Peter Vickerman

University of Bristol, Bristol, England, United Kingdom

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Publications (170)879.01 Total impact

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    ABSTRACT: Hepatitis C virus (HCV) elimination is being seriously considered globally. Current elimination models require a combination of highly effective HCV treatment and harm reduction, but high treatment costs make such strategies prohibitively expensive. Vaccines should play a key role in elimination but their best use alongside treatments is unclear. For three vaccines with different efficacies we used a mathematical model to estimate the additional reduction in HCV prevalence when vaccinating after treatment; and to identify in which settings vaccines could most effectively reduce the number of treatments required to achieve fixed reductions in HCV prevalence among people who inject drugs (PWID). A deterministic model of HCV transmission among PWID was calibrated for settings with 25, 50 and 75 % chronic HCV prevalence among PWID, stratified by high-risk or low-risk PWID. For vaccines with 30, 60 or 90 % efficacies, different rates of treatment and vaccination were introduced. We compared prevalence reductions achieved by vaccinating after treatment to prevent reinfection and vaccinating independently of treatment history in the community; and by allocating treatments and vaccinations to specific risk groups and proportionally across risk groups. Vaccinating after treatment was minimally different to vaccinating independently of treatment history, and allocating treatments and vaccinations to specific risk groups was minimally different to allocating them proportionally across risk groups. Vaccines with 30 or 60 % efficacy provided greater additional prevalence reduction per vaccination in a setting with 75 % chronic HCV prevalence among PWID than a 90 % efficacious vaccine in settings with 25 or 50 % chronic HCV prevalence among PWID. Vaccinating after treatment is an effective and practical method of administration. In settings with high chronic HCV prevalence among PWID, even modest coverage with a low-efficacy vaccine could provide significant additional prevalence reduction beyond treatment alone, and would likely reduce the cost of achieving prevalence reduction targets.
    BMC Medicine 12/2015; 13(1):198. DOI:10.1186/s12916-015-0440-2 · 7.25 Impact Factor
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    ABSTRACT: Objectives: The objective of this study is to understand the association between HIV and hepatitis C virus (HCV) among people who inject drugs (PWIDs) in the Middle East and North Africa (MENA), and to estimate HIV epidemic potential among PWIDs using HCV prevalence. Design/methods: Using data from a systematic review of HIV and HCV among PWID in MENA, we conducted two analyses, stratified by HIV epidemic state: a meta-analysis of the risk ratio of HCV to HIV prevalence (RRHCV/HIV) using DerSimonian-Laird random-effects models, and multivariable linear regression predicting log HIV prevalence. The HCV-HIV association from both analyses was used to estimate HIV prevalence at endemic equilibrium. We compared predicted with current HIV prevalence to classify HIV epidemic potential at country-level as low, medium or high, using predefined criteria. Results: The review identified 88 HCV prevalence measures among PWID in MENA, of which 54 had a paired HIV prevalence measure. The pooled RRHCV/HIV were 16, 4 and 3 in low-level, emerging and established HIV epidemics, respectively. There was a significant linear relationship between HCV and HIV at endemic equilibrium (P = 0.002). The predicted endemic HIV prevalence ranged between 8% (Tunisia) and 22% (Pakistan). Of the nine countries with data, five have high and three medium HIV epidemic potential. Only one country, Pakistan, appears to have reached saturation. Conclusion: HCV prevalence could be a predictor of future endemic HIV prevalence. In MENA, we predict that there will be further HIV epidemic growth among PWID. The proposed methodology can identify PWID populations that should be prioritized for HIV prevention interventions.
    AIDS (London, England) 09/2015; 29(13):1701-10. DOI:10.1097/QAD.0000000000000761 · 5.55 Impact Factor
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    ABSTRACT: Objective: To estimate the impact and cost-effectiveness of treatment as prevention (TasP), pre-exposure prophylaxis (PrEP) and condom promotion for serodiscordant couples in Nigeria. Design: Mathematical and cost modelling. Methods: A deterministic model of HIV-1 transmission within a cohort of serodiscordant couples and to/from external partners was parameterized using data from Nigeria and other African settings. The impact and cost-effectiveness were estimated for condom promotion, PrEP and/or TasP, compared with a baseline where antiretroviral therapy (ART) was offered according to 2010 national guidelines (CD4 <350 cells/μl) to all HIV-positive partners. The impact was additionally compared with a baseline of current ART coverage (35% of those with CD4 <350 cells/μl). Full costs (in US $2012) of programme introduction and implementation were estimated from a provider perspective. Results: Substantial benefits came from scaling up ART to all HIV-positive partners according to 2010 national guidelines, with additional smaller benefits of providing TasP, PrEP or condom promotion. Compared with a baseline of offering ART to all HIV-positive partners at the 2010 national guidelines, condom promotion was the most cost-effective strategy [US $1206/disability-adjusted-life-year (DALY)], the next most cost-effective intervention was to additionally give TasP to HIV-positive partners (incremental cost-effectiveness ratio US $1607/DALY), followed by additionally giving PrEP to HIV-negative partners until their HIV-positive partners initiate ART (US $7870/DALY). When impact was measured in terms of infections averted, PrEP with condom promotion prevented double the number of infections as condom promotion alone. Conclusions: The first priority intervention for serodiscordant couples in Nigeria should be scaled up ART access for HIV-positive partners. Subsequent incremental benefits are greatest with condom promotion and TasP, followed by PrEP.
    AIDS (London, England) 09/2015; 29(15):2035-44. DOI:10.1097/QAD.0000000000000798 · 5.55 Impact Factor
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    ABSTRACT: The burden of hepatitis C virus (HCV) is high among people who inject drugs (PWID) and prisoners, and increasing among HIV-infected MSM, who are key populations for HCV transmission in high-income countries and may also play a role in many in low- and middle-income countries. There is an increasing interest in the use of HCV antiviral treatment for prevention in these populations. Numerous theoretical modelling studies have explored the potential impact of HCV treatment for prevention among PWID in a range of global settings, generally finding that modest and achievable levels of HCV treatment, especially with interferon-free direct-acting antiviral therapy (IFN-free DAAs), could substantially reduce HCV chronic prevalence among PWID within the next 10-20 years. In addition, modelling studies have shown HCV testing and treatment in prison (including prevention benefits) could be cost-effective if continuity of care is ensured, or HCV treatments are shortened with DAAs. Modelling work among HIV-infected MSM has shown that further HCV treatment scale-up is likely required despite high treatment rates in this population. However, no empirical studies have explored whether HCV treatment can reduce HCV prevalence and prevent onwards transmission among those at risk of transmission. HCV treatment for key populations such as PWID, prisoners and MSM could become an important HCV prevention intervention, especially in the IFN-free DAA era. However, there is an urgent need to test these hypotheses through empirical studies.
    Current opinion in HIV and AIDS 09/2015; 10(5):374-80. DOI:10.1097/COH.0000000000000179 · 4.68 Impact Factor
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    ABSTRACT: HIV impacts heavily on the operating costs of companies in sub-Saharan Africa, with many companies now providing antiretroviral therapy (ART) programmes in the workplace. A full cost-benefit analysis of workplace ART provision has not been conducted using primary data. We developed a dynamic health-state transition model to estimate the economic impact of HIV and the cost-benefit of ART provision in a mining company in South Africa between 2003 and 2022. A dynamic health-state transition model, called the Workplace Impact Model (WIM), was parameterised with workplace data on workforce size, composition, turnover, HIV incidence, and CD4 cell count development. Bottom-up cost analyses from the employer perspective supplied data on inpatient and outpatient resource utilisation and the costs of absenteeism and replacement of sick workers. The model was fitted to workforce HIV prevalence and separation data while incorporating parameter uncertainty; univariate sensitivity analyses were used to assess the robustness of the model findings. As ART coverage increases from 10% to 97% of eligible employees, increases in survival and retention of HIV-positive employees and associated reductions in absenteeism and benefit payments lead to cost savings compared to a scenario of no treatment provision, with the annual cost of HIV to the company decreasing by 5% (90% credibility interval [CrI] 2%-8%) and the mean cost per HIV-positive employee decreasing by 14% (90% CrI 7%-19%) by 2022. This translates into an average saving of US$950,215 (90% CrI US$220,879-US$1.6 million) per year; 80% of these cost savings are due to reductions in benefit payments and inpatient care costs. Although findings are sensitive to assumptions regarding incidence and absenteeism, ART is cost-saving under considerable parameter uncertainty and in all tested scenarios, including when prevalence is reduced to 1%-except when no benefits were paid out to employees leaving the workforce and when absenteeism rates were half of what data suggested. Scaling up ART further through a universal test and treat strategy doubles savings; incorporating ART for family members reduces savings but is still marginally cost-saving compared to no treatment. Our analysis was limited to the direct cost of HIV to companies and did not examine the impact of HIV prevention policies on the miners or their families, and a few model inputs were based on limited data, though in sensitivity analysis our results were found to be robust to changes to these inputs along plausible ranges. Workplace ART provision can be cost-saving for companies in high HIV prevalence settings due to reductions in healthcare costs, absenteeism, and staff turnover. Company-sponsored HIV counselling and voluntary testing with ensuing treatment of all HIV-positive employees and family members should be implemented universally at workplaces in countries with high HIV prevalence.
    PLoS Medicine 09/2015; 12(9). DOI:10.1371/journal.pmed.1001869 · 14.43 Impact Factor
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    ABSTRACT: Evaluation of large-scale intervention programmes against human immunodeficiency virus (HIV) is becoming increasingly important, but impact estimates frequently hinge on knowledge of changes in behaviour such as the frequency of condom use over time, or other self-reported behaviour changes, for which we generally have limited or potentially biased data. We employ a Bayesian inference methodology that incorporates an HIV transmission dynamics model to estimate condom use time trends from HIV prevalence data. Estimation is implemented via particle Markov chain Monte Carlo methods, applied for the first time in this context. The preliminary choice of the formulation for the time varying parameter reflecting the proportion of condom use is critical in the context studied, because of the very limited amount of condom use and HIV data available. We consider various novel formulations to explore the trajectory of condom use over time, based on diffusion-driven trajectories and smooth sigmoid curves. Numerical simulations indicate that informative results can be obtained regarding the amplitude of the increase in condom use during an intervention, with good levels of sensitivity and specificity performance in effectively detecting changes. The application of this method to a real life problem demonstrates how it can help in evaluating HIV interventions based on a small number of prevalence estimates, and it opens the way to similar applications in different contexts.
    Journal of the Royal Statistical Society Series C Applied Statistics 08/2015; DOI:10.1111/rssc.12116 · 1.49 Impact Factor
  • Matthew Hickman · Peter Vickerman · Louisa Degenhardt
    Clinical Infectious Diseases 06/2015; 61(7). DOI:10.1093/cid/civ481 · 8.89 Impact Factor
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    ABSTRACT: Rapid plasma reagin (RPR) is frequently used to test women for maternal syphilis. Rapid syphilis immunochromatographic strip tests detecting only Treponema pallidum antibodies (single RSTs) or both treponemal and non-treponemal antibodies (dual RSTs) are now available. This study assessed the cost-effectiveness of algorithms using these tests to screen pregnant women. Observed costs of maternal syphilis screening and treatment using clinic-based RPR and single RSTs in 20 clinics across Peru, Tanzania, and Zambia were used to model the cost-effectiveness of algorithms using combinations of RPR, single, and dual RSTs, and no and mass treatment. Sensitivity analyses determined drivers of key results. Although this analysis found screening using RPR to be relatively cheap, most (>70%) true cases went untreated. Algorithms using single RSTs were the most cost-effective in all observed settings, followed by dual RSTs, which became the most cost-effective if dual RST costs were halved. Single test algorithms dominated most sequential testing algorithms, although sequential algorithms reduced overtreatment. Mass treatment was relatively cheap and effective in the absence of screening supplies, though treated many uninfected women. This analysis highlights the advantages of introducing RSTs in three diverse settings. The results should be applicable to other similar settings. Copyright © 2015 International Federation of Gynecology and Obstetrics. All rights reserved.
    International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics 04/2015; 91. DOI:10.1016/j.ijgo.2015.04.007 · 1.54 Impact Factor
  • H. Woodall · N. Martin · T. Hallett · G. Cooke · M. Hickman · P. Vickerman
    Journal of Hepatology 04/2015; 62:S839-S840. DOI:10.1016/S0168-8278(15)31477-X · 11.34 Impact Factor
  • Journal of Hepatology 04/2015; 62:S255-S256. DOI:10.1016/S0168-8278(15)30143-4 · 11.34 Impact Factor
  • Journal of Hepatology 04/2015; 62:S835. DOI:10.1016/S0168-8278(15)31466-5 · 11.34 Impact Factor
  • Journal of Hepatology 04/2015; 62:S843. DOI:10.1016/S0168-8278(15)31484-7 · 11.34 Impact Factor
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    ABSTRACT: Promoted globally as an evidence-based intervention in the prevention of HIV and treatment of heroin addiction among people who inject drugs (PWID), opioid substitution treatment (OST) can help control emerging HIV epidemics among PWID. With implementation in December 2014, Kenya is the third Sub-Saharan African country to have introduced OST. We combine dynamic mathematical modelling with qualitative sociological research to examine the 'promise of methadone' to Kenya. We model the HIV prevention impact of OST in Nairobi, Kenya, at different levels of intervention coverage. We draw on thematic analyses of 109 qualitative interviews with PWID, and 43 with stakeholders, to chart their narratives of expectation in relation to the promise of methadone. The modelled impact of OST shows relatively slight reductions in HIV incidence (5-10%) and prevalence (2-4%) over 5 years at coverage levels (around 10%) anticipated in the planned roll-out of OST. However, there is a higher impact with increased coverage, with 40% coverage producing a 20% reduction in HIV incidence, even when accounting for relatively high sexual transmissions. Qualitative findings emphasise a culture of 'rationed expectation' in relation to access to care and a 'poverty of drug treatment opportunity'. In this context, the promise of methadone may be narrated as a symbol of hope-both for individuals and community-in relation to addiction recovery. Methadone offers HIV prevention potential, but there is a need to better model the effects of sexual HIV transmission in mediating the impact of OST among PWID in settings characterised by a combination of generalised and concentrated epidemics. We find that individual and community narratives of methadone as hope for recovery coexist with policy narratives positioning methadone primarily in relation to HIV prevention. Our analyses show the value of mixed methods approaches to investigating newly-introduced interventions. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to
    BMJ Open 03/2015; 5(3). DOI:10.1136/bmjopen-2014-007198 · 2.27 Impact Factor
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    ABSTRACT: Hepatitis C virus (HCV) reinfection rates are probably underestimated due to reinfection episodes occurring between study visits. A Markov model of HCV reinfection and spontaneous clearance was fitted to empirical data. Bayesian post-estimation was used to project reinfection rates, reinfection spontaneous clearance probability and duration of reinfection. Uniform prior probability distributions were assumed for reinfection rate (more than 0), spontaneous clearance probability (0-1) and duration (0.25-6.00 months). Model estimates were 104 per 100 person-years (95% CrI: 21-344), 0.84 (95% CrI: 0.59-0.98) and 1.3 months (95% CrI: 0.3-4.1) for reinfection rate, spontaneous clearance probability and duration, respectively. Simulation studies were used to assess model validity, demonstrating that the Bayesian model estimates provided useful information about the possible sources and magnitude of bias in epidemiological estimates of reinfection rates, probability of reinfection clearance and duration or reinfection. The quality of the Bayesian estimates improved for larger samples and shorter test intervals. Uncertainty in model estimates notwithstanding, findings suggest that HCV reinfections frequently and quickly result in spontaneous clearance, with many reinfection events going unobserved. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
    Journal of The Royal Society Interface 03/2015; 12(104). DOI:10.1098/rsif.2014.1197 · 3.92 Impact Factor
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    ABSTRACT: The impact and cost-effectiveness of antiretroviral treatment (ART) as prevention is likely to vary depending on the local context. Burkina Faso has a concentrated mature HIV epidemic where female sex workers (FSW) are thought to have driven HIV transmission. A dynamic HIV transmission model was developed using data from the Yerelon FSW cohort in Bobo-Dioulasso and population surveys. Compared with current ART provision [status quo (SQ)], the model estimated the proportion of HIV infections averted or incremental life-years gained per additional person-year of ART over 20 years for ART targeting different subgroups or expanding eligibility to all HIV-infected individuals compared with SQ. Modeling suggests that condom use within commercial sex has averted 40% of past HIV infections. Continuing SQ averts 35%-47% of new infections over 20 years compared with no ART. Expanding ART eligibility to all HIV-infected individuals and increasing recruitment (80% per year) could avert a further 65% of new infections, whereas targeting full-time FSW or all FSWs achieved less impact but was more efficient in terms of life-years gained per 100 person-years of ART. Local HIV elimination is possible with expanded ART provision to FSWs but requires condom use within commercial sex to be maintained at high levels. Increasing FSW recruitment onto ART could be a highly efficient method for reducing HIV transmission in concentrated epidemic settings but should not be undertaken at the expense of existing interventions for FSWs. Specialized clinics providing multiple interventions for FSWs should be a fundamental component of prevention in concentrated epidemics.
    JAIDS Journal of Acquired Immune Deficiency Syndromes 03/2015; 68 Suppl 2:S180-S188. DOI:10.1097/QAI.0000000000000441 · 4.56 Impact Factor
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    ABSTRACT: HIV epidemics have traditionally been classified as "concentrated" among key populations if overall HIV prevalence was below 1% and as "generalized" otherwise. We aimed to objectively determine the utility of this classification by determining how high overall HIV prevalence can reach in epidemics driven by unprotected sex work (SW) and how estimates of the contribution of SW to HIV transmission changes over time in these epidemics. We developed a deterministic model of HIV transmission specific to West and Central Africa to simulate 1000 synthetic HIV epidemics, where SW is the sole behavioral driver that sustains HIV in the population (ie, truly concentrated epidemics), and it is based on a systematic extraction of model parameters specific to West and Central Africa. We determined the range of plausible HIV prevalence in the total population over time and calculated the population attributable fraction (PAF) of SW over different time periods. In 1988 and 2008, HIV prevalence across the 1000 synthetic concentrated HIV epidemics ranged (5th-95th percentile) between 0.1%-4.2% and 0.1%-2.8%, respectively. The maximum HIV prevalence peaked at 12%. The PAF of SW measured from 2008 over 1 year was <5%-18% compared with 16%-59% over 20 years in these SW-driven epidemics. Even high HIV-prevalence epidemics can be driven by unprotected SW and therefore concentrated. Overall, HIV prevalence and the short-term PAF are poor makers of underlying transmission dynamics and underestimate the role of SW in HIV epidemics and thus should not be used alone to inform HIV programs.
    JAIDS Journal of Acquired Immune Deficiency Syndromes 03/2015; 68 Suppl 2:S74-S82. DOI:10.1097/QAI.0000000000000437 · 4.56 Impact Factor
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    ABSTRACT: Herpes simplex virus type 2 (HSV-2) infection causes significant disease globally. Adolescent and adult infection may present as painful genital ulcers. Neonatal infection has high morbidity and mortality. Additionally, HSV-2 likely contributes substantially to the spread of HIV infection. The global burden of HSV-2 infection was last estimated for 2003. Here we present new global estimates for 2012 of the burden of prevalent (existing) and incident (new) HSV-2 infection among females and males aged 15-49 years, using updated methodology to adjust for test performance and estimate by World Health Organization (WHO) region. We conducted a literature review of HSV-2 prevalence studies world-wide since 2000. We then fitted a model with constant HSV-2 incidence by age to pooled HSV-2 prevalence values by age and sex. Prevalence values were adjusted for test sensitivity and specificity. The model estimated prevalence and incidence by sex for each WHO region to obtain global burden estimates. Uncertainty bounds were computed by refitting the model to reflect the variation in the underlying prevalence data. In 2012, we estimate that there were 417 million people aged 15-49 years (range: 274-678 million) living with HSV-2 infection world-wide (11.3% global prevalence), of whom 267 million were women. We also estimate that in 2012, 19.2 million (range: 13.0-28.6 million) individuals aged 15-49 years were newly-infected (0.5% of all individuals globally). The highest burden was in Africa. However, despite lower prevalence, South-East Asia and Western Pacific regions also contributed large numbers to the global totals because of large population sizes. The global burden of HSV-2 infection is large, leaving over 400 million people at increased risk of genital ulcer disease, HIV acquisition, and transmission of HSV-2 to partners or neonates. These estimates highlight the critical need for development of vaccines, microbicides, and other new HSV prevention strategies.
    PLoS ONE 01/2015; 10(1):e114989. DOI:10.1371/journal.pone.0114989 · 3.23 Impact Factor
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    ABSTRACT: AimsTo systematically assess risk of HIV acquisition by type of drug injected across different settings.MethodsA systematic review and meta-analysis were conducted. Databases were searched for studies of HIV incidence in people who inject different drugs (PWID). Pooled HIV incidence rate ratio (IRR) was used to compare HIV risk between injecting a given drug and not-injecting, when possible, or with those reported not to have injected the substance, otherwise. Pooled estimates of crude IRR were derived using random effects models. Variations in IRR were assessed in sub-group analyses, by drug and geographical region.ResultsOf 5779 studies screened, 15 were included. HIV incidence was reported for people injecting cocaine (8,North-America, Europe), amphetamine-type stimulants (ATS) (4,West- and Eastern-Europe, Asia), heroin (11,all settings), opiates-stimulants (4,North America, West-,Eastern-Europe) and opiates-sedatives (5, Europe, Asia). HIV risk in cocaine injectors was 3.6 times (95%CI: 2.8-4.7, I2=0%;N=4) that of non-injectors and 3.0 for ATS injectors (95%CI: 2.2-4.1, I2=0%;N=2). Higher sexual risk was reported in cohorts injecting stimulants. Compared to not-injecting, HIV IRR was 2.8 (95%CI: 1.7-4.7, I2=77%;N=6) for all heroin injectors and 3.5 (95%CI: 2.3-5.2, I2=40%;N=5) for heroin injectors in Asia and Europe.Conclusion The risk of HIV acquisition in people who inject drugs appears to vary by drug type but differences are not statistically significant, precluding conclusive grading of risk. This article is protected by copyright. All rights reserved.
    Addiction 01/2015; 110(4). DOI:10.1111/add.12846 · 4.74 Impact Factor
  • Hepatology 01/2015; 61(1). DOI:10.1002/hep.27194 · 11.06 Impact Factor
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    ABSTRACT: The Avahan intervention promotes consistent (100%) condom use amongst men who have sex with men in southern India. We assessed how condom use varies with intervention exposure for men who have sex with men in Bangalore. Self-reported condom use and intervention exposure data were derived from a cross-sectional survey. Consistent condom use and condom use at last sex act with all, main, and casual male sex partners were assessed. Binary and continuous variables reflecting intervention exposure (including contact(s) with intervention staff, receiving condoms and seeing condom demonstrations) were used. Multivariable logistic regression was employed to assess the relationship between condom use with each type of partner and each exposure variable independently, controlling for socio-demographic and behavioural factors associated with condom use or intervention exposure. Condom use with all partners was higher among those who had ever been contacted by, received condoms from, or seen a condom demonstration by intervention staff (adjusted odds ratio >2, p < 0.02 for all). Consistent condom use with all types of partner increased with the number of condom demonstrations seen in the last month (adjusted odds ratio = 2.1 per demonstration, p < 0.025), while condom use at last sex act with a casual (but not main) partner increased with the number of condoms received from the intervention (adjusted odds ratio = 1.4 per condom, p = 0.04). Direct contact with Avahan program staff is associated with increased reported condom use among men who have sex with men in Bangalore. Reported consistent condom use and condom use at last sex act are associated with contacts involving demonstrations of correct condom use, and with receiving condoms, respectively.
    BMC Public Health 12/2014; 14(1):1245. DOI:10.1186/1471-2458-14-1245 · 2.26 Impact Factor

Publication Stats

2k Citations
879.01 Total Impact Points


  • 2009–2015
    • University of Bristol
      • School of Social and Community Medicine
      Bristol, England, United Kingdom
    • University of British Columbia - Vancouver
      • School of Population and Public Health
      Vancouver, British Columbia, Canada
  • 2002–2015
    • London School of Hygiene and Tropical Medicine
      • • Centre for Research on Drugs and Health Behaviour (CRDHB)
      • • Department of Infectious Disease Epidemiology
      • • Department of Global Health and Development
      Londinium, England, United Kingdom
  • 2013
    • University of London
      • The London School of Hygiene and Tropical Medicine
      Londinium, England, United Kingdom
  • 2012
    • Burnet Institute
      • Centre for Population Health
      Melbourne, Victoria, Australia
  • 2007
    • International Centre for Diarrhoeal Disease Research, Bangladesh
      Mujib City, Dhaka, Bangladesh
  • 2006
    • PATH
      Seattle, Washington, United States
  • 2003
    • Laval University
      • Department of Social and Preventive Medicine
      Quebec City, Quebec, Canada