Background: Transmission of HIV drug resistance (TDR) gives rise to reduced efficacy of initial antiretroviral treatment and has become a public health concern.
Methods: A nationwide survey on TDR was conducted in antiretroviral therapy-naive HIV-1-infected individuals from September 2004 to October 2005 in China. Drug resistance genotyping was performed on subjects' plasma samples. Drug resistance mutations were determined and scored by Stanford HIV Drug Resistance algorithm.
Results: Sequences were obtained from 676 individuals, of whom 61.2% were former plasma and blood donors, 17.3% were infected sexually, and 17.2% were intravenous drug users. Subtype B' HIV-1 strains were found in 73.5%, CRF01_AE in 13.9%, CRF07_BC in 6.2%, CRF08_BC in 2.7%, subtype C in 1.04%, subtype B in 0.9%, CRF02_AG in 0.4%, and B'/C intersubtype recombinant strains in 1.3% of the subjects. Twenty-six (3.8%) were found to harbor drug resistance strains. The rates of resistance to protease inhibitors, nucleoside reverse transcriptase inhibitors, and nonnucleoside reverse transcriptase inhibitors were 0.4%, 1.6%, and 2.1%, respectively. Though there was no significant difference in TDR rates between 2004 and 2005 (2.9% vs. 4.4%), an increased trend was observed in the rate of high-level drug resistance (0.8% in 2004 vs. 3.0% in 2005, P = 0.0634).
Conclusions: The rate of TDR was relatively low in China, as compared with those in developed countries. Surveys among recently HIV-infected subjects should be performed continually to ensure the success of the scale-up antiretroviral treatment.