Emergence of newly reported HIV-1 recombinants CRF120₀107 and CRF149₀1B in Guangxi Zhuang Autonomous Region, China: Molecular evidence and public health challenges

• Scientific questions. • Human immunodeficiency virus type 1 (HIV-1) recombination plays a key role in the evolution and epidemic dynamics of the virus in China. The emergence of new recombinant forms may complicate diagnosis, treatment, and molecular monitoring. However, the genomic data available to track cross-provincial spread and public health impact are limited. • Evidence before this study. • Previous molecular epidemiological studies in southern and southwestern China have reported a variety of emerging HIV-1 recombinant strains, including CRF120₀107 and CRF149₀1B. These strains were mainly found in Guangdong and Yunnan Province, but information on their genetic characteristics, regional transmission, and potential establishment in neighboring Guangxi Zhuang Autonomous Region (Guangxi) remains unclear. • New findings. • We identified six near-full-length HIV-1 genomes from Guangxi. Three sequences from Nanning clustered with the CRF120₀107 strain reported in Guangdong, and three sequences from Baise and Nanning City clustered with the CRF149₀1B strain reported in Yunnan Province. Recombination breakpoints and sub regional analysis confirmed that these viruses had the same mosaic structure as their corresponding reference recombinant viruses, indicating that they had rapidly spread across provinces in Guangxi and were established locally. • Significance of the study • This study provides molecular evidence for the cross-provincial and local transmission of CRF120₀107 and CRF149₀1B in Guangxi. These findings emphasize the need to enhance genomic surveillance and cross-regional cooperation to prevent the further spread of recombinant HIV-1 strains. 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 CRF120₀107 and CRF149₀1B 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 CRF120₀107 strain reported in Guangdong Province in October 2022. Recombination breakpoint analysis showed that CRF120₀107 was formed by recombination between CRF07BC and CRF01AE. Samples GX. BS401. HET. 2024, GX. NN59. HET. 2024, and GX. NN118. HET. 2024 were highly homologous to the CRF149₀1B strain reported in Yunnan Province in April 2025, which was recombined from CRF55₀1B 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 CRF120₀107 and CRF149₀1B 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.