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The HIV prevalence and incidence among men who have sex with men (MSM) in China are high. Unprotected anal intercourse (UAI) with a regular male sex partner (RP), a significant predictor of HIV sero-conversion, was high yet under-emphasized among MSM having RP (MSMRP). The present cross-sectional survey interviewed 307 HIV negative MSMRP recruited through convenient sampling from multiple sources, including venue-based outreaching, online recruitment, and referrals made by peers, in Beijing and Chengdu, China. Among MSMRP, the prevalence of UAI with RP in the last three months was 52.4%. The results of the multivariate analysis showed that trust and intimacy within the relationship with RP and presence of clinical depression symptoms were positively associated with UAI with RP in the last three months. Other associated scalar factors derived from the Theory of Planned Behavior were related to perceptions on condom use, including positive attitudes toward condom use (a negative association), subjective norm of the perception that MSM do not usually use condoms during anal intercourse with RP (a positive association), perceived behavioral control over condom use with RP (a negative association), and behavioral intention to use condoms with RP in the coming three months (a negative association). It is seen that MSMRP were at high risk of HIV/STD transmission. The associated factors hence involved those related to perceptions about condom use, mental health, and interpersonal relationship. Future interventions should take these multi-dimensional factors into account. In particular, future research to test the efficacy of couple-based interventions that include mental health elements needs to be conducted, as trust and intimacy within the relationship were associated with UAI among MSMRP, and mental health problems may exist for both the MSMRP and their RP.  相似文献   

3.

Background

Syphilis co-infection risk has increased substantially among HIV-infected men who have sex with men (MSM). Frequent screening for syphilis and treatment of men who test positive might be a practical means of controlling the risk of infection and disease sequelae in this population.

Purpose

We evaluated the cost-effectiveness of strategies that increased the frequency and population coverage of syphilis screening in HIV-infected MSM receiving HIV care, relative to current standard of care.

Methods

We developed a state-transition microsimulation model of syphilis natural history and medical care in HIV-infected MSM receiving care for HIV. We performed Monte Carlo simulations using input data derived from a large observational cohort in Ontario, Canada, and from published biomedical literature. Simulations compared usual care (57% of the population screened annually) to different combinations of more frequent (3- or 6-monthly) screening and higher coverage (100% screened). We estimated expected disease-specific outcomes, quality-adjusted survival, costs, and cost-effectiveness associated with each strategy from the perspective of a public health care payer.

Results

Usual care was more costly and less effective than strategies with more frequent or higher coverage screening. Higher coverage strategies (with screening frequency of 3 or 6 months) were expected to be cost-effective based on usually cited willingness-to-pay thresholds. These findings were robust in the face of probabilistic sensitivity analyses, alternate cost-effectiveness thresholds, and alternate assumptions about duration of risk, program characteristics, and management of underlying HIV.

Conclusions

We project that higher coverage and more frequent syphilis screening of HIV-infected MSM would be a highly cost-effective health intervention, with many potentially viable screening strategies projected to both save costs and improve health when compared to usual care. The baseline requirement for regular blood testing in this group (i.e., for viral load monitoring) makes intensification of syphilis screening appear readily practicable.  相似文献   

4.

Background

Since 2005, Australian clinicians were advised to undertake quarterly syphilis testing for all sexually active HIV-positive men who have sex with men (MSM). We describe differences in syphilis testing frequency among HIV-positive MSM by clinic testing policies since this recommendation.

Methods

Three general practices, two sexual health clinics and two hospital HIV outpatient clinics provided data on HIV viral load and syphilis testing from 2006–2010. Men having ≥1 viral load test per year were included; >95% were MSM. We used Chi-2 tests to assess changes in syphilis testing frequency over time, and differences by clinic testing policy (opt-out, opt-in and risk-based).

Results

The proportion of men having HIV viral loads with same-day syphilis tests increased from 37% in 2006 to 63% in 2007 (p<0.01) and 68–69% thereafter. In 2010, same-day syphilis testing was highest in four clinics with opt-out strategies (87%, range:84–91%) compared with one clinic with opt-in (74%, p = 0.121) and two clinics with risk-based strategies (22%, range:20–24%, p<0.01). The proportion of men having ≥3 syphilis tests per year increased from 15% in 2006 to 36% in 2007 (p<0.01) and 36–38% thereafter. In 2010, the proportion of men having ≥3 syphilis tests in a year was highest in clinics with opt-out strategies (48%, range:35–59%), compared with opt-in (39%, p = 0.121) and risk-based strategies (8.4%, range:5.4–12%, p<0.01).

Conclusion

Over five years the proportion of HIV-positive men undergoing syphilis testing at recommended frequencies more than doubled, and was 5–6 times higher in clinics with opt-out and opt-in strategies compared with risk-based policies.  相似文献   

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BackgroundLittle is known about the socio-behavioral risk factors for HIV acquisition among hard-to-reach men who have sex with men (MSM) population in India, particularly from the densely populated eastern part. Thus to measure the burden and correlates of HIV among MSM in West Bengal state of eastern India, a cross-sectional analysis of the national HIV Sentinel Surveillance (HSS) data was conducted.MethodsIn 2011, between July and September, involving all sentinel sites of the state, 1237 consenting MSM were anonymously interviewed and tested for HIV following national guidelines. Using a short, structured questionnaire, information was collected on socio-behavioral factors along with sexual practices and was analyzed to determine burden of HIV and the role of its socio-behavioral correlates on HIV acquisition.ResultsAmong participants, mean age was 23.4 years, 44.55% were “Kothis” (usually receptive partner) and 25.1% admitted receiving money for sex with man. HIV sero-positivity was 5.09%. Using logistic regression method, for both bivariate and multivariate (with saturated model) analyses, transport-workers [adjusted odds ratio (AOR)=8.95, 95% confidence interval (95%CI): 1.09-73.71), large business-owners/self-employed (AOR=8.46, 95%CI: 1.25-57.49), small business-owners/cultivators (AOR=7.90, 95%CI: 1.67-37.38), those who visited the sentinel site for official purposes (AOR=7.60, 95%CI: 1.21-47.83) and paying money for having sex with men (AOR=3.03, 95%CI: 1.10-8.33) were strongly associated with higher HIV sero-positivity with than their counterparts. Using the parsimonious model for multivariate analysis, Kothis (AOR=4.64, 95%CI: 1.03-20.89), paying (AOR=2.96, 95%CI: 1.15-7.58) or receiving (AOR=2.06, 95%CI: 1.06-3.99) money for having sex with a man were associated with higher risk of HIV.ConclusionsFocused intervention targeting the high risk MSM subgroups including Kothis, transport-workers, business-owners/self-employed and those who exchanged money for having sex with men, seemed to be the need of the hour for preventing the spread of HIV infection within and from this understudied population.  相似文献   

7.

Background

Despite preventive efforts, HIV incidence remains high among men who have sex with men (MSM) in industrialized countries. Condoms are an important element in prevention but, given the high frequency of condom use and their imperfect effectiveness, a substantial number and proportion of HIV transmissions may occur despite condoms. We developed a model to examine this hypothesis.

Methods

We used estimates of annual prevalent and incident HIV infections for MSM in Ontario. For HIV-negative men, we applied frequencies of sexual episodes and per-contact HIV transmission risks of receptive and insertive anal sex with and without a condom and oral sex without a condom. We factored in the proportion of HIV-infected partners receiving antiretroviral therapy and its impact in reducing transmissibility. We used Monte-Carlo simulation to determine the plausible range for the proportion of HIV transmissions for each sexual practice.

Results

Among Ontario MSM in 2009, an estimated 92,963 HIV-negative men had 1,184,343 episodes of anal sex with a condom and 117,133 anal sex acts without a condom with an HIV-positive partner. Of the 693 new HIV infections, 51% were through anal sex with a condom, 33% anal sex without a condom and 16% oral sex. For anal sex with a condom, the 95% confidence limits were 17% and 77%.

Conclusions

The proportion of HIV infections related to condom failure appears substantial and higher than previously thought. That 51% of transmissions occur despite condom use may be conservative (i.e. low) since we used a relatively high estimate (87.1%) for condom effectiveness. If condom effectiveness were closer to 70%, a value estimated from a recent CDC study, the number and proportion of HIV transmissions occurring despite condom use would be much higher. Therefore, while condom use should continue to be promoted and enhanced, this alone is unlikely to stem the tide of HIV infection among MSM.  相似文献   

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Background

The coverage of HIV testing among Chinese men who have sex with men (MSM) remains low after the scale-up of free HIV testing at government-sponsored testing sites. We evaluated the feasibility of home-based HIV self-testing and the willingness to be HIV tested at community-based organizations (CBO).

Methods

We recruited MSM via on-line advertisement, where they completed an on-line informed consent and subsequent questionnaire survey. Eligible MSM received HIV rapid testing kits by mail, performed the test themselves and reported the result remotely.

Results

Of the 220 men taking a home-based HIV self-testing, 33 MSM (15%) were seropositive. Nearly 65% of the men reported that they were willing to take HIV testing at CBO, while 28% preferred receiving free HIV testing in the government programs at local Centers for Disease Control and Prevention (CDC). Older and lower-income MSM, those who self-reported homosexual orientation, men with no history of sexually transmitted diseases and a lower number of sexual partners in the past six months were associated with preference for taking HIV testing at CBOs. The top three self-reported existing barriers for HIV testing were: no perception of HIV risk (56%), fear of an HIV positive result being reported to the government (41%), and fear of a positive HIV test result (36%).

Conclusion

Home-based HIV self-testing is an alternative approach for increasing the coverage of HIV testing among Chinese MSM. CBO-based HIV testing is a potential alternative, but further studies are needed to evaluate its feasibility.  相似文献   

10.

Background

Publications on Libya’s HIV epidemic mostly examined the victims of the tragic nosocomial HIV outbreak in the 1990s and the related dispute about the detention of foreign medical workers. The dispute resolution in 2003 included an agreement with the European Union on humanitarian cooperation and the development of Libya’s first National HIV Strategy. As part of this we conducted Libya’s first bio-behavioural survey among men having sex with men (MSM) and female sex workers (FSW).

Methods

Using respondent-driven sampling, we conducted a cross-sectional study to estimate the prevalence of HIV, hepatitis B virus (HBV), hepatitis C virus (HCV), and related risk factors among 227 MSM and 69 FSW in Tripoli (FSW recruitment ended prematurely due to the political events in 2011).

Results

For MSM we estimated an HIV prevalence of 3.1%, HBV prevalence of 2.9%, and HCV prevalence of 7.3%, and for FSW an HIV prevalence of 15.7%, HBV prevalence of 0%, and HCV prevalence of 5.2%. We detected high levels of risk behaviours, poor HIV-related knowledge, high stigma and lack of prevention programmes. These results must be interpreted in the context of the political situation which prohibited reaching an ideal sample size for FSW.

Conclusion

There is urgent need to implement an effective National HIV Strategy informed by the results of this research. The risk of transmission within different risk groups and to the general population may be high given the recent military events that led to increased violence, migration, and the disruption of essential HIV-related services.  相似文献   

11.

Objective

Sexually transmitted infections (STI) are common among HIV-infected men who have sex with men (MSM). While behavioral factors are important in STI acquisition, other biological factors such as immune modulation due to chronic viral infection may further predispose to STI acquisition.

Design

Post Hoc analysis including data collected over 12 months of follow-up from 131 HIV-infected MSM receiving antiretroviral therapy and screened for incident bacterial STI every 3 months.

Methods

Genital secretions collected at baseline were used to measure herpesvirus replication and inflammatory cytokines. Baseline predictors of STI were determined using survival analysis of time to incident STI.

Results

All participants were seropositive for cytomegalovirus (CMV), and 52% had detectable genital CMV at baseline. Thirty-five individuals acquired STI during follow-up, sometimes with multiple pathogen (17 syphilis, 21 gonorrhea, 14 chlamydia). Syphilis acquisition was associated with genital CMV replication at baseline (19.1% CMV-shedders versus 4.8% non-shedders, p=0.03) and younger age (p=0.02). Lower seminal MCP-1 was associated with higher seminal CMV levels and with syphilis acquisition (p<0.01). For syphilis acquisition, in multivariable Cox-Proportional Hazard model adjusted hazard rates were 3.56 (95%CI:1.00–12.73) for baseline CMV replication and 2.50 (0.92–6.77) for younger age.

Conclusions

This post hoc analysis suggest that CMV-associated decrease in seminal MCP-1 levels might predispose HIV-infected MSM to syphilis acquisition, but not other STI. Future studies should determine underlying mechanisms and if a causal association exists.  相似文献   

12.

Objective

Men who have sex with men (MSM) practice role segregation – insertive or receptive only sex positions instead of a versatile role - in several international settings where candidate biomedical HIV prevention interventions (e.g., circumcision, anal microbicide) will be tested. The effects of these position-specific interventions on HIV incidence are modeled.

Materials and Methods

We developed a deterministic compartmental model to predict HIV incidence among Indian MSM using data from 2003–2010. The model’s sex mixing matrix was derived from network data of Indian MSM (n = 4604). Our model captures changing distribution of sex roles over time. We modeled microbicide and circumcision efficacy on trials with heterosexuals.

Results

Increasing numbers of versatile MSM resulted in little change in HIV incidence over 20 years. Anal microbicides and circumcision would decrease the HIV prevalence at 10 years from 15.6% to 12.9% and 12.7% respectively. Anal microbicides would provide similar protection to circumcision at the population level despite lower modeled efficacy (54% and 60% risk reduction, respectively). Combination of the interventions were additive: in 5 years, the reduction in HIV prevalence of the combination (−3.2%) is almost the sum of their individual reductions in HIV prevalence (−1.8% and −1.7%).

Conclusions

MSM sex role segregation and mixing, unlike changes in the sex role distribution, may be important for evaluating HIV prevention interventions in international settings. Synergies between some position-specific prevention interventions such as circumcision and anal microbicides warrant further study.  相似文献   

13.

Background

New HIV infections in men who have sex with men (MSM) have increased in Switzerland since 2000 despite combination antiretroviral therapy (cART). The objectives of this mathematical modelling study were: to describe the dynamics of the HIV epidemic in MSM in Switzerland using national data; to explore the effects of hypothetical prevention scenarios; and to conduct a multivariate sensitivity analysis.

Methodology/Principal Findings

The model describes HIV transmission, progression and the effects of cART using differential equations. The model was fitted to Swiss HIV and AIDS surveillance data and twelve unknown parameters were estimated. Predicted numbers of diagnosed HIV infections and AIDS cases fitted the observed data well. By the end of 2010, an estimated 13.5% (95% CI 12.5, 14.6%) of all HIV-infected MSM were undiagnosed and accounted for 81.8% (95% CI 81.1, 82.4%) of new HIV infections. The transmission rate was at its lowest from 1995–1999, with a nadir of 46 incident HIV infections in 1999, but increased from 2000. The estimated number of new infections continued to increase to more than 250 in 2010, although the reproduction number was still below the epidemic threshold. Prevention scenarios included temporary reductions in risk behaviour, annual test and treat, and reduction in risk behaviour to levels observed earlier in the epidemic. These led to predicted reductions in new infections from 2 to 26% by 2020. Parameters related to disease progression and relative infectiousness at different HIV stages had the greatest influence on estimates of the net transmission rate.

Conclusions/Significance

The model outputs suggest that the increase in HIV transmission amongst MSM in Switzerland is the result of continuing risky sexual behaviour, particularly by those unaware of their infection status. Long term reductions in the incidence of HIV infection in MSM in Switzerland will require increased and sustained uptake of effective interventions.  相似文献   

14.

Background

The HIV-epidemic among MSM in China has worsened. In this key population, prevalence of HSV-2 and syphilis infection and co-infection with HIV is high.

Methods

A longitudinal study was conducted (n = 962) in Beijing, China, with three overlapping cohorts (n = 857, 757 and 760) consisting of MSM that were free from pairs of infections of concern (i.e. HIV-HSV-2, HIV-syphilis, HSV-2-syphilis) at baseline to estimate incidence of HIV, HSV-2, syphilis, and those of co-infection.

Results

The incidence of HIV, HSV-2 and syphilis in the overall cohort was 3.90 (95% CI = 2.37, 5.43), 7.87 (95% CI = 5.74, 10.00) and 6.06 (95% CI = 4.18, 7.94) cases per 100 person-years (PYs), respectively. The incidence of HIV-HSV-2, HIV-Syphilis and HSV-2-Syphilis co-infections was 0.30 (95% CI = 0.29, 0.88), 1.02 (95% CI = 0.13, 2.17) and 1.41 (95% CI: 0.04, 2.78) cases per 100 PYs, respectively, in the three sub-cohorts constructed for this study.

Conclusions

The incidence of HIV, HSV-2 and syphilis was very high and those of their co-infections were relatively high. Such co-infections have negative impacts on the HIV/STI epidemics. Prevention practices need to take such co-infections into account.  相似文献   

15.
BackgroundHIV testing is the first point of HIV treatment entry for HIV-infected individuals and an avenue to engage persons at risk in prevention. In China, where the prevalence of HIV among men who have sex with men (MSM) has been rising over the last decade, uptake of HIV testing has been low.MethodsWe examined changes in HIV testing in the preceding 12 months through two cross-sectional surveys conducted among MSM in Nanjing, Jiangsu province, China in 2008 and 2012. Respondent-driven sampling (RDS) was used to recruit participants. Questionnaire interviews and venous blood were collected to measure HIV testing, risk behaviors, and prevalence of HIV, syphilis, and HSV-2.ResultsA total of 430 and 589 MSM were surveyed in 2008 and 2012, respectively, with comparable samples in each round with respect to demographic characteristics. HIV testing in the past 12 months increased significantly from 20.1% (95% CI 13.3–26.8) in 2008 to 46.0% (95% CI 39.3–51.4, p < 0.001) in 2012. HIV prevalence was stable, at 6.6% (95% CI 2.5–11.3) in 2008 and 10.1% (95% CI 6.6–13.9, p = 0.240) in 2012, as was syphilis (14.3% in 2008 vs. 9.9% in 2012, p = 0.240). HSV-2 prevalence (18.6% in 2008 vs. 10.2% in 2012, p = 0.040) and self-reported STI in the last year (24.3% in 2008 vs. 14.3% in 2012, p = 0.020) significantly decreased. Changes in reported sexual behaviors were mixed and the profiles of who did and did not test varied between 2008 and 2012.ConclusionsHIV testing uptake more than doubled among MSM in Nanjing from 2008 to 2012 –a period of massive promotion and scale up of testing programs for MSM. However, additional efforts are still needed to further increase the proportion of men being not only tested but also undergoing repeat testing if they engage in continued risk taking behavior.  相似文献   

16.
To determine uptake of home sampling kit (HSK) for STI/HIV compared to clinic-based testing, whether the availability of HSK would increase STI testing rates amongst HIV infected MSM, and those attending a community-based HIV testing clinic compared to historical control. Prospective observational study in three facilities providing STI/HIV testing services in Brighton, UK was conducted. Adult MSM attending/contacting a GUM clinic requesting an STI screen (group 1), HIV infected MSM attending routine outpatient clinic (group 2), and MSM attending a community-based rapid HIV testing service (group 3) were eligible. Participants were required to have no symptomatology consistent with STI and known to be immune to hepatitis A and B (group 1). Eligible men were offered a HSK to obtain self-collected specimens as an alternative to routine testing. HSK uptake compared to conventional clinic-based STI/HIV testing in group 1, increase in STI testing rates due to availability of HSK compared to historical controls in group 2 and 3, and HSK return rates in all settings were calculated. Among the 128 eligible men in group 1, HSK acceptance was higher (62.5% (95% CI: 53.5–70.9)) compared to GUM clinic-based testing (37.5% (95% CI: 29.1–46.5)), (p = 0.0004). Two thirds of eligible MSM offered an HSK in all three groups accepted it, but HSK return rates varied (highest in group 1, 77.5%, lowest in group 3, 16%). HSK for HIV testing was acceptable to 81% of men in group 1. Compared to historical controls, availability of HSK increased the proportion of MSM testing for STIs in group 2 but not in group 3. HSK for STI/HIV offers an alternative to conventional clinic-based testing for MSM seeking STI screening. It significantly increases STI testing uptake in HIV infected MSM. HSK could be considered as an adjunct to clinic-based services to further improve STI/HIV testing in MSM.  相似文献   

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ObjectiveTo evaluate current club drug use and its potential association with the transmission of HIV/STD among Changsha men who have sex with men (MSM).MethodA cross-sectional survey was conducted by using self-administered questionnaires including information regarding socio-demographics, club drug use, high-risk behaviors, and HIV/STD infections. Multiple methods including venue-based, peer referral using “snowball” techniques, and internet advertisements were used to recruit study participants.ResultsOf the 826 participants, 177 (21.4%) reported that they had used club drugs at some time before or during sex in the past six months. MSM with young age, low education level, and seeking partners through the internet or bars were the main population who used drugs. Poppers were the most common drug used among Changsha MSM. The prevalence of HIV, syphilis, and herpes simplex virus-2 were higher among drug users. There were no significant differences in unprotected sexual intercourse and condom use between drug users and non-users. Compared with non-users, risk behaviors such as group sex, multiple sex partners, and sex with foreigners were more frequent among drug users.ConclusionClub drug use is common among Changsha MSM, and is related to unsafe sex activities and HIV/STD infection. It is necessary to build novel targeted HIV prevention strategies to monitor and reduce club drug use among MSM.  相似文献   

20.

Objective

To examine homosexual and heterosexual behaviors, behavioral networks and HIV infection among men who have sex with men (MSM) in Eastern China.

Methods

A cross-sectional survey was conducted among MSM in 2013 in a rural prefecture of Zhejiang province. Participants were interviewed for their sexual behaviors and sexual networks and were tested for HIV infection.

Results

A total of 620 MSM from gay bath houses and bars participated in the survey. Of them, 58.2% aged 18 to 39 years and 49.5% were currently married with a female. The age of first homosexual contact was 26.7 years on average, ranging from 12 to 66 years. 91.0% had multiple male sex partners and 86.1% also had female sex partners in lifetime. 70 (11.3%) of the participants were tested HIV-positive. A total of 620 independent egocentric sexual networks involving 620 study participants and 1,971 reported sexual partners in the past 12 months were constructed, including 70 networks for the 70 HIV-positive participants with their 221 sexual partners and 550 networks for the 550 HIV-negative participants with their 1,750 sexual partners. The median network degree was 3 (IQR 2-4) overall and was not different between HIV-positive participants (Median: 3; IQR: 2-4) and HIV-negative participants (Median: 3; IQR: 2-4) (Mann-Whitney test, Z=-0.015, P=0.998). The proportion of networks with a multiple male sexual partnership was 63.7% overall, 62.8% for HIV-positive participants and 63.8% for HIV-negative participants (χ2=0.025, P=0.875). The proportion of networks with both male and female sexual partners was 44.8% overall, 47.1% for HIV-positive participants and 44.5% for HIV-negative participants (χ2=0.169, P=0.681). Consistent condom use and knowledge of HIV infection status were rare within the network partners.

Conclusions

The currently high HIV prevalence and complicated bisexual networks among MSM in the study area provides enhanced evidence for developing tailored prevention strategies for HIV transmission among and beyond the MSM population.  相似文献   

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