Comparative analysis on both high risk behaviours, infection of HIV and syphilis between married and unmarried men who have sex with men / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the distribution of marriage status among men who have sex with men (MSM) in the city of Changzhou, and to explore the impact of marriage on AIDS related high risk behaviors and HIV infection in this population.</p><p><b>METHODS</b>Target sampling (snowball sampling) was adopted to carry out a cross-sectional study, and structured questionnaire-based interviews were conducted to collect information on social demography, HIV related high risk behaviors. Blood and urine samples were collected to detect HIV, syphilis, gonorrhea and Chlamydia trachomatis infections.</p><p><b>RESULTS</b>Of the 655 participants, 37.4% were married. Married MSM mostly sought their sexual partners at the public bathing house (61.6%), while unmarried MSM were mainly through bars (33.6%) or internet (31.1%). The proportion of having anal sex with men during the last 6 months was lower in the married group (50.8%) than in the unmarried group (73.3%), (P < 0.001) The percentage of having sex with women in the last 6 months was significantly higher in the married group (68.9%) than that in the unmarried group (33.2%) (P < 0.001), (OR = 4.454, 95%CI: 3.168 - 6.261). The rates of condom use in the last anal sex with men in married and unmarried groups were 71.0% and 77.6%, respectively (P = 0.152). The rate of condom use in the last intercourse with women was significantly lower in the married group (44.0%) than that in the unmarried group (70.4%) (P < 0.001), (OR = 0.331, 95%CI: 0.205 - 0.535). In the sex trade, most of the married MSM would "buy" sex (66.7%), while unmarried MSM would "sell" sex (63.2%) (P < 0.05), (OR = 3.429, 95%CI: 1.255 - 9.366). The percentage of having drugs in the previous year was higher in married group (3.3%) than that in the unmarried group (0.8%) (P < 0.05). In married and unmarried groups, the infection rates of HIV, syphilis, gonorrhea and Chlamydia trachomatis appeared to be (8.6%, 8.6%), (17.1%, 12.3%), (1.6%, 2.4%), and (3.3%, 9.0%), respectively (P > 0.05).</p><p><b>CONCLUSION</b>Marriage seemed to have had limited effects on reducing the high risk behaviors of MSM. Different and multiform interventions should be developed according to the different characteristics of married or unmarried MSM population.</p>

Analysis on Mycoplasma pirum infection in male HIV/AIDS patients and related 16S rRNA genes in Jiangsu province / 中华流行病学杂志

Objective To investigate the prevalence ofMycoplasma pirum (Mpi) in male HIV infected patients,and to identify the 16S rRNA gene of Mpi.Methods The first void urine of male HIV/AIDS patients in Jiangsu province was collected for Mpi detection.Purified 16S rRNA gene PCR production was sequenced for analysis on its identification,homogeneity and phylogenetic tree.P1 protein sequence of Mpi was analyzed by Vector NTI Advance 11.0 to calculate the coded amino acid sequence.Homogeneity analysis was conducted between the theoretical amino acid sequence of Mpi and other Mycoplasmas.Results The prevalence of Mpi in male HIV/AIDS patients was 21.5％while the Mpi prevalence rates in different age groups were significantly different (x2Mpi=124.63,P＜0.01).The homogeneity of 18 strains of Mpi was higher than 90％.Conclusion The Mpi prevalence seemed much higher than the results from previous detection on HIV/AIDS patients,suggesting that more attention should be paid on AIDS treatment.More bioinformatic research on gene/nucleotide sequence analysis and forecast should be carried out to identify the molecular characteristics of Mpi.

The application of network scale-up method on female sex workers and clients size estimation in Taizhou city / 中华预防医学杂志

<p><b>OBJECTIVE</b>To estimate the size of female sex workers and clients in Taizhou city.</p><p><b>METHODS</b>A household survey using network scale-up method (NSUM) was conducted among the 3000 community residents in Taizhou city from August to October in 2011, which aimed to estimate the social network size (c value) of Taizhou residents, and the c value was adjusted by demographic characteristics, back estimation and outlier elimination. Using the adjusted c value, the number of acquaintance of female sex workers or clients and the respect level toward female sex workers or clients were used to estimate the size of female sex workers and clients.</p><p><b>RESULTS</b>A total of 2783 valid questionnaires were collected, among which 1380 (49.6%) were collected from Taixing city, 1403 (50.4%) were collected from Jingjiang city. 1334 respondents were male (47.9%) and 1449 (47.9%) respondents were female. The mean age was (39.4 ± 10.7) years. The average personal social network size using original data for Taizhou residents was 525, which differed from place, sex, age, educational level and marriage status. Using the remaining known populations through back estimation, the social network size was 419 and became 424 after the elimination of outliers. The estimated population size for female sex worker was 6370 (95%CI: 5886 - 6853), which accounted for 0.52% (6370/1 229 980) of the total number of female aged from 15 to 49. The estimated population size for clients was 15 202 (95%CI: 14 560 - 15 847), which accounted for 1.28% (15 202/1 190 340) of the total number of males aged from 15 to 49 and the ration of clients to female sex worker was 2.39:1.</p><p><b>CONCLUSION</b>NSUM is an easy and quick way to estimate the size of female sex workers or clients, but the estimated sizes are subject to bias and error due to estimate effect and sample representativeness.</p>

Study on the spatial distribution of AIDS based on geographic information system in Jiangsu province / 中华流行病学杂志

Objective To analyze the spatial distribution of AIDS in every city of Jiangsu province, trying to describe the geographic characteristics of AIDS and to develop a prediction model.Methods Numbers of patients in Jiangsu province were collected, to establish the database for the geographic information system, then setting up a 'risk map' of the disease. Spatial, autocorrelation.Linear spatial analyses were used to study the patients' numbers. Results (1)Results from the autocorrelation analysis showed that the distribution of AIDS was clustered at some places and was at random on the whole. The results also indicated that the distribution of AIDS in Nanjing was of negative correlation, while that in Suzhou and Wuxi were of positive correlation but in Tongshan, Wujiang, Pukou, Nanjing, Lishui, Wuxi and Suzhou showed seven locations of clusters with disease was more severe in the southern than in the northern parts of Jiangsu province. (3)Ordinary Least Squares method was finally used in the linear spatial regression and the results were: t=-1.045 103 (P=0.299 904); t=-1.443 668 (P=0.153 714) respectively. Conclusion According to the feature spatial distribution of the disease, effective measures should be taken to prevent and to keep the prevalence of AIDS under control.

Analysis on sexually transmitted diseases and the related risk factors among men who have sex with men in Jiangsu province / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate infections of syphilis, neisseria gonorrhoeae, chlamydia trachomatis and the related risk factors in men who have sex with men (MSM) in Jiangsu province.</p><p><b>METHODS</b>A total of 400 MSM were enrolled by Snowball Sampling Method from August to October in 2010 and then 328 cases were surveyed by a questionnaire and collected serum sample 5 ml per person as well as rectal swab on the spot; all of the serum samples were tested for syphilis by ELISA and TRUST, and all of the rectal swabs were tested for neisseria gonorrhoeae or chlamydia trachomatis. The influencing factors of syphilis, neisseria gonorrhoeae, chlamydia trachomatis were analyzed by logistic regression analysis.</p><p><b>RESULTS</b>The 328 MSM were (32.46 ± 9.72) years old, 59.15% (194/328) were unmarried.75.00% (246/328) MSM had rectal sex with men in the past 3 months, and condom use rate for recent sex was 56.71% (186/328), while 53.05% (174/328) MSM didn't have sex with women in the last 3 months. The syphilis infection rate among MSM was 13.41% (44/328), the neisseria gonorrhoeae infection rate was 3.66% (12/328), and the chlamydia trachomatis rate was 11.59% (38/328). The number of sex partners was the key factor that influenced syphilis infections (OR = 4.213, 95%CI: 1.133 - 15.656).</p><p><b>CONCLUSION</b>The prevalence of syphilis and chlamydia trachomatis was high in MSM in Jiangsu, while risk behavior rate were high in the MSM and then should be intervened.</p>

Estimation and prediction of the epidemic situation of acquired immunodeficiency syndrome in Jiangsu province / 中华预防医学杂志

<p><b>OBJECTIVE</b>The aim of this study was to estimate and predict the AIDS epidemic situation in Jiangsu province by using a software named Estimation and Projection Package (EPP) and then to provide accurate information for making control plans and conducting interventions.</p><p><b>METHODS</b>Date were obtained from the comprehensively monitored sentinels of AIDS and venereal diseases (Data were from 28 national monitored stations and 52 provincial stations. From 2003 to 2009, a total of 10 730 000 people had been monitored) as well as project survey and laboratory tests. EPP epidemic model was employed to analyze the prevalence and to predict future epidemic situations.</p><p><b>RESULTS</b>A total of 830 000 and 1 020 000 people were monitored in 2003 and 2004 respectively, and 8 880 000 more people were monitored in the following 5 years. By the end of 2009, a total of 4103 HIV infection cases had been reported, among which 918 people were diagnosed with AIDS and 432 died. Since 2003, the cases infected through IDU had decreased from 66.84% (262/392) to 16.40% (142/868). However, the cases infected through sex contact had increased from 21.68% (85/392) to 77.40% (672/868). Among these cases, homosexual transmission and heterosexual transmission accounted for 39.10% (339/868) and 38.30% (333/868) respectively. It was estimated that there would be 14 290 HIV/AIDS cases in 2011 which is 18.10% (2191/12 099) higher than that in 2009. The estimated HIV infection rate would be 0.02%.</p><p><b>CONCLUSION</b>EPP prediction showed the AIDS epidemic situation in Jiangsu province had an ascendant trend and the AIDS epidemic situation had demonstrated rapid growth. Therefore, it is necessary to take effective preventive measures to control the spread of AIDS.</p>

Factors associated with HIV infection among men who have sex with men in Nanjing, Suzhou and Yangzhou: a 1:4 matched case-control study / 中华流行病学杂志

Objective This study assessed the main factors associated with HIV infection among men having sex with men(MSM),in order to provide evidence for future intervention. Methods A case-control study was conducted among HIV cases identified at the MSM survey in Nanjing, Suzhou and Yangzhou cities from May to July in 2008. Each HIV case was matched by 4 HIV negative MSM who participated consecutively right after the HIV case was identified at the same survey, same time and in the same city. A national core MSM survey questionnaire was used with addition of variables of local interest. Fitting conditional logistic regression model was applied for univariate and multivariate analysis. Results During the survey, 62 HIV positive cases were identified and 248 controls were matched. Data from univariate analysis showed that, inconsistent condom use, syphilis infection, self reported sexually transmitted infection (STI) symptoms and/or signs, unprotected anal sex (UAI) were risk factors, with OR values of 5.56(95%CI: 1.82-16.96), 2.19(95%CI: 1.18-4.05), 2.50(95%(CI: 1.13-5.50) and 3.13 (95%CI: 1.64-5.98) respectively. Online cruising and receptive anal sex were protective factors with OR values as 0.47(95%CI: 0.22-0.998) and 0.67(95% CI: 0.23-1.97). Through multivariate analysis, it was found that syphilis, age of having experienced first insertive sexual intercourse and UAI were risk factors to HIV transmission, with OR values of 2.28 (95%CI: 1.05-4.94), 4.16 (95%CI: 1.63-10.66) and 1.11 (95% CI: 1.04-1.18) respectively. Compared with non-anal sex, bisexual (OR=0.41,95%CI: 0.18-0.97) behavior seemed a protected factor. Conclusion Syphilis infection, UAI and self reported STI symptoms and/or signs were risk factors related to HIV transmission while bisexual seemed a protective factor.