Browsing by Author "Delva, Wim"

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    Age differences between sexual partners, behavioural and demographic correlates, and HIV infection on Likoma Island, Malawi
    (Springer Nature, 2016) Beauclair, Roxanne; Helleringe, Stephane; Hens, Niel; Delva, Wim
    Patterns of age differences between sexual partners – age-mixing – may partially explain the magnitude of HIV epidemics in Sub-Saharan Africa. However, evidence of age-disparity as a risk factor for HIV remains mixed. We used data from a socio-centric study of sexual behaviour in Malawi to quantify the age-mixing pattern and to find associations between relationship characteristics and age differences for 1,922 participants. Three age difference measures were explored as predictors of prevalent HIV infection. We found that for each year increase in male participant age, the average age difference with their partners increased by 0.26 years, while among women it remained approximately constant around 5 years. Women in the study had larger within-individual variation in partner ages compared to men. Spousal partnerships and never using a condom during sex were associated with larger age differences in relationships of both men and women. Men who were more than five years younger than their partners had 5.39 times higher odds (95% CI: 0.93–31.24) of being HIV-infected than men 0–4 years older. The relationship between HIV-infection and age-asymmetry may be more complex than previously described. The role that women play in HIV transmission should not be under-estimated, particularly in populations with large within-individual variation in partner ages.
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    Age-disparity, sexual connectedness and HIV infection in disadvantaged communities around Cape Town, South Africa: A study protocol
    (BioMed Central Ltd, 2011) Delva, Wim; Beauclair, Roxanne; Welte, Alex; Vansteelandt, Stijn; Hens, Niel; Aerts, Marc; Du Toit, Elizabeth; Beyers, Nulda; Temmerman, Marleen
    Abstract: Background Crucial connections between sexual network structure and the distribution of HIV remain inadequately understood, especially in regard to the role of concurrency and age disparity in relationships, and how these network characteristics correlate with each other and other risk factors. Social desirability bias and inaccurate recall are obstacles to obtaining valid, detailed information about sexual behaviour and relationship histories. Therefore, this study aims to use novel research methods in order to determine whether HIV status is associated with age-disparity and sexual connectedness as well as establish the primary behavioural and socio-demographic predictors of the egocentric and community sexual network structures. Method/Design We will conduct a cross-sectional survey that uses a questionnaire exploring one-year sexual histories, with a focus on timing and age disparity of relationships, as well as other risk factors such as unprotected intercourse and the use of alcohol and recreational drugs. The questionnaire will be administered in a safe and confidential mobile interview space, using audio computer-assisted self-interview (ACASI) technology on touch screen computers. The ACASI features a choice of languages and visual feedback of temporal information. The survey will be administered in three peri-urban disadvantaged communities in the greater Cape Town area with a high burden of HIV. The study communities participated in a previous TB/HIV study, from which HIV test results will be anonymously linked to the survey dataset. Statistical analyses of the data will include descriptive statistics, linear mixed-effects models for the inter- and intra-subject variability in the age difference between sexual partners, survival analysis for correlated event times to model concurrency patterns, and logistic regression for association of HIV status with age disparity and sexual connectedness. Discussion This study design is intended to facilitate more accurate recall of sensitive sexual history data and has the potential to provide substantial insights into the relationship between key sexual network attributes and additional risk factors for HIV infection. This will help to inform the design of context-specific HIV prevention programmes.
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    Are HIV and reproductive health services adapted to the needs of female sex workers? results of a policy and situational analysis in Tete, Mozambique
    (BioMed Central, 2016) Lafort, Yves; Jocitala, Osvaldo; Candrinho, Balthazar; Greener, Letitia; Beksinska, Mags; Smit, Jenni A.; Chersich, Matthew; Delva, Wim
    Background In the context of an implementation research project aiming at improving use of HIV and sexual and reproductive health (SRH) services for female sex workers (FSWs), a broad situational analysis was conducted in Tete, Mozambique, assessing if services are adapted to the needs of FSWs. Methods Methods comprised (1) a policy analysis including a review of national guidelines and interviews with policy makers, and (2) health facility assessments at 6 public and 1 private health facilities, and 1 clinic specifically targeting FSWs, consisting of an audit checklist, interviews with 18 HIV/SRH care providers and interviews of 99 HIV/SRH care users. Results There exist national guidelines for most HIV/SRH care services, but none provides guidance for care adapted to the needs of high-risk women such as FSWs. The Ministry of Health recently initiated the process of establishing guidelines for attendance of key populations, including FSWs, at public health facilities. Policy makers have different views on the best approach for providing services to FSWs—integrated in the general health services or through parallel services for key populations—and there exists no national strategy. The most important provider of HIV/SRH services in the study area is the government. Most basic services are widely available, with the exception of certain family planning methods, cervical cancer screening, services for victims of sexual and gender-based violence, and termination of pregnancy (TOP). The public facilities face serious limitations in term of space, staff, equipment, regular supplies and adequate provider practices. A stand-alone clinic targeting key populations offers a limited range of services to the FSW population in part of the area. Private clinics offer only a few services, at commercial prices. Conclusion There is a need to improve the availability of quality HIV/SRH services in general and to FSWs specifically, and to develop guidelines for care adapted to the needs of FSWs. Access for FSWs can be improved by either expanding the range of services and the coverage of the targeted clinic and/or by improving access to adapted care at the public health services and ensure a minimum standard of quality.
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    Assessing the uncertainty around age-mixing patterns in HIV transmission inferred from phylogenetic trees
    (Public Library of Science, 2021) Niyukuri, David; Nyasulu, Peter S.; Delva, Wim
    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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    Barriers to HIV and sexual and reproductive health care for female sex workers in Tete, Mozambique : results from a cross-sectional survey and focus group discussions
    (BioMed Central, 2016) Lafort, Yves; Lessitala, Faustino; Candrinho, Balthazar; Greener, Letitia; Greener, Ross; Beksinska, Mags; Smit, Jenni A.; Chersich, Matthew; Delva, Wim
    Background: In the context of an operational research project in Tete, Mozambique, use of, and barriers to, HIV and sexual and reproductive health (HIV/SRH) commodities and services for female sex workers (FSWs) were assessed as part of a baseline situational analysis. Methods: In a cross-sectional survey 311 FSWs were recruited using respondent driven sampling and interviewed face-to-face, and three focus group discussions were held with respectively 6 full-time Mozambican, 7 occasional Mozambican and 9 full-time Zimbabwean FSWs, to investigate use of, and barriers to, HIV/SRH care. Results: The cross-sectional survey showed that 71 % of FSWs used non-barrier contraception, 78 % sought care for their last sexually transmitted infection episode, 51 % of HIV-negative FSWs was tested for HIV in the last 6 months, 83 % of HIV-positive FSWs were in HIV care, 55 % sought help at a health facility for their last unwanted pregnancy and 48 % after sexual assault, and none was ever screened for cervical cancer. Local public health facilities were by far the most common place where care was sought, followed by an NGO-operated clinic targeting FSWs, and places outside the Tete area. In the focus group discussions, FSWs expressed dissatisfaction with the public health services, as a result of being asked for bribes, being badly attended by some care providers, stigmatisation and breaches of confidentiality. The service most lacking was said to be termination of unwanted pregnancies. Conclusions: The use of most HIV and SRH services is insufficient in this FSW population. The public health sector is the main provider, but access is hampered by several barriers. The reach of a FSW-specific NGO clinic is limited. Access to, and use of, HIV and SRH services should be improved by reducing barriers at public health facilities, broadening the range of services and expanding the reach of the targeted NGO clinic.
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    Barriers to VCT despite 13 years of community-based awareness campaigns in a peri-urban township in northern Limpopo
    (Health and Medical Publishing Group (HMPG), 2010) De Koker, Petra; Lefevre, Pierre; Matthys, Francine; Van der Stuyft, Patrick; Delva, Wim
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    Beyond risk compensation : clusters of antiretroviral treatment (ART) users in sexual networks can modify the impact of ART on HIV incidence
    (Public Library of Science, 2016) Delva, Wim; Helleringer, Stephane
    Introduction: Concerns about risk compensation—increased risk behaviours in response to a perception of reduced HIV transmission risk—after the initiation of ART have largely been dispelled in empirical studies, but other changes in sexual networking patterns may still modify the effects of ART on HIV incidence. Methods: We developed an exploratory mathematical model of HIV transmission that incorporates the possibility of ART clusters, i.e. subsets of the sexual network in which the density of ART patients is much higher than in the rest of the network. Such clusters may emerge as a result of ART homophily—a tendency for ART patients to preferentially form and maintain relationships with other ART patients. We assessed whether ART clusters may affect the impact of ART on HIV incidence, and how the influence of this effect-modifying variable depends on contextual variables such as HIV prevalence, HIV serosorting, coverage of HIV testing and ART, and adherence to ART. Results: ART homophily can modify the impact of ART on HIV incidence in both directions. In concentrated epidemics and generalized epidemics with moderate HIV prevalence (≈ 10%), ART clusters can enhance the impact of ART on HIV incidence, especially when adherence to ART is poor. In hyperendemic settings (≈ 35% HIV prevalence), ART clusters can reduce the impact of ART on HIV incidence when adherence to ART is high but few people living with HIV (PLWH) have been diagnosed. In all contexts, the effects of ART clusters on HIV epidemic dynamics are distinct from those of HIV serosorting. Conclusions: Depending on the programmatic and epidemiological context, ART clusters may enhance or reduce the impact of ART on HIV incidence, in contrast to serosorting, which always leads to a lower impact of ART on HIV incidence. ART homophily and the emergence of ART clusters should be measured empirically and incorporated into more refined models used to plan and evaluate ART programmes.
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    Community assault and non-community assault among adults in Khayelitsha: A case count and comparison of injury severity
    (Stellenbosch : Stellenbosch University, 2015-07) Forgus, Sheron; Delva, Wim; Hauptfleisch, Christine; Govender, Srini; Blitz, Julia; Stellenbosch University. Faculty of Health Sciences. Dept. of Interdisciplinary Health Sciences
    ENGLISH ABSTRACT: Background: Community Assault (CA) or vigilantism is rife in the township of Khayelitsha. Anecdotal evidence suggests that victims of CA are worse off than other assault cases. However, scientific data on the rate and severity of CA cases is lacking for South Africa. Aims and Objectives: To contribute to CA prevention and management strategies, by estimating the rate of CA among adults in Khayelitsha and comparing the injury severity and survival probability between cases of CA and other assault (non-CA) cases. Methods: We studied 4 health centres in Khayelitsha during July - December 2012. A consecutive case-series was conducted to capture all CA cases during this period and a retrospective folder review was performed on all cases of CA as well as on a control group of non-CA cases to compare injury severity and estimate survival probability. Results: One hundred and forty-eight adult cases of CA occurred (case rate 1.1/1000 person-years) over the study period. The Injury Severity Scores (ISS) in the CA group were significantly higher than in the non-CA group (P<0.001), with a median (Inter Quartile Range) ISS of 3 in CA cases (2-6) and 1 in non-CA cases (1-2). Comparison between the two groups showed that a GCS<15 (20.1% versus 5.4%), referral to the tertiary hospital (33.8% versus 22.6%), and crush syndrome (25.7% versus 0%) were all more common in CA cases. Survival probabilities were similar in both groups: 99.2% in the CA group versus 99.3% in the non-CA group. Conclusion: The rate of CA among adults in Khayelitsha is high, and the severity of injuries sustained by CA victims is substantially higher than in other assault cases.
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    Community v. non-community assault among adults in Khayelitsha, Western Cape, South Africa : a case count and comparison of injury severity
    (Health & Medical Publishing Group, 2014-04) Forgus, Sheron; Delva, Wim; Hauptfleisch, Christine; Govender, Srinivasan; Blitz, Julia
    Background. Community assault (CA) or vigilantism is widespread in the township of Khayelitsha, Cape Town, South Africa (SA). Anecdotal evidence suggests that victims of CA are worse off than other assault cases. However, scientific data on the rate and severity of CA cases are lacking for SA. Objectives. To contribute to CA prevention and management strategies by estimating the rate of CA among adults in Khayelitsha and comparing the injury severity and survival probability between cases of CA and other assault (non-CA) cases. Methods. We studied four healthcare centres in Khayelitsha during July - December 2012. A consecutive case series was conducted to capture all CA cases during this period. A retrospective folder review was performed on all cases of CA and on a control group of non-CA cases to compare injury severity and estimate survival probability. Results. A total of 148 adult cases of CA occurred (case rate 1.1/1 000 person-years) over the study period. The Injury Severity Scores (ISSs) in the CA group were significantly higher than in the non-CA group (p<0.001), with a median (interquartile range) ISS of 3 (2 - 6) in CA cases v. 1 (1 - 2) in non-CA cases. Comparison between the CA v. non-CA groups showed that a Glasgow Coma Scale <15 (20.1% v. 5.4%, respectively), referral to the tertiary hospital (33.8% v. 22.6%, respectively), and crush syndrome (25.7% v. 0.0%, respectively) were all more common in CA cases. Survival probabilities were similar in both groups (CA v. non-CA 99.2% v. 99.3%, respectively). Conclusion. The rate of CA among adults in Khayelitsha is high, and the severity of injuries sustained by CA victims is substantially higher than in other assault cases.
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    Comparison of two simulators for individual based models in HIV epidemiology in a population with HSV 2 in Yaounde (Cameroon)
    (Nature, 2021-07) Hendrickx, Diana M.; Sousa, Joao Dinis; Libin, Pieter J. K.; Delva, Wim; Liesenborgs, Jori; Hens, Niel; Muller, Viktor; Vandamme, Anne-Mieke
    Model comparisons have been widely used to guide intervention strategies to control infectious diseases. Agreement between different models is crucial for providing robust evidence for policy-makers because differences in model properties can influence their predictions. In this study, we compared models implemented by two individual-based model simulators for HIV epidemiology in a heterosexual population with Herpes simplex virus type-2 (HSV-2). For each model simulator, we constructed four models, starting from a simplified basic model and stepwise including more model complexity. For the resulting eight models, the predictions of the impact of behavioural interventions on the HIV epidemic in Yaoundé-Cameroon were compared. The results show that differences in model assumptions and model complexity can influence the size of the predicted impact of the intervention, as well as the predicted qualitative behaviour of the HIV epidemic after the intervention. These differences in predictions of an intervention were also observed for two models that agreed in their predictions of the HIV epidemic in the absence of that intervention. Without additional data, it is impossible to determine which of these two models is the most reliable. These findings highlight the importance of making more data available for the calibration and validation of epidemiological models.
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    Concurrent partnerships in Cape Town, South Africa : race and sex differences in prevalence and duration of overlap
    (International AIDS Society, 2015-02) Beauclair, Roxanne; Hens, Niel; Delva, Wim
    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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    Differential sexual network connectivity offers a parsimonious explanation for population-level variations in the prevalence of bacterial vaginosis: a data-driven, model-supported hypothesis
    (BMC (part of Springer Nature), 2019-01-10) Kenyon, Chris R.; Delva, Wim; Brotman, Rebecca M.
    Background: The prevalence of bacterial vaginosis (BV) and vaginal microbiota types varies dramatically between different populations around the world. Understanding what underpins these differences is important, as highdiversity microbiotas associated with BV are implicated in adverse pregnancy outcomes and enhanced susceptibility to and transmission of sexually transmitted infections. Main text: We hypothesize that these variations in the vaginal microbiota can, in part, be explained by variations in the connectivity of sexual networks. We argue: 1) Couple-level data suggest that BV-associated bacteria can be sexually transmitted and hence high sexual network connectivity would be expected to promote the spread of BVassociated bacteria. Epidemiological studies have found positive associations between indicators of network connectivity and the prevalence of BV; 2) The relationship between BV prevalence and STI incidence/prevalence can be parsimoniously explained by differential network connectivity; 3) Studies from other mammals are generally supportive of the association between network connectivity and high-diversity vaginal microbiota. Conclusion: To test this hypothesis, we propose a combination of empirical and simulation-based study designs.
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    The effect of sexually transmitted co-infections on HIV viral load amongst individuals on antiretroviral therapy : a systematic review and meta-analysis
    (BioMed Central, 2015-06) Champredon, David; Bellan, Steven E.; Delva, Wim; Hunt, Spencer; Shi, Chyun-Fung; Smieja, Marek; Dushoff, Jonathan
    Background: Antiretroviral therapy (ART) markedly reduces HIV transmission, and testing and treatment programs have been advocated as a method for decreasing transmission at the population level. Little is known, however, about the extent to which sexually transmitted infections (STIs), which increase the HIV infectiousness of untreated individuals, may decrease the effectiveness of treatment as prevention. Methods: We searched major bibliographic databases to August 12th, 2014 and identified studies reporting differences in HIV transmission rate or in viral load between individuals on ART who either were or were not co-infected with another STI. We used hierarchical Bayesian models to estimate viral load differences between individuals with and without STI co-infections. Results: The search strategy retrieved 1630 unique citations of which 14 studies (reporting on 4607 HIV viral load measurements from 2835 unique individuals) met the inclusion criteria. We did not find any suitable studies that estimated transmission rates directly in both groups. Our meta-analysis of HIV viral load measurements among treated individuals did not find a statistically significant effect of STI co-infection; viral loads were, on average, 0.11 log10 (95 % CI −0.62 to 0.83) higher among co-infected versus non-co-infected individuals. Conclusions: Direct evidence about the effects of STI co-infection on transmission from individuals on ART is very limited. Available data suggests that the average effect of STI co-infection on HIV viral load in individuals on ART is less than 1 log10 difference, and thus unlikely to decrease the effectiveness of treatment as prevention. However, there is not enough data to rule out the possibility that particular STIs pose a larger threat.
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    Effectiveness of a peer-led HIV prevention intervention in secondary schools in Rwanda : results from a non-randomized controlled trial
    (BioMed Central, 2012-09) Michielsen, Kristien; Beauclair, Roxanne; Delva, Wim; Roelens, Kristien; Van Rossem, Ronan; Temmerman, Marleen
    While the HIV epidemic is levelling off in sub-Saharan Africa, it remains at an unacceptably high level. Young people aged 15-24 years remain particularly vulnerable, resulting in a regional HIV prevalence of 1.4% in young men and 3.3% in young women. This study assesses the effectiveness of a peer-led HIV prevention intervention in secondary schools in Rwanda on young people's sexual behavior, HIV knowledge and attitudes.
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    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
    (BioMed Central, 2013-01) Beauclair, Roxanne; Meng, Fei; Deprez, Nele; Temmerman, Marleen; Welte, Alex; Hens, Niel; Delva, Wim
    Abstract: 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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    Feasibility, acceptability and potential sustainability of a ‘diagonal’ approach to health services for female sex workers in Mozambique
    (BMC (part of Springer Nature), 2018-10-03) Lafort, Yves; Ismael de Melo, Malica S.; Lessitala, Faustino; Griffin, Sally; Chersich, Matthew; Delva, Wim
    Background: Female sex workers (FSWs) in many settings have restricted access to sexual and reproductive health (SRH) services. We therefore conducted an implementation study to test a ‘diagonal’ intervention which combined strengthening of FSW-targeted services (vertical) with making public health facilities more FSW-friendly (horizontal). We piloted it over 18 months and then assessed its performance. Methods: Applying a convergent parallel mixed-methods design, we triangulated the results of the analysis of process indicators, semi-structured interviews with policy makers and health managers, structured interviews with health care providers and group discussions with peer outreach workers. We then formulated integrated conclusions on the interventions’ feasibility, acceptability by providers, managers and policy makers, and potential sustainability. Results: The intervention, as designed, was considered theoretically feasible by all informants, but in practice the expansion of some of the targeted services was hampered by insufficient financial resources, institutional capacity and buy-in from local government and private partners, and could not be fully actualised. In terms of acceptability, there was broad consensus on the need to ensure FSWs have access to SRH services, but not on how this might be achieved. Targeted clinical services were no longer endorsed by national government, which now prefers a strategy of making public services more friendly for key populations. Stakeholders judged that the piloted model was not fully sustainable, nor replicable elsewhere in the country, given its dependency on short-term project-based funding, lack of government endorsement for targeted clinical services, and viewing the provision of community activities as a responsibility of civil society. Conclusions: In the current Mozambican context, a ‘diagonal’ approach to ensure adequate access to sexual and reproductive health care for female sex workers is not fully feasible, acceptable or sustainable, because of insufficient resources and lack of endorsement by national policy makers for the targeted, vertical component.
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    HIV treatment as prevention : optimising the impact of expanded HIV treatment programmes
    (Public Library of Science (PLOS), 2012-07) Delva, Wim; Eaton, Jeffrey W.; Meng, Fei; Fraser, Christophe; White, Richard G.; Vickerman, Peter; Boily, Marie-Claude; Hallett, Timothy B.
    Until now, decisions about how to allocate ART have largely been based on maximising the therapeutic benefit of ART for patients. Since the results of the HPTN 052 study showed efficacy of antiretroviral therapy (ART) in preventing HIV transmission, there has been increased interest in the benefits of ART not only as treatment, but also in prevention. Resources for expanding ART in the short term may be limited, so the question is how to generate the most prevention benefit from realistic potential increases in the availability of ART. Although not a formal systematic review, here we review different ways in which access to ART could be expanded by prioritising access to particular groups based on clinical or behavioural factors. For each group we consider (i) the clinical and epidemiological benefits, (ii) the potential feasibility, acceptability, and equity, and (iii) the affordability and cost-effectiveness of prioritising ART access for that group. In re-evaluating the allocation of ART in light of the new data about ART preventing transmission, the goal should be to create policies that maximise epidemiological and clinical benefit while still being feasible, affordable, acceptable, and equitable.
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    HIV treatment as prevention : principles of good HIV epidemiology modelling for public health decision- making in all modes of prevention and evaluation
    (Public Library of Science (PLOS), 2012-07) Delva, Wim; Wilson, David P.; Abu-Raddad, Laith; Gorgens, Marelize; Wilson, David; Hallett, Timothy B.; Welte, Alex
    Public health responses to HIV epidemics have long relied on epidemiological modelling analyses to help prospectively project and retrospectively estimate the impact, cost-effectiveness, affordability, and investment returns of interventions, and to help plan the design of evaluations. But translating model output into policy decisions and implementation on the ground is challenged by the differences in background and expectations of modellers and decision-makers. As part of the PLoS Medicine Collection ‘‘Investigating the Impact of Treatment on New HIV Infections’’—which focuses on the contribution of modelling to current issues in HIV prevention—we present here principles of ‘‘best practice’’ for the construction, reporting, and interpretation of HIV epidemiological models for public health decision-making on all aspects of HIV. Aimed at both those who conduct modelling research and those who use modelling results, we hope that the principles described here will become a shared resource that facilitates constructive discussions about the policy implications that emerge from HIV epidemiology modelling results, and that promotes joint understanding between modellers and decision-makers about when modelling is useful as a tool in quantifying HIV epidemiological outcomes and improving prevention programming.
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    Impact of a diagonal intervention on uptake of sexual and reproductive health services by female sex workers in Mozambique : a mixed-methods implementation study
    (Frontiers Media, 2018) Lafort, Yves; Lessitala, Faustino; De Melo, Malica Sofia Ismael; Griffin, Sally; Chersich, Matthew; Delva, Wim
    Background: Female sex workers (FSWs) have high risks for adverse sexual and reproductive health (SRH) outcomes, yet low access to services. Within an implementation research project enhancing uptake of SRH services by FSWs, we piloted a “diagonal” intervention, which combined strengthening of FSW-targeted services (vertical) with making public health facilities more FSW-friendly (horizontal), and tested its effect. Methods: The study applied a convergent parallel mixed-methods design to assess changes in access to SRH services. Results of structured interviews with FSWs pre-intervention (N = 311) and thereafter (N = 404) were compared with the findings of eight post-intervention focus group discussions (FGDs) with FSWs and two with FSW-peer educators (PEs). Results: Marked and statistically significant rises occurred in consistent condom use with all partners (55.3–67.7%), ever use of female condoms (37.9–54.5%), being tested for HIV in the past 6 months (56.0–76.6%), using contraception (84.5–95.4%), ever screened for cervical cancer (0.0–16.9%) and having ≥10 contacts with a PE in the past year (0.5–24.45%). Increases mostly resulted from FSW-targeted outreach, with no rise detected in utilization of public health facilities. FGD participants reported that some facilities had become more FSW-friendly, but barriers such as stock-outs, being asked for bribes and disrespectful treatment persisted. Conclusion: The combination of expanding FSW-targeted SRH services with improving access to the public health services resulted in an overall increased uptake of services, but almost exclusively because of the strengthened targeted (vertical) outreach services. Utilization of public SRH services had not yet increased and many barriers to access remained. Our diagonal approach was thus only successful in its vertical component. Improving access to the general health services remains nevertheless important and further research is needed how to reduce barriers. Ideally, the combination approach should be maintained and more successful approaches to increase utilization of public services should be explored.
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    Impact of early initiation versus national standard of care of antiretroviral therapy in Swaziland’s public sector health system : study protocol for a stepped-wedge randomized trial
    (BMC (part of Springer Nature), 2017) Walsh, Fiona J.; Barnighausen, Till; Delva, Wim; Fleming, Yvette; Khumalo, Gavin; Lejeune, Charlotte L.; Mazibuko, Sikhathele; Mlambo, Charmaine Khudzie; Reis, Ria; Spiegelman, Donna; Zwane, Mandisa; Okello, Velephi
    Background: There is robust clinical evidence to support offering early access to antiretroviral treatment (ART) to all HIV-positive individuals, irrespective of disease stage, to both improve patient health outcomes and reduce HIV incidence. However, as the global treatment guidelines shift to meet this evidence, it is still largely unknown if early access to ART for all (also referred to as “treatment as prevention” or “universal test and treat”) is a feasible intervention in the resource-limited countries where this approach could have the biggest impact on the course of the HIV epidemics. The MaxART Early Access to ART for All (EAAA) implementation study was designed to determine the feasibility, acceptability, clinical outcomes, affordability, and scalability of offering early antiretroviral treatment to all HIV-positive individuals in Swaziland’s public sector health system. Methods: This is a three-year stepped-wedge randomized design with open enrollment for all adults aged 18 years and older across 14 government-managed health facilities in Swaziland’s Hhohho Region. Primary endpoints are retention and viral suppression. Secondary endpoints include ART initiation, adherence, drug resistance, tuberculosis, HIV disease progression, patient satisfaction, and cost per patient per year. Sites are grouped to transition two at a time from the control (standard of care) to intervention (EAAA) stage at each four-month step. This design will result in approximately one half of the total observation time to accrue in the intervention arm and the other half in the control arm. Our estimated enrolment number, which is supported by conservative power calculations, is 4501 patients over the course of the 36-month study period. A multidisciplinary, mixed-methods approach will be adopted to supplement the randomized controlled trial and meet the study aims. Additional study components include implementation science, social science, economic evaluation, and predictive HIV incidence modeling. Discussion: A stepped-wedge randomized design is a causally strong and robust approach to determine if providing antiretroviral treatment for all HIV-positive individuals is a feasible intervention in a resource-limited, public sector health system. We expect our study results to contribute to health policy decisions related to the HIV response in Swaziland and other countries in sub-Saharan Africa.