The effects of free condom distribution on HIV and other sexually transmitted infections in men who have sex with men.
ABSTRACT: BACKGROUND:HIV and other sexually transmitted infections remain a burden on men who have sex with men in the era of effective combination antiretroviral therapy. New prevention efforts are therefore needed. One of these approaches is the current country-wide free condom distribution at gay bars with darkrooms and gay saunas in the Netherlands. This study assessed the effects of free condom distribution on incidence and burden of disease of HIV and other sexually transmitted infections. METHODS:A static model was constructed to calculate the impact of free condom distribution on HIV, hepatitis C, chlamydia, gonorrhoea, and syphilis among men who have sex with men visiting these venues. Outcomes included new infections averted and disability-adjusted life years averted. Scenario studies were performed to predict the effects of a further increase of condom use, condom effectiveness and coverage. Lastly, cost-effectiveness and sensitivity analyses were performed. RESULTS:Our model showed that condom use at public sex venues increased after the intervention. Annual incidence risk decreased, ranging from 5.73% for gonorrhoea to 7.62% for HIV. The annual number of new infections averted was largest for chlamydia and gonorrhoea (261 and 394 infections, respectively), but 42 new HIV infections were averted as well. In scenarios where condom use and condom effectiveness were further increased, the number of infections reduced more extensively. Over 99% of the decrease in burden of disease was due to HIV. The intervention was cost-effective and cost-saving (for every €1 spent on condom distribution, €5.51 was saved) and remained this in all sensitivity analyses. CONCLUSIONS:Free condoms at public sex venues could reduce the transmission of HIV and other sexually transmitted infections. Condom distribution is an affordable and easily implemented intervention that could reduce the burden of disease in men who have sex with men substantially.
Project description:<h4>Aims</h4>To determine the effects of 1) a condom distribution program and 2) a condom distribution program combined with opt-out sexually transmitted infection (STI) screening on the transmission and prevalence of STIs in a prison system.<h4>Methods</h4>Using data from an implementation evaluation of a state-wide prison condom program and parameter estimates from available literature, a deterministic model was developed to quantify the incidence and prevalence of sexually transmitted HIV, hepatitis B, chlamydia, syphilis and gonorrhoea across 14 Victorian prisons. The model included individual prison populations (by longer (>2 years) or shorter sentence lengths) and monthly prisoner transfers. For each STI, simulations were compared: without any intervention; with a condom distribution program; and with a combined condom and opt-out STI screening at prison reception intervention program.<h4>Results</h4>Condoms reduced the annual incidence of syphilis by 99% (N = 66 averted cases); gonorrhoea by 98% (N = 113 cases); hepatitis B by 71% (N = 5 cases); chlamydia by 27% (N = 196 cases); and HIV by 50% (N = 2 cases every 10 years). Condom availability changed the in-prison epidemiology of gonorrhoea and syphilis from self-sustaining to levels unlikely to result in infection outbreaks; however, condoms did not reduce chlamydia prevalence below a self-sustaining level due to its high infectiousness, high prevalence and low detection rate. When combined with a screening intervention program, condoms reduced chlamydia prevalence further, but not below a self-sustaining level. The low prevalence of HIV and hepatitis B in Australian prisons meant the effects of condoms were predicted to be small.<h4>Conclusion</h4>Condoms are predicted to effectively reduce the incidence of STIs in prison and are predicted to control syphilis and gonorrhoea transmission, however even combined with a screening on arrival program may be insufficient to reduce chlamydia prevalence below self-sustaining levels. To control chlamydia transmission additional screening of the existing prison population would be required.
Project description:The degree to which adult medical male circumcision (MC) programs can reduce new HIV infections in a moderate HIV prevalence country like Papua New Guinea (PNG) are uncertain especially given the widespread prevalence of longitudinal foreskin cuts among adult males. We estimated the likely impact of a medical MC intervention in PNG using a mathematical model of HIV transmission. The model was age-structured and incorporated separate components for sex, rural/urban, men who have sex with men and female sex workers. Country-specific data of the prevalence of foreskin cuts, sexually transmitted infections, condom usage, and the acceptability of MC were obtained by our group through related studies. If longitudinal foreskin cutting has a protective efficacy of 20% compared to 60% for MC, then providing MC to 20% of uncut males from 2012 would require 376,000 procedures, avert 7,900 HIV infections by 2032, and require 143 MC per averted infection. Targeting uncut urban youths would achieve the most cost effective returns of 54 MC per HIV infection averted. These numbers of MC required to avert an HIV infection change little even with coverage up to 80% of men. The greater the protective efficacy of longitudinal foreskin cuts against HIV acquisition, the less impact MC interventions will have. Dependent on this efficacy, increasing condom use could have a much greater impact with a 10 percentage point increase averting 18,400 infections over this same period. MC programs could be effective in reducing HIV infections in PNG, particularly in high prevalence populations. However the overall impact is highly dependent on the protective efficacy of existing longitudinal foreskin cutting in preventing HIV.
Project description:INTRODUCTION:Understanding the impact of past interventions and how it affected transmission dynamics is key to guiding prevention efforts. We estimated the population-level impact of condom, antiretroviral therapy (ART), and prevention of mother-to-child transmission activities on HIV transmission and the contribution of key risk factors on HIV acquisition and transmission. METHODS:An age-stratified dynamical model of sexual and vertical HIV transmission among the general population, female sex workers (FSW), and men who have sex with men was calibrated to detailed prevalence and intervention data. We estimated the fraction of HIV infections averted by the interventions, and the fraction of incident infections acquired and transmitted by different populations over successive 10-year periods (1976-2015). RESULTS:Overall, condom use averted 61% (95% credible intervals: 56%-66%) of all adult infections during 1987-2015 mainly because of increased use by FSW (46% of infections averted). In comparison, ART prevented 15% (10%-19%) of adult infections during 2010-2015. As a result, FSW initially (1976-1985) contributed 95% (91%-97%) of all new infections, declining to 19% (11%-27%) during 2005-2015. Older men and clients mixing with non-FSW are currently the highest contributors to transmission. Men who have sex with men contributed ?4% transmissions throughout. Young women (15-24 years; excluding FSW) do not transmit more infections than they acquired. CONCLUSIONS:Early increases in condom use, mainly by FSW, have substantially reduced HIV transmission. Clients of FSWs and older men have become the main source of transmission, whereas young women remain at increased risk. Strengthening prevention and scaling-up of ART, particularly to FSW and clients of female sex workers, is important.
Project description:<h4>Introduction</h4>In Bangalore, new HIV infections of female sex workers and men who have sex with men continue to occur, despite high condom use. Pre-exposure prophylaxis (PrEP) has high anti-HIV efficacy for men who have sex with men. PrEP demonstration projects are underway amongst Indian female sex workers. We estimated the impact and efficiency of prioritizing PrEP to female sex workers and/or men who have sex with men in Bangalore.<h4>Methods</h4>A mathematical model of HIV transmission and treatment for female sex workers, clients, men who have sex with men and low-risk groups was parameterized and fitted to Bangalore data. The proportion of transmission attributable (population attributable fraction) to commercial sex and sex between men was calculated. PrEP impact (infections averted, life-years gained) and efficiency (life-years gained/infections averted per 100 person-years on PrEP) were estimated for different levels of PrEP adherence, coverage and prioritization strategies (female sex workers, high-risk men who have sex with men, both female sex workers and high-risk men who have sex with men, or female sex workers with lower condom use), under current conditions and in a scenario with lower baseline condom use amongst key populations.<h4>Results</h4>Population attributable fractions for commercial sex and sex between men have declined over time, and they are predicted to account for 19% of all new infections between 2016 and 2025. PrEP could prevent a substantial proportion of infections amongst female sex workers and men who have sex with men in this setting (23%/27% over 5/10 years, with 60% coverage and 50% adherence), which could avert 2.9%/4.3% of infections over 5/10 years in the whole Bangalore population. Impact and efficiency in the whole population was greater if female sex workers were prioritized. Efficiency increased, but impact decreased, if only female sex workers with lower condom use were given PrEP. Greater impact and efficiency was predicted for the scenario with lower condom use.<h4>Conclusions</h4>PrEP could be beneficial for female sex workers and men who have sex with men in Bangalore, and give some benefits in the general population, especially in similar settings with lower condom use levels.
Project description:OBJECTIVE:To describe and compare trends in prevalence, sexual behaviour and HIV transmission knowledge data related to sexually transmitted infections (STI) and HIV in patients attending three STI clinics over an 8-year period in Escuintla Department, Guatemala. METHODS:STI clinic attendees were classified into transmission groups as follows: female sex workers (FSW), men who have sex with men (MSM) and 'high-risk heterosexuals' (HRH). Annual cross-sectional analysis and multivariable Poisson regression adjusted for sociodemographic variables were used for prevalence comparisons and adjusted prevalence trends for HIV/STI outcomes and used for adjusted trends in proportions in sexual behaviour and HIV transmission knowledge outcomes. Endocervical swabs were obtained to detect trichomonas, chlamydia and neisseria infections. Serologies for syphilis and HIV were performed using rapid tests. For reactive HIV samples, positivity was confirmed by an ELISA. All reactive syphilis samples were further confirmed for diagnosis of active syphilis disease. RESULTS:From a total of 4027 clinic attendees, 3213 (79.78%) were FSW, 229 (5.69%) were MSM and 585 (14.53%) were HRH. The proportion of FSW, MSM and HRH who had a single visit was 56.42%, 57.23% and 91.10%, respectively. Overall, HIV prevalence was 2.10% in FSW, 8.17% in MSM and 4.12% in HRH. Prevalence trends in HIV and syphilis decreased in FSW. Prevalence trends in gonorrhoea did not decrease over time neither in FSW nor in HRH. Chlamydia and trichomonas infections in HRH showed an increase prevalence trend. In FSW, trends in condom use in last sexual intercourse with regular and occasional clients were above 93%. CONCLUSIONS:FSW show a decreasing trend in HIV, syphilis and chlamydia prevalence. Gonorrhoea prevalence in FSW and HRH did not decrease over time. HRH is a hard to engage population with low follow-up rates and high potential to act as a bridge population.
Project description:<h4>Purpose</h4>We examined condom use patterns and potential population-level effects of a hypothetical condom intervention on HIV transmission among adolescent sexual minority males (ASMM).<h4>Methods</h4>Using three datasets: national Youth Risk Behavior Survey 2015-2017 (YRBS-National), local YRBS data from 8 jurisdictions with sex of partner questions from 2011-2017 (YRBS-Trends), and American Men's Internet Survey (AMIS) 2014-2017, we assessed associations of condom use with year, age, and race/ethnicity among sexually-active ASMM. Using a stochastic agent-based network epidemic model, structured and parameterized based on the above analyses, we calculated the percent of HIV infections averted over 10 years among ASMM ages 13-18 by an intervention that increased condom use by 37% for 5 years and was delivered to 62% of ASMM at age 14.<h4>Results</h4>In YRBS, 51.8% (95% confidence interval [CI] = 41.3-62.3%) and 37.9% (32.7-42.3%) reported condom use at last sexual intercourse in national and trend datasets, respectively. In AMIS, 47.3% (95%CI = 44.6-49.9%) reported condom use at last anal sex with a male partner. Temporal trends were not observed in any dataset (p > 0.1). Condom use varied significantly by age in YRBS-National (p < 0.0001) and YRBS-Trends (p = 0.032) with 13-15-year-olds reporting the lowest use in both; age differences were not significant in AMIS (p = 0.919). Our hypothetical intervention averted a mean of 9.0% (95% simulation interval = -5.4%-21.2%) of infections among ASMM.<h4>Conclusions</h4>Condom use among ASMM is low and appears to have remained stable during 2011-2017. Modeling suggests that condom use increases consistent with previous interventions have potential to avert 1 in 11 new HIV infections among ASMM.
Project description:BACKGROUND:Bacterial sexually transmitted infections may facilitate HIV transmission. Bacterial sexually transmitted infection testing is recommended for sexually active HIV-infected patients annually and more frequently for those at elevated sexual risk. We estimated percentages of HIV-infected patients in the United States receiving at least one syphilis, gonorrhea, or chlamydia test, and repeat (?2 tests, ?3 months apart) tests for any of these sexually transmitted infections from mid-2008 through mid-2010. DESIGN:The Medical Monitoring Project collects behavioral and clinical characteristics of HIV-infected adults receiving medical care in the United States using nationally representative sampling. METHODS:Sexual activity included self-reported oral, vaginal, or anal sex in the past 12 months. Participants reporting more than 1 sexual partner or illicit drug use before/during sex in the past year were classified as having elevated sexual risk. Among participants with only 1 sex partner and no drug use before/during sex, those reporting consistent condom use were classified as low risk; those reporting sex without a condom (or for whom this was unknown) were classified as at elevated sexual risk only if they considered their sex partner to be a casual partner, or if their partner was HIV-negative or partner HIV status was unknown. Bacterial sexually transmitted infection testing was ascertained through medical record abstraction. RESULTS:Among sexually active patients, 55% were tested at least once in 12 months for syphilis, whereas 23% and 24% received at least one gonorrhea and chlamydia test, respectively. Syphilis testing did not vary by sex/sexual orientation. Receipt of at least 3 CD4+ T-lymphocyte cell counts and/or HIV viral load tests in 12 months was associated with syphilis testing in men who have sex with men (MSM), men who have sex with women only, and women. Chlamydia testing was significantly higher in sexually active women (30%) compared with men who have sex with women only (19%), but not compared with MSM (22%). Forty-six percent of MSM were at elevated sexual risk; 26% of these MSM received repeat syphilis testing, whereas repeat testing for gonorrhea and chlamydia was only 7% for each infection. CONCLUSIONS:Bacterial sexually transmitted infection testing among sexually active HIV-infected patients was low, particularly for those at elevated sexual risk. Patient encounters in which CD4+ T-lymphocyte cell counts and/or HIV viral load testing occurs present opportunities for increased bacterial sexually transmitted infection testing.
Project description:BACKGROUND: Advances in communication technology may affect networking pattern, thereby influencing the dynamics of sex partnership. The aim of the study is to explore the impacts of partner sourcing through internet and related channels on exposure risk to sexually transmitted infections (STI) including HIV. METHODS: Using venue-based sampling, a cross-sectional questionnaire survey was conducted at saunas frequented by men having sex with men (MSM) in Hong Kong. Comparison was made between MSM sourcing partners through physical venues alone versus concomitant users of physical and virtual channels, the latter referring to internet and smart-phone applications, using bivariate logistic regression. RESULTS: Over a 7-week study period, 299 MSM were recruited from 9 saunas. Three main types of sex partners were distinguished: steady (46.8%), regular (26.4%) and casual (96.0%) partners. Users of sauna (n = 78) were compared with concomitant users of saunas and virtual channels (n = 179) for partner sourcing. Sauna-visiting virtual channel users were younger and inclined to use selected physical venues for sourcing partners. Smart-phone users (n = 90) were not different from other internet-users in terms of age, education level and single/mixed self-identified body appearance. Classifying respondents into high risk and low risk MSM by their frequency of condom use, concomitant use of both sauna and virtual channels accounted for a higher proportion in the high risk category (71.6% vs. 58.2%, OR = 1.81, p<0.05). In virtual channel users, partner sourcing through smart-phone was not associated with a higher practice of unprotected sex. CONCLUSION: MSM sauna customers commonly use virtual channels for sex partner sourcing. Unprotected sex is more prevalent in sauna customers who use virtual channel for sex partner sourcing. While the popularity of smart-phone is rising, its use is not associated with increased behavioural risk for HIV/STI transmission.
Project description:<h4>Objectives</h4>Young people are a critical target group for sexually transmitted infections (STI) surveillance due to their particular behavioural and social related vulnerability. The aim of this study was to describe the epidemiological characteristics and trends in the incidence of gonorrhoea, syphilis, HIV and venereal lymphogranuloma (LGV) among 15-24-year-olds in Barcelona, and to determine factors associated with HIV coinfection.<h4>Design</h4>We performed a population-based incidence study covering the 2007-2015 period.<h4>Participants</h4>All new cases of STI-HIV, gonorrhoea, infectious syphilis and LGV-notified to the epidemiological surveillance system in Barcelona between 2007 and 2015. 1218 cases were studied: 84.6% were men, 19.3% were 15-19 years old and 50.6% were born in Spain. Among men, 73.7% were men who have sex with men (MSM); among women, 85.6% were women that have sex with men.<h4>Primary and secondary outcomes</h4>Incidence of HIV, gonorrhoea, infectious syphilis and LGV. HIV coinfection.<h4>Results</h4>There was an increase in the incidence of gonorrhoea, from 1.9 cases per 10?000 people in 2007 to 7.6/10 000 in 2015 (p<0.01), in MSM from 27.1 to 228.8/10 000 (p<0.01). The incidence of syphilis increased from 0.4/10 000 in 2007 to 3.1/10 000 in 2015 (significant in men only, p<0.01), in MSM from 18.1 to 116.9/10 000 (p<0.01). The incidence of HIV showed a non-significant increase in men (p=0.27), and that of LGV remained stable (p=0.59). Factors associated with increased risk of HIV coinfection included being MSM (adjusted OR[ORa]=14.14, 95% CI 3.34 to 59.91) and having >10?sexual partners (ORa=4.11, 95% CI 1.53 to 11.01) or STI diagnosis during the previous 12 months (ORa=2.06; 95% CI 1.13 to 3.77).<h4>Conclusions</h4>The incidence of gonorrhoea and syphilis among 15-24-year-olds increased, while HIV infection remained stable but with a high incidence among MSM. Being MSM, having sex with multiple partners and having a diagnosis of an STI in the previous 12 months were factors associated with HIV coinfection.
Project description:<h4>Background</h4>Information on cost-effectiveness of the range of HIV prevention interventions is a useful contributor to decisions on the best use of resources to prevent HIV. We conducted this assessment for the state of Andhra Pradesh that has the highest HIV burden in India.<h4>Methods</h4>Based on data from a representative sample of 128 public-funded HIV prevention programs of 14 types in Andhra Pradesh, we have recently reported the number of HIV infections averted by each type of HIV prevention intervention and their cost. Using estimates of the age of onset of HIV infection, we used standard methods to calculate the cost per Disability Adjusted Life Year (DALY) saved as a measure of cost-effectiveness of each type of HIV prevention intervention.<h4>Results</h4>The point estimates of the cost per DALY saved were less than US $50 for blood banks, men who have sex with men programmes, voluntary counselling and testing centres, prevention of parent to child transmission clinics, sexually transmitted infection clinics, and women sex worker programmes; between US $50 and 100 for truckers and migrant labourer programmes; more than US $100 and up to US $410 for composite, street children, condom promotion, prisoners and workplace programmes and mass media campaign for the general public. The uncertainty range around these estimates was very wide for several interventions, with the ratio of the high to the low estimates infinite for five interventions.<h4>Conclusions</h4>The point estimates for the cost per DALY saved from the averted HIV infections for all interventions was much lower than the per capita gross domestic product in this Indian state. While these indicative cost-effectiveness estimates can inform HIV control planning currently, the wide uncertainty range around estimates for several interventions suggest the need for more firm data for estimating cost-effectiveness of HIV prevention interventions in India.