[Distribution of HIV-1 subtype and prevalence of HIV-1 drug resistance in Liuzhou and Nanning].

To investigate HIV-1 subtype distribution and prevalence of HIV-1 drug resistance in Liuzhou and Nanning, a total of 304 HIV-infected subjects or AIDS patients from Liuzhou and Nanning were recruited. Whole blood was withdrawn from a peripheral vein of each subject. HIV RNA were extracted from plasma, and subjected to PCR amplification targeting HIV pol gene fragment and DNA sequencing. Sequences obtained were subtyped by phylogenetic analysis. Two subtypes, CRF01_AE and CRF07_BC, were found in subjects from Liuzhou, accounting for 75.2% and 24.8%, respectively. Subtype CRF01 AE, CRFO8_BC, B, and C were found in subjects from Nanning. CRF01_AE and CRF08 BC were still the dominant strains in Nanning, accounting for 85.8% and 11.5%, respectively. Sequences were also analyzed for drug resistance mutations, and rates of drug resistance were calculated. The rate of drug resistance was 3.3% in ART-naive subjects from Liuzhou, and 8.7% in the ART-experienced. For patients from Nanning, the rate was 1.4% in ART-naive subjects, and 27.5% in ART-experienced subjects.

[A nested multiplex PCR assay for rapid subtyping the prevailing HIV-1 strains in Guangxi].

OBJECTIVE: To establish a rapid nested multiplex PCR assay for subtyping HIV-1 CRF01_AE, CRF07_BC, CRF08_BC, B, and C strains prevailing in Guangxi. METHOD: Subtype-specific primers were designed for these subtypes based on their gag sequences. The subtypes of HIV-1 samples from Guangxi were determined by nested multiplex PCR and DNA sequencing and phylogenetic analysis, respectively, and then the sensitivity and the specificity of nested multiplex PCR were calculated. RESULTS: Nested multiplex PCR could correctly classify the 5 known-subtype samples, and were not reactive to all HIV-negative samples. Of the 72 HIV-positive samples, 66 were correctly identified as CRF01_AE, CRF07_BC, CRF08_BC, and B by this assay, giving a sensitivity of 91.7% (66/72), and a specificity of 100%. CONCLUSION: This assay is a simple, fast, and cost-effective subtyping method for HIV-1 CRF01-AE, CRF07_BC, CRF08_BC, and B strains prevailing in Guangxi.