88 results found
Schaefer R, Gregson S, Eaton JW, et al., 2017, Age-disparate relationships and HIV incidence in adolescent girls and young women: evidence from a general-population cohort in Zimbabwe, AIDS, Vol: 31, Pages: 1461-1470, ISSN: 0269-9370
Objective: Age-disparate sexual relationships with older men may drive high rates of HIV acquisition in young women in sub-Saharan Africa but evidence is limited. We investigate the association between age-disparate relationships and HIV incidence in Manicaland, Zimbabwe.Design: A general-population open-cohort study (six surveys) (1998-2013).Methods: 3746 young women aged 15-24 years participated in consecutive surveys and were HIV-negative at the beginning of inter-survey periods. Last sexual partner age difference and age-disparate relationships (inter-generational [≥10 years age difference] and intra-generational [5-9 years] versus age-homogeneous [0-4 years]) were tested for associations with HIV incidence in Cox regressions. A proximate determinants framework was used to explore factors possibly explaining variations in the contribution of age-disparate relationships to HIV incidence between populations and over time.Results: 126 HIV infections occurred over 8777 person-years (1.43 per 100 person-years; 95% confidence interval=1.17-1.68). 65% of women reported partner age differences of ≥5 years. Increasing partner age differences were associated with higher HIV incidence (adjusted hazard ratio [aHR]=1.05 [1.01-1.09]). Inter-generational relationships tended to increase HIV incidence (aHR=1.78 [0.96-3.29]) but not intra-generational relationships (aHR=0.91 [0.47-1.76]). Secondary education was associated with reductions in inter-generational relationships (adjusted odds ratio [aOR]=0.49 [0.36-0.68]). Inter-generational relationships were associated with partners having concurrent relationships (aOR=2.59 [1.81-3.70]) which tended to increase HIV incidence (aHR=1.74 [0.96-3.17]). Associations between age-disparity and HIV incidence did not change over time.Conclusions: Sexual relationships with older men expose young women to increased risk of HIV acquisition in Manicaland, which did not change over time, even with introduction of antiretroviral therapy.
Mangal TD, UNAIDS Working Group on CD4 Progression and Mortality Amongst HIV Seroconverters including the CASCADE Collaboration in EuroCoord, 2017, Joint estimation of CD4+ cell progression and survival in untreated individuals with HIV-1 infection., AIDS, Vol: 31, Pages: 1073-1082, ISSN: 0269-9370
OBJECTIVE: We compiled the largest dataset of seroconverter cohorts to date from 25 countries across Africa, North America, Europe, and Southeast/East (SE/E) Asia to simultaneously estimate transition rates between CD4 cell stages and death, in antiretroviral therapy (ART)-naive HIV-1-infected individuals. DESIGN: A hidden Markov model incorporating a misclassification matrix was used to represent natural short-term fluctuations and measurement errors in CD4 cell counts. Covariates were included to estimate the transition rates and survival probabilities for each subgroup. RESULTS: The median follow-up time for 16 373 eligible individuals was 4.1 years (interquartile range 1.7-7.1), and the mean age at seroconversion was 31.1 years (SD 8.8). A total of 14 525 individuals had recorded CD4 cell counts pre-ART, 1885 died, and 6947 initiated ART. Median (interquartile range) survival for men aged 20 years at seroconversion was 13.0 (12.4-13.4), 11.6 (10.9-12.3), and 8.3 years (7.9-8.9) in Europe/North America, Africa, and SE/E Asia, respectively. Mortality rates increase with age (hazard ratio 2.22, 95% confidence interval 1.84-2.67 for >45 years compared with <25 years) and vary by region (hazard ratio 2.68, 1.75-4.12 for Africa and 1.88, 1.50-2.35 for Asia compared with Europe/North America). CD4 cell decline was significantly faster in Asian cohorts compared with Europe/North America (hazard ratio 1.45, 1.36-1.54). CONCLUSION: Mortality and CD4 cell progression rates exhibited regional and age-specific differences, with decreased survival in African and SE/E Asian cohorts compared with Europe/North America and in older age groups. This extensive dataset reveals heterogeneities between regions and ages, which should be incorporated into future HIV models.
Eaton JW, Johnson CC, Gregson S, 2017, The cost of not re-testing: HIV misdiagnosis in the ART ‘test-and-offer’ era, Clinical Infectious Diseases, Vol: 65, Pages: 522-525, ISSN: 1537-6591
We compared estimated costs of retesting human immunodeficiency virus (HIV)-positive persons before antiretroviral therapy (ART) initiation to the costs of ART provision to misdiagnosed HIV-negative persons. Savings from averted unnecessary ART costs were greater than retesting costs within 1 year using assumptions representative of HIV testing performance in programmatic settings. Countries should implement re-testing before ART initiation.
McRobie E, Wringe A, Nakiyingi-Miiro J, et al., 2017, HIV policy implementation in two health and demographic surveillance sites in Uganda: findings from a national policy review, health facility surveys, and key informant interviews, Implementation Science, Vol: 12, ISSN: 1748-5908
BackgroundSuccessful HIV testing, care and treatment policy implementation is essential for realising the reductions in morbidity and mortality those policies are designed to target. While adoption of new HIV policies is rapid, less is known about the facility-level implementation of new policies and the factors influencing this.MethodsWe assessed implementation of national policies about HIV testing, treatment and retention at health facilities serving two health and demographic surveillance sites (HDSS) (10 in Kyamulibwa, 14 in Rakai). Ugandan Ministry of Health HIV policy documents were reviewed in 2013, and pre-determined indicators were extracted relating to the content and nature of guidance on HIV service provision. Facility-level policy implementation was assessed via a structured questionnaire administered to in-charge staff from each health facility. Implementation of policies was classified as wide (≥75% facilities), partial (26–74% facilities) or minimal (≤25% facilities). Semi-structured interviews were conducted with key informants (policy-makers, implementers, researchers) to identify factors influencing implementation; data were analysed using the Framework Method of thematic analysis.ResultsMost policies were widely implemented in both HDSS (free testing, free antiretroviral treatment (ART), WHO first-line regimen as standard, Option B+). Both had notable implementation gaps for policies relating to retention on treatment (availability of nutritional supplements, support groups or isoniazid preventive therapy). Rakai implemented more policies relating to provision of antiretroviral treatment than Kyamulibwa and performed better on quality of care indicators, such as frequency of stock-outs. Factors facilitating implementation were donor investment and support, strong scientific evidence, low policy complexity, phased implementation and effective planning. Limited human resources, infrastructure and health management information systems w
Silhol R, Gregson S, Nyamukapa C, et al., 2017, Empirical validation of the UNAIDS Spectrum model for subnational HIV estimates: case-study of children and adults in Manicaland, Zimbabwe, AIDS, Vol: 31, Pages: S41-S50, ISSN: 0269-9370
Background: More cost-effective HIV control may be achieved by targeting geographical areas with high infection rates. The AIDS Impact model of Spectrum – used routinely to produce national HIV estimates – could provide the required subnational estimates but is rarely validated with empirical data, even at a national level.Design: The validity of the Spectrum model estimates were compared to empirical estimates.Methods: Antenatal surveillance and population survey data from a population HIV cohort study in Manicaland, east Zimbabwe, were input into Spectrum 5.441 to create a simulation representative of the cohort population. Model and empirical estimates were compared for key demographic and epidemiological outcomes. Alternative scenarios for data availability were examined and sensitivity analyses were conducted for model assumptions considered important for subnational estimates.Results: Spectrum estimates generally agreed with observed data but HIV incidence estimates were higher than empirical estimates while estimates of early age all-cause adult mortality were lower. Child HIV prevalence estimates matched well with the survey prevalence among children. Estimated paternal orphanhood was lower than empirical estimates. Including observations from earlier in the epidemic did not improve the HIV incidence model fit. Migration had little effect on observed discrepancies - possibly because the model ignores differences in HIV prevalence between migrants and residents.Conclusions: The Spectrum model, using subnational surveillance and population data, provided reasonable subnational estimates although some discrepancies were noted. Differences in HIV prevalence between migrants and residents may need to be captured in the model if applied to subnational epidemics.
Wilson KC, Mhangara M, Dzangare J, et al., 2017, Does nonlocal women's attendance at antenatal clinics distort HIV prevalence surveillance estimates in pregnant women in Zimbabwe?, AIDS, Vol: 31, Pages: S95-S102, ISSN: 0269-9370
Objective: The objective was to assess whether HIV prevalence measured among women attending antenatal clinics (ANCs) are representative of prevalence in the local area, or whether estimates may be biased by some women's choice to attend ANCs away from their residential location. We tested the hypothesis that HIV prevalence in towns and periurban areas is underestimated in ANC sentinel surveillance data in Zimbabwe.Methods: National unlinked anonymous HIV surveillance was conducted at 19 ANCs in Zimbabwe in 2000, 2001, 2002, 2004, 2006, 2009, and 2012. This data was used to compare HIV prevalence and nonlocal attendance levels at ANCs at city, town, periurban, and rural clinics in aggregate and also for individual ANCs.Results: In 2000, HIV prevalence at town ANCs (36.6%, 95% CI 34.4–38.9%) slightly underestimated prevalence among urban women attending these clinics (40.7%, 95% CI 37.6–43.9%). However, there was no distortion in HIV prevalence at either the aggregate clinic location or at individual clinics in more recent surveillance rounds. HIV prevalence was consistently higher in towns and periurban areas than in rural areas. Nonlocal attendance was high at town (26–39%) and periurban (53–95%) ANCs but low at city clinics (<10%). However, rural women attending ANCs in towns and periurban areas had higher HIV prevalence than rural women attending rural clinics, and were younger, more likely to be single, and less likely to be housewives.Conclusions: : In Zimbabwe, HIV prevalence among ANC attendees provides reliable estimates of HIV prevalence in pregnant women in the local area.
Sheng B, Marsh K, Slavkovic AB, et al., 2017, Statistical models for incorporating data from routine HIV testing of pregnant women at antenatal clinics into HIV/AIDS epidemic estimates, AIDS, Vol: 31, Pages: S87-S94, ISSN: 0269-9370
Objective: HIV prevalence data collected from routine HIV testing of pregnant women at antenatal clinics (ANC-RT) are potentially available from all facilities that offer testing services to pregnant women and can be used to improve estimates of national and subnational HIV prevalence trends. We develop methods to incorporate these new data source into the Joint United Nations Programme on AIDS Estimation and Projection Package in Spectrum 2017.Methods: We develop a new statistical model for incorporating ANC-RT HIV prevalence data, aggregated either to the health facility level (site-level) or regionally (census-level), to estimate HIV prevalence alongside existing sources of HIV prevalence data from ANC unlinked anonymous testing (ANC-UAT) and household-based national population surveys. Synthetic data are generated to understand how the availability of ANC-RT data affects the accuracy of various parameter estimates.Results: We estimate HIV prevalence and additional parameters using both ANC-RT and other existing data. Fitting HIV prevalence using synthetic data generally gives precise estimates of the underlying trend and other parameters. More years of ANC-RT data should improve prevalence estimates. More ANC-RT sites and continuation with existing ANC-UAT sites may improve the estimate of calibration between ANC-UAT and ANC-RT sites.Conclusion: We have proposed methods to incorporate ANC-RT data into Spectrum to obtain more precise estimates of prevalence and other measures of the epidemic. Many assumptions about the accuracy, consistency, and representativeness of ANC-RT prevalence underlie the use of these data for monitoring HIV epidemic trends and should be tested as more data become available from national ANC-RT programs.
Masquelier B, Eaton JW, Gerland P, et al., 2017, Age patterns and sex ratios of adult mortality in countries with high HIV prevalence, AIDS, Vol: 31, Pages: S77-S85, ISSN: 0269-9370
Objective: To compare the 2016 United Nations Programme on HIV/AIDS (UNAIDS) modelled estimates of adult mortality in sub-Saharan Africa to empirical estimates.Design: Age-specific mortality rates were obtained from nationally representative sibling survival data, recent household deaths and vital registration, and directly compared with UNAIDS estimates. Orphanhood prevalence derived from UNAIDS mortality estimates was compared with survey and census reports on the survival of children's parents.Methods: Age-specific mortality rates for adults aged 15–59 years were calculated from Demographic and Health Surveys and deaths reported in censuses or vital registration, adjusted for underreporting, whenever possible. Proportions of orphans were extracted from censuses and surveys for children aged 5–9 years.Results: UNAIDS estimates were significantly higher than sibling mortality estimates, except among men in countries with very high HIV prevalence. There was a better agreement between rates based on household deaths or vital registration and model outputs. Sex ratios (M/F) of adult mortality were lower in UNAIDS estimates. The modelled orphan prevalence was significantly higher than in surveys and censuses, again with the exception of paternal orphans in countries with very high HIV prevalence. Ratios of paternal-to-maternal orphans were lower in the UNAIDS model than surveys and censuses. Among women, increases in mortality due to AIDS were more concentrated in the age range 25–50 years in model outputs, as compared with empirical estimates.Conclusion: Discrepancies in levels, sex ratios and age patterns of adult mortality between empirical and UNAIDS estimates call for additional data quality assessments and improvements in estimation methods.
Eaton JW, Bao L, 2017, Accounting for nonsampling error in estimates of HIV epidemic trends from antenatal clinic sentinel surveillance, AIDS, Vol: 31, Pages: S61-S68, ISSN: 0269-9370
Objectives: The aim of the study was to propose and demonstrate an approach to allowadditional nonsampling uncertainty about HIV prevalence measured at antenatal clinicsentinel surveillance (ANC-SS) in model-based inferences about trends in HIV incidenceand prevalence.Design: Mathematical model fitted to surveillance data with Bayesian inference.Methods: We introduce a variance inflation parameter s2in fl that accounts for theuncertainty of nonsampling errors in ANC-SS prevalence. It is additive to the samplingerror variance. Three approaches are tested for estimating s2in fl using ANC-SS andhousehold survey data from 40 subnational regions in nine countries in sub-Saharan, asdefined in UNAIDS 2016 estimates. Methods were compared using in-sample fit andout-of-sample prediction of ANC-SS data, fit to household survey prevalence data, andthe computational implications.Results: Introducing the additional variance parameter s2in fl increased the error variancearound ANC-SS prevalence observations by a median of 2.7 times (interquartilerange 1.9–3.8). Using only sampling error in ANC-SS prevalence (s2in fl ¼ 0), coverageof 95% prediction intervals was 69% in out-of-sample prediction tests. This increased to90% after introducing the additional variance parameter s2in fl. The revised probabilisticmodel improved model fit to household survey prevalence and increased epidemicuncertainty intervals most during the early epidemic period before 2005. Estimatings2in fl did not increase the computational cost of model fitting.Conclusions: We recommend estimating nonsampling error in ANC-SS as anadditional parameter in Bayesian inference using the Estimation and Projection Packagemodel. This approach may prove useful for incorporating other data sources such asroutine prevalence from Prevention of mother-to-child transmission testing into futureepidemic estimates.
Reniers G, Blom S, Calvert C, et al., 2016, Trends in the burden of HIV mortality after roll-out of antiretroviral therapy in KwaZulu-Natal, South Africa: an observational community cohort study, Lancet HIV, Vol: 4, Pages: e113-e121, ISSN: 2405-4704
BACKGROUND: Antiretroviral therapy (ART) substantially decreases morbidity and mortality in people living with HIV. In this study, we describe population-level trends in the adult life expectancy and trends in the residual burden of HIV mortality after the roll-out of a public sector ART programme in KwaZulu-Natal, South Africa, one of the populations with the most severe HIV epidemics in the world. METHODS: Data come from the Africa Centre Demographic Information System (ACDIS), an observational community cohort study in the uMkhanyakude district in northern KwaZulu-Natal, South Africa. We used non-parametric survival analysis methods to estimate gains in the population-wide life expectancy at age 15 years since the introduction of ART, and the shortfall of the population-wide adult life expectancy compared with that of the HIV-negative population (ie, the life expectancy deficit). Life expectancy gains and deficits were further disaggregated by age and cause of death with demographic decomposition methods. FINDINGS: Covering the calendar years 2001 through to 2014, we obtained information on 93 903 adults who jointly contribute 535 42 8 person-years of observation to the analyses and 9992 deaths. Since the roll-out of ART in 2004, adult life expectancy increased by 15·2 years for men (95% CI 12·4-17·8) and 17·2 years for women (14·5-20·2). Reductions in pulmonary tuberculosis and HIV-related mortality account for 79·7% of the total life expectancy gains in men (8·4 adult life-years), and 90·7% in women (12·8 adult life-years). For men, 9·5% is the result of a decline in external injuries. By 2014, the life expectancy deficit had decreased to 1·2 years for men (-2·9 to 5·8) and to 5·3 years for women (2·6-7·8). In 2011-14, pulmonary tuberculosis and HIV were responsible for 84·9% of the life expectancy deficit in men and 80·8% in wome
Negin J, Gregson S, Eaton JW, et al., 2016, Rising levels of HIV infection in older adults in eastern Zimbabwe, PLOS One, Vol: 11, ISSN: 1932-6203
BackgroundWith the scale-up of antiretroviral treatment across Africa, many people are living longer with HIV. Understanding the ageing of the HIV cohort and sexual behaviour among older adults are important for appropriately responding to the changing demographics of people living with HIV.MethodsWe used data from a large population-based open cohort in eastern Zimbabwe to examine HIV prevalence trends and incidence among those aged 45 years and older. Five survey rounds have been completed between 1998 and 2011. Incidence was analysed using midpoint between last negative and first positive HIV test.ResultsAcross the survey rounds, 13,071 individuals were followed for 57,676 person years. While HIV prevalence among people aged 15–44 has fallen across the five rounds, HIV prevalence among those aged 45–54 has increased since the 2006–08 survey round. In the 2009–11 round, HIV prevalence among men aged 45–54 was 23.4% compared to 11.0% among those aged 15–44. HIV positive people aged 45–54 now represent more than 20% of all those living with HIV in Manicaland. Among those aged 45 years and older, there were 85 seroconversions in 11,999 person years for an HIV incidence of 0.708 per 100 person years. Analysis of cohort data and assessment of behavioural risk factors for HIV infection among older people shows significantly lower levels of condom use among older adults and a number of seroconversions past the age of 50.ConclusionsThe cohort of people living with HIV is ageing in Zimbabwe and the behaviour of older adults puts them at risk of HIV infection. Older adults must be included in both HIV prevention and treatment programs.
Marston M, Nakiyingi-Miiro J, Kusemererwa S, et al., 2016, The effects of HIV on fertility by infection duration: evidence from African population cohorts before ART availability: Fertility by duration of HIV infection, AIDS, Vol: 31, Pages: S69-S76, ISSN: 1473-5571
OBJECTIVES: To estimate the relationship between HIV natural history and fertility by duration of infection in East and Southern Africa before the availability of antiretroviral therapy, and assess potential biases in estimates of age-specific sub-fertility when using retrospective birth histories in cross-sectional studies. DESIGN: Pooled analysis of prospective population-based HIV cohort studies in Masaka (Uganda) Kisesa (Tanzania), and Manicaland (Zimbabwe). METHODS: Women aged 15-49 who had ever tested for HIV were included. Analyses were censored at antiretroviral treatment roll out. Fertility rate ratios were calculated to see the relationship of duration of HIV infection on fertility, adjusting for background characteristics. Survivorship and misclassification biases on age-specific subfertility estimates from cross-sectional surveys were estimated by reclassifying person time from the cohort data to simulate cross-sectional surveys and comparing fertility rate ratios to true cohort results. RESULTS: HIV negative and positive women contributed 15,440 births and 86320 person years; and 1,236 births and 11240 thousand person years respectively to the final dataset. Adjusting for age, study site and calendar year, each additional year since HIV sero conversion was associated with a 0.02 (95%CI 0.01-0.03) relative decrease infertility for HIV-positive women. Survivorship and misclassification biases in simulated retrospective birth histories resulted in modest underestimates of sub-fertility by 2-5% for age groups 20-39y. CONCLUSION: Longer duration of infection is associated with greater relative fertility reduction for HIV-positive women. This should be considered when creating estimates for HIV prevalence among pregnant women and PMTCT need over the course of the HIV epidemic and ART scale-up.
Olney JJ, Braitstein P, Eaton JW, et al., 2016, Evaluating strategies to improve HIV care outcomes in Kenya: a modelling study, Lancet HIV, Vol: 3, Pages: e592-e600, ISSN: 2405-4704
BackgroundWith expanded access to antiretroviral therapy (ART) in sub-Saharan Africa, HIV mortality has decreased, yet life-years are still lost to AIDS. Strengthening of treatment programmes is a priority. We examined the state of an HIV care programme in Kenya and assessed interventions to improve the impact of ART programmes on population health.MethodsWe created an individual-based mathematical model to describe the HIV epidemic and the experiences of care among adults infected with HIV in Kenya. We calibrated the model to a longitudinal dataset from the Academic Model Providing Access To Healthcare (known as AMPATH) programme describing the routes into care, losses from care, and clinical outcomes. We simulated the cost and effect of interventions at different stages of HIV care, including improvements to diagnosis, linkage to care, retention and adherence of ART, immediate ART eligibility, and a universal test-and-treat strategy.FindingsWe estimate that, of people dying from AIDS between 2010 and 2030, most will have initiated treatment (61%), but many will never have been diagnosed (25%) or will have been diagnosed but never started ART (14%). Many interventions targeting a single stage of the health-care cascade were likely to be cost-effective, but any individual intervention averted only a small percentage of deaths because the effect is attenuated by other weaknesses in care. However, a combination of five interventions (including improved linkage, point-of-care CD4 testing, voluntary counselling and testing with point-of-care CD4, and outreach to improve retention in pre-ART care and on-ART) would have a much larger impact, averting 1·10 million disability-adjusted life-years (DALYs) and 25% of expected new infections and would probably be cost-effective (US$571 per DALY averted). This strategy would improve health more efficiently than a universal test-and-treat intervention if there were no accompanying improvements to care ($1760 per DALY avert
Houben RM, Menzies NA, Sumner T, et al., 2016, Feasibility of achieving the 2025 WHO global tuberculosis targets in South Africa, China, and India: a combined analysis of 11 mathematical models, Lancet Global Health, Vol: 4, Pages: e806-e815, ISSN: 2214-109X
BACKGROUND: The post-2015 End TB Strategy proposes targets of 50% reduction in tuberculosis incidence and 75% reduction in mortality from tuberculosis by 2025. We aimed to assess whether these targets are feasible in three high-burden countries with contrasting epidemiology and previous programmatic achievements. METHODS: 11 independently developed mathematical models of tuberculosis transmission projected the epidemiological impact of currently available tuberculosis interventions for prevention, diagnosis, and treatment in China, India, and South Africa. Models were calibrated with data on tuberculosis incidence and mortality in 2012. Representatives from national tuberculosis programmes and the advocacy community provided distinct country-specific intervention scenarios, which included screening for symptoms, active case finding, and preventive therapy. FINDINGS: Aggressive scale-up of any single intervention scenario could not achieve the post-2015 End TB Strategy targets in any country. However, the models projected that, in the South Africa national tuberculosis programme scenario, a combination of continuous isoniazid preventive therapy for individuals on antiretroviral therapy, expanded facility-based screening for symptoms of tuberculosis at health centres, and improved tuberculosis care could achieve a 55% reduction in incidence (range 31-62%) and a 72% reduction in mortality (range 64-82%) compared with 2015 levels. For India, and particularly for China, full scale-up of all interventions in tuberculosis-programme performance fell short of the 2025 targets, despite preventing a cumulative 3·4 million cases. The advocacy scenarios illustrated the high impact of detecting and treating latent tuberculosis. INTERPRETATION: Major reductions in tuberculosis burden seem possible with current interventions. However, additional interventions, adapted to country-specific tuberculosis epidemiology and health systems, are needed to reach the post-2015 End TB S
Menzies NA, Gomez GB, Bozzani F, et al., 2016, Cost-effectiveness and resource implications of aggressive action on tuberculosis in China, India, and South Africa: a combined analysis of nine models, Lancet Global Health, Vol: 4, Pages: e816-e826, ISSN: 2214-109X
BACKGROUND: The post-2015 End TB Strategy sets global targets of reducing tuberculosis incidence by 50% and mortality by 75% by 2025. We aimed to assess resource requirements and cost-effectiveness of strategies to achieve these targets in China, India, and South Africa. METHODS: We examined intervention scenarios developed in consultation with country stakeholders, which scaled up existing interventions to high but feasible coverage by 2025. Nine independent modelling groups collaborated to estimate policy outcomes, and we estimated the cost of each scenario by synthesising service use estimates, empirical cost data, and expert opinion on implementation strategies. We estimated health effects (ie, disability-adjusted life-years averted) and resource implications for 2016-35, including patient-incurred costs. To assess resource requirements and cost-effectiveness, we compared scenarios with a base case representing continued current practice. FINDINGS: Incremental tuberculosis service costs differed by scenario and country, and in some cases they more than doubled existing funding needs. In general, expansion of tuberculosis services substantially reduced patient-incurred costs and, in India and China, produced net cost savings for most interventions under a societal perspective. In all three countries, expansion of access to care produced substantial health gains. Compared with current practice and conventional cost-effectiveness thresholds, most intervention approaches seemed highly cost-effective. INTERPRETATION: Expansion of tuberculosis services seems cost-effective for high-burden countries and could generate substantial health and economic benefits for patients, although substantial new funding would be required. Further work to determine the optimal intervention mix for each country is necessary. FUNDING: Bill & Melinda Gates Foundation.
Pufall E, Eaton JW, Nyamukapa C, et al., 2016, The relationship between parental education and children's schooling in a time of economic turmoil: The case of East Zimbabwe, 2001 to 2011., International Journal of Educational Development, Vol: 51, Pages: 125-134, ISSN: 1873-4871
Using data collected from 1998 to 2011 in a general population cohort study in eastern Zimbabwe, we describe education trends and the relationship between parental education and children's schooling during the Zimbabwean economic collapse of the 2000s. During this period, the previously-rising trend in education stalled, with girls suffering disproportionately; however, female enrolment increased as the economy began to recover. Throughout the period, children with more educated parents continued to have better outcomes such that, at the population level, an underlying increase in the proportion of children with more educated parents may have helped to maintain the upwards education trend.
Chandrasekaran L, Davies B, Eaton J, et al., 2016, Chlamydia diagnosis rate in England in 2012: an ecological study of local authorities, Sexually Transmitted Infections, Vol: 93, Pages: 226-228, ISSN: 1472-3263
Objectives Local authorities (LAs) in England commission chlamydia screening as part of the National Chlamydia Screening Programme. It is recommended that LAs achieve a chlamydia diagnosis rate of ≥2300 cases per 100 000 population aged 15–24. We describe national patterns in attainment of the chlamydia diagnosis rate recommendation and possible implications of using it to measure LA-level performance.Methods We used publicly available data sets from England (2012) to explore the association between LAs attaining the recommended chlamydia diagnosis rate and population size, socioeconomic deprivation, test setting and sex.Results We used data from 1 197 121 recorded chlamydia tests in females and 564 117 in males. The chlamydia diagnosis rate recommendation was achieved by 22% (72/324) of LAs overall (43% female population; 8% male population). LAs in the highest deprivation quintile were more likely to reach the recommendation than those in the least-deprived quintile for both sexes (women: unadjusted prevalence ratio (UPR) 7.43, 95% CI 3.65 to 15.11; men: UPR 7.00, 95% CI 1.66 to 29.58). The proportion of tests performed in genitourinary medicine clinics was negatively associated with attainment of the recommended diagnosis rate (UPR 0.95, 0.93 to 0.97).Conclusions Chlamydia diagnosis rate recommendations that reflect local area deprivation (as a proxy for disease burden) may be more appropriate than a single national target if the aim is to reduce health inequalities nationally. We suggest LAs monitor their chlamydia diagnosis rate, test coverage and test positivity across a range of measures (including setting and sex) and pre/post changes to commissioned services. Critical evaluation of performance against the recommendation should be reflected in local commissioning decisions.
Yeatman S, Eaton JW, Beckles Z, et al., 2016, Impact of ART on the Fertility of HIV-Positive Women in Sub-Saharan Africa, Tropical Medicine & International Health, Vol: 21, Pages: 1071-1085, ISSN: 1365-3156
ObjectiveUnderstanding the fertility of HIV-positive women is critical to estimating HIV epidemic trends from surveillance data and planning resource needs and coverage of prevention-of-mother-to-child transmission services in sub-Saharan Africa. In light of the considerable scale-up in antiretroviral therapy (ART) coverage over the last decade, we conducted a systematic review of the impact of ART on the fertility outcomes of HIV-positive women.MethodsWe searched Medline, Embase, Popline, PubMed and African Index Medicus. Studies were included if they were conducted in sub-Saharan Africa and provided estimates of fertility outcomes (live births or pregnancies) among women on ART relative to a comparison group.ResultsOf 2070 unique references, 18 published papers met all eligibility criteria. Comparisons fell into four categories: fertility of HIV-positive women relative to HIV-negative women; fertility of HIV-positive women on ART compared to those not yet on ART; fertility differences by duration on ART; and temporal trends in fertility among HIV-positive women. Evidence indicates that fertility increases after approximately the first year on ART, and that while the fertility deficit of HIV-positive women is shrinking, their fertility remains below that of HIV-negative women. These findings, however, were based on limited data mostly during the period 2005-2010 when ART scaled up.ConclusionsExisting data are insufficient to characterize how ART has affected the fertility of HIV-positive women in sub-Saharan Africa. Improving evidence about fertility among women on ART is an urgent priority for planning HIV resource needs and understanding HIV epidemic trends. Alternative data sources such as antenatal clinic data, general population cohorts and population-based surveys can be harnessed to understand the issue.
Stover J, Bollinger L, Izazola JA, et al., 2016, What is required to end the AIDS epidemic as a public health threat by 2030? The cost and impact of the fast-track approach, PLoS One, Vol: 11, ISSN: 1932-6203
In 2011 a new Investment Framework was proposed that described how the scale-up of key HIV interventions could dramatically reduce new HIV infections and AIDS-related deaths in low and middle income countries by 2015. This framework included ambitious coverage goals for prevention and treatment services for 2015, resulting in a reduction of new HIV infections by more than half, in line with the goals of the declaration of the UN High Level Meeting in June 2011. However, the approach suggested a leveling in the number of new infections at about 1 million annually-far from the UNAIDS goal of ending AIDS by 2030. In response, UNAIDS has developed the Fast-Track approach that is intended to provide a roadmap to the actions required to achieve this goal. The Fast-Track approach is predicated on a rapid scale-up of focused, effective prevention and treatment services over the next 5 years and then maintaining a high level of programme implementation until 2030. Fast-Track aims to reduce new infections and AIDS-related deaths by 90% from 2010 to 2030 and proposes a set of biomedical, behavioral and enabling intervention targets for 2020 and 2030 to achieve that goal, including the rapid scale-up initiative for antiretroviral treatment known as 90-90-90. Compared to a counterfactual scenario of constant coverage for all services at early-2015 levels, the Fast-Track approach would avert 18 million HIV infections and 11 million deaths from 2016 to 2030 globally. This paper describes the analysis that produced these targets and the estimated resources needed to achieve them in low- and middle-income countries. It indicates that it is possible to achieve these goals with a significant push to achieve rapid scale-up of key interventions between now and 2020. The annual resources required from all sources would rise to US$7.4Bn in low-income countries, US$8.2Bn in lower middle-income countries and US$10.5Bn in upper-middle-income-countries by 2020 before declining approximately 9
Reniers G, Wamukoya M, Urassa M, et al., 2016, Data resource profile: network for analysing longitudinal population-based HIV/AIDS data on Africa (ALPHA Network), International Journal of Epidemiology, Vol: 45, Pages: 83-93, ISSN: 1464-3685
The Network for Analysing Longitudinal Population-based HIV/AIDS data on Africa (ALPHA Network, http://alpha.lshtm.ac.uk/) brings together ten population-based HIV surveillance sites in eastern and southern Africa, and is coordinated by the London School of Hygiene and TropicalMedicine (LSHTM). It was established in 2005 and aims to (i) broaden the evidence base on HIV epidemiology for informing policy, (ii) strengthen the analytical capacity for HIV research, and (iii) foster collaboration between network members. All study sites, some starting in the late 1980s andearly 1990s, conduct demographic surveillance in populations that range from approximately 20 to 220 thousand individuals. In addition, they conduct population-based surveys with HIV testing, and verbal autopsy interviews with relatives of deceased residents. ALPHA Network datasets have beenused for studying HIV incidence, sexual behaviour and the effects of HIV on mortality, fertility, and household composition. One of the network’s substantive focus areas is the monitoring of AIDS mortality and HIV services coverage in the era of antiretroviral therapy. Service use data areretrospectively recorded in interviews and supplemented by information from record linkage with medical facilities in the surveillance areas. Data access is at the discretion of each of the participating sites, but can be coordinated by the network.
Gregson S, Fenton R, Nyamukapa C, et al., 2016, Wealth Differentials in the Impact of Conditional and Unconditional Cash Transfers on Education: Findings from a Community-Randomised Controlled Trial in Zimbabwe, Psychology, Health & Medicine, Vol: 21, Pages: 909-917, ISSN: 1354-8506
We investigated (1) how household wealth affected the relationshipbetween conditional cash transfers (CCT) and unconditional cashtransfers (UCT) and school attendance, (2) whether CCT and UCTaffected educational outcomes (repeating a year of school), (3) ifbaseline school attendance and transfer conditions affected howmuch of the transfers participants spent on education and (4) if CCTor UCT reduced child labour in recipient households. Data wereanalysed from a cluster-randomized controlled trial of CCT and UCTin 4043 households from 2009 to 2010. Recipient households received$18 dollars per month plus $4 per child. CCT were conditioned onabove 80% school attendance, a full vaccination record and a birthcertificate. In the poorest quintile, the odds ratio of above 80% schoolattendance at follow-up for those with below 80% school attendanceat baseline was 1.06 (p = .67) for UCT vs. CCT. UCT recipients reportedspending slightly more (46.1% (45.4–46.7)) of the transfer on schoolexpenses than did CCT recipients (44.8% (44.1–45.5)). Amongstthose with baseline school attendance of below 80%, there was nostatistically significant difference between CCT and UCT participantsin the proportion of the transfer spent on school expenses (p = .63).Amongst those with above 80% baseline school attendance, CCTparticipants spent 3.5% less (p = .001) on school expenses than UCTparticipants. UCT participants were no less likely than those in thecontrol group to repeat a grade of school. CCT participants had .69(.60–.79) lower odds vs. control of repeating the previous schoolgrade. Children in CCT recipient households spent an average of .31fewer hours in paid work than those in the control group (p < .001)and children in the UCT arm spent an average of .15 fewer hours inpaid work each week than those in the control arm (p = .06).
Phillips A, Shroufi A, Vojnov L, et al., 2015, Sustainable HIV treatment in Africa through viral-load-informed differentiated care, Nature, Vol: 528, Pages: S68-S76, ISSN: 1476-4687
Eaton JW, Bacaer N, Bershteyn A, et al., 2015, Assessment of epidemic projections using recent HIV survey data in South Africa: a validation analysis of ten mathematical models of HIV epidemiology in the antiretroviral therapy era, Lancet Global Health, Vol: 3, Pages: e598-e608, ISSN: 2214-109X
BackgroundMathematical models are widely used to simulate the effects of interventions to control HIV and to project future epidemiological trends and resource needs. We aimed to validate past model projections against data from a large household survey done in South Africa in 2012.MethodsWe compared ten model projections of HIV prevalence, HIV incidence, and antiretroviral therapy (ART) coverage for South Africa with estimates from national household survey data from 2012. Model projections for 2012 were made before the publication of the 2012 household survey. We compared adult (age 15–49 years) HIV prevalence in 2012, the change in prevalence between 2008 and 2012, and prevalence, incidence, and ART coverage by sex and by age groups between model projections and the 2012 household survey.FindingsAll models projected lower prevalence estimates for 2012 than the survey estimate (18·8%), with eight models' central projections being below the survey 95% CI (17·5–20·3). Eight models projected that HIV prevalence would remain unchanged (n=5) or decline (n=3) between 2008 and 2012, whereas prevalence estimates from the household surveys increased from 16·9% in 2008 to 18·8% in 2012 (difference 1·9, 95% CI −0·1 to 3·9). Model projections accurately predicted the 1·6 percentage point prevalence decline (95% CI −0·3 to 3·5) in young adults aged 15–24 years, and the 2·2 percentage point (0·5 to 3·9) increase in those aged 50 years and older. Models accurately represented the number of adults on ART in 2012; six of ten models were within the survey 95% CI of 1·54–2·12 million. However, the differential ART coverage between women and men was not fully captured; all model projections of the sex ratio of women to men on ART were lower than the survey estimate of 2·22 (95% CI 1·73–2·71).InterpretationProjec
Crea TM, Reynolds AD, Sinha A, et al., 2015, Effects of cash transfers on Children's health and social protection in Sub-Saharan Africa: differences in outcomes based on orphan status and household assets, BMC Public Health, Vol: 15, ISSN: 1471-2458
BackgroundUnconditional and conditional cash transfer programmes (UCT and CCT) show potential to improve the well-being of orphans and other children made vulnerable by HIV/AIDS (OVC). We address the gap in current understanding about the extent to which household-based cash transfers differentially impact individual children’s outcomes, according to risk or protective factors such as orphan status and household assets.MethodsData were obtained from a cluster-randomised controlled trial in eastern Zimbabwe, with random assignment to three study arms – UCT, CCT or control. The sample included 5,331 children ages 6-17 from 1,697 households. Generalized linear mixed models were specified to predict OVC health vulnerability (child chronic illness and disability) and social protection (birth registration and 90% school attendance). Models included child-level risk factors (age, orphan status); household risk factors (adults with chronic illnesses and disabilities, greater household size); and household protective factors (including asset-holding). Interactions were systematically tested.ResultsOrphan status was associated with decreased likelihood for birth registration, and paternal orphans and children for whom both parents’ survival status was unknown were less likely to attend school. In the UCT arm, paternal orphans fared better in likelihood of birth registration compared with non-paternal orphans. Effects of study arms on outcomes were not moderated by any other risk or protective factors. High household asset-holding was associated with decreased likelihood of child’s chronic illness and increased birth registration and school attendance, but household assets did not moderate the effects of cash transfers on risk or protective factors.ConclusionOrphaned children are at higher risk for poor social protection outcomes even when cared for in family-based settings. UCT and CCT each produced direct effects on children’s social protection
McGrath N, Eaton JW, Newell M-L, et al., 2015, Migration, sexual behaviour, and HIV risk: a general population cohort in rural South Africa, The Lancet HIV, Vol: 2, Pages: e252-e259, ISSN: 2352-3018
BackgroundIncreased sexual risk behaviour and HIV prevalence have been reported in migrants compared with non-migrants in sub-Saharan Africa. We investigated the association of residential and migration patterns with sexual HIV risk behaviours and HIV prevalence in an open, general population cohort in rural KwaZulu-Natal, South Africa.MethodsIn a mainly rural demographic surveillance area in northern KwaZulu-Natal, South Africa, we collected longitudinal demographic, migration, sexual behaviour, and HIV status data through household surveillance twice per year and individual surveillance once per year. All resident household members and a sample of non-resident household members (stratified by sex and migration patterns) were eligible for participation. Participants reported sexual risk behaviours, including data for multiple, concurrent, and casual sexual partners and condom use, and gave a dried blood spot sample via fingerprick for HIV testing. We investigated population-level differences in sexual HIV risk behaviours and HIV prevalence with respect to migration indicators using logistic regression models.FindingsBetween Jan 1, 2005, and Dec 31, 2011, the total eligible population at each surveillance round ranged between 21 129 and 22 726 women (aged 17–49 years) and between 20 399 and 22 100 men (aged 17–54 years). The number of eligible residents in any round ranged from 24 395 to 26 664 and the number of eligible non-residents ranged from 17 002 to 18 891 between rounds. The stratified sample of non-residents included between 2350 and 3366 individuals each year. Sexual risk behaviours were significantly more common in non-residents than in residents for both men and women. Estimated differences in sexual risk behaviours, but not HIV prevalence, varied between the migration indicators: recent migration, mobility, and migration type. HIV prevalence was significantly increased in current residents with a recent history of migration compared with oth
Eaton JW, Takavarasha FR, Schumacher CM, et al., 2014, Trends in Concurrency, Polygyny, and Multiple Sex Partnerships During a Decade of Declining HIV Prevalence in Eastern Zimbabwe, JOURNAL OF INFECTIOUS DISEASES, Vol: 210, Pages: S562-S568, ISSN: 0022-1899
Pufall EL, Nyamukapa C, Eaton JW, et al., 2014, HIV in Children in a General Population Sample in East Zimbabwe: Prevalence, Causes and Effects, PLOS One, Vol: 9, ISSN: 1932-6203
Background: There are an estimated half-million children living with HIV in sub-Saharan Africa. The predominant source ofinfection is presumed to be perinatal mother-to-child transmission, but general population data about paediatric HIV aresparse. We characterise the epidemiology of HIV in children in sub-Saharan Africa by describing the prevalence, possiblesource of infection, and effects of paediatric HIV in a southern African population.Methods: From 2009 to 2011, we conducted a household-based survey of 3389 children (aged 2–14 years) in Manicaland,eastern Zimbabwe (response rate: 73.5%). Data about socio-demographic correlates of HIV, risk factors for infection, andeffects on child health were analysed using multi-variable logistic regression. To assess the plausibility of mother-to-childtransmission, child HIV infection was linked to maternal survival and HIV status using data from a 12-year adult HIV cohort.Results: HIV prevalence was (2.2%, 95% CI: 1.6–2.8%) and did not differ significantly by sex, socio-economic status, location,religion, or child age. Infected children were more likely to be underweight (19.6% versus 10.0%, p = 0.03) or stunted (39.1%versus 30.6%, p = 0.04) but did not report poorer physical or psychological ill-health. Where maternal data were available,reported mothers of 61/62 HIV-positive children were deceased or HIV-positive. Risk factors for other sources of infectionwere not associated with child HIV infection, including blood transfusion, vaccinations, caring for a sick relative, and sexualabuse. The observed flat age-pattern of HIV prevalence was consistent with UNAIDS estimates which assumes perinatalmother-to-child transmission, although modelled prevalence was higher than observed prevalence. Only 19/73 HIV-positivechildren (26.0%) were diagnosed, but, of these, 17 were on antiretroviral therapy.Conclusions: Childhood HIV infection likely arises predominantly from mother-to-child transmission and is associated wit
Eaton JW, Hallett TB, 2014, Why the proportion of transmission during early-stage HIV infection does not predict the long-term impact of treatment on HIV incidence, PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, Vol: 111, Pages: 16202-16207, ISSN: 0027-8424
Eaton JW, Rehle TM, Jooste S, et al., 2014, Recent HIV prevalence trends among pregnant women and all women in sub-Saharan Africa: implications for HIV estimates, AIDS, Vol: 28, Pages: S507-S514, ISSN: 0269-9370
Objectives: National population-wide HIV prevalence and incidence trends in sub-Saharan Africa (SSA) are indirectly estimated using HIV prevalence measured among pregnant women attending antenatal clinics (ANC), among other data. We evaluated whether recent HIV prevalence trends among pregnant women are representative of general population trends.Design: Serial population-based household surveys in 13 SSA countries.Methods: We calculated HIV prevalence trends among all women aged 15–49 years and currently pregnant women between surveys conducted from 2003 to 2008 (period 1) and 2009 to 2012 (period 2). Log-binomial regression was used to test for a difference in prevalence trend between the two groups. Prevalence among pregnant women was age-standardized to represent the age distribution of all women.Results: Pooling data for all countries, HIV prevalence declined among pregnant women from 6.5 [95% confidence interval (CI) 5.3–7.9%] to 5.3% (95% CI 4.2–6.6%) between periods 1 and 2, whereas it remained unchanged among all women at 8.4% (95% CI 8.0–8.9%) in period 1 and 8.3% (95% CI 7.9–8.8%) in period 2. Prevalence declined by 18% (95% CI -9–38%) more in pregnant women than nonpregnant women. Estimates were similar in Western, Eastern, and Southern regions of SSA; none were statistically significant (P > 0.05). HIV prevalence decreased significantly among women aged 15–24 years while increasing significantly among women 35–49 years, who represented 29% of women but only 15% of pregnant women. Age-standardization of prevalence in pregnant women did not reconcile the discrepant trends because at older ages prevalence was lower among pregnant women than nonpregnant women.Conclusion: As HIV prevalence in SSA has shifted toward older, less-fertile women, HIV prevalence among pregnant women has declined more rapidly than prevalence in women overall. Interpretation of ANC prevalence data to inform national HIV estimates sh
Brown T, Bao L, Eaton JW, et al., 2014, Improvements in prevalence trend fitting and incidence estimation in EPP 2013, AIDS, Vol: 28, Pages: S415-S425, ISSN: 0269-9370
Objective: Describe modifications to the latest version of the Joint United Nations Programme on AIDS (UNAIDS) Estimation and Projection Package component of Spectrum (EPP 2013) to improve prevalence fitting and incidence trend estimation in national epidemics and global estimates of HIV burden.Methods: Key changes made under the guidance of the UNAIDS Reference Group on Estimates, Modelling and Projections include: availability of a range of incidence calculation models and guidance for selecting a model; a shift to reporting the Bayesian median instead of the maximum likelihood estimate; procedures for comparison and validation against reported HIV and AIDS data; incorporation of national surveys as an integral part of the fitting and calibration procedure, allowing survey trends to inform the fit; improved antenatal clinic calibration procedures in countries without surveys; adjustment of national antiretroviral therapy reports used in the fitting to include only those aged 15–49 years; better estimates of mortality among people who inject drugs; and enhancements to speed fitting.Results: The revised models in EPP 2013 allow closer fits to observed prevalence trend data and reflect improving understanding of HIV epidemics and associated data.
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.