Abstract

We assessed HIV prevalence and associated behaviors and risk factors among men who have sex with men (MSM) in Beijing, China. Five hundred MSM were recruited for a biological and behavioral survey using respondent-driven sampling (RDS) in 2009. Serologic specimens were tested for markers of HIV and syphilis infection. A computer-assisted personal interview (CAPI) administered questionnaire gathered information including demographic characteristics, sexual behaviors, HIV testing, and social norms concerning condom use. The adjusted HIV prevalence was 8.0%, syphilis 22.0%. HIV testing and disclosure was low; only 39.3% had HIV tested in the past 12 months, 49.7% knew their own HIV status and 22.8% knew their last male partner's HIV status. HIV infection was associated with syphilis, ever having sex with a woman, not knowing the HIV status of the most recent male partner, and never buying condoms in the past 12 months. Stronger endorsement of positive social norms around condom use strongly and predicted lower prevalence of HIV infection. Compared to surveys of similar design in the recent past, HIV continues to spread rapidly among Beijing's MSM. Our results identify points of intervention that, if addressed in time, may still alter the course of the epidemic including the promotion of HIV testing and partner disclosure, syphilis control and particularly changing social norms around condom use.

Background

Highly active antiretroviral therapy (HAART) has significantly decreased mortality among Chinese HIV patients. However, emerging HIV drug resistance (HIVDR) poses a growing threat to the long-term success and durability of HAART.

Methods

Three cross-sectional surveys were conducted across the country from 2004 to 2006, respectively. Patients completed a questionnaire and provided blood for CD4 cell count, HIV viral load (VL), and HIV resistance genotyping. Factors associated with HIVDR were identified by logistic regression.

Results

3667 unique patients were included across the three surveys. Among 2826 treatment-experienced patients, median duration of treatment was 17.4 (IQR 8.6–28.4) months and HIVDR was identified in 543 (19.2%). Factors significantly associated with HIVDR included ART drug distribution location, CD4 cell count, initial HAART regimen, self-reported medication adherence, and province.

Conclusions

Virologic failure increased over time on therapy but a significant proportion of patients in failure had no resistance mutations identified, suggesting that treatment adherence is suboptimal and must be emphasized. Due to the significantly higher risk of HIVDR in certain provinces, additional steps to reduce HIVDR should be taken.

Objectives

(1) To assess the HIV incidence rate among men who have sex with men (MSM) in a large cohort study in Beijing, China and (2) to identify sociodemographic and behavioural risk factors of HIV seroconversion among MSM in Beijing, China.

Design

A prospective cohort study.

Setting

Baseline and follow-up visits were conducted among MSM in Beijing, China.

Participants

A cohort of 797 HIV-seronegative MSM was recruited from August to December 2009, with follow-up occurring after 6 and 12 months.

Primary and secondary outcome measures

At baseline and follow-up visits, participants reported sociodemographic and sexual behaviour information, and were tested for HIV, herpes simplex virus-2 (HSV-2) and syphilis with whole blood specimens. Cox regression analysis was used to identify factors associated with HIV seroconversion.

Results

Most study participants (86.8%) were retained by the 12-month follow-up. The HIV, HSV-2 and syphilis incidence rates were 8.09 (95% CI 6.92 to 9.26), 5.92 (95% CI 5.44 to 6.40) and 8.06 (95% CI 7.56 to 8.56) cases per 100 person-years, respectively. HIV seroconversion was significantly associated with being <25 years old, having <12 years of education, having >1 male sex partner in the past 6 months, and being syphilis positive or HSV-2 positive.

Conclusions

The HIV incidence among MSM in Beijing is serious. Interventions and treatment of sexually transmitted diseases (STD) should be combined with HIV control and prevention measures among MSM.

Background

China is experiencing a dynamic HIV/AIDS epidemic. While serology based surveillance systems have reported the spread of HIV/AIDS, detailed tracking of its transmission in populations and regions is not possible without mapping it at the molecular level. We therefore conducted a nationwide molecular epidemiology survey across the country.

Methods

HIV-1 genotypes were determined from 1,408 HIV-positive persons newly diagnosed in 2006. The prevalence of each genotype was estimated by weighting the genotype’s prevalence from each province- and risk-specific subpopulation with the number of reported cases in the corresponding subgroups in that year.

Results

CRF07_BC (35.5%), CRF01_AE (27.6%), CRF08_BC (20.1%), and subtype B' (9.6%) were the four main HIV-1 strains in China. CRF07_BC and CRF08_BC were the primary drivers of infection among injecting drug users in northeastern and southeastern China, respectively, and subtype B' remained dominant among former plasma donors in central China. In contrast, all four strains occurred in significant proportions among heterosexuals nationwide, pointing to an expansion of the HIV-1 epidemic from high-risk populations into the general population. CRF01_AE also replaced subtype B as the principal driver of infection among men-who-have-sex-with-men.

Conclusions

Our study provides the first comprehensive baseline data on the diversity and characteristics of HIV/AIDS epidemic in China, reflecting unique region- and risk group-specific transmission dynamics. The results provide information critical for designing effective prevention measures against HIV transmission.

Background

Although various HIV prevention programs targeting men who have sex with men (MSM) are operating in China, whether and how these programs are being utilized is unclear. This study explores participation of HIV prevention programs and influencing factors among MSM in two cities in China.

Methods

This is a mixed-method study conducted in Beijing and Chongqing. A qualitative study consisting of in-depth interviews with 54 MSM, 11 key informants, and 8 focus group discussions, a cross-sectional survey using respondent-driven sampling among 998 MSM were conducted in 2009 and 2010 respectively to elicit information on MSM’s perception and utilization of HIV prevention programs. Qualitative findings were integrated with quantitative multivariate factors to explain the quantitative findings.

Results

Fifty-six percent of MSM in Chongqing and 75.1% in Beijing ever participated in at least one type of HIV prevention program (P=0.001). Factors related to participation in HIV prevention programs included age, ethnicity, income, HIV risk perception, living with boyfriend, living in urban area, size of MSM social network, having talked about HIV status with partners, and knowing someone who is HIV positive. Reasons why MSM did not participate in HIV prevention programs included logistical concerns like limited time for participation and distance to services; program content and delivery issues such as perceived low quality services and distrust of providers; and, cultural issues like HIV-related stigma and low risk perception.

Conclusions

The study shows that there is much room for improvement in reaching MSM in China. HIV prevention programs targeting MSM in China may need to be more comprehensive and incorporate the cultural, logistic and HIV-related needs of the population in order to effectively reach and affect this population’s risk for HIV.

Background

Men who have sex with men (MSM) are at a substantial risk of HIV, given rising HIV prevalence in urban China. Adolescent and adult students often take HIV-related risk as part of sexual exploration. We compared the risks of HIV and syphilis infections and risky sexual behaviors between student and non-student among urban MSM.

Methods

Respondent driven sampling approach was used to recruit men who were self-identified as MSM in Chongqing Metropolitan City in southwestern China in 2009. Each participant completed a computer-assisted self-interview which collected demographic and behavioral data, and provided blood specimens for HIV and syphilis testing. Multivariable logistic regression analyses identified predictors for HIV and syphilis infections while comparing student and non-student MSM.

Results

Among 503 MSM participants, 36.4% were students, of whom 84.2% were in college. The adjusted prevalence of HIV infection was 5.5% (95% confidence interval [CI]: 2.1%–10.2%) in students and 20.9% (95% CI: 13.7%–27.5%) in non-students; the adjusted prevalence of syphilis was 4.4% (95% CI: 0.7%–9.0%) in students and 7.9% (95% CI: 3.6%–12.9%) in non-students (P = 0.12). Two groups had similar risky sexual behaviors such as number of sexual partners and exchanging sex for money. Multivariate analysis showed that students had lower HIV prevalence than non-students (adjusted odds ratio [AOR]: 0.3; 95% CI: 0.1–0.8) adjusting for age, ethnicity and other variables.

Conclusion

Student MSM have lower HIV and similar syphilis prevalence compared with non-student MSM. However, due to a shorter duration of sexual experience and high prevalence of at-risk sexual behaviors among student MSM, HIV risk might be quite high in students as in non-students.

Background

In the recent years, dramatic increases in HIV transmission among men who have sex with men (MSM) have been observed in China. Human papillomavirus (HPV) infection related anal cancer is more common among HIV-infected MSM as compared to the general population. However, HPV infection and anal cytology has been rarely studied in HIV-infected MSM in China.

Methods

HIV-infected MSM in Beijing, China were invited to participate in this study between January and April 2011. Anal swabs were collected for examining cytology and HPV genotypes.

Results

Ninety-five eligible participants with complete questionnaire and laboratory data were included in the analyses. Thirty six of them (37.9%) showed abnormal anal cytology as follows: atypical squamous cells of undetermined significance (ASC-US) in 19 (20.0%), atypical squamous cells but cannot exclude HSIL (ASC-H) in 1 (1.1%), low-grade squamous intraepithelial lesion (LSIL) in 15 (15.8%), and high-grade squamous intraepithelial lesion (HSIL) in 1 (1.1%). HPV6 (20.0%), HPV16 (10.9%), HPV56 (10.9%), HPV52 (9.1%) and HPV39 (9.1%) were observed most frequently among those with normal anal cytology, while different distribution was found in the ones with abnormal anal cytology as HPV6 (19.4%), HPV16 (19.4%), HPV45 (16.7%), HPV52 (16.7%) and HPV18 (11.1%). In addition, HPV16, HPV45, HPV52 and HPV18 were the most frequent high-risk types in patients with abnormal anal cytology. HPV multiplicity was found to be significantly related to the prevalence of abnormal anal cytology (p for trend = 0.04).

Conclusions

High prevalence of HPV infection and abnormal anal cytology was observed among HIV-infected MSM in China. Infection of multiple HPV types or high-risk types was found to be associated with an increased risk of abnormal anal cytology.

Objective

We investigated the awareness and acceptability of pre-exposure prophylaxis (PrEP) among men who have sex with men (MSM) and potential predicting factors.

Methods

This study was conducted among MSM in Beijing, China. Study participants, randomly selected from an MSM cohort, completed a structured questionnaire, and provided their blood samples to test for HIV infection and syphilis. Univariate logistic regression analyses were performed to evaluate the factors associated with willingness to accept (WTA) PrEP. Factors independently associated with willingness to accept were identified by entering variables into stepwise logistic regression analysis.

Results

A total of 152 MSM completed the survey; 11.2% had ever heard of PrEP and 67.8% were willing to accept it. Univariate analysis showed that age, years of education, consistent condom use in the past 6 months, heterosexual behavior in the past 6 months, having ever heard of PrEP and the side effects of antiretroviral drugs, and worry about antiretroviral drugs cost were significantly associated with willingness to accept PrEP. In the multivariate logistic regression model, only consistent condom use in the past 6 months (odds ratio [OR]: 0.31; 95% confidence interval [CI]: 0.13–0.70) and having ever heard of the side effects of antiretroviral drugs (OR: 0.30; 95% CI: 0.14–0.67) were independently associated with willingness to accept PrEP.

Conclusions

The awareness of PrEP in the MSM population was low. Sexual behavioral characteristics and knowledge about ART drugs may have effects on willingness to accept PrEP. Comprehensive prevention strategies should be recommended in the MSM community.

Background

Male circumcision (MC) has been shown to reduce the risk of female to male transmission of HIV. The goal of this survey was to explore the acceptability of MC among the Chinese and to identify factors associated with circumcision preference.

Methods

A cross-sectional survey was conducted between September 2009 and December 2010. We interviewed 2,219 male community participants, from three high HIV prevalence provinces in western China. A structured questionnaire was used to collect data on MC knowledge, willingness to accept MC, reasons to accept or refuse MC, and sexual behaviors and health. For those who refused MC, a health education intervention providing information on the benefits of circumcision was conducted. We used multiple logistic regression models to identify factors associated with the acceptability of MC.

Results

Of the respondents (n = 2,219), 44.6% (989/2,219) reported they would accept MC for the following reasons: promotion of female partners' hygiene (60.3%), redundant foreskin (59.4%), prevention of penile cancer (50.2%), enhanced sexual pleasure (41.4%), and protection against HIV and STDs (34.2%). The multivariable logistic regression showed that five factors were associated with MC willingness: long foreskin (OR = 15.98), residing in Xinjiang province (OR = 3.69), being younger than 25 (OR = 1.60), knowing hazards of redundant foreskin (OR = 1.78), and having a friend who underwent circumcision (OR = 1.36).

Conclusion

The acceptability of male circumcision was high among the general population in China. Our study elucidates the factors associated with circumcision preference and suggests that more health education campaigns about positive health effects are necessary to increase the MC rate in China.

A cross-sectional survey was conducted in 2007 among 504 drug users who were recruited mainly from detoxification centers in southwest China. About one-third (34.3%) of participants reported recent risky drug use behavior, which was defined as injecting drugs in the past 3 months, and more than one-fifth (21.6%) reported recent risky sexual behavior, or had multiple sexual partners in the past 30 days. Male sex (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.2–3.2) and more episodes of detoxification (OR, 3.7; 95% CI, 2.3–6.0) were associated with higher odds of risky drug use behavior, while unmarried status (OR, 1.7; 95% CI, 1.0–2.9), higher personal annual income (OR, 1.8; 95% CI, 1.1–2.8) and history of sexually transmitted infections (OR, 3.7; 95% CI, 2.1–6.6) were associated with higher odds of having risky sexual behavior. Subgroup analyses showed 15% participants who used drugs in the past 3 months also shared needles, and 77% participants who had multiple sexual partners in the past 30 days did not use condoms during sex with non-primary sexual partners. The study findings are useful for developing HIV risk reduction intervention programs among drug users.

Abstract

Recent data suggest that the prevalence of HIV/syphilis infections among men who have sex with men (MSM) in China increased rapidly. This cohort study was to assess the correlates of the incident infections for HIV, syphilis, and hepatitis B virus (HBV) among sexually active and HIV–negative MSM in China. A cohort of 507 HIV-seronegative MSM was recruited from November 2006 to February 2007. Sociodemographics, sexual and drug use behaviors, uptake of HIV-prevention services, and HIV, syphilis, and HBV seroconversions were assessed at 6- and 12- month follow-up. The incidence rates were 2.6 per 100 person-years for HIV, 16.9 per 100 person-years for syphilis, and 3.3 per 100 person-years for HBV. Multivariate Cox regression analyses showed that syphilis infection (hazard ratio [HR] = 3.6; 95% confidence interval [CI]: 1.1–11.6) and no perceived risk of HIV infection (HR = 6.0; 95% CI: 1.6–22.7) were independently associated with HIV seroconversion. Predictors for syphilis seroconversion included less education (HR = 1.87; 95% CI: 1.1–3.3), found male sex partners through bathhouses/public washrooms/parks (HR = 2.19; 95% CI: 1.2–4.0), drank alcohol 4 or more times monthly (HR = 1.95; 95% CI: 1.1–3.6), and had sexually transmitted diseases (HR = 2.65; 95% CI: 1.5–4.5). The only predictor for incident HBV seroconvension was having more male sex partners in the past 3 months (HR = 11.8; 95% CI: 1.5–90.4). Alarmingly high incidence rates of HIV, syphilis, and HBV were found among MSM concurrently with high prevalent risky behaviors and low uptakes of health care services. The findings of this study underscore the urgent needs for a comprehensive intervention strategy to curtail the rapid spread of HIV, syphilis, and HBV.

Background

Anal HPV infection, which contributes to the development of anal warts and anal cancer, is well known to be common among men who have sex with men (MSM), especially among those HIV positives. However, HIV and anal HPV co-infection among MSM has not been addressed in China.

Methods

A cross-sectional study was conducted in Beijing and Tianjin, China. Study participants were recruited using multiple methods with the collaboration of local volunteer organizations. Blood and anal swabs were collected for HIV-1 serological test and HPV genotyping.

Results

A total of 602 MSM were recruited and laboratory data were available for 578 of them (96.0%). HIV and anal HPV prevalence were 8.5% and 62.1%, respectively. And 48 MSM (8.3%) were found to be co-infected. The HPV genotypes identified most frequently were HPV06 (19.6%), HPV16 (13.0%), HPV52 (8.5%) and HPV11 (7.6%). Different modes of HPV genotypes distribution were observed with respect to HIV status. A strong dose-response relationship was found between HIV seropositivity and multiplicity of HPV genotypes (p<0.001), which is consistent with the observation that anal HPV infection was an independent predictor for HIV infection.

Conclusions

A high prevalence of HIV and anal HPV co-infection was observed in the MSM community in Beijing and Tianjin, China. Anal HPV infection was found to be independently associated with increased HIV seropositivity, which suggests the application of HPV vaccine might be a potential strategy to reduce the acquisition of HIV infection though controlling the prevalence of HPV.

Abstract

Male circumcision can reduce the risk of HIV acquisition among heterosexual men, but its effectiveness is uncertain in men who have sex with men (MSM). Additionally, its acceptability among Chinese men is unknown given a lack of history and cultural norms endorsing neonatal and adult circumcision. This study evaluated the willingness to participate in a clinical trial of circumcision among 328 Chinese MSM. Some 11.6% respondents reported having been circumcised, most of them due to a tight foreskin. Of 284 uncircumcised MSM, 16.9% said they were absolutely willing to participate, 26.4% were probably, 28.9% were probably not, and 27.8% were absolutely not; 81% said male circumcision would help maintain genital hygiene. The major motivators for willingness to participate included contribution to AIDS scientific research and getting free medical service. Men also had concerns about ineffectiveness of circumcision in reducing HIV/sexually transmitted infection (STI) risks and side effects of the surgery. Those who did not have a Beijing resident card (adjusted odds ratio [AOR], 1.99; 95% confidence interval [CI], 1.17–3.38), did not find sexual partners through the Internet (AOR, 2.13; 95% CI, 1.21–3.75), and were not concerned about the effectiveness of circumcision (AOR, 2.37; 95% CI, 1.34–4.19) were more likely to be willing to participate in a trial. The study suggests that circumcision is uncommon among Chinese MSM. Considerable community education will be needed in circumcision advocacy among MSM in China. A clinical trial for efficacy among MSM should be considered.

Background

Men who have sex with men (MSM) are much more likely to be infected with HIV than the general population. China has a sizable population of MSM, including gay, bisexual men, money boys and some rural workers. So reducing HIV infection in this population is an important component of the national HIV/AIDS prevention and control program.

Methods

We develop a mathematical model using a sex-role-preference framework to predict HIV infection in the MSM population and to evaluate different intervention strategies.

Results

An analytic formula for the basic reproduction ratio R0 was obtained; this yields R0 = 3.9296 in the current situation, so HIV will spread very fast in the MSM population if no intervention measure is implemented in a timely fashion. The persistence of HIV infection and the existence of disease equilibrium (or equilibria) are also shown. We utilized our model to simulate possible outcomes of antiretroviral therapy and vaccination for the MSM population. We compared the effects of these intervention measures under different assumptions about MSM behaviour. We also found that R0 is a decreasing function of the death rate of HIV-infected individuals, following a power law at least asymptotically.

Conclusion

HIV will spread very fast in the MSM population unless intervention measures are implemented urgently. Antiretroviral therapy can have substantial impact on the reduction of HIV among the MSM population, even if disinhibition is considered. The effect of protected sexual behaviour on controlling the epidemic in the MSM population largely depends on the sex-ratio preference of different sub-populations.

Summary

Background

Chinese injection drug users (IDUs) may be a proper candidate population for HIV vaccine trials.

Objective

To evaluate willingness to participate (WTP) in HIV vaccine trials among Chinese IDUs.

Methods

Questionnaire interviews were completed among 401 IDUs in Urumqi City in northwestern China in 2005.

Results

Overall 74.3% of participants said that they would be definitely willing to participate in HIV vaccine trials, 17.7% were probably willing, 6.2% were probably not willing, and remaining 1.8% were definitely not willing to join. Multivariate logistic regression analysis demonstrated that WTP was positively associated with having ever had sex with a drug use partner (adjusted odds ratio [AOR]: 1.8; 95% confidence interval [CI]: 1.04, 3.2), sharing needle and syringe with a new drug use partner in the past 3 months (AOR: 3.8; 95% CI: 1.2, 11.7), perceived family support for participation (AOR: 7.4; 95% CI: 4.3, 12.7), and perceived vaccine protection against HIV infection (AOR: 16.1; 95% CI: 3.7, 70.8), and was negatively associated with perceived risk of social stigma and isolation for participation (AOR: 0.3; 95% CI: 0.2, 0.5).

Conclusions

The stated WTP in hypothetical HIV vaccine trials was high among Chinese IDUs. Further studies are needed to evaluate actual enrollment into the trials.

To examine the correlates for syphilis and the prevalence for HIV, hepatitis B, hepatitis C among men-who-have-sex-with-men (MSM) in Beijing, China. A total of 541 MSM was recruited using peer-referral, community outreach, and Internet. Questionnaire-based interviews provided information including, demographics, sexual and other risk behaviors. HIV prevalence was 4.8%, syphilis 19.8%, HCV 0.4% and HBsAg 6.5%. The median number of lifetime male sex partners was ten. In the past 3 months, 20.7% drank alcohol ≥1 times per week. In the past month, 21.3 and 14.6% had unprotected anal intercourse with regular and casual male sex partners, respectively. Syphilis infection was associated with less education, alcohol use, finding male sex partners through bathhouses/public washrooms/parks, and diagnoses of sexual transmitted diseases (STDs). Syphilis is now epidemic among Beijing's MSM. Prevention efforts are urgent as HIV prevalence is already near 5%. Education, condom promotion, STD control, and alcohol-related intervention are needed urgently.

Summary

OBJECTIVE

To assess differences of HIV risk between ethnicities in northwestern China.

METHOD

Cross-sectional serosurvey and structured questionnaire interview of 383 injection drug users of either Han or Uigur ethnicity in Urumqi, Xinjiang.

RESULTS

Both Uigur minority ethnicity and residence in a Uigur or mixed Uigur/Han community were independently associated with higher HIV risk.

CONCLUSION

HIV prevention programs should give special focus on minority ethnic drug users and their communities.

Male circumcision can reduce the risk of HIV acquisition among heterosexual men, but its effectiveness is uncertain in men who have sex with men (MSM). Additionally, its acceptability among Chinese men is unknown given a lack of history and cultural norms endorsing neonatal and adult circumcision. This study evaluated the willingness to participate in a clinical trial of circumcision among 328 Chinese MSM. Some 11.6% respondents reported having been circumcised, most of them due to a tight foreskin. Of 284 uncircumcised MSM, 16.9% said they were absolutely willing to participate, 26.4% were probably, 28.9% were probably not, and 27.8% were absolutely not; 81% said male circumcision would help maintain genital hygiene. The major motivators for willingness to participate included contribution to AIDS scientific research and getting free medical service. Men also had concerns about ineffectiveness of circumcision in reducing HIV/sexually transmitted infection (STI) risks and side effects of the surgery. Those who did not have a Beijing resident card (adjusted odds ratio [AOR], 1.99; 95% confidence interval [CI], 1.17–3.38), did not find sexual partners through the Internet (AOR, 2.13; 95% CI, 1.21–3.75), and were not concerned about the effectiveness of circumcision (AOR, 2.37; 95% CI, 1.34–4.19) were more likely to be willing to participate in a trial. The study suggests that circumcision is uncommon among Chinese MSM. Considerable community education will be needed in circumcision advocacy among MSM in China. A clinical trial for efficacy among MSM should be considered.

Background

It remains controversial how HCV coinfection influences the disease progression during HIV-1 infection. This study aims to define the influence of HCV infection on the replication of HIV-1 and the disease progression in HIV-infected former plasma donors (FPDs) naïve to ART.

Methodology/Principal Findings

168 HIV-1-infected FPDs were enrolled into a cohort study from Anhui province in central China, and thereafter monitored at month 3, 9, 15, 21 and 33. Fresh whole blood samples were used for CD4+ T-cell counting. Their plasma samples were collected and stored for quantification of HIV-1 viral loads and for determination of HCV and Toxoplasma. Out of 168 HIV-infected FBDs, 11.9% (20 cases), 80.4% (135 cases) and 7.7% (13 cases) were infected with HIV-1 alone, HIV-1/HCV and HIV/HCV/Toxoplasma, respectively. During the 33-month follow-up, only 35% (7 out of 20 cases) HIV-1 mono-infected subjects remained their CD4+ T-cell counts above 200 cells/µl and retained on the cohort study, which was significantly lower than 56% (75 out of 135 cases) for HIV/HCV group and 69% (9 out of 13 cases) for HIV/HCV/Toxoplasma group (p<0.05). CD4+ T cells in HIV mono infection group were consistently lower than that in HIV/HCV group (p = 0.04, 0.18, 0.03 and 0.04 for baseline, month 9, month 21 and month 33 visit, respectively). In accordance with those observations, HIV viral loads in HIV mono-infection group were consistently higher than that in HIV/HCV group though statistical significances were only reached at baseline (p = 0.04).

Conclusions/Significance

These data indicated HCV coinfection with HIV-1 is associated with the slower disease progression at the very late stage when comparing with HIV-1 mono-infection. The coinfection of Toxoplasma with HIV and HCV did not exert additional influence on the disease progression. It will be highly interesting to further explore the underlying mechanism for this observation in the future.

Background

The characterization of HIV-1-specific T cell responses in people infected with locally circulating HIV-1 strain will facilitate the development of HIV-1 vaccine. Sixty intravenous drug users infected with HIV-1 circulating recombinant form 07_BC (CRF07_BC), which has been spreading rapidly in western China from north to south, were recruited from Xinjiang, China to assess the HIV-1-specific T cell responses at single peptide level with overlapping peptides (OLP) covering the whole concensus clades B and C proteome.

Results

The median of the total magnitude and total number of OLPs recognized by CTL responses were 10925 SFC/million PBMC and 25 OLPs, respectively, when tested by clade C peptides, which was significantly higher than when tested by clade B peptides. The immunodominant regions, which cover 14% (58/413) of the HIV-1 proteome, are widely distributed throughout the HIV-1 proteome except in Tat, Vpu and Pol-PR, with Gag, Pol-RT, Pol-Int and Nef being most frequently targeted. The subdominant epitopes are mostly located in p24, Nef, integrase, Vpr and Vif. Of the responses directed to clade C OLPs, 61.75% (972/1574) can be observed when tested with corresponding clade B OLPs. However, Pol-PR and Vpu tend to be targeted in the clade B sequence rather than the clade C sequence, which is in line with the recombinant pattern of CRF07_BC. Stronger and broader CTL responses in subjects with CD4 cell counts ranging from 200 to 400/mm3 were observed when compared to those with less than 200/mm3 or more than 400/mm3, though there have been no significant correlations identified between the accumulative CTL responses or overall breadth and CD4 cell count or plasma viral load.

Conclusion

This is the first study conducted to comprehensively address T cell responses in Chinese subjects infected with HIV-1 CRF07_BC in which subtle differences in cross-reactivity were observed, though similar patterns of overall immune responses were demonstrated with clade B infected populations. The immunodominant regions identified in this population can facilitate future HIV-1 vaccine development in China.

Objective

To estimate HIV prevalence among injecting drug users (IDUs) in a drug trafficking city in southwest Sichuan Province, China.

Methods

A total of 314 IDUs was invited to participate in the cross-sectional survey in 2004 through community outreach recruitment and peer referrals. Blood sample was taken for HIV antibody testing and a structured questionnaire was administered to collect information on socio-demographics, drug using and sexual behaviors.

Results

HIV prevalence among IDUs was 17.8% (56/314), about one half higher than that in previous survey in 2002 (11.3%, 43/379). Yi and other minority ethnicity (Odds ratio [OR], 3.1; 95% confidence interval [CI], 1.7–5.8; P < 0.001), and total times of sharing injecting equipments 1–9 times versus none, OR, 2.7; 95% CI 1.2–6.2; P = 0.02; and ≥10 times versus none, OR, 7.5; 95% CI, 3.2–17.7; P < 0.001) were independent risk factors for HIV infection.

Conclusion

IDUs with high prevalence rates of HIV and equipment sharing behavior in the drug trafficking city may serve a source for further spread of HIV to other areas in China. The increasing trend of HIV epidemic among IDUs underscores the urgency of scaling up interventions.