OBJECTIVETo understand the prevalence and evolution of HIV drug-resistant strains in people who live with HIV/AIDS (PLWHA) during HIV antiretroviral therapy in Shandong province.

METHODSViral load testing was performed by using fluorescence real-time quantitative PCR (NucliSens EasyQ system) on 324 patients who were under HIV antiretroviral therapy (ART) over 1 year in Shandong province. HIV resistance testing was conducted on the samples with more than 1000 copies/ml by using genotypic resistance testing method established in our lab. We tested the samples from drug-resistant patients before and after treatment to analyze the evolution of HIV resistant strains.

RESULTSThe resistance rate for the patients under HIV ART over 1 year was 6.2% (20/324). The rate of drug-resistant mutation, but not resistant to ART was 0.6% (5/324). Nucleoside reverse transcriptase inhibitor (NRTIs) and non-NRTIs (NNRTIs) accounted for 93.1% (94/101) and protein inhibitors (PIs) accounted only 6.9% (7/101) of all mutations. M184V (48.0%, 12/25) and Y181C (32.0%, 8/25) were the most frequent mutations among 25 samples. Our research showed 20.0% (2/10) patients were resistant to primary ART and 1 patient was detected drug resistance in 6 months after ART treatment. HIV evolved from wild type to drug resistant virus, from low level to high level drug resistance, and from resistance to few to multiple drugs. In addition, interactions between mutations may influence the sensitivity of patients to other drug treatment.

CONCLUSIONThe prevalence of HIV drug-resistant strains in Shandong province is still at a low level, but its evolution is complex.