HIV-1 genetic diversity and pretreatment drug resistance in Xishuangbanna, a China-Myanmar-Laos border region

China’s HIV-1 epidemic originated in the border regions of Yunnan Province in the late 1980s. Although domestic transmission has been effectively contained in recent years, the border regions continue to face public health challenges. In order to track the dynamic transmission of HIV-1, a molecular epidemiology study was conducted in a China-Myanmar-Laos border area. Between 2022 and 2023, 570 individuals newly diagnosed with HIV/AIDS were recruited in Xishuangbanna prefecture. The viral gene sequences were obtained through amplification and sequencing. The characteristics of the HIV-1 genotype distribution, genetic drug resistance and molecular networks were analyzed to identify relevant influencing factors. Of 486 samples that were genotyped, 16 different HIV-1 genotypes were identified. The predominant strains were CRF08BC (41. 5%), CRF01AE (20. 1%), CRF07BC (16. 6%) and unique recombinant forms (URFs, 13. 1%). The main HIV-1 genotypes exhibited specific associations with demographic factors, including registered residence, age, education level, infection status and reported area. The analysis of the dynamic molecular network revealed that local registered residence and age groups of 29 years and under and 50–59 years, were linked to network expansion. The overall prevalence of sequences carrying drug resistance-associated mutations (DRMs) was 39. 1% (195/499). HIV-1 genotypes were significantly associated with the distribution of DRMs. High-frequency resistance mutations exhibited genotype-specific distributions: V179D/VD and V179E of NNRTIs were significantly associated with CRF08BC and “other” genotypes, respectively; S68G/SG of NRTIs was significantly associated with CRF01AE. Drug-resistant strains were most prevalent among divorced/widowed individuals (OR = 1. 799, 95% CI: 1. 025–3. 157) and in those infected with CRF08BC (OR = 2. 981, 95% CI: 1. 434–6. 194). URFs were found to have a significantly higher risk of resistance to PIs (OR = 12. 649, P = 0. 002), while CRF08BC was found to have a higher risk of resistance to NNRTIs (OR = 4. 138, P = 0. 004). This study revealed the genetic diversity of HIV-1 and increasing drug resistance, as well as the transmission dynamics, in a high-risk transnational border region. The findings emphasized the importance of HIV-1 molecular surveillance in exploring high-risk populations and developing public health strategies to reduce HIV-1 transmission and control drug resistance in this area.