Emergence of newly reported HIV-1 recombinants CRF120_0107 and CRF149_01B in Guangxi Zhuang Autonomous Region, China: Molecular evidence and public health challenges.

The Guangxi Zhuang Autonomous Region (Guangxi), located at the junction of Southwestern and Southern China, is a region with a high prevalence of human immunodeficiency virus type 1 (HIV-1). Understanding the genomic features and transmission dynamics of circulating HIV-1 strains is crucial for effective epidemic control. This study aimed to analyze the near-full-length genomic (NFLG) characteristics, recombination patterns, and cross-provincial transmission relationships of the newly reported recombinants CRF120_0107 and CRF149_01B in Guangxi. We selected six near-full-length HIV-1 genomic sequences (8,483-8,732 bp) from the entire study containing 508 samples collected from 2019 to 2024 in Nanning and Baise, Guangxi. Phylogenetic analysis revealed that samples GX.NN55.HET.2024, GX.NN152.MSM.2019, and GX.NN130.HET.2024 clustered into the same branch as the CRF120_0107 strain reported in Guangdong Province in October 2022. Recombination breakpoint analysis showed that CRF120_0107 was formed by recombination between CRF07_BC and CRF01_AE. Samples GX.BS401.HET.2024, GX.NN59.HET.2024, and GX.NN118.HET.2024 were highly homologous to the CRF149_01B strain reported in Yunnan Province in April 2025, which was recombined from CRF55_01B and subtype B. Sub-region phylogenetic analysis further confirmed that each fragment clustered with the corresponding subtype reference strain (bootstrap values > 90%). The first identification of CRF120_0107 and CRF149_01B strains in the Guangxi region based on six sequences suggests cross-provincial transmission of HIV-1 recombinant strains, highlighting the importance of molecular surveillance and targeted interventions to control viral spread.