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Niyukuri D, Nyasulu P, Delva W. Assessing the uncertainty around age-mixing patterns in HIV transmission inferred from phylogenetic trees. PLoS One 2021; 16:e0249013. [PMID: 33765091 PMCID: PMC7993798 DOI: 10.1371/journal.pone.0249013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Accepted: 03/10/2021] [Indexed: 11/18/2022] Open
Abstract
Understanding age-mixing patterns in Human Immunodeficiency Virus (HIV) transmission networks can enhance the design and implementation of HIV prevention strategies in sub-Saharan Africa. Due to ethical consideration, it is less likely possible to conduct a benchmark study to assess which sampling strategy, and sub-optimal sampling coverage which can yield best estimates for these patterns. We conducted a simulation study, using phylogenetic trees to infer estimates of age-mixing patterns in HIV transmission, through the computation of proportions of pairings between men and women, who were phylogenetically linked across different age groups (15-24 years, 25-39 years, and 40-49 years); and the means, and standard deviations of their age difference. We investigated also the uncertainty around these estimates as a function of the sampling coverage in four sampling strategies: when missing sequence data were missing completely at random (MCAR), and missing at random (MAR) with at most 30%-50%-70% of women in different age groups being in the sample. The results suggested that age-mixing patterns in HIV transmission can be unveiled from proportions of phylogenetic pairings between men and women across age groups; and the mean, and standard deviation of their age difference. A 55% sampling coverage was sufficient to provide the best values of estimates of age-mixing patterns in HIV transmission with MCAR scenario. But we should be cautious in interpreting proportions of men phylogenetically linked to women because they may be overestimated or underestimated, even at higher sampling coverage. The findings showed that, MCAR was the best sampling strategy. This means, it is advisable not to use sequence data collected in settings where we can find a systematic imbalance of age and gender to investigate age-mixing in HIV transmission. If not possible, ensure to take into consideration the imbalance in interpreting the results.
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Affiliation(s)
- David Niyukuri
- Division of Epidemiology & Biostatistics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
- The South African Department of Science and Technology–National Research Foundation (DST-NRF) Centre of Excellence in Epidemiological Modelling and Analysis (SACEMA), Stellenbosch University, Cape Town, South Africa
- * E-mail:
| | - Peter Nyasulu
- Division of Epidemiology & Biostatistics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
- Division of Epidemiology & Biostatistics, School of Public Health, Faculty of Health, University of the Witwatersrand, Johannesburg, South Africa
| | - Wim Delva
- Division of Epidemiology & Biostatistics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
- The South African Department of Science and Technology–National Research Foundation (DST-NRF) Centre of Excellence in Epidemiological Modelling and Analysis (SACEMA), Stellenbosch University, Cape Town, South Africa
- Center for Statistics, I-BioStat, Hasselt University, Diepenbeek, Belgium
- International Centre for Reproductive Health, Ghent University, Ghent, Belgium
- Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
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Beauclair R, Hens N, Delva W. The role of age-mixing patterns in HIV transmission dynamics: Novel hypotheses from a field study in Cape Town, South Africa. Epidemics 2018; 25:61-71. [PMID: 29866422 DOI: 10.1016/j.epidem.2018.05.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 02/15/2018] [Accepted: 05/17/2018] [Indexed: 10/16/2022] Open
Abstract
BACKGROUND Age-disparate relationships are thought to put young women at increased risk of HIV, though current evidence is inconclusive. Studying population-level age-mixing patterns as well as individual-level measures of age difference variation may provide insight into the persistence and magnitude of the epidemic in South Africa. METHODS We used data from a survey in Cape Town (n = 506) to describe age-mixing dynamics in the four population strata of HIV negative and HIV positive male and female participants. Mixed-effects models were used to calculate the average increase in partner age for each year increase in age of participant, the average partner age for 15 year olds, and the between-subject and the within-subject standard deviation of partner ages. We conducted 2000 bootstrap replications of the models. Using negative binomial models, we also explored whether HIV status was associated with participants having a larger range in partner ages. RESULTS HIV positive women had large variability in partner ages at the population level, and at the individual level had nearly three times the expected range of partner ages compared to HIV negative women. This pattern may increase the potential for HIV transmission across birth cohorts and may partially explain the persistence of the epidemic in South Africa. Young men, who have been previously absent from the age-disparity discourse, also choose older partners who may be putting them at increased risk of HIV infection due to the high HIV prevalence among older age categories of women.
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Affiliation(s)
- Roxanne Beauclair
- International Centre for Reproductive Health, Ghent University, Gent, Belgium; The South African Department of Science and Technology-National Research Foundation (DST-NRF) Centre of Excellence in Epidemiological Modelling and Analysis (SACEMA), Stellenbosch University, Stellenbosch, South Africa.
| | - Niel Hens
- Center for Statistics, I-BioStat, Hasselt University, Martelarenlaan 42, BE3500 Hasselt, Belgium; Centre for Health Economics Research and Modelling Infectious Diseases and Centre for the Evaluation of Vaccination, Vaccine & Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
| | - Wim Delva
- International Centre for Reproductive Health, Ghent University, Gent, Belgium; The South African Department of Science and Technology-National Research Foundation (DST-NRF) Centre of Excellence in Epidemiological Modelling and Analysis (SACEMA), Stellenbosch University, Stellenbosch, South Africa; Center for Statistics, I-BioStat, Hasselt University, Martelarenlaan 42, BE3500 Hasselt, Belgium; Rega Institute for Medical Research, KU Leuven, Herestraat 49, 3000 Leuven, Belgium; Department of Global Health Faculty of Medicine and Health Sciences, Stellenbosch University, Stellenbosch, South Africa
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Kemp CG, de Kadt J, Pillay E, Gilvydis JM, Naidoo E, Grignon J, Weaver MR. Pre/post evaluation of a pilot prevention with positives training program for healthcare providers in North West Province, Republic of South Africa. BMC Health Serv Res 2017; 17:316. [PMID: 28464926 PMCID: PMC5414361 DOI: 10.1186/s12913-017-2263-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 04/24/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Prevention interventions for people living with HIV/AIDS are an important component of HIV programs. We report the results of a pilot evaluation of a four-hour, clinic-based training for healthcare providers in South Africa on HIV prevention assessments and messages. This pre/post pilot evaluation examined whether the training was associated with providers delivering more prevention messages. METHODS Seventy providers were trained at four public primary care clinics with a high volume of HIV patients. Pre- and post-training patient exit surveys were conducted using Audio-Computer Assisted Structured Interviews. Seven provider appropriate messaging outcomes and one summary provider outcome were compared pre- and post-training using Poisson regression. RESULTS Four hundred fifty-nine patients pre-training and 405 post-training with known HIV status were interviewed, including 175 and 176 HIV positive patients respectively. Among HIV positive patients, delivery of all appropriate messages by providers declined post-training. The summary outcome decreased from 56 to 50%; adjusted rate ratio 0.92 (95% CI = 0.87-0.97). Sensitivity analyses adjusting for training coverage and time since training detected fewer declines. Among HIV negative patients the summary score was stable at 32% pre- and post-training; adjusted rate ratio 1.05 (95% CI = 0.98-1.12). CONCLUSIONS Surprisingly, this training was associated with a decrease in prevention messages delivered to HIV positive patients by providers. Limited training coverage and delays between training and post-training survey may partially account for this apparent decrease. A more targeted approach to prevention messages may be more effective.
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Affiliation(s)
- Christopher G. Kemp
- Department of Global Health, University of Washington, Ninth and Jefferson Building, 13th Floor, Box 359932, 908 Jefferson Street, Seattle, WA 98104 USA
- International Training and Education Center for Health (I-TECH), University of Washington, 908 Jefferson Street, Seattle, WA 98104 USA
| | - Julia de Kadt
- I-TECH South Africa, 232 Bronkhorst St, Suite 203 Optiplan House, Nieuw Muckleneuk, Pretoria, South Africa
| | - Erushka Pillay
- I-TECH South Africa, 232 Bronkhorst St, Suite 203 Optiplan House, Nieuw Muckleneuk, Pretoria, South Africa
- Project Hope, 255 Carter Hall Lane, PO Box 250, Millwood, VA 22646 USA
| | - Jennifer M. Gilvydis
- Department of Global Health, University of Washington, Ninth and Jefferson Building, 13th Floor, Box 359932, 908 Jefferson Street, Seattle, WA 98104 USA
- International Training and Education Center for Health (I-TECH), University of Washington, 908 Jefferson Street, Seattle, WA 98104 USA
| | - Evasen Naidoo
- I-TECH South Africa, 232 Bronkhorst St, Suite 203 Optiplan House, Nieuw Muckleneuk, Pretoria, South Africa
| | - Jessica Grignon
- Department of Global Health, University of Washington, Ninth and Jefferson Building, 13th Floor, Box 359932, 908 Jefferson Street, Seattle, WA 98104 USA
- I-TECH South Africa, 232 Bronkhorst St, Suite 203 Optiplan House, Nieuw Muckleneuk, Pretoria, South Africa
| | - Marcia R. Weaver
- Department of Global Health, University of Washington, Ninth and Jefferson Building, 13th Floor, Box 359932, 908 Jefferson Street, Seattle, WA 98104 USA
- International Training and Education Center for Health (I-TECH), University of Washington, 908 Jefferson Street, Seattle, WA 98104 USA
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Bórquez A, Cori A, Pufall EL, Kasule J, Slaymaker E, Price A, Elmes J, Zaba B, Crampin AC, Kagaayi J, Lutalo T, Urassa M, Gregson S, Hallett TB. The Incidence Patterns Model to Estimate the Distribution of New HIV Infections in Sub-Saharan Africa: Development and Validation of a Mathematical Model. PLoS Med 2016; 13:e1002121. [PMID: 27622516 PMCID: PMC5021265 DOI: 10.1371/journal.pmed.1002121] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 08/03/2016] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Programmatic planning in HIV requires estimates of the distribution of new HIV infections according to identifiable characteristics of individuals. In sub-Saharan Africa, robust routine data sources and historical epidemiological observations are available to inform and validate such estimates. METHODS AND FINDINGS We developed a predictive model, the Incidence Patterns Model (IPM), representing populations according to factors that have been demonstrated to be strongly associated with HIV acquisition risk: gender, marital/sexual activity status, geographic location, "key populations" based on risk behaviours (sex work, injecting drug use, and male-to-male sex), HIV and ART status within married or cohabiting unions, and circumcision status. The IPM estimates the distribution of new infections acquired by group based on these factors within a Bayesian framework accounting for regional prior information on demographic and epidemiological characteristics from trials or observational studies. We validated and trained the model against direct observations of HIV incidence by group in seven rounds of cohort data from four studies ("sites") conducted in Manicaland, Zimbabwe; Rakai, Uganda; Karonga, Malawi; and Kisesa, Tanzania. The IPM performed well, with the projections' credible intervals for the proportion of new infections per group overlapping the data's confidence intervals for all groups in all rounds of data. In terms of geographical distribution, the projections' credible intervals overlapped the confidence intervals for four out of seven rounds, which were used as proxies for administrative divisions in a country. We assessed model performance after internal training (within one site) and external training (between sites) by comparing mean posterior log-likelihoods and used the best model to estimate the distribution of HIV incidence in six countries (Gabon, Kenya, Malawi, Rwanda, Swaziland, and Zambia) in the region. We subsequently inferred the potential contribution of each group to transmission using a simple model that builds on the results from the IPM and makes further assumptions about sexual mixing patterns and transmission rates. In all countries except Swaziland, individuals in unions were the single group contributing to the largest proportion of new infections acquired (39%-77%), followed by never married women and men. Female sex workers accounted for a large proportion of new infections (5%-16%) compared to their population size. Individuals in unions were also the single largest contributor to the proportion of infections transmitted (35%-62%), followed by key populations and previously married men and women. Swaziland exhibited different incidence patterns, with never married men and women accounting for over 65% of new infections acquired and also contributing to a large proportion of infections transmitted (up to 56%). Between- and within-country variations indicated different incidence patterns in specific settings. CONCLUSIONS It is possible to reliably predict the distribution of new HIV infections acquired using data routinely available in many countries in the sub-Saharan African region with a single relatively simple mathematical model. This tool would complement more specific analyses to guide resource allocation, data collection, and programme planning.
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Affiliation(s)
- Annick Bórquez
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
- Division of Global Public Health, University of California San Diego, San Diego, California, United States of America
- * E-mail:
| | - Anne Cori
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Erica L. Pufall
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | | | - Emma Slaymaker
- Department of Population Health, London School of Hygiene &Tropical Medicine, London, United Kingdom
| | - Alison Price
- Department of Population Health, London School of Hygiene &Tropical Medicine, London, United Kingdom
| | - Jocelyn Elmes
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Basia Zaba
- Department of Population Health, London School of Hygiene &Tropical Medicine, London, United Kingdom
| | - Amelia C. Crampin
- Department of Population Health, London School of Hygiene &Tropical Medicine, London, United Kingdom
| | | | - Tom Lutalo
- Rakai Health Sciences Program, Entebbe, Uganda
| | - Mark Urassa
- Mwanza Research Centre, National Institute for Medical Research, Mwanza, Tanzania
| | - Simon Gregson
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Timothy B. Hallett
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
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Taylor TM, Thurman TR, Nogela L. “Every time that month comes, I remember”:using cognitive interviews to adapt grief measures for use with bereaved adolescents in South Africa. J Child Adolesc Ment Health 2016; 28:163-74. [DOI: 10.2989/17280583.2016.1210154] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Concurrent partnerships in Cape Town, South Africa: race and sex differences in prevalence and duration of overlap. J Int AIDS Soc 2015; 18:19372. [PMID: 25697328 PMCID: PMC4334769 DOI: 10.7448/ias.18.1.19372] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 11/19/2014] [Accepted: 01/13/2015] [Indexed: 01/02/2023] Open
Abstract
Introduction Concurrent partnerships (CPs) have been suggested as a risk factor for transmitting HIV, but their impact on the epidemic depends upon how prevalent they are in populations, the average number of CPs an individual has and the length of time they overlap. However, estimates of prevalence of CPs in Southern Africa vary widely, and the duration of overlap in these relationships is poorly documented. We aim to characterize concurrency in a more accurate and complete manner, using data from three disadvantaged communities of Cape Town, South Africa. Methods We conducted a sexual behaviour survey (n=878) from June 2011 to February 2012 in Cape Town, using Audio Computer-Assisted Self-Interviewing to collect sexual relationship histories on partners in the past year. Using the beginning and end dates for the partnerships, we calculated the point prevalence, the cumulative prevalence and the incidence rate of CPs, as well as the duration of overlap for relationships begun in the previous year. Linear and binomial regression models were used to quantify race (black vs. coloured) and sex differences in the duration of overlap and relative risk of having CPs in the past year. Results The overall point prevalence of CPs six months before the survey was 8.4%: 13.4% for black men, 1.9% for coloured men, 7.8% black women and 5.6% for coloured women. The median duration of overlap in CPs was 7.5 weeks. Women had less risk of CPs in the previous year than men (RR 0.43; 95% CI: 0.32–0.57) and black participants were more at risk than coloured participants (RR 1.86; 95% CI: 1.17–2.97). Conclusions Our results indicate that in this population the prevalence of CPs is relatively high and is characterized by overlaps of long duration, implying there may be opportunities for HIV to be transmitted to concurrent partners.
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Chima Anyanwu F, Ter Goon D, Tugli A, Olukoga A, O Amusa L, Netshikweta ML, Ajao B. Perception of susceptibility to the negative outcomes associated with unprotected sex among University of Venda students. Pak J Med Sci 2014; 29:1306-10. [PMID: 24550942 PMCID: PMC3905366 DOI: 10.12669/pjms.296.4111] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 08/06/2013] [Accepted: 09/25/2013] [Indexed: 11/15/2022] Open
Abstract
Objectives: The purpose of this study was to determine the perception of University of Venda students on their susceptibility to the negative outcomes associated with unprotected sex. Methods: This cross sectional study involved 408 (206 females and 202 males) University of Venda students residing within the university campus. Simple and systematic sampling methods were used to select participants. A 4-likert scaled self-administered questionnaire was used for data collection and a cut-off point of 75% of the total scores was used as criteria for assessing perception. Results: Majority (90.90%) of the participants understood the magnitude and problems posed by HIV and other sexually transmitted infection in the society, 94.60% believe that anyone can be infected with HIV or fall pregnant when exposed to unprotected sex. Majority (87.30%) believed that alcohol consumption while engaging in sexual activities increases the chances of being infected with HIV, other STI or falling pregnant, 92.40% believed that having multiple sexual partnerships increases the risk of being infected with HIV and other sexually transmitted infections. Eighty six percent of participants agreed or strongly agreed that pregnancy could occur with one sexual intercourse in a month and only 68.45% of the participants believed that practising oral sex could expose them to HIV infection (with no significant difference between male and female). Conclusion: Majority of the students showed high perception regarding their susceptibility to the negative outcomes associated with unprotected sex, especially when they consume alcohol while engaging in sexual activities and when having multiple sexual partnerships. Contrastingly, the students demonstrated low perception regarding susceptibility to HIV transmission through the practice of oral sex. There is a need to create awareness on the dangers posed by the practise of oral sex.
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Affiliation(s)
- Felix Chima Anyanwu
- Felix Chima Anyanwu, Department of Public Health, University of Venda, Thohoyandou, South Africa
| | - Daniel Ter Goon
- Daniel Ter Goon, Centre for Biokinetics, Recreation and Sport Science, University of Venda, Thohoyandou, South Africa
| | - Augustine Tugli
- Augustine Tugli, Department of Public Health, University of Venda, Thohoyandou, South Africa
| | - Abiodun Olukoga
- Abiodun Olukoga, Department of Public Health, University of Venda, Thohoyandou, South Africa
| | - Lateef O Amusa
- Lateef O Amusa, Centre for Biokinetics, Recreation and Sport Science, University of Venda, Thohoyandou, South Africa
| | - M Lizzy Netshikweta
- Lizzy Department of Advanced Nursing, University of Venda, Thohoyandou, South Africa
| | - Babajide Ajao
- Babajide Department of Public Health, University of Venda, Thohoyandou, South Africa
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Beauclair R, Delva W. Is younger really safer? A qualitative study of perceived risks and benefits of age-disparate relationships among women in Cape Town, South Africa. PLoS One 2013; 8:e81748. [PMID: 24260585 PMCID: PMC3829971 DOI: 10.1371/journal.pone.0081748] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 10/16/2013] [Indexed: 11/18/2022] Open
Abstract
Young women in age-asymmetric relationships may be at an elevated risk for acquisition of HIV, since relationships with older men are also correlated with other risk behaviors like less condom use. Qualitative studies have shown that women are motivated to participate in these relationships for money and emotional support. However, there is a paucity of research on women’s perceived risks of these relationships, particularly in South Africa. To this end, we conducted in-depth interviews with 23 women recruited from three urban communities in Cape Town. A thematic question guide was used to direct the interviews. Thematic content analysis was used to explore women’s perceived risks of age-disparate and non-age-disparate relationships, the benefits of dating older men, and risk perceptions that influence decisions around beginning or ending a relationship. A plurality of women thought that dating an older man does not bring any adverse consequences, although some thought that older men do not use condoms and may be involved in concurrent partnerships. Many women were less inclined to date same-age or younger men, because they were viewed as being disrespectful and abusive. This study points to the need for more awareness raising about the risks of age-disparate relationships. In addition to these initiatives, there is an urgent need to implement holistic approaches to relationship health, in order to curb intimate partner violence, improve gender equity and make non-age-disparate relationships more attractive.
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Affiliation(s)
- Roxanne Beauclair
- The South African Department of Science and Technology/National Research Foundation (DST/NRF) Centre of Excellence in Epidemiological Modeling and Analysis (SACEMA), Stellenbosch University, Stellenbosch, South Africa
- * E-mail:
| | - Wim Delva
- The South African Department of Science and Technology/National Research Foundation (DST/NRF) Centre of Excellence in Epidemiological Modeling and Analysis (SACEMA), Stellenbosch University, Stellenbosch, South Africa
- International Centre for Reproductive Health, Ghent University, Gent, Belgium
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Coital frequency and condom use in monogamous and concurrent sexual relationships in Cape Town, South Africa. J Int AIDS Soc 2013; 16:18034. [PMID: 23618365 PMCID: PMC3636421 DOI: 10.7448/ias.16.1.18034] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 02/01/2013] [Accepted: 02/27/2013] [Indexed: 01/11/2023] Open
Abstract
Introduction A decreased frequency of unprotected sex during episodes of concurrent relationships may dramatically reduce the role of concurrency in accelerating the spread of HIV. Such a decrease could be the result of coital dilution – the reduction in per-partner coital frequency from additional partners – and/or increased condom use during concurrency. To study the effect of concurrency on the frequency of unprotected sex, we examined sexual behaviour data from three communities with high HIV prevalence around Cape Town, South Africa. Methods We conducted a cross-sectional survey from June 2011 to February 2012 using audio computer-assisted self-interviewing to reconstruct one-year sexual histories, with a focus on coital frequency and condom use. Participants were randomly sampled from a previous TB and HIV prevalence survey. Mixed effects logistic and Poisson regression models were fitted to data from 527 sexually active adults reporting on 1210 relationship episodes to evaluate the effect of concurrency status on consistent condom use and coital frequency. Results The median of the per-partner weekly average coital frequency was 2 (IQR: 1–3), and consistent condom use was reported for 36% of the relationship episodes. Neither per-partner coital frequency nor consistent condom use changed significantly during episodes of concurrency (aIRR=1.05; 95% confidence interval (CI): 0.99–1.24 and aOR=1.01; 95% CI: 0.38–2.68, respectively). Being male, coloured, having a tertiary education, and having a relationship between 2 weeks and 9 months were associated with higher coital frequencies. Being coloured, and having a relationship lasting for more than 9 months, was associated with inconsistent condom use. Conclusions We found no evidence for coital dilution or for increased condom use during concurrent relationship episodes in three communities around Cape Town with high HIV prevalence. Given the low levels of self-reported consistent condom use, our findings suggest that if the frequency of unprotected sex with each of the sexual partners is sustained during concurrent relationships, HIV-positive individuals with concurrent partners may disproportionately contribute to onward HIV transmission.
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Beauclair R, Meng F, Deprez N, Temmerman M, Welte A, Hens N, Delva W. Evaluating audio computer assisted self-interviews in urban South African communities: evidence for good suitability and reduced social desirability bias of a cross-sectional survey on sexual behaviour. BMC Med Res Methodol 2013; 13:11. [PMID: 23368888 PMCID: PMC3568408 DOI: 10.1186/1471-2288-13-11] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 01/25/2013] [Indexed: 11/24/2022] Open
Abstract
Background Efficient HIV prevention requires accurate identification of individuals with risky sexual behaviour. However, self-reported data from sexual behaviour surveys are prone to social desirability bias (SDB). Audio Computer-Assisted Self-Interviewing (ACASI) has been suggested as an alternative to face-to-face interviewing (FTFI), because it may promote interview privacy and reduce SDB. However, little is known about the suitability and accuracy of ACASI in urban communities with high HIV prevalence in South Africa. To test this, we conducted a sexual behaviour survey in Cape Town, South Africa, using ACASI methods. Methods Participants (n = 878) answered questions about their sexual relationships on a touch screen computer in a private mobile office. We included questions at the end of the ACASI survey that were used to assess participants’ perceived ease of use, privacy, and truthfulness. Univariate logistic regression models, supported by multivariate models, were applied to identify groups of people who had adverse interviewing experiences. Further, we constructed male–female ratios of self-reported sexual behaviours as indicators of SDB. We used these indicators to compare SDB in our survey and in recent FTFI-based Demographic and Health Surveys (DHSs) from Lesotho, Swaziland, and Zimbabwe. Results Most participants found our methods easy to use (85.9%), perceived privacy (96.3%) and preferred ACASI to other modes of inquiry (82.5%) when reporting on sexual behaviours. Unemployed participants and those in the 40–70 year old age group were the least likely to find our methods easy to use (OR 0.69; 95% CI: 0.47–1.01 and OR 0.37; 95% CI: 0.23–0.58, respectively). In our survey, the male–female ratio for reporting >2 sexual partners in the past year, a concurrent relationship in the past year, and > 2 sexual partners in a lifetime was 3.4, 2.6, and 1.2, respectively— far lower than the ratios observed in the Demographic and Health Surveys. Conclusions Our analysis suggests that most participants in our survey found the ACASI modality to be acceptable, private, and user-friendly. Moreover, our results indicate lower SDB than in FTFI techniques. Targeting older and unemployed participants for ACASI training prior to taking the survey may help to improve their perception of ease and privacy.
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Affiliation(s)
- Roxanne Beauclair
- The South African Department of Science and Technology/National Research Foundation (DST/NRF) Centre of Excellence in Epidemiological Modelling and Analysis (SACEMA), Stellenbosch University, 19 Jonkershoek Road, Stellenbosch 7600, South Africa.
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Beauclair R, Kassanjee R, Temmerman M, Welte A, Delva W. Age-disparate relationships and implications for STI transmission among young adults in Cape Town, South Africa. EUR J CONTRACEP REPR 2012; 17:30-9. [PMID: 22239263 DOI: 10.3109/13625187.2011.644841] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVES To estimate the prevalence of age-disparate (AD) relationships among young black and coloured adults in Cape Town (South Africa) and determine socio-demographic predictors and individual and relationship characteristics of women in these relationships. METHODS A secondary analysis of the Cape Area Panel Study (N = 1960) data was conducted. Descriptive statistics were used to quantify the age-mixing pattern and logistic regression was used to identify significant socio-demographic and behavioural correlates of AD relationships. RESULTS Prevalence of AD relationships was high in both black (36%) and coloured (28%) women. The average age difference between male respondents and their partners increased with age. Young, black women who spent fewer nights under the same roof in one week, had a deceased parent, and were not currently attending classes were more likely to be in an AD relationship. Reports of sexually-transmitted infection (STI) symptoms in the last month and unprotected sex were more common among women in AD relationships. CONCLUSIONS AD relationships are common among young women in Cape Town. Home and family stability is preventative of young women engaging in AD relationships. Therefore, holistic, societal interventions may reduce AD relationships, which are a risk factor for STIs.
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Affiliation(s)
- Roxanne Beauclair
- South African Centre for Epidemiological Modelling & Analysis, Stellenbosch University, South Africa.
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