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1.
Nature ; 584(7820): 257-261, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32512579

RESUMO

Following the detection of the new coronavirus1 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its spread outside of China, Europe has experienced large epidemics of coronavirus disease 2019 (COVID-19). In response, many European countries have implemented non-pharmaceutical interventions, such as the closure of schools and national lockdowns. Here we study the effect of major interventions across 11 European countries for the period from the start of the COVID-19 epidemics in February 2020 until 4 May 2020, when lockdowns started to be lifted. Our model calculates backwards from observed deaths to estimate transmission that occurred several weeks previously, allowing for the time lag between infection and death. We use partial pooling of information between countries, with both individual and shared effects on the time-varying reproduction number (Rt). Pooling allows for more information to be used, helps to overcome idiosyncrasies in the data and enables more-timely estimates. Our model relies on fixed estimates of some epidemiological parameters (such as the infection fatality rate), does not include importation or subnational variation and assumes that changes in Rt are an immediate response to interventions rather than gradual changes in behaviour. Amidst the ongoing pandemic, we rely on death data that are incomplete, show systematic biases in reporting and are subject to future consolidation. We estimate that-for all of the countries we consider here-current interventions have been sufficient to drive Rt below 1 (probability Rt < 1.0 is greater than 99%) and achieve control of the epidemic. We estimate that across all 11 countries combined, between 12 and 15 million individuals were infected with SARS-CoV-2 up to 4 May 2020, representing between 3.2% and 4.0% of the population. Our results show that major non-pharmaceutical interventions-and lockdowns in particular-have had a large effect on reducing transmission. Continued intervention should be considered to keep transmission of SARS-CoV-2 under control.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Número Básico de Reprodução , COVID-19 , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/transmissão , Europa (Continente)/epidemiologia , Humanos , Pneumonia Viral/mortalidade , Pneumonia Viral/transmissão
2.
Proc Natl Acad Sci U S A ; 120(2): e2200633120, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36595685

RESUMO

Female sex workers (FSW) are affected by individual, network, and structural risks, making them vulnerable to poor health and well-being. HIV prevention strategies and local community-based programs can rely on estimates of the number of FSW to plan and implement differentiated HIV prevention and treatment services. However, there are limited systematic assessments of the number of FSW in countries across sub-Saharan Africa to facilitate the identification of prevention and treatment gaps. Here we provide estimated population sizes of FSW and the corresponding uncertainties for almost all sub-national areas in sub-Saharan Africa. We first performed a literature review of FSW size estimates and then developed a Bayesian hierarchical model to synthesize these size estimates, resolving competing size estimates in the same area and producing estimates in areas without any data. We estimated that there are 2.5 million (95% uncertainty interval 1.9 to 3.1) FSW aged 15 to 49 in sub-Saharan Africa. This represents a proportion as percent of all women of childbearing age of 1.1% (95% uncertainty interval 0.8 to 1.3%). The analyses further revealed substantial differences between the proportions of FSW among adult females at the sub-national level and studied the relationship between these heterogeneities and many predictors. Ultimately, achieving the vision of no new HIV infections by 2030 necessitates dramatic improvements in our delivery of evidence-based services for sex workers across sub-Saharan Africa.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Profissionais do Sexo , Adulto , Humanos , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Teorema de Bayes , África Subsaariana/epidemiologia
3.
Biostatistics ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38423531

RESUMO

Dynamic models have been successfully used in producing estimates of HIV epidemics at the national level due to their epidemiological nature and their ability to estimate prevalence, incidence, and mortality rates simultaneously. Recently, HIV interventions and policies have required more information at sub-national levels to support local planning, decision-making and resource allocation. Unfortunately, many areas lack sufficient data for deriving stable and reliable results, and this is a critical technical barrier to more stratified estimates. One solution is to borrow information from other areas within the same country. However, directly assuming hierarchical structures within the HIV dynamic models is complicated and computationally time-consuming. In this article, we propose a simple and innovative way to incorporate hierarchical information into the dynamical systems by using auxiliary data. The proposed method efficiently uses information from multiple areas within each country without increasing the computational burden. As a result, the new model improves predictive ability and uncertainty assessment.

4.
Nature ; 570(7760): 189-193, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31092927

RESUMO

HIV/AIDS is a leading cause of disease burden in sub-Saharan Africa. Existing evidence has demonstrated that there is substantial local variation in the prevalence of HIV; however, subnational variation has not been investigated at a high spatial resolution across the continent. Here we explore within-country variation at a 5 × 5-km resolution in sub-Saharan Africa by estimating the prevalence of HIV among adults (aged 15-49 years) and the corresponding number of people living with HIV from 2000 to 2017. Our analysis reveals substantial within-country variation in the prevalence of HIV throughout sub-Saharan Africa and local differences in both the direction and rate of change in HIV prevalence between 2000 and 2017, highlighting the degree to which important local differences are masked when examining trends at the country level. These fine-scale estimates of HIV prevalence across space and time provide an important tool for precisely targeting the interventions that are necessary to bringing HIV infections under control in sub-Saharan Africa.


Assuntos
Mapeamento Geográfico , Infecções por HIV/epidemiologia , Adolescente , Adulto , África Subsaariana/epidemiologia , Feminino , Infecções por HIV/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Saúde Pública/estatística & dados numéricos , Saúde Pública/tendências , Adulto Jovem
5.
J Infect Dis ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630583

RESUMO

BACKGROUND: Observational evidence suggests the 4CMenB meningococcal vaccine may partially protect against gonorrhea, with one dose being two-thirds as protective as two. We examined the cost-effectiveness of vaccinating men-who-have-sex-with-men (MSM) in England, with one- or two-dose primary vaccination. METHODS: Integrated transmission-dynamic health-economic modeling explored the effects of targeting strategy, first- and second-dose uptake levels, and duration of vaccine protection, using observational estimates of vaccine protection. RESULTS: Vaccination with one or two primary doses is always cost-saving, irrespective of uptake, although vaccine sentiment is an important determinant of impact and cost-effectiveness. The most impactful and cost-effective targeting is offering "Vaccination-according-to-Risk" (VaR), to all patients with gonorrhea plus those reporting high numbers of sexual partners. If VaR is not feasible to implement then the more-restrictive strategy of "Vaccination-on-Diagnosis" (VoD) with gonorrhea is cost-effective, but much less impactful. Under conservative assumptions, VaR(2-dose) saves £7.62M(95%CrI:1.15-17.52) and gains 81.41(28.67-164.23) QALYs over 10 years; VoD(2-dose) saves £3.40M(0.48-7.71) and gains 41.26(17.52-78.25) QALYs versus no vaccination. Optimistic versus pessimistic vaccine-sentiment assumptions increase net benefits by ∼30%(VoD) or ∼60%(VaR). CONCLUSIONS: At UK costs, targeted 4CMenB vaccination of MSM gains QALYs and is cost-saving at any uptake level. Promoting uptake maximizes benefits and is an important role for behavioral science.

6.
PLoS Med ; 21(5): e1004385, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38768094

RESUMO

BACKGROUND: Syndromic management is widely used to treat symptomatic sexually transmitted infections in settings without aetiologic diagnostics. However, underlying aetiologies and consequent treatment suitability are uncertain without regular assessment. This systematic review estimated the distribution, trends, and determinants of aetiologies for vaginal discharge, urethral discharge, and genital ulcer in sub-Saharan Africa (SSA). METHODS AND FINDINGS: We searched Embase, MEDLINE, Global Health, Web of Science, and grey literature from inception until December 20, 2023, for observational studies reporting aetiologic diagnoses among symptomatic populations in SSA. We adjusted observations for diagnostic test performance, used generalised linear mixed-effects meta-regressions to generate estimates, and critically appraised studies using an adapted Joanna Briggs Institute checklist. Of 4,418 identified records, 206 reports were included from 190 studies in 32 countries conducted between 1969 and 2022. In 2015, estimated primary aetiologies for vaginal discharge were candidiasis (69.4% [95% confidence interval (CI): 44.3% to 86.6%], n = 50), bacterial vaginosis (50.0% [95% CI: 32.3% to 67.8%], n = 39), chlamydia (16.2% [95% CI: 8.6% to 28.5%], n = 50), and trichomoniasis (12.9% [95% CI: 7.7% to 20.7%], n = 80); for urethral discharge were gonorrhoea (77.1% [95% CI: 68.1% to 84.1%], n = 68) and chlamydia (21.9% [95% CI: 15.4% to 30.3%], n = 48); and for genital ulcer were herpes simplex virus type 2 (HSV-2) (48.3% [95% CI: 32.9% to 64.1%], n = 47) and syphilis (9.3% [95% CI: 6.4% to 13.4%], n = 117). Temporal variation was substantial, particularly for genital ulcer where HSV-2 replaced chancroid as the primary cause. Aetiologic distributions for each symptom were largely the same across regions and population strata, despite HIV status and age being significantly associated with several infection diagnoses. Limitations of the review include the absence of studies in 16 of 48 SSA countries, substantial heterogeneity in study observations, and impeded assessment of this variability due to incomplete or inconsistent reporting across studies. CONCLUSIONS: In our study, syndrome aetiologies in SSA aligned with World Health Organization guidelines without strong evidence of geographic or demographic variation, supporting broad guideline applicability. Temporal changes underscore the importance of regular aetiologic re-assessment for effective syndromic management. PROSPERO NUMBER: CRD42022348045.


Assuntos
Úlcera , Descarga Vaginal , Humanos , África Subsaariana/epidemiologia , Feminino , Descarga Vaginal/epidemiologia , Descarga Vaginal/etiologia , Úlcera/epidemiologia , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/diagnóstico , Vaginose Bacteriana/epidemiologia , Vaginose Bacteriana/diagnóstico , Vaginose Bacteriana/complicações , Infecções por Chlamydia/epidemiologia , Infecções por Chlamydia/complicações , Infecções por Chlamydia/diagnóstico , Doenças Uretrais/epidemiologia , Doenças Uretrais/etiologia , Doenças dos Genitais Femininos/epidemiologia
7.
Sex Transm Dis ; 51(3): 206-213, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38412467

RESUMO

BACKGROUND: In settings without etiologic testing for sexually transmitted infections (STIs), programs rely on STI symptom data to inform priorities. To evaluate whether self-reported STI symptoms in household surveys consistently represent the STI burden, we compared symptomatic infection rates between survey self-reporting and health facility case reporting in Malawi. METHODS: We analyzed self-reported symptoms and treatment seeking in the past year among sexually active adults from 4 Malawi Demographic and Health Surveys between 2000 and 2015. Bayesian mixed-effects models were used to estimate temporal trends, spatial variation, and sociodemographic determinants. Survey reporting was compared with health facility syndromic diagnoses between 2014 and 2021. RESULTS: In surveys, 11.0% (95% confidence interval, 10.7%-11.4%) of adults reported STI or STI-related symptoms in the last year, of whom 54.2% (52.8%-55.7%) sought treatment. In facilities, the mean annual symptomatic case diagnosis rate was 3.3%. Survey-reported treatment in the last year was 3.8% (95% credible interval, 2.3%-6.1%) for genital ulcer, 3.8% (2.0%-6.7%) for vaginal discharge, and 2.6% (1.2%-4.7%) for urethral discharge. Mean annual diagnosis rates at facilities were 0.5% for genital ulcer, 2.2% for vaginal discharge, and 2.0% for urethral discharge. Both data sources indicated a higher burden of symptoms among women, individuals older than 25 years, and those in Southern Malawi. CONCLUSIONS: Survey and facility case reports indicated similar spatial and demographic patterns of STI symptom burden and care seeking, but implied large differences in the magnitude and relative burden of symptoms, particularly genital ulcer, which could affect program priorities. Targeted etiologic surveillance would improve interpretation of these data to enable more comprehensive STI surveillance.


Assuntos
Infecções por HIV , Infecções Sexualmente Transmissíveis , Descarga Vaginal , Adulto , Feminino , Humanos , Úlcera , Teorema de Bayes , Malaui/epidemiologia , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções por HIV/epidemiologia
8.
AIDS Behav ; 28(7): 2444-2453, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38878135

RESUMO

We investigated the association between early sexual debut and HIV infection among adolescents and young adults. Analyzing data from nationally representative Population-Based HIV Impact Assessment (PHIA) surveys in 11 African countries, the research employed a multivariate logistic regression model to assess the relationship between the early sexual debut and new HIV infections in the age group of 10-24 years. The results revealed a significant and robust association, indicating that young individuals who experienced early sexual debut were approximately 2.65 times more likely to contract HIV than those who did not, even after accounting for other variables. These findings align with prior research suggesting that early initiation of sexual activity may increase vulnerability to HIV infection due to factors such as biological susceptibility and risky behaviors like low condom use and multiple sexual partners. The implications of these findings for HIV prevention strategies are substantial, suggesting that interventions aimed at delaying sexual debut could be an effective component in reducing HIV risk for this population. Targeted sex education programs that address the risks of early sexual debut may play a pivotal role in these prevention efforts. By employing a comprehensive approach, there is a possibility to advance efforts towards ending AIDS by 2030.


Assuntos
Infecções por HIV , Assunção de Riscos , Comportamento Sexual , Parceiros Sexuais , Humanos , Adolescente , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Masculino , Feminino , Comportamento Sexual/estatística & dados numéricos , Adulto Jovem , África/epidemiologia , Modelos Logísticos , Fatores de Risco , Criança , Preservativos/estatística & dados numéricos , Fatores Etários , Adulto
9.
J Infect Dis ; 228(9): 1198-1207, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37079374

RESUMO

BACKGROUND: Herpes simplex virus type 2 (HSV-2) is an incurable sexually transmitted infection associated with increased risk of acquiring and transmitting human immunodeficiency virus (HIV). HSV-2 is highly prevalent in sub-Saharan Africa, but population-level estimates of incidence are sparse. METHODS: We measured HSV-2 prevalence from cross-sectional serological data among adults aged 18-49 years in 2 south-central Uganda communities (fishing, inland). We identified risk factors for seropositivity, then inferred age patterns of HSV-2 with a Bayesian catalytic model. RESULTS: HSV-2 prevalence was 53.6% (n = 975/1819; 95% confidence interval, 51.3%-55.9%). Prevalence increased with age, was higher in the fishing community, and among women, reaching 93.6% (95% credible interval, 90.2%-96.6%) by age 49 years. Factors associated with HSV-2 seropositivity included more lifetime sexual partners, HIV positive status, and lower education. HSV-2 incidence peakied at age 18 years for women and 19-20 years for men. HIV prevalence was up to 10-fold higher in HSV-2-positive individuals. CONCLUSIONS: HSV-2 prevalence and incidence were extremely high, with most infections occurring in late adolescence. Interventions against HSV-2, such as future vaccines or therapeutics, must target young populations. Remarkably higher HIV prevalence among HSV-2-positive individuals underscores this population as a priority for HIV prevention.


Assuntos
Infecções por HIV , Soropositividade para HIV , Herpes Genital , Adulto , Masculino , Adolescente , Humanos , Feminino , Pessoa de Meia-Idade , Herpesvirus Humano 2 , Uganda/epidemiologia , Estudos Soroepidemiológicos , Prevalência , Incidência , Estudos Transversais , Teorema de Bayes , Fatores de Risco , Soropositividade para HIV/complicações , Infecções por HIV/epidemiologia , Infecções por HIV/complicações , Comportamento Sexual
10.
Epidemiology ; 34(3): 353-364, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36863062

RESUMO

BACKGROUND: Estimating HIV-1 incidence using biomarker assays in cross-sectional surveys is important for understanding the HIV pandemic. However, the utility of these estimates has been limited by uncertainty about what input parameters to use for false recency rate (FRR) and mean duration of recent infection (MDRI) after applying a recent infection testing algorithm (RITA). METHODS: This article shows how testing and diagnosis reduce both FRR and mean duration of recent infection compared to a treatment-naive population. A new method is proposed for calculating appropriate context-specific estimates of FRR and mean duration of recent infection. The result of this is a new formula for incidence that depends only on reference FRR and mean duration of recent infection parameters derived in an undiagnosed, treatment-naive, nonelite controller, non-AIDS-progressed population. RESULTS: Applying the methodology to eleven cross-sectional surveys in Africa results in good agreement with previous incidence estimates, except in 2 countries with very high reported testing rates. CONCLUSIONS: Incidence estimation equations can be adapted to account for the dynamics of treatment and recent infection testing algorithms. This provides a rigorous mathematical foundation for the application of HIV recency assays in cross-sectional surveys.


Assuntos
Biomarcadores , Infecções por HIV , Biomarcadores/análise , Infecções por HIV/diagnóstico , Infecções por HIV/metabolismo , Infecções por HIV/terapia , Incidência , Algoritmos , Estudos Transversais , Humanos , Masculino , Feminino
11.
PLoS Med ; 19(1): e1003861, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35077459

RESUMO

BACKGROUND: Key populations, including sex workers, are at high risk of HIV acquisition and transmission. Men who pay for sex can contribute to HIV transmission through sexual relationships with both sex workers and their other partners. To characterize the population of men who pay for sex in sub-Saharan Africa (SSA), we analyzed population size, HIV prevalence, and use of HIV prevention and treatment. METHODS AND FINDINGS: We performed random-effects meta-analyses of population-based surveys conducted in SSA from 2000 to 2020 with information on paid sex by men. We extracted population size, lifetime number of sexual partners, condom use, HIV prevalence, HIV testing, antiretroviral (ARV) use, and viral load suppression (VLS) among sexually active men. We pooled by regions and time periods, and assessed time trends using meta-regressions. We included 87 surveys, totaling over 368,000 male respondents (15-54 years old), from 35 countries representing 95% of men in SSA. Eight percent (95% CI 6%-10%; number of surveys [Ns] = 87) of sexually active men reported ever paying for sex. Condom use at last paid sex increased over time and was 68% (95% CI 64%-71%; Ns = 61) in surveys conducted from 2010 onwards. Men who paid for sex had higher HIV prevalence (prevalence ratio [PR] = 1.50; 95% CI 1.31-1.72; Ns = 52) and were more likely to have ever tested for HIV (PR = 1.14; 95% CI 1.06-1.24; Ns = 81) than men who had not paid for sex. Men living with HIV who paid for sex had similar levels of lifetime HIV testing (PR = 0.96; 95% CI 0.88-1.05; Ns = 18), ARV use (PR = 1.01; 95% CI 0.86-1.18; Ns = 8), and VLS (PR = 1.00; 95% CI 0.86-1.17; Ns = 9) as those living with HIV who did not pay for sex. Study limitations include a reliance on self-report of sensitive behaviors and the small number of surveys with information on ARV use and VLS. CONCLUSIONS: Paying for sex is prevalent, and men who ever paid for sex were 50% more likely to be living with HIV compared to other men in these 35 countries. Further prevention efforts are needed for this vulnerable population, including improved access to HIV testing and condom use initiatives. Men who pay for sex should be recognized as a priority population for HIV prevention.


Assuntos
Infecções por HIV , Densidade Demográfica , Sexo , África Subsaariana/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Masculino , Homens , Prevalência
12.
MMWR Morb Mortal Wkly Rep ; 71(9): 329-334, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35239633

RESUMO

Persons infected with HIV are more likely to transmit the virus during the early stages (acute and recent) of infection, when viral load is elevated and opportunities to implement risk reduction are limited because persons are typically unaware of their status (1,2). Identifying recent HIV infections (acquired within the preceding 12 months)* is critical to understanding the factors and geographic areas associated with transmission to strengthen program intervention, including treatment and prevention (2). During June 2019, a novel recent infection surveillance initiative was integrated into routine HIV testing services in Malawi, a landlocked country in southeastern Africa with one of the world's highest prevalences of HIV infection.† The objectives of this initiative were to collect data on new HIV diagnoses, characterize the epidemic, and guide public health response (2). New HIV diagnoses were classified as recent infections based on a testing algorithm that included results from the rapid test for recent infection (RTRI)§ and HIV viral load testing (3,4). Among 9,168 persons aged ≥15 years with a new HIV diagnosis who received testing across 103 facilities during October 2019-March 2020, a total of 304 (3.3%) were classified as having a recent infection. Higher proportions of recent infections were detected among females, persons aged <30 years, and clients at maternal and child health and youth clinics. Using a software application that analyzes clustering in spatially referenced data, transmission hotspots were identified with rates of recent infection that were significantly higher than expected. These near real-time HIV surveillance data highlighted locations across Malawi, allowing HIV program stakeholders to assess program gaps and improve access to HIV testing, prevention, and treatment services. Hotspot investigation information could be used to tailor HIV testing, prevention, and treatment to ultimately interrupt transmission.


Assuntos
Hotspot de Doença , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Teste de HIV/métodos , Vigilância de Evento Sentinela , Análise Espacial , Adulto , Feminino , Humanos , Malaui/epidemiologia , Masculino , Saúde Pública , Software , Adulto Jovem
13.
BMC Public Health ; 22(1): 1120, 2022 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-35659216

RESUMO

BACKGROUND: Debuting sexual intercourse marks exposure to pregnancy or fatherhood and sexually transmitted infections (STIs), including HIV. In sub-Saharan Africa (SSA), sexual debut varies according to cultural, religious, and economic factors, and encouraging delay has been a longstanding component of behavioural HIV prevention strategies. Age at first sex (AFS) is routinely collected in national household surveys, but data are affected by reporting biases, limiting utility to monitor trends and guide sexual health interventions. METHODS: We collated individual-level data from nationally-representative household surveys to analyse timing and national trends in AFS in 42 SSA countries. We used a log-skew-logistic distribution to characterize the time to AFS in a Bayesian spatio-temporal model, providing estimates of the sexual debut rate by sex, age, time, and country. We statistically adjusted for reporting biases by comparing AFS reported by the same birth cohorts in multiple survey rounds, allowing different reporting biases by sex and country. RESULTS: Median AFS in 2015 ranged from 15.8 among Angolan women to 25.3 among men in Niger. AFS was younger for women than men in 37/40 countries. The gap was largest for Sahel region countries and minimal in southern African countries. The distribution of female AFS was asymmetric with half debuting sex in an age range of 3.9 years [IQR 3.4-5.0 across countries]. Median AFS increased slightly between 1985 and 2020, ranging 0.84 years [IQR 0.11-1.55] and 0.79 [IQR -0.23-1.98] for females and males, respectively. The gender gap changed little over time in most countries. Female teens often reported higher AFS compared to when asked in their late twenties while male teens reported lower AFS; both sexes recalled a higher AFS in older ages compared to their thirties. CONCLUSIONS: AFS increased slightly in most SSA countries, but changes were modest relative to large and persistent variation between countries and sexes, indicating relatively entrenched socio-cultural practices around sexual debut. Sexual health, family planning, and HIV/STI prevention services should adapt to local practices rather than focusing interventions to change AFS. These estimates for rates of sexual debut provide data to guide programmatic prioritization and implementation of sexual health services.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Infecções Sexualmente Transmissíveis , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Adolescente , Adulto , África Subsaariana/epidemiologia , Teorema de Bayes , Coorte de Nascimento , Pré-Escolar , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Masculino , Gravidez , Comportamento Sexual , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle
14.
PLoS Med ; 18(5): e1003651, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34029346

RESUMO

Peter Ehrenkranz and co-authors present a cyclical cascade of care for people with HIV infection, aiming to facilitate assessment of outcomes.


Assuntos
Síndrome da Imunodeficiência Adquirida/terapia , Atenção à Saúde/normas , HIV/fisiologia , Objetivos , Humanos , Nações Unidas
15.
Nature ; 528(7580): S68-76, 2015 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-26633768

RESUMO

There are inefficiencies in current approaches to monitoring patients on antiretroviral therapy in sub-Saharan Africa. Patients typically attend clinics every 1 to 3 months for clinical assessment. The clinic costs are comparable with the costs of the drugs themselves and CD4 counts are measured every 6 months, but patients are rarely switched to second-line therapies. To ensure sustainability of treatment programmes, a transition to more cost-effective delivery of antiretroviral therapy is needed. In contrast to the CD4 count, measurement of the level of HIV RNA in plasma (the viral load) provides a direct measure of the current treatment effect. Viral-load-informed differentiated care is a means of tailoring care so that those with suppressed viral load visit the clinic less frequently and attention is focussed on those with unsuppressed viral load to promote adherence and timely switching to a second-line regimen. The most feasible approach to measuring viral load in many countries is to collect dried blood spot samples for testing in regional laboratories; however, there have been concerns over the sensitivity and specificity of this approach to define treatment failure and the delay in returning results to the clinic. We use modelling to synthesize evidence and evaluate the cost-effectiveness of viral-load-informed differentiated care, accounting for limitations of dried blood sample testing. We find that viral-load-informed differentiated care using dried blood sample testing is cost-effective and is a recommended strategy for patient monitoring, although further empirical evidence as the approach is rolled out would be of value. We also explore the potential benefits of point-of-care viral load tests that may become available in the future.


Assuntos
Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Medicina de Precisão/métodos , Carga Viral , Adolescente , Adulto , África , Idoso , Fármacos Anti-HIV/economia , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Análise Custo-Benefício , Infecções por HIV/diagnóstico , Infecções por HIV/economia , Humanos , Pessoa de Meia-Idade , Medicina de Precisão/economia , Carga Viral/efeitos dos fármacos , Adulto Jovem
16.
Demogr Res ; 44: 415-442, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35368427

RESUMO

BACKGROUND: Estimates of under-5 mortality (U5M) for sub-Saharan African populations often rely heavily on full birth histories (FBHs) collected in surveys and model age patterns of mortality calibrated against vital statistics from other populations. Health and Demographic Surveillance Systems (HDSSs) are alternate sources of population-based data in much of sub-Saharan Africa, which are less formally utilized in estimation. OBJECTIVE: In this study we compare the age pattern of U5M in different African data sources (HDSSs, Demographic and Health Surveys (DHS), and Multiple Indicator Cluster Surveys (MICS)), and contrast these with the historical record as summarized in the Human Mortality Database and model age patterns. METHODS: We examined the relative levels of neonatal, postneonatal, infant, and child mortality across data sources. We directly compared estimates for DHS and MICS subnational regions with HDSS, and used linear regression to identify data and contextual attributes that correlated with the disparity between estimates. RESULTS: HDSS and FBH data suggests that African populations have higher levels of child mortality and lower infant mortality than the historic record. This age pattern is most explicit for Western African populations, but also characterizes data for other subregions. The comparison between HDSS and FBH data suggests that FBH estimates of child mortality are biased downward. The comparison is less conclusive for neonatal and infant mortality. CONTRIBUTION: This study questions the practice of using model age patterns derived from largely high-income settings for inferring or correcting U5M estimates for African populations. It also highlights the considerable uncertainty around the consistency of HDSS and FBH estimates of U5M.

17.
BMC Med ; 18(1): 189, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32631314

RESUMO

BACKGROUND: HIV remains the largest cause of disease burden among men and women of reproductive age in sub-Saharan Africa. Voluntary medical male circumcision (VMMC) reduces the risk of female-to-male transmission of HIV by 50-60%. The World Health Organization (WHO) and Joint United Nations Programme on HIV/AIDS (UNAIDS) identified 14 priority countries for VMMC campaigns and set a coverage goal of 80% for men ages 15-49. From 2008 to 2017, over 18 million VMMCs were reported in priority countries. Nonetheless, relatively little is known about local variation in male circumcision (MC) prevalence. METHODS: We analyzed geo-located MC prevalence data from 109 household surveys using a Bayesian geostatistical modeling framework to estimate adult MC prevalence and the number of circumcised and uncircumcised men aged 15-49 in 38 countries in sub-Saharan Africa at a 5 × 5-km resolution and among first administrative level (typically provinces or states) and second administrative level (typically districts or counties) units. RESULTS: We found striking within-country and between-country variation in MC prevalence; most (12 of 14) priority countries had more than a twofold difference between their first administrative level units with the highest and lowest estimated prevalence in 2017. Although estimated national MC prevalence increased in all priority countries with the onset of VMMC campaigns, seven priority countries contained both subnational areas where estimated MC prevalence increased and areas where estimated MC prevalence decreased after the initiation of VMMC campaigns. In 2017, only three priority countries (Ethiopia, Kenya, and Tanzania) were likely to have reached the MC coverage target of 80% at the national level, and no priority country was likely to have reached this goal in all subnational areas. CONCLUSIONS: Despite MC prevalence increases in all priority countries since the onset of VMMC campaigns in 2008, MC prevalence remains below the 80% coverage target in most subnational areas and is highly variable. These mapped results provide an actionable tool for understanding local needs and informing VMMC interventions for maximum impact in the continued effort towards ending the HIV epidemic in sub-Saharan Africa.


Assuntos
Circuncisão Masculina/tendências , Infecções por HIV/prevenção & controle , Adolescente , Adulto , África , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
18.
BMC Public Health ; 20(1): 1599, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33097016

RESUMO

BACKGROUND: Benefits of cash transfers (CTs) for HIV prevention have been demonstrated largely in purposively designed trials, commonly focusing on young women. It is less clear if CT interventions not designed for HIV prevention can have HIV-specific effects, including adverse effects. The cluster-randomised Manicaland Cash Transfer Trial (2010-11) evaluated effects of CTs on children's (2-17 years) development in eastern Zimbabwe. We evaluated whether this CT intervention with no HIV-specific objectives had unintended HIV prevention spillover effects (externalities). METHODS: Data on 2909 individuals (15-54 years) living in trial households were taken from a general-population survey, conducted simultaneously in the same communities as the Manicaland Trial. Average treatment effects (ATEs) of CTs on sexual behaviour (any recent sex, condom use, multiple partners) and secondary outcomes (mental distress, school enrolment, and alcohol/cigarette/drug consumption) were estimated using mixed-effects logistic regressions (random effects for study site and intervention cluster), by sex and age group (15-29; 30-54 years). Outcomes were also evaluated with a larger synthetic comparison group created through propensity score matching. RESULTS: CTs did not affect sexual debut but reduced having any recent sex (past 30 days) among young males (ATE: - 11.7 percentage points [PP] [95% confidence interval: -26.0PP, 2.61PP]) and females (- 5.68PP [- 15.7PP, 4.34PP]), with similar but less uncertain estimates when compared against the synthetic comparison group (males: -9.68PP [- 13.1PP, - 6.30PP]; females: -8.77PP [- 16.3PP, - 1.23PP]). There were no effects among older individuals. Young (but not older) males receiving CTs reported increased multiple partnerships (8.49PP [- 5.40PP, 22.4PP]; synthetic comparison: 10.3PP (1.27PP, 19.2PP). No impact on alcohol, cigarette, or drug consumption was found. There are indications that CTs reduced psychological distress among young people, although impacts were small. CTs increased school enrolment in males (11.5PP [3.05PP, 19.9PP]). Analyses with the synthetic comparison group (but not the original control group) further indicated increased school enrolment among females (5.50PP [1.62PP, 9.37PP]) and condom use among younger and older women receiving CTs (9.38PP [5.90PP, 12.9PP]; 5.95PP [1.46PP, 10.4PP]). CONCLUSIONS: Non-HIV-prevention CT interventions can have HIV prevention outcomes, including reduced sexual activity among young people and increased multiple partnerships among young men. No effects on sexual debut or alcohol, cigarette, or drug consumption were observed. A broad approach is necessary to evaluate CT interventions to capture unintended outcomes, particularly in economic evaluations. TRIAL REGISTRATION: ClinicalTrials.gov , NCT00966849 . Registered August 27, 2009.


Assuntos
Infecções por HIV/economia , Infecções por HIV/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Comportamento Sexual/estatística & dados numéricos , Parceiros Sexuais , Adolescente , Adulto , Análise por Conglomerados , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Sexo Seguro/estatística & dados numéricos , Estudantes/estatística & dados numéricos , Inquéritos e Questionários , Adulto Jovem , Zimbábue/epidemiologia
19.
Popul Stud (Camb) ; 74(1): 93-102, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31117928

RESUMO

There are limited data on the impact of antiretroviral therapy (ART) on population-level adult mortality in sub-Saharan Africa. We analysed data for 2000-14 from the Rakai Community Cohort Study (RCCS) in Uganda, where free ART was scaled up after 2004. Using non-parametric and parametric (Weibull) survival analysis, we estimated trends in average person-years lived between exact ages 15 and 50, per capita life-years lost to HIV, and the mortality hazards of people living with HIV (PLHIV). Between 2000 and 2014, average adult life-years lived before age 50 increased significantly, from 26.4 to 33.5 years for all women and from 28.6 to 33.8 years for all men. As of 2014, life-years lost to HIV had declined significantly, to 1.3 years among women and 0.4 years among men. Following the roll-out of ART, mortality reductions among PLHIV were initially larger in women than men, but this is no longer the case.


Assuntos
Antirretrovirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Mortalidade/tendências , Adolescente , Adulto , Infecções por HIV/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Uganda/epidemiologia , Adulto Jovem
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