216 results found
Vickerman P, Pickles M, Lowndes CM, et al., 2011, IMPACT OF THE AVAHAN INTERVENTION ON HIV/STI TRANSMISSION AMONGST HIGH AND LOW-RISK GROUPS: AN INTERIM MODELLING ASSESSMENT, SEXUALLY TRANSMITTED INFECTIONS, Vol: 87, Pages: A8-A9, ISSN: 1368-4973
Boily MC, 2011, THE RELATIVE CONTRIBUTION OF ANAL INTERCOURSE AND PRIMARY INFECTION TO MATURE HETEROSEXUAL HIV EPIDEMICS, SEXUALLY TRANSMITTED INFECTIONS, Vol: 87, Pages: A38-A38, ISSN: 1368-4973
Dureau J, Boily MC, Vickerman P, et al., 2011, WHAT HAS BEEN THE EFFECT OF THE AVAHAN HIV INTERVENTION ON CONDOM USE AMONG FEMALE SEX WORKERS? INSIGHTS FROM A FULLY BAYESIAN INFERENCE METHODOLOGY, SEXUALLY TRANSMITTED INFECTIONS, Vol: 87, Pages: A197-A198, ISSN: 1368-4973
Pickles M, Ramesh BM, Adhikary R, et al., 2011, QUANTIFYING SOCIAL DESIRABILITY BIASES IN REPORTED CONDOM USE AMONG FEMALE SEX WORKERS IN SOUTHERN INDIA, SEXUALLY TRANSMITTED INFECTIONS, Vol: 87, Pages: A162-A162, ISSN: 1368-4973
Mishra S, Boily MC, Steen R, et al., 2011, IMPACT OF TARGETED INTERVENTIONS IN HIV EPIDEMICS AS PREDICTED BY MATHEMATICAL MODELS: A SYSTEMATIC REVIEW, SEXUALLY TRANSMITTED INFECTIONS, Vol: 87, Pages: A35-A35, ISSN: 1368-4973
Boily MC, 2011, USE OF TRANSMISSION DYNAMICS MODELS TO DESIGN AND EVALUATE THE IMPACT OF LARGE SCALE HIV/STI PREVENTION INTERVENTION: HOW, WHY AND WHEN?, SEXUALLY TRANSMITTED INFECTIONS, Vol: 87, Pages: A4-A4, ISSN: 1368-4973
Pickles M, Boily MC, Vickerman P, et al., 2011, TIME EVOLUTION OF THE FRACTION OF NEW HIV INFECTIONS DUE TO PRIMARY INFECTION AMONG HIGH RISK GROUPS IN SOUTHERN INDIA, SEXUALLY TRANSMITTED INFECTIONS, Vol: 87, Pages: A50-A51, ISSN: 1368-4973
Boily M-C, 2011, THE USE OF TRANSMISSION DYNAMICS MODELS TO DESIGN AND EVALUATE THE IMPACT OF LARGE SCALE HIV PREVENTION PROGRAMMES, 3rd North American Congress of Epidemiology, Publisher: OXFORD UNIV PRESS INC, Pages: S80-S80, ISSN: 0002-9262
Baggaley RF, Powers KA, Boily M-C, 2011, What do mathematical models tell us about the emergence and spread of drug-resistant HIV?, CURRENT OPINION IN HIV AND AIDS, Vol: 6, Pages: 131-140, ISSN: 1746-630X
Mishra S, Boily M-C, Ng V, et al., 2011, The Laboratory Impact of Changing Syphilis Screening From the Rapid-Plasma Reagin to a Treponemal Enzyme Immunoassay: A Case-study From the Greater Toronto Area, SEXUALLY TRANSMITTED DISEASES, Vol: 38, Pages: 190-196, ISSN: 0148-5717
Brisson M, Van de Velde N, Boily M-C, 2011, Different population-level vaccination effectiveness for HPV types 16, 18, 6 and 11, SEXUALLY TRANSMITTED INFECTIONS, Vol: 87, Pages: 41-43, ISSN: 1368-4973
Mishra S, Fisman DN, Boily M-C, 2011, The ABC of terms used in mathematical models of infectious diseases, JOURNAL OF EPIDEMIOLOGY AND COMMUNITY HEALTH, Vol: 65, Pages: 87-94, ISSN: 0143-005X
Phillips AE, Gomez GB, Boily M-C, et al., 2010, A systematic review and meta-analysis of quantitative interviewing tools to investigate self-reported HIV and STI associated behaviours in low- and middle-income countries, INTERNATIONAL JOURNAL OF EPIDEMIOLOGY, Vol: 39, Pages: 1541-1555, ISSN: 0300-5771
Deering KN, Tyndall MW, Shoveller J, et al., 2010, Factors Associated With Numbers of Client Partners of Female Sex Workers Across Five Districts in South India, SEXUALLY TRANSMITTED DISEASES, Vol: 37, Pages: 687-695, ISSN: 0148-5717
Vickerman P, Foss AM, Pickles M, et al., 2010, To what extent is the HIV epidemic in southern India driven by commercial sex? A modelling analysis, AIDS, Vol: 24, Pages: 2554-2563, ISSN: 0269-9370
Baggaley RF, White RG, Boily M-C, 2010, Infectiousness of HIV-infected homosexual men in the era of highly active antiretroviral therapy, AIDS, Vol: 24, Pages: 2418-2420, ISSN: 0269-9370
Van de Velde N, Brisson M, Boily M-C, 2010, Understanding differences in predictions of HPV vaccine effectiveness: A comparative model-based analysis, VACCINE, Vol: 28, Pages: 5473-5484, ISSN: 0264-410X
Phillips AE, Gomez GB, Boily MC, et al., 2010, A systematic review and meta-analysis of quantitative interviewing tools to investigate self-reported HIV and STI associated behaviours in low- and middle-income countries., Int J Epidemiology. (in press).
Phillips AE, Lowndes CM, Boily MC, et al., 2010, Men who have sex with men and women inBangalore, South India, and potential impact on the HIV epidemic, Sex Transm Infect, Vol: 86, Pages: 187-192
Mishra S, Naik B, Venugopal B, et al., 2010, Syphilis screening among female sex workers in Bangalore, India: comparison of point-of-care testing and traditional serological approaches, SEXUALLY TRANSMITTED INFECTIONS, Vol: 86, Pages: 193-198, ISSN: 1368-4973
Baggaley RF, White RG, Boily M-C, 2010, HIV transmission risk through anal intercourse: systematic review, meta-analysis and implications for HIV prevention, International Journal of Epidemiology, Vol: 39, Pages: 1048-1063, ISSN: 1464-3685
Background The human immunodeficiency virus (HIV) infectiousness of anal intercourse (AI) has not been systematically reviewed, despite its role driving HIV epidemics among men who have sex with men (MSM) and its potential contribution to heterosexual spread. We assessed the per-act and per-partner HIV transmission risk from AI exposure for heterosexuals and MSM and its implications for HIV prevention.Methods Systematic review and meta-analysis of the literature on HIV-1 infectiousness through AI was conducted. PubMed was searched to September 2008. A binomial model explored the individual risk of HIV infection with and without highly active antiretroviral therapy (HAART).Results A total of 62 643 titles were searched; four publications reporting per-act and 12 reporting per-partner transmission estimates were included. Overall, random effects model summary estimates were 1.4% [95% confidence interval (CI) 0.2–2.5)] and 40.4% (95% CI 6.0–74.9) for per-act and per-partner unprotected receptive AI (URAI), respectively. There was no significant difference between per-act risks of URAI for heterosexuals and MSM. Per-partner unprotected insertive AI (UIAI) and combined URAI–UIAI risk were 21.7% (95% CI 0.2–43.3) and 39.9% (95% CI 22.5–57.4), respectively, with no available per-act estimates. Per-partner combined URAI–UIAI summary estimates, which adjusted for additional exposures other than AI with a ‘main’ partner [7.9% (95% CI 1.2–14.5)], were lower than crude (unadjusted) estimates [48.1% (95% CI 35.3–60.8)]. Our modelling demonstrated that it would require unreasonably low numbers of AI HIV exposures per partnership to reconcile the summary per-act and per-partner estimates, suggesting considerable variability in AI infectiousness between and within partnerships over time. AI may substantially increase HIV transmission risk even if the infected partner is receiving HAART; however, predictions are highly sens
Boily MC, 2010, Polygyny, concurrency, its impact and lack of impact on HIV, HIV Therapy, Vol: 4, Pages: 139-144, ISSN: 1758-4310
Evaluation of: Reniers G, Watkins S: Polygyny and the spread of HIV in sub-Saharan Africa: a case of benign concurrency. AIDS 24, 299-307 (2010). This ecological study aims to understand the role of concurrency on HIV in sub-Saharan Africa. The results showed a negative association between the prevalence of HIV and polygyny, independently of selected risk factors (e.g., age at sexual debut and extramarital sex). This reflects the potential protective role of this specific form of concurrency, which contrasts with the common understanding that concurrency favors the spread of HIV. More research is needed to understand how different concurrency patterns influence the global network structure, how they are associated with risk practices within partnerships and the motivation underlying concurrency. This is relevant for the design of intervention focusing on concurrency, to maximise impact and minimize the risk of negative compensatory risk behavior. These results illustrate a growing misinterpretation of early model results due to the underappreciation of the diversity of network structures and HIV epidemic sizes that can be produced when concurrency levels are high. © 2010 Future Medicine Ltd.
Pickles M, Foss AM, Vickerman P, et al., 2010, Interim modelling analysis to validate reported increases in condom use and assess HIV infections averted among female sex workers and clients in southern India following a targeted HIV prevention programme, SEXUALLY TRANSMITTED INFECTIONS, Vol: 86, Pages: I33-I43, ISSN: 1368-4973
Baggaley RF, Petersen ML, Soares MA, et al., 2010, Human immunodeficiency virus: Resistance to antiretroviral drugs in developing countries, Antimicrobial Resistance in Developing Countries, Pages: 75-94, ISBN: 9780387893693
© 2010 Springer Science Business Media, LLC. All rights reserved. This chapter reviews issues central to understanding the emergence and transmission of drug-resistant human immunodeficiency virus (HIV) and its impact on developing countries. We first give an overview of HIV, HIV treatment using antiretroviral drugs, and access to treatment in developing countries. Then we review current understanding of the impact of adherence and treatment interruption on the emergence of resistance among treated individuals (secondary resistance) and factors contributing to secondary resistance in resource-poor settings. Transmitted (or primary) resistance, which can threaten the effectiveness of antiretroviral regimens among treatment-naïve individuals, is also discussed. Furthermore, we address how antiretroviral delivery systems in developing countries may impact resistance. Mathematical models of HIV transmission offer important insights into the course of HIV epidemics and how expanded access and policies for antiretroviral delivery in developing countries may impact resistance. We summarize the major findings from published modeling studies and discuss their predictions and limitations. We then review available empirical data on antiretroviral resistance in developing countries. Finally, we discuss the implications of these findings for policy and the monitoring of epidemic trends.
Dimitrov DT, Masse B, Boily M-C, 2010, Who will Benefit from a Wide-Scale Introduction of Vaginal Microbicides in Developing Countries?, Stat Commun Infect Dis, Vol: 2, ISSN: 1948-4690
Vaginal microbicides (VMB) are currently among the few biomedical interventions designed to help women reduce their risk of acquiring HIV infection. However, the microbicide containing antiretroviral (ARV-VMB) may lead to the development of antiretroviral resistance and could paradoxically become more beneficial to men at the population level. We developed a mathematical model to study the impact of a wide-scale population usage of VMB in a heterosexual population. Gender ratios of prevented infections and prevalence reduction are evaluated in 63 different intervention schedules including continuous and interrupted ARV-VMB use by HIV-positive women. The influence of different factors on population-level benefits is also studied through Monte Carlo simulations using parameters sampled from primary ranges representative of developing countries. Our analysis indicates that women are more likely than men to benefit from ARV-VMB use since 78-80% of the total 63,000 simulations investigated (under different parameter sets) showed a female advantage whether benefit is measured as cumulative number of infections prevented, the percentage of cumulative infections prevented, or the expected reduction in prevalence. Stratified analysis by scenarios indicates that the likelihood of a male advantage with respect to the fractions of prevented infections varies from 6% to 49% among the scenarios. It is substantial only if the risk of systemic absorption and development of resistance to ARV-VMB is high and the HIV-positive women use VMB indefinitely without interruption. Therefore, the use of ARV-VMB, with successful control measures restricting usage by HIV-positive women, is still very much a female prevention tool.
Boily MC, Buvé A, Baggaley RF, 2010, HIV transmission in serodiscordant heterosexual couples., BMJ, Vol: 340
Boily M-C, Baggaley RF, Masse B, 2009, The role of heterosexual anal intercourse for HIV transmission in developing countries: are we ready to draw conclusions?, SEXUALLY TRANSMITTED INFECTIONS, Vol: 85, Pages: 408-410, ISSN: 1368-4973
Mâsse BR, Boily M-C, Dimitrov1 D, et al., 2009, Efficacy dilution in randomized placebo-controlled vaginal microbicide trials, Emerging themes in Epidemiology, Vol: 6
BackgroundTo date different vaginal gel microbicides have been evaluated in phase 2b/3 trials, but none have demonstrated effectiveness for preventing HIV infection. Failure to demonstrate effectiveness however does not necessarily indicate that a product is truly inefficacious, as several sources of efficacy dilution may compromise our ability to identify products that may have been truly efficacious.MethodsFor four individual sources of dilution, we describe the dilution mechanisms and quantify the expected effectiveness. An overall expected effectiveness that combines all sources of dilution in a trial is derived as well.ResultsUnder conditions that have been observed in recent microbicide trials, the overall expected effectiveness assuming an active gel with true efficacy of 50% and 75% are in the range of [16%; 33%] and [28%; 50%], respectively, when considering the four major sources of dilution. In contrast the diluting effect due to adherence alone (assuming an adherence of 80%) leads to higher expected effectiveness, 40% and 60% assuming an active gel with true efficacy of 50% and 75%, respectively. Individual sources of dilution may demonstrate a small effect when evaluated independently, but the overall dilution effect in a trial with several sources of dilution can be quite substantial.ConclusionCurrently planned phase 2b/3 microbicide trials of new candidate vaginal microbicides are not immune from these shortcomings. A good understanding of dilution effects is necessary to properly interpret microbicide trial results and to identify products worthy of further development and evaluation. Greater attention should be devoted to reducing and assessing the impact of efficacy dilution and to carefully selecting the effect size in the design of future trials.
Baggaley RF, Petersen ML, Soares MA, et al., 2009, Human Immunodeficiency Virus: Resistance to antiretroviral drugs in developing countries, Antimicrobial Resistance in Developing Countries, Editors: Sosa, Byarugaba, Amábile-Cuevas, Sosa, Byarugaba, Amábile-Cuevas, Publisher: Springer, Pages: 73-94, ISBN: 9780387893693
Scattered literature is available in various forms in journals that are often not easily accessible to the affected developing countries.The objective of the ...
Masse BR, Boily M-C, Desai K, 2009, Using Mathematical Modeling to Bridge Phase 3 Microbicide Trials With Public Health Decision Making, JAIDS-JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES, Vol: 50, Pages: 434-435, ISSN: 1525-4135
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.