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Published on: August 31, 2014
Multiple CRF01_AE/CRF07_BC Recombinants Enhanced the HIV-1 Epidemic Complexity Among MSM in Shenyang City, Northeast
Shan He1,2,3, Wei Song4, Gang Guo5
1NHC Key Laboratory of AIDS Immunology (China Medical University), National Clinical Research Center for Laboratory Medicine, The First Affiliated Hospital of China Medical University, Shenyang, China.
Abstract:
The transmission of Unique Recombinant Forms (URFs) has complicated the molecular epidemic of HIV-1. This increasing genetic diversity has implications for prevention surveillance, diagnosis, and vaccine design. In this study, we characterized the HIV-1 URFs from 135 newly diagnosed HIV-1 infected cases between 2016 and 2020 in Shenyang, northeast China and analyzed the evolutionary relationship of them by phylogenetic and recombination approaches. Among 135 URFs, we found that the CRF01_AE/CRF07_BC recombinants were the most common (81.5%, 110/135), followed by CRF01_AE/B (11.9%, 16/135), B/C (3.7%, 5/135), and others (3.0%, 4/135). 94.8% (128/135) of patients infected by URFs were through homosexual contact. Among 110 URFs_0107, 60 (54.5%) formed 11 subclusters (branch support value = 1) and shared the consistent recombination structure, respectively. Four subclusters have caused small-scale spread among different high-risk populations. Although the recombination structures of URFs_0107 are various, the hotspots of recombinants gathered between position 2,508 and 2,627 (relative to the HXB2 position). Moreover, the CRF07_BC and CRF01AE fragments of URFs_0107 were mainly derived from the MSM population. In brief, our results reveal the complex recombinant modes and the high transmission risk of URFs_0107, which calls for more attention on the new URFs_0107 monitoring and strict control in the areas led by homosexual transmission route.
Insights
Unique Recombinant Forms (URFs) of HIV-1 are complicating the epidemic. This study found CRF01_AE/CRF07_BC recombinants are most common in Shenyang, China, primarily transmitted through homosexual contact, highlighting urgent surveillance needs.
Area of Science:
- Virology
- Molecular Epidemiology
- Public Health
Background:
- The increasing genetic diversity of Human Immunodeficiency Virus type 1 (HIV-1) due to Unique Recombinant Forms (URFs) poses challenges for effective prevention, diagnosis, and vaccine development.
- Understanding the molecular epidemiology of HIV-1 URFs is crucial for controlling the epidemic, especially in regions with high transmission rates.
Purpose of the Study:
- To characterize the genetic diversity and evolutionary relationships of HIV-1 URFs in Shenyang, northeast China.
- To identify the predominant URFs and their transmission routes, with a focus on homosexual transmission.
- To analyze the recombination patterns and potential hotspots within common URFs.
Main Methods:
- Phylogenetic and recombination analyses were performed on HIV-1 URFs from 135 newly diagnosed cases between 2016 and 2020.
- Viral sequences were analyzed to determine the types of URFs, their prevalence, and their evolutionary relationships.
- Recombination breakpoint mapping was used to identify potential hotspots within the viral genome.
Main Results:
- CRF01_AE/CRF07_BC recombinants were the most prevalent (81.5%), followed by CRF01_AE/B (11.9%) and B/C (3.7%).
- Homosexual contact was the predominant transmission route, accounting for 94.8% of URF infections.
- Eleven subclusters of CRF01_AE/CRF07_BC recombinants were identified, with four showing small-scale spread, and recombination hotspots were located between positions 2,508 and 2,627.
Conclusions:
- The study highlights the complex recombinant modes and high transmission risk of HIV-1 URFs, particularly CRF01_AE/CRF07_BC, in Shenyang.
- The findings underscore the need for enhanced monitoring of novel URFs and stringent control measures, especially targeting the homosexual transmission route.
- Continued molecular surveillance is essential to track the evolution and spread of HIV-1 URFs and inform public health interventions.
