[Molecular characteristics of HIV-1 CRF01_AE strains in Zhejiang province in 2009].

OBJECTIVE: To analyze the molecular epidemiological characteristics of HIV-1 subtype CRF01_AE strains being prevailed among HIV/AIDS in Zhejiang province in 2009. METHODS: A total of 303 subjects were identified by stratified random sampling among HIV infected individuals in Zhejiang province in 2009. Gag fragments of the HIV-1 strains were amplified by nested polymerase chain reaction from the DNA extracted from whole blood of HIV-1 infected individuals. PCR products were sequenced and analyzed by phylogenetic method. RESULTS: A total of 132 HIV-1 subtype CRF01_AE sequences were identified from the 225 samples that sequenced successfully, accounting for 58.67% (132/225). A total of 90.91% (120/132) CRF01_AE strains infected HIV/AIDS were transmitted mainly by sexual contacts. A total of 65.91% (87/132) of the cases infected by heterosexual route and 25.00% (33/132) by homosexual route. There were three main clusters in the phylogenetic tree. Pairwise DNA distance within three groups was 0.037 ± 0.011, 0.034 ± 0.008 and 0.047 ± 0.010, which has statistical significance (P < 0.05). Distribution of the sequence of homosexual behavior infected individuals was relatively concentrated in clusters one (96.97%, 32/33), and crossed with heterosexual behavior infectors, and presented the close relations with strains from Jiangsu province, Zhengzhou of Henan province, Liaoning province, Shijiazhuang of Hebei province. CONCLUSION: The CRF01_AE strains were the dominant subtypes among HIV infected individuals. The majority of the CRF01_AE infected cases had high risk sexual behavior. The heterosexual infected cases were more than homosexual cases. The circulating status of CRF01_AE strains in homosexual population was relatively independent, but also had evidence of transmission from man who have sex with man to heterosexual population.

[Survey of HIV drug resistance threshold in Zhejiang province from 2009 to 2011].

OBJECTIVE: To survey the prevalence of drug resistant HIV in Zhejiang province in 2009-2011. METHODS: WHO truncated sequential sampling technique was adopted annually by using 63, 62 and 57 samples of newly diagnosed as HIV positive and aged 16-25 years in Hangzhou, Ningbo and Wenzhou from 2009 to 2011, respectively. RNA was prepared and HIV pol region was amplified by RT-PCR and nested PCR. Pol genetic mutation associated with drug resistance was analyzed. RESULTS: The success rates for sequence acquisition of the survey were 82.5% (52/63), 95.2% (59/62) and 94.7% (54/57) from year 2009 to 2011, respectively, and the main subtype was CRF01_AE (68.5% (37/54)-71.2% (37/52)). A total of 4 surveillance drug-resistance mutation (SDRMs), 2 SDRMs and 2 SDRMs were found by analyzing the 47 sequences each year, sampled from year 2009 to 2010, respectively, indicating that the prevalence of drug resistant HIV stains was moderate in 2009, and low for the next two years (2010-2011). A total of 8 individuals with drug resistant HIV stains found in this study were all infected by sexual transmission, especially in homosexual transmission (6 cases), and the main subtype was CRF01_AE (7 cases). SDRMs for protease inhibitor (PI), nucleotide HIV-reverse transcriptase inhibitor (NRTI) and non-NRTI (NNRTI) (L90M, T215S and Y188L) were all found in one case. CONCLUSION: The prevalence of drug resistant HIV stains in major areas with AIDS epidemic in Zhejiang province was low in 2009-2011.

[Analysis of epidemiological characteristics of HIV infections among immigrant marriage women in rural areas in Zhejiang province].

OBJECTIVE: To analyze the epidemiological characteristics of HIV infected immigrant marriage women in rural areas in Zhejiang province. METHODS: A retrospective investigation was conducted among 118 HIV infected immigrant marriage women, who were detected in active or passive surveillance in rural areas in Zhejiang province. The investigation information included the basic demographic characteristics, risky behavior, the status of HIV infection among their spouses and children. EpiData 3.0 and SPSS 13.0 software were used for database set up and bivariate and multiple logistic regression analysis. RESULTS: By the end of 2009, a total of 118 HIV/AIDS were reported among immigrant marriage women. Of which, 53.4% (63/118) of the subjects were from Yunnan province and 33.1% (39/118) were minority nationality, and 30.6% (39/108) of their spouses were diagnosed HIV infection when these targeted women were detected. In discordant couples follow up with female partner being HIV positive, the spouse seroincidence rate was 2.09 per 100 person years (3/143.5 person years). Subjects who had sexual behavior beyond marriage accounted for 83.9% (99/118) of total, and 69.5% (82/118) subjects had former boyfriend or former husband in former inhabited places. In the 36 concordant-positive couples, 63.9% (23/36) reported never using condom in in-marriage sexual behavior before being detected HIV positive. Bivariate analysis results revealed that the significant difference for the HIV positive testing rate for a couple among different time duration that an immigrated woman moved to Zhejiang province due to marriage was observed (χ(2) = 8.708, P = 0.003). While the number and proportion of HIV positive couples for those immigrated women who lived in Zhejiang province for less than 2 years, 2 - 5 years, more than 5 years were 12 (20.7%), 9 (31.0%), 11 (57.9%), respectively. Multiple logistic regression analysis showed that the long time length when an immigrated woman was detected positivity after she moved to Zhejiang province was the risk predictor of their husband being infected (OR = 2.223; 95%CI: 1.288 - 3.836). CONCLUSION: It is showed that premarital unsafely sexual behavior, in-marriage sexual behavior without condom, delayed detection of HIV are risk factors for HIV infection and transmission.

[Relationship between strain subtypes and transmission of HIV infection within marriage-based immigrant women in rural area of Zhejiang province].

OBJECTIVE: To analyze the relationship between strain subtypes and transmission of HIV infection on marriage-based immigrant women, their spouses and children in rural area of Zhejiang province. METHODS: Marriage-based immigrant women with HIV infection, their HIV infected spouses and children in rural area in Zhejiang province, were selected as study objects. Analysis on genetic sequence and epidemiologic information was carried out. Subgenomic gag was amplified by nest-PCR analysis on the whole blood samples. Genetic subtype characterization and the source of HIV strains were analyzed. Relationships on sequences were also examined by phylogenetic tree analysis. RESULTS: Genetic sequences of 72 samples from HIV infected marriage-based immigrant women were obtained. The genetic subtypes comprised 21 CRF01_AE (29.2%), 12 CRF07_BC (16.7%), 31 CRF08_BC (43.1%), 6 B (8.3%), 2 C (2.8%). HIV strains from 45 cases (62.5%) were similar to the prevalent HIV strains in the province where former census of marriage-based immigrant women were registered. In total, there were 26 (70.3%) cases from Yunnan province. 84.7% of the infected women had heterosexual behaviors before settling down in Zhejiang province. Genetic sequences of 17 pairs showed the same subtype between the couples and data from phylogenetic tree analysis supported the assumption of transmission linkage in the family. CONCLUSION: The HIV subtype strains detected in those HIV infected marriage-based immigrant women in the rural area of Zhejiang province characterized with diversity, showing CRF08_BC and CRF01_AE were the main HIV strain subtypes. HIV infection originated mainly from Yunnan province and nearby regions. Heterosexual behaviors of the marriage-based immigrant women in the original region where they had their residence registration, seemed to be the primary high risk factors for these women. Surveillance and intervention programs on these marriage-based immigrant women and their family members should be improved.

[Subtype and transmission of HIV strain in both HIV infected spouses in Zhejiang province].

OBJECTIVE: To analyse the subtype and transmission of HIV strain in both HIV infected spouses. METHODS: Reported both HIV infected spouses were selected as objects. Analysis on genetic sequence and high risk behaviors was carried out. Subgenomic gag was amplified by nest-PCR analysis of whole blood samples from objects. Genetic subtype characterization of HIV was identified and pairwise genetic distances were calculated. Sequence relationships were also examined by phylogenetic tree analysis. RESULTS: Genetic sequences of 46 pairs (92 cases) were obtained. The genetic subtype comprised 39 CRF01_AE (42.4%), 10 CRF07_BC (10.9%), 18 CRF08_BC (19.6%), 18 B (19.6%), 5 C (5.4%) and 2 CRF02_AG (2.2%). 44 pairs had the same subtype between the two partners, accounted for 95.7% of the total. 33 of the 41 pairs with phylogenetic tree analysis were found having epidemiological linkage in pair wise. Sexual behaviors of out-marriage were the main risk factors of CRF01_AE and CRF08_BC and CRF02_AG strains infection. Blood transmission was associated with B and CRF07_BC. CONCLUSION: The HIV strains subtype detected in HIV infected spouses characterized with diversity. CRF01_AE was the main strain subtype. The main route of transmission to the spouses was through unprotected sexual contacts. Surveillance programs on HIV infected partner together with intervention between the spouses should be improved.

[Genotypic drug-resistance of HIV-1 CRF01_AE in Zhejiang province, 2004-2007].

OBJECTIVE: To study the genotypic drug-resistant mutation among treat-naïve or treated patients infected with HIV-1 CRF01_AE in Zhejiang province during 2004-2007. METHODS: HIV-1 pol amplicons (PR + RT) from 13 treated and 43 treat-naïve patients were obtained by reverse transcription-polymerase chain reaction (RT-PCR). The sequences were analyzed for genotypic antiretroviral resistance through online tools (http://hivdb.stanford.edu). RESULTS: The median count of CD4+ T lymphocytes in 43 treat-naïve patients was 229 cells /mm3 and the median log10 viral load was 3.41. Some drug-resistant mutations were seen in these samples including amino acid 10, 46, 71, in the genes ofprotease (PR) and 103, 118, in the genes of reverse transcriptase (RT) whereas twenty-nine resistance mutations in the genes of PR and RT were obtained in the 13 treated patients (8/13, 61.5%). The high prevalence of drug-resistant mutations was observed in patients who had been receiving HAART (hight active antiretroviral therapy). Among them, cross drug resistance was dominant. Correspondingly, the median counts of CD4+ T lymphocytes and the log10 viral load were 186 cells/mm3 and 3.91. CONCLUSION: There was a low prevalence of genotypic drug-resistant mutations in treat-naïve patients, but higher drug-resistant mutation in treated patients. More attention should be paid to the transmission of drug-resistant HIV strains and the antiretroviral therapy recipe should be adjusted correspondingly for the development of ART drugs, intervention as well as clinical therapy programs.

[Molecular characteristics of HIV-1 CRF01 _ AE strains in Zhejiang province].

OBJECTIVE: Using molecular epidemiology method to characterize human immunodeficiency virus type 1 (HIV-1) subtype CRF01 _ AE strains being prevailed in Zhejiang province. METHODS: Gag fragments of the HIV-1 strains were amplified by nested-polymerase chain reaction (nPCR) from the DNA extracted from whole blood of HIV-1 infected individuals in Zhejiang province. PCR products were sequenced and analyzed by phylogenetic method. RESULTS: 81 HIV-1 subtype CRF01 _ AE sequences were identified from the 192 samples that sequenced successfully. As one of the dominant subtypes in Zhejiang, CRF01 _ AE was transmitted mainly by heterosexual or homosexual contact in local residents. In migrants living in Zhejiang, CRF01 _ AE were transmitted mainly by heterosexual contact or injecting drug use. There were three main clusters in the phylogenetic tree which bootstrap value was larger than 60. We named the clusters with group MIX (47 sequences), group SEX (7 sequences) and group MSM (12 sequences) based on the transmission. Pairwise DNA distances in the gag region within the three groups and between CM240 were different (P = 0.000). Data through the analyses of deduced amino acid sequences from the three groups showed that several signature amino acid sites were distinct from the same positions of the subtype reference strains. CONCLUSION: The CRF01 _ AE strain prevailing in Zhejiang province was from several sources, transmitted by more than three different transmission routes, and becoming the main subtypes circulating in homosexual population in this study. More attention needs to be paid to the epidemic characteristic of CRF01 _ AE.