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Cremin I, McKinnon L, Kimani J, Cherutich P, Gakii G, Muriuki F, Kripke K, Hecht R, Kiragu M, Smith J, Hinsley W, Gelmon L, Hallett TB. PrEP for key populations in combination HIV prevention in Nairobi: a mathematical modelling study. Lancet HIV 2017; 4:e214-e222. [PMID: 28233660 DOI: 10.1016/s2352-3018(17)30021-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 11/30/2016] [Accepted: 12/01/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND The HIV epidemic in the population of Nairobi as a whole is in decline, but a concentrated sub-epidemic persists in key populations. We aimed to identify an optimal portfolio of interventions to reduce HIV incidence for a given budget and to identify the circumstances in which pre-exposure prophylaxis (PrEP) could be used in Nairobi, Kenya. METHODS A mathematical model was developed to represent HIV transmission in specific key populations (female sex workers, male sex workers, and men who have sex with men [MSM]) and among the wider population of Nairobi. The scale-up of existing interventions (condom promotion, antiretroviral therapy, and male circumcision) for key populations and the wider population as have occurred in Nairobi is represented. The model includes a detailed representation of a PrEP intervention and is calibrated to prevalence and incidence estimates specific to key populations and the wider population. FINDINGS In the context of a declining epidemic overall but with a large sub-epidemic in MSM and male sex workers, an optimal prevention portfolio for Nairobi should focus on condom promotion for male sex workers and MSM in particular, followed by improved antiretroviral therapy retention, earlier antiretroviral therapy, and male circumcision as the budget allows. PrEP for male sex workers could enter an optimal portfolio at similar levels of spending to when earlier antiretroviral therapy is included; however, PrEP for MSM and female sex workers would be included only at much higher budgets. If PrEP for male sex workers cost as much as US$500, average annual spending on the interventions modelled would need to be less than $3·27 million for PrEP for male sex workers to be excluded from an optimal portfolio. Estimated costs per infection averted when providing PrEP to all female sex workers regardless of their risk of infection, and to high-risk female sex workers only, are $65 160 (95% credible interval [CrI] $43 520-$90 250) and $10 920 (95% CrI $4700-$51 560), respectively. INTERPRETATION PrEP could be a useful contribution to combination prevention, especially for under-served key populations in Nairobi. An ongoing demonstration project will provide important information regarding practical aspects of implementing PrEP for key populations in this setting. FUNDING The Bill & Melinda Gates Foundation.
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Affiliation(s)
- Ide Cremin
- Department of Infectious Disease Epidemiology, Imperial College London, London, UK.
| | - Lyle McKinnon
- Department of Medical Microbiology, University of Manitoba, Winnipeg, Canada; Department of Medical Microbiology, University of Nairobi, Nairobi, Kenya; Centre for the AIDS Programme of Research in South Africa (CAPRISA), Durban, South Africa
| | - Joshua Kimani
- Department of Medical Microbiology, University of Manitoba, Winnipeg, Canada; Department of Medical Microbiology, University of Nairobi, Nairobi, Kenya; Sex Worker Outreach Program, Nairobi, Kenya
| | | | - Gloria Gakii
- Department of Medical Microbiology, University of Manitoba, Winnipeg, Canada; Department of Medical Microbiology, University of Nairobi, Nairobi, Kenya; Sex Worker Outreach Program, Nairobi, Kenya
| | - Festus Muriuki
- Department of Medical Microbiology, University of Nairobi, Nairobi, Kenya; Sex Worker Outreach Program, Nairobi, Kenya
| | | | - Robert Hecht
- Pharos Global Health Advisors, Washington, DC, USA
| | | | - Jennifer Smith
- Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Wes Hinsley
- Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Lawrence Gelmon
- Department of Medical Microbiology, University of Manitoba, Winnipeg, Canada; Department of Medical Microbiology, University of Nairobi, Nairobi, Kenya; Sex Worker Outreach Program, Nairobi, Kenya
| | - Timothy B Hallett
- Department of Infectious Disease Epidemiology, Imperial College London, London, UK
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Jewell BL, Cremin I, Pickles M, Celum C, Baeten JM, Delany-Moretlwe S, Hallett TB. Estimating the cost-effectiveness of pre-exposure prophylaxis to reduce HIV-1 and HSV-2 incidence in HIV-serodiscordant couples in South Africa. PLoS One 2015; 10:e0115511. [PMID: 25616135 PMCID: PMC4304839 DOI: 10.1371/journal.pone.0115511] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 11/25/2014] [Indexed: 01/12/2023] Open
Abstract
OBJECTIVE To estimate the cost-effectiveness of daily oral tenofovir-based PrEP, with a protective effect against HSV-2 as well as HIV-1, among HIV-1 serodiscordant couples in South Africa. METHODS We incorporated HSV-2 acquisition, transmission, and interaction with HIV-1 into a microsimulation model of heterosexual HIV-1 serodiscordant couples in South Africa, with use of PrEP for the HIV-1 uninfected partner prior to ART initiation for the HIV-1 1infected partner, and for one year thereafter. RESULTS We estimate the cost per disability-adjusted life-year (DALY) averted for two scenarios, one in which PrEP has no effect on reducing HSV-2 acquisition, and one in which there is a 33% reduction. After a twenty-year intervention, the cost per DALY averted is estimated to be $10,383 and $9,757, respectively--a 6% reduction, given the additional benefit of reduced HSV-2 acquisition. If all couples are discordant for both HIV-1 and HSV-2, the cost per DALY averted falls to $1,445, which shows that the impact is limited by HSV-2 concordance in couples. CONCLUSION After a 20-year PrEP intervention, the cost per DALY averted with a reduction in HSV-2 is estimated to be modestly lower than without any effect, providing an increase of health benefits in addition to HIV-1 prevention at no extra cost. The small degree of the effect is in part due to a high prevalence of HSV-2 infection in HIV-1 serodiscordant couples in South Africa.
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Affiliation(s)
- Britta L. Jewell
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Ide Cremin
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Michael Pickles
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Connie Celum
- Departments of Global Health, Medicine and Epidemiology, University of Washington, Seattle, Washington, United States of America
| | - Jared M. Baeten
- Departments of Global Health, Medicine and Epidemiology, University of Washington, Seattle, Washington, United States of America
| | - Sinead Delany-Moretlwe
- Wits Reproductive Health and HIV Institute, University of the Witwatersrand, Johannesburg, South Africa
| | - Timothy B. Hallett
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
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Anderson SJ, Cherutich P, Kilonzo N, Cremin I, Fecht D, Kimanga D, Harper M, Masha RL, Ngongo PB, Maina W, Dybul M, Hallett TB. Maximising the effect of combination HIV prevention through prioritisation of the people and places in greatest need: a modelling study. Lancet 2014; 384:249-56. [PMID: 25042235 DOI: 10.1016/s0140-6736(14)61053-9] [Citation(s) in RCA: 190] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Epidemiological data show substantial variation in the risk of HIV infection between communities within African countries. We hypothesised that focusing appropriate interventions on geographies and key populations at high risk of HIV infection could improve the effect of investments in the HIV response. METHODS With use of Kenya as a case study, we developed a mathematical model that described the spatiotemporal evolution of the HIV epidemic and that incorporated the demographic, behavioural, and programmatic differences across subnational units. Modelled interventions (male circumcision, behaviour change communication, early antiretoviral therapy, and pre-exposure prophylaxis) could be provided to different population groups according to their risk behaviours or their location. For a given national budget, we compared the effect of a uniform intervention strategy, in which the same complement of interventions is provided across the country, with a focused strategy that tailors the set of interventions and amount of resources allocated to the local epidemiological conditions. FINDINGS A uniformly distributed combination of HIV prevention interventions could reduce the total number of new HIV infections by 40% during a 15-year period. With no additional spending, this effect could be increased by 14% during the 15 years-almost 100,000 extra infections, and result in 33% fewer new HIV infections occurring every year by the end of the period if the focused approach is used to tailor resource allocation to reflect patterns in local epidemiology. The cumulative difference in new infections during the 15-year projection period depends on total budget and costs of interventions, and could be as great as 150,000 (a cumulative difference as great as 22%) under different assumptions about the unit costs of intervention. INTERPRETATION The focused approach achieves greater effect than the uniform approach despite exactly the same investment. Through prioritisation of the people and locations at greatest risk of infection, and adaption of the interventions to reflect the local epidemiological context, the focused approach could substantially increase the efficiency and effectiveness of investments in HIV prevention. FUNDING The Bill & Melinda Gates Foundation and UNAIDS.
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Affiliation(s)
- Sarah-Jane Anderson
- Department of Infectious Disease Epidemiology, Imperial College London, London, UK.
| | - Peter Cherutich
- National AIDS & STI Control Programme (NASCOP), Nairobi, Kenya
| | | | - Ide Cremin
- Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Daniela Fecht
- Small Area Health Statistics Unit (SAHSU), MRC-PHE Centre for Environment and Health, Imperial College London, London, UK
| | - Davies Kimanga
- National AIDS & STI Control Programme (NASCOP), Nairobi, Kenya
| | | | | | | | - William Maina
- National AIDS & STI Control Programme (NASCOP), Nairobi, Kenya
| | - Mark Dybul
- The Global Fund to Fight AIDS, Tuberculosis and Malaria, Geneva, Switzerland
| | - Timothy B Hallett
- Department of Infectious Disease Epidemiology, Imperial College London, London, UK
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Jones A, Cremin I, Abdullah F, Idoko J, Cherutich P, Kilonzo N, Rees H, Hallett T, O'Reilly K, Koechlin F, Schwartlander B, de Zalduondo B, Kim S, Jay J, Huh J, Piot P, Dybul M. Transformation of HIV from pandemic to low-endemic levels: a public health approach to combination prevention. Lancet 2014; 384:272-9. [PMID: 24740087 DOI: 10.1016/s0140-6736(13)62230-8] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Large declines in HIV incidence have been reported since 2001, and scientific advances in HIV prevention provide strong hope to reduce incidence further. Now is the time to replace the quest for so-called silver bullets with a public health approach to combination prevention that understands that risk is not evenly distributed and that effective interventions can vary by risk profile. Different countries have different microepidemics, with very different levels of transmission and risk groups, changing over time. Therefore, focus should be on high-transmission geographies, people at highest risk for HIV, and the package of interventions that are most likely to have the largest effect in each different microepidemic. Building on the backbone of behaviour change, condom use, and medical male circumcision, as well as expanded use of antiretroviral drugs for infected people and pre-exposure prophylaxis for uninfected people at high risk of infection, it is now possible to consider the prospect of what would be one of the most remarkable achievements in the history of public health: reduction of HIV transmission from a pandemic to low-level endemicity.
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Affiliation(s)
- Alexandra Jones
- O'Neill Institute for National and Global Health Law, Georgetown University Law Center, Washington, DC, USA
| | - Ide Cremin
- School of Public Health, Imperial College London, London, UK
| | - Fareed Abdullah
- South Africa National AIDS Council (SANAC), Pretoria, South Africa
| | - John Idoko
- National Agency for the Control of AIDS, Abuja, Nigeria
| | - Peter Cherutich
- National AIDS/STD Control Programme (NASCOP), Nairobi, Kenya
| | - Nduku Kilonzo
- Liverpool Voluntary Counselling and Testing, Care and Treatment, Nairobi, Kenya
| | - Helen Rees
- Wits Reproductive Health and HIV Institute, University of Witwatersrand, Witwatersrand, South Africa
| | - Timothy Hallett
- School of Public Health, Imperial College London, London, UK
| | - Kevin O'Reilly
- Department of HIV/AIDS, World Health Organization, Geneva, Switzerland
| | - Florence Koechlin
- Department of HIV/AIDS, World Health Organization, Geneva, Switzerland
| | | | - Barbara de Zalduondo
- Office of the Deputy Executive Director for Programme, UNAIDS, Geneva, Switzerland
| | - Susan Kim
- O'Neill Institute for National and Global Health Law, Georgetown University Law Center, Washington, DC, USA
| | - Jonathan Jay
- O'Neill Institute for National and Global Health Law, Georgetown University Law Center, Washington, DC, USA
| | - Jacqueline Huh
- O'Neill Institute for National and Global Health Law, Georgetown University Law Center, Washington, DC, USA
| | - Peter Piot
- Director's Office, London School of Hygiene and Tropical Medicine, London, UK
| | - Mark Dybul
- O'Neill Institute for National and Global Health Law, Georgetown University Law Center, Washington, DC, USA; The Global Fund to Fight AIDS, Tuberculosis and Malaria, Geneva, Switzerland.
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Abstract
Objectives To compare nationally representative trends in self-reported uptake of HIV testing and receipt of results in selected countries prior to treatment scale-up. Methods Demographic and Health Survey (DHS) data from 13 countries in sub-Saharan Africa were used to describe the pattern of uptake of testing for HIV among sexually active participants. Univariate and multivariate logistic regression were used to analyse the associations between socio-demographic and behavioural characteristics and the uptake of testing. Results Knowledge of serostatus ranged from 2.2% among women in Guinea (2005) to 27.4% among women in Rwanda (2005). Despite varied levels of testing, univariate analysis showed the profile of testers to be remarkably similar across countries, with respect to socio-demographic characteristics such as area of residence and socio-economic status. HIV-positive participants were more likely to have tested and received their results than HIV-negative participants, with the exception of women in Senegal and men in Guinea. Adjusted analyses indicate that a secondary or higher level of education was a key determinant of testing, and awareness that treatment exists was independently positively associated with testing, once other characteristics were taken into account. Conclusion This work provides a baseline for monitoring trends in testing and exploring changes in the profile of those who get tested after the introduction and scale-up of treatment.
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Affiliation(s)
- Ide Cremin
- Department of Infectious Disease Epidemiology, Imperial College London, London, UK.
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Chemaitelly H, Cremin I, Shelton J, Hallett TB, Abu-Raddad LJ. Distinct HIV discordancy patterns by epidemic size in stable sexual partnerships in sub-Saharan Africa. Sex Transm Infect 2012; 88:51-7. [PMID: 22250180 PMCID: PMC3261749 DOI: 10.1136/sextrans-2011-050114] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Objective To describe patterns of HIV infection among stable sexual partnerships across sub-Saharan Africa (SSA). Methods The authors defined measures of HIV discordancy and conducted a comprehensive quantitative assessment of discordancy among stable partnerships in 20 countries in SSA through an analysis of the Demographic and Health Survey data. Results HIV prevalence explained at least 50% of the variation in HIV discordancy, with two distinct patterns of discordancy emerging based on HIV prevalence being roughly smaller or larger than 10%. In low-prevalence countries, approximately 75% of partnerships affected by HIV are discordant, while only about half of these are discordant in high-prevalence countries. Out of each 10 HIV infected persons, two to five are engaged in discordant partnerships in low-prevalence countries compared with one to three in high-prevalence countries. Among every 100 partnerships in the population, one to nine are affected by HIV and zero to six are discordant in low-prevalence countries compared with 16–45 and 9–17, respectively, in high-prevalence countries. Finally, zero to four of every 100 sexually active adults are engaged in a discordant partnership in low-prevalence countries compared with six to eight in high-prevalence countries. Conclusions In high-prevalence countries, a large fraction of stable partnerships were affected by HIV and half were discordant, whereas in low-prevalence countries, fewer stable partnerships were affected by HIV but a higher proportion of them were discordant. The findings provide a global view of HIV infection among stable partnerships in SSA but imply complex considerations for rolling out prevention interventions targeting discordant partnerships.
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Affiliation(s)
- Hiam Chemaitelly
- Infectious Disease Epidemiology Group, Weill Cornell Medical College--Qatar, Cornell University, Qatar Foundation--Education City, Doha, Qatar
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Smit M, Smit C, Cremin I, Hallett T, de Wolf F, Garnett G. P3-S3.09 New drugs targeting toxicities have highest hope of impacting patient prognosis. Br J Vener Dis 2011. [DOI: 10.1136/sextrans-2011-050108.458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Cremin I, Hallett T, Dybul M, Piot P, Garnett G. O1-S06.03 Pre-exposure prophylaxis for HIV prevention. Br J Vener Dis 2011. [DOI: 10.1136/sextrans-2011-050109.33] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Cremin I, Mushati P, Hallett T, Mupambireyi Z, Nyamukapa C, Garnett GP, Gregson S. Measuring trends in age at first sex and age at marriage in Manicaland, Zimbabwe. Sex Transm Infect 2009; 85 Suppl 1:i34-40. [PMID: 19307339 PMCID: PMC2654143 DOI: 10.1136/sti.2008.033431] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE To identify reporting biases and to determine the influence of inconsistent reporting on observed trends in the timing of age at first sex and age at marriage. METHODS Longitudinal data from three rounds of a population-based cohort in eastern Zimbabwe were analysed. Reports of age at first sex and age at marriage from 6837 individuals attending multiple rounds were classified according to consistency. Survival analysis was used to identify trends in the timing of first sex and marriage. RESULTS In this population, women initiate sex and enter marriage at younger ages than men but spend much less time between first sex and marriage. Among those surveyed between 1998 and 2005, median ages at first sex and first marriage were 18.5 years and 21.4 years for men and 18.2 years and 18.5 years, respectively, for women aged 15-54 years. High levels of reports of both age at first sex and age at marriage among those attending multiple surveys were found to be unreliable. Excluding reports identified as unreliable from these analyses did not alter the observed trends in either age at first sex or age at marriage. Tracing birth cohorts as they aged revealed reporting biases, particularly among the youngest cohorts. Comparisons by birth cohorts, which span a period of >40 years, indicate that median age at first sex has remained constant over time for women but has declined gradually for men. CONCLUSIONS Although many reports of age at first sex and age at marriage were found to be unreliable, inclusion of such reports did not result in artificial generation or suppression of trends.
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Affiliation(s)
- I Cremin
- Department of Infectious Disease Epidemiology, Imperial College London, London, UK.
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Todd J, Cremin I, McGrath N, Bwanika JB, Wringe A, Marston M, Kasamba I, Mushati P, Lutalo T, Hosegood V, Zaba B. Reported number of sexual partners: comparison of data from four African longitudinal studies. Sex Transm Infect 2009; 85 Suppl 1:i72-80. [PMID: 19307344 PMCID: PMC2654146 DOI: 10.1136/sti.2008.033985] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2008] [Indexed: 11/20/2022] Open
Abstract
OBJECTIVE To compare reported numbers of sexual partners in Eastern and Southern Africa. METHODS Sexual partnership data from four longitudinal population-based surveys (1998-2007) in Zimbabwe, Uganda and South Africa were aggregated and overall proportions reporting more than one lifetime sexual partner calculated. A lexis-style table was used to illustrate the average lifetime sexual partners by site, sex, age group and birth cohort. The male-to-female ratio of mean number of partnerships in the last 12 months was calculated by site and survey. For each single year of age, the proportion sexually active in the past year, the mean number of partners in the past year and the proportion with more than one partner in the past year were calculated. RESULTS Over 90% of men and women between 25 and 45 years of age reported being sexually active during the past 12 months, with most reporting at least one sexual partner. Overall, men reported higher numbers of lifetime sexual partners and partners in the last year than women. The male-to-female ratio of mean partnerships in the last year ranged from 1.41 to 1.86. In southern African cohorts, individuals in later birth cohorts reported fewer sexual partners and a lower proportion reported multiple partnerships compared with earlier birth cohorts, whereas these behavioural changes were not observed in the Ugandan cohorts. Across the four sites, reports of sexual partnerships followed a similar pattern for each sex. CONCLUSIONS The longitudinal results show that reductions in the number of partnerships were more evident in southern Africa than in Uganda.
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Affiliation(s)
- J Todd
- Medical Research Council/Uganda Virus Research Institute, Uganda Research Unit on AIDS, Entebbe, Uganda.
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Wringe A, Cremin I, Todd J, McGrath N, Kasamba I, Herbst K, Mushore P, Zaba B, Slaymaker E. Comparative assessment of the quality of age-at-event reporting in three HIV cohort studies in sub-Saharan Africa. Sex Transm Infect 2009; 85 Suppl 1:i56-63. [PMID: 19307342 PMCID: PMC2654104 DOI: 10.1136/sti.2008.033423] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2008] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVES To assess inconsistencies in reported age at first sex (AFS) and age at first marriage (AFM) in three African cohorts, and consider their implications for interpreting trends in sexual and marital debut. METHODS Data were analysed from population-based cohort studies in Zimbabwe, Uganda and South Africa with 3, 10 and 4 behavioural survey rounds, respectively. Three rounds over a similar time frame were selected from each site for comparative purposes. The consistency of AFS and AFM reports was assessed for each site by comparing responses made by participants in multiple surveys. Respondents were defined as unreliable if less than half of all their age-at-event reports were the same. Kaplan-Meier functions were used to describe the cumulative proportion (1) having had sex and (2) married by age, stratified by sex, birth cohort and site, to compare the influence of reporting inconsistencies on these estimates. RESULTS Among participants attending all three comparable rounds, the percentage with unreliable AFS reports ranged from 30% among South African women to 56% among Zimbabwean men, with similar patterns observed for AFM. Inclusion of unreliable reports had little effect on estimates of median age-at-event in all sites. There was some evidence from the 1960-9 birth cohort that women in Uganda and both sexes in South Africa reported later AFS as they aged. CONCLUSION Although reporting quality is unlikely to affect comparisons of AFS and AFM between settings, care should be taken not to overinterpret small changes in reported age-at-event over time within each site.
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Affiliation(s)
- A Wringe
- Centre for Population Studies, London School of Hygiene and Tropical Medicine, London, UK.
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Marston M, Slaymaker E, Cremin I, Floyd S, McGrath N, Kasamba I, Lutalo T, Nyirenda M, Ndyanabo A, Mupambireyi Z, Zaba B. Trends in marriage and time spent single in sub-Saharan Africa: a comparative analysis of six population-based cohort studies and nine Demographic and Health Surveys. Sex Transm Infect 2009; 85 Suppl 1:i64-71. [PMID: 19307343 PMCID: PMC2654103 DOI: 10.1136/sti.2008.034249] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/20/2009] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVES To describe trends in age at first sex (AFS), age at first marriage (AFM) and time spent single between events and to compare age-specific trends in marital status in six cohort studies. METHODS Cohort data from Uganda, Tanzania, South Africa, Zimbabwe and Malawi and Demographic and Health Survey (DHS) data from Uganda, Tanzania and Zimbabwe were analysed. Life table methods were used to calculate median AFS, AFM and time spent single. In each study, two surveys were chosen to compare marital status by age and identify changes over time. RESULTS Median AFM was much higher in South Africa than in the other sites. Between the other populations there were considerable differences in median AFS and AFM (AFS 17-19 years for men and 16-19 years for women, AFM 21-24 years and 18-19 years, respectively, for the 1970-9 birth cohort). In all surveys, men reported a longer time spent single than women (median 4-7 years for men and 0-2 years for women). Median years spent single for women has increased, apart from in Manicaland. For men in Rakai it has decreased slightly over time but increased in Kisesa and Masaka. The DHS data showed similar trends to those in the cohort data. The age-specific proportion of married individuals has changed little over time. CONCLUSIONS Median AFS, AFM and time spent single vary considerably among these populations. These three measures are underlying determinants of sexual risk and HIV infection, and they may partially explain the variation in HIV prevalence levels between these populations.
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Affiliation(s)
- M Marston
- Centre for Population Studies, London School of Hygiene and Tropical Medicine, London, UK.
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Hallett TB, Dube S, Cremin I, Lopman B, Mahomva A, Ncube G, Mugurungi O, Gregson S, Garnett GP. The role of testing and counselling for HIV prevention and care in the era of scaling-up antiretroviral therapy. Epidemics 2009; 1:77-82. [PMID: 21352753 DOI: 10.1016/j.epidem.2009.02.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Revised: 11/16/2008] [Accepted: 02/27/2009] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE HIV Testing and Counselling (TC) programmes are being scaled-up as part of efforts to provide universal access to antiretroviral treatment (ART). METHODS AND FINDINGS Mathematical modelling of TC in Zimbabwe shows that if universal access is to be sustained, TC must include prevention counselling that enables behaviour change among infected and uninfected individuals. The predicted impact TC is modest, but improved programmes could generate substantial reductions in incidence, reducing need for ART in the long-term. CONCLUSIONS TC programmes that focus only on identifying those in need of treatment will not be sufficient to bring the epidemic under control.
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Affiliation(s)
- T B Hallett
- Department of Infectious Disease Epidemiology, Imperial College London, Norfolk Place, London, UK.
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Sherr L, Lopman B, Kakowa M, Dube S, Chawira G, Nyamukapa C, Oberzaucher N, Cremin I, Gregson S. Voluntary counselling and testing: uptake, impact on sexual behaviour, and HIV incidence in a rural Zimbabwean cohort. AIDS 2007; 21:851-60. [PMID: 17415040 DOI: 10.1097/qad.0b013e32805e8711] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
OBJECTIVES To examine the determinants of uptake of voluntary counselling and testing (VCT) services, to assess changes in sexual risk behaviour following VCT, and to compare HIV incidence amongst testers and non-testers. METHODS Prospective population-based cohort study of adult men and women in the Manicaland province of eastern Zimbabwe. Demographic, socioeconomic, sexual behaviour and VCT utilization data were collected at baseline (1998-2000) and follow-up (3 years later). HIV status was determined by HIV-1 antibody detection. In addition to services provided by the government and non-governmental organizations, a mobile VCT clinic was available at study sites. RESULTS Lifetime uptake of VCT increased from under 6% to 11% at follow-up. Age, increasing education and knowledge of HIV were associated with VCT uptake. Women who took a test were more likely to be HIV positive and to have greater HIV knowledge and fewer total lifetime partners. After controlling for demographic characteristics, sexual behaviour was not independently associated with VCT uptake. Women who tested positive reported increased consistent condom use in their regular partnerships. However, individuals who tested negative were more likely to adopt more risky behaviours in terms of numbers of partnerships in the last month, the last year and in concurrent partnerships. HIV incidence during follow-up did not differ between testers and non-testers. CONCLUSION Motivation for VCT uptake was driven by knowledge and education rather than sexual risk. Increased sexual risk following receipt of a negative result may be a serious unintended consequence of VCT. It should be minimized with appropriate pre- and post-test counselling.
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