu","family":"Zhou","sequence":"additional","affiliation":[{"name":"Hunan Provincial Center for Disease Control and Prevention","place":["Changsha, Hunan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinghang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Hunan Provincial Center for Disease Control and Prevention","place":["Changsha, Hunan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Chen","sequence":"additional","affiliation":[{"name":"Hunan Provincial Center for Disease Control and Prevention","place":["Changsha, Hunan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jingxin","family":"Li","sequence":"additional","affiliation":[{"name":"Shaoyang Center for Disease Control and Prevention","place":["Shaodong, Hunan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenxiu","family":"Deng","sequence":"additional","affiliation":[{"name":"Shaodong Center for Disease Control and Prevention","place":["Shaoyang, Hunan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huan","family":"Chen","sequence":"additional","affiliation":[{"name":"Hunan Provincial Center for Disease Control and Prevention","place":["Changsha, Hunan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,19]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"137","DOI":"10.1093\/infdis\/jiae428","article-title":"Sustained spread of HIV-1 CRF55_01B in its place of origin: dynamics and hotspots","volume":"231","author":"An","year":"2025","journal-title":"J. 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