Genetic characteristics and drug resistance of HIV strains isolated in Taiyuan, Shanxi, 2016–2017

ObjectiveTo understand the distribution of virus subtypes and the spread of drug-resistance of HIV isolated from untreated people living with HIV/AIDS (PLWHA) in Taiyuan, Shanxi province during 2016–2017.

MethodsA survey was conducted in newly reported and untreated PLWHA in Taiyuan from August 2016 to December 2017. Blood samples were taken from them for the extraction of HIV nucleic acid RNA, the pol region sequences were obtained, and a phylogenetic tree was constructed for HIV subtype determination. Drug resistance was analyzed by using the Stanford University HIVdb Program library, and HIV-1 molecular network analysis was performed with software HyPhy 2.2.4 and software Cytoscape 3.6.1.

ResultsA total of 227 pol region sequences were obtained from 251 newly reported and untreated PLWHA in Taiyuan. The study found that HIV-1 strains isolated in Taiyuan were predominated by subtype CRF01_AE, accounting for 52.0% (118/227), followed by CRF07_BC (32.6%, 74/227). The drug resistance rate of HIV-1 in the newly reported and untreated PLWHA was 5.3% (12/227), the resistance rate to non-nucleoside reverse transcriptase inhibitor (NNRTI) was 5.3% (12/227), and the resistance rate to nucleoside reverse transcriptase inhibitor (NRTI) was 1.3% (3/227), no protease inhibitor (PI) resistance was found. The molecular network access rate was 40.1% (91/227) according to the 1.5% gene distance threshold, and 12 clusters were found. The molecular network access rate was high in PLWHA infected with subtype CRF79_0107 (P＝0.01).

ConclusionMore than 80% of HIV-1 strains detected in Taiyuan belonged to subtype CRF01_AE and CRF07_BC, and the drug resistance rate to NNRTI was over 5%. The clustering transmission of infection of CRF79_0107 has been formed, so the investigation and intervention of this population need to be strengthened.