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1.
PLoS Med ; 20(4): e1004203, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37083700

RESUMEN

BACKGROUND: The growing population of adolescents and young people (AYP) aged 15 to 24 in sub-Saharan Africa face a high burden of HIV in many settings. Unintended pregnancies among adolescent girls in the region remain high. Nonetheless, the sexual and reproductive health (SRH) service needs of AYP have remained underserved. We conducted a cluster-randomised trial (CRT) to estimate the impact of community-based, peer-led SRH service provision on knowledge of HIV status and other SRH outcomes, including met need for contraceptives. METHODS AND FINDINGS: Yathu Yathu was a cluster-randomised trial (CRT) conducted from 2019 to 2021 in 2 urban communities in Lusaka, Zambia. The communities were divided into 20 zones (approximately 2,350 AYP/zone) that were randomly allocated to the Yathu Yathu intervention or control arm. In each intervention zone, a community-based hub, staffed by peer support workers, was established to provide SRH services. In 2019, a census was conducted in all zones; all consenting AYP aged 15 to 24 were given a Yathu Yathu card, which allowed them to accrue points for accessing SRH services at the hub and health facility (intervention arm) or the health facility only (control arm). Points could be exchanged for rewards, thus acting as an incentive to use SRH services in both arms. We conducted a cross-sectional survey in 2021 to estimate the impact of Yathu Yathu on the primary outcome: knowledge of HIV status (self-reporting living with HIV or HIV testing in the last 12 months) and secondary outcomes, including use of pre-exposure prophylaxis (PrEP) in the last 12 months, current use of antiretroviral therapy (ART), and met need for contraceptive services. The sampling was stratified on sex and age group, and we analysed data at cluster-level using a two-stage process recommended for CRTs with <15 clusters/arm. A total of 1,989 AYP consented to participate in the survey (50% male); consent was similar across arms (63% consent/arm). Across zones, knowledge of HIV status ranged from 63.6% to 81.2% in intervention zones and 35.4% to 63.0% in control zones. Adjusting for age, sex, and community, knowledge of HIV status was higher in the intervention arm compared to control (73.3% versus 48.4%, respectively, adjusted prevalence ratio (PR) 1.53 95% CI 1.36, 1.72; p < 0.001). By age and sex, results were similar. There was no evidence for impact on any secondary outcomes, including current use of ART and met need for contraceptives. There were no adverse events reported in either arm. A key limitation of our trial is that approximately 35% of the AYP randomly selected for participation in the endline survey could not be reached. CONCLUSIONS: Delivering community-based, peer-led SRH services increased knowledge of HIV status among AYP, both males and females, compared with the control arm. Scaling up the highly effective Yathu Yathu strategy has the potential to make a substantial contribution to increasing access to HIV prevention and care services for young people. However, additional implementation research is needed to understand how to improve uptake of broader SRH services, beyond uptake of HIV testing. TRIAL REGISTRATION: ISRCTN75609016, clinicaltrials.gov number NCT04060420.


Asunto(s)
Infecciones por VIH , Servicios de Salud Reproductiva , Embarazo , Femenino , Humanos , Masculino , Adolescente , Zambia/epidemiología , Estudios Transversales , Servicios de Salud Comunitaria/métodos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Prueba de VIH , Anticonceptivos
2.
BMC Infect Dis ; 23(1): 518, 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37553658

RESUMEN

BACKGROUND: Chest X-rays (CXRs) have traditionally been used to aid the diagnosis of TB-suggestive abnormalities. Using Computer-Aided Detection (CAD) algorithms, TB risk is quantified to assist with diagnostics. However, CXRs capture all other structural abnormalities. Identification of non-TB abnormalities in individuals with CXRs that have high CAD scores but don't have bacteriologically confirmed TB is unknown. This presents a missed opportunity of extending novel CAD systems' potential to simultaneously provide information on other non-TB abnormalities alongside TB. This study aimed to characterize and estimate the prevalence of non-TB abnormalities on digital CXRs with high CAD4TB scores from a TB prevalence survey in Zambia and South Africa. METHODOLOGY: This was a cross-sectional analysis of clinical data of participants from the TREATS TB prevalence survey conducted in 21 communities in Zambia and South Africa. The study included individuals aged ≥ 15 years who had high CAD4TB scores (score ≥ 70), but had no bacteriologically confirmed TB in any of the samples submitted, were not on TB treatment, and had no history of TB. Two consultant radiologists reviewed the images for non-TB abnormalities. RESULTS: Of the 525 CXRs reviewed, 46.7% (245/525) images were reported to have non-TB abnormalities. About 11.43% (28/245) images had multiple non-TB abnormalities, while 88.67% (217/245) had a single non-TB abnormality. The readers had a fair inter-rater agreement (r = 0.40). Based on anatomical location, non-TB abnormalities in the lung parenchyma (19%) were the most prevalent, followed by Pleura (15.4%), then heart & great vessels (6.1%) abnormalities. Pleural effusion/thickening/calcification (8.8%) and cardiomegaly (5%) were the most prevalent non-TB abnormalities. Prevalence of (2.7%) for pneumonia not typical of pulmonary TB and (2.1%) mass/nodules (benign/ malignant) were also reported. CONCLUSION: A wide range of non-TB abnormalities can be identified on digital CXRs among individuals with high CAD4TB scores but don't have bacteriologically confirmed TB. Adaptation of AI systems like CAD4TB as a tool to simultaneously identify other causes of abnormal CXRs alongside TB can be interesting and useful in non-faculty-based screening programs to better link cases to appropriate care.


Asunto(s)
Tuberculosis , Humanos , Zambia/epidemiología , Sudáfrica/epidemiología , Prevalencia , Estudios Transversales , Rayos X , Sensibilidad y Especificidad , Tuberculosis/diagnóstico por imagen , Tuberculosis/epidemiología
3.
BMC Public Health ; 23(1): 1414, 2023 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-37488552

RESUMEN

BACKGROUND: The health impact of the COVID-19 pandemic largely depends on the ability of the healthcare systems to develop effective and adaptable preparedness and mitigation strategies. A collaborative initiative (BRCCH-EDCTP COVID-19 Initiative) was set up between Lesotho and Zambia early on in the pandemic, to jointly conduct a project to investigate creating access to SARS-CoV-2 screening and testing through community-based COVID-19 case-finding. METHODS: Two different community case-finding strategies were deployed. In Lesotho, an approach was implemented whereby a community (village) health worker screened community members at their home or during community gatherings for COVID-19 signs and symptoms. All community members who screened positive were then offered SARS-CoV-2 testing. In Zambia, so-called community hubs, staffed by community health care workers, were set up at different locations in the community for people to walk in and get tested for SARS-CoV-2. Hubs changed location from week-to-week and targeted transmission hotspots. All persons visiting the hubs were offered testing for SARS-CoV-2 irrespective of self-reported signs and symptoms of COVID-19 though information was collected on occurrence of these. Testing in both approaches was done using SARS-CoV-2 rapid antigen tests. RESULTS: Setting up testing in the community setting was feasible in both countries. In Lesotho in the village health worker approach, over a period of 46 weeks, 7221 persons were screened, and 49 (11.4%) SARS-COV-2 cases identified among 428 COVID-19 screen positive participants. In the community hubs among 3150 people tested, 166 (5.3%) SARS-CoV-2 cases were identified in a period of 26 weeks. From the community hubs approach, where all seen were offered COVID-19 testing it was learned that people screening positive for COVID-19 signs and symptoms were more likely to test SARS-COV-2 positive, especially those reporting classic COVID-19 symptoms like loss of sense/smell for a short period of time (1-3 days). CONCLUSIONS: In conclusion, in this project we learned that implementing COVID-19 screening and testing by lay health workers in the community is possible. Characteristics of the population screened, tested, and identified to have SARS-CoV-2 are described to help guide development of future testing strategies.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Prueba de COVID-19 , Estudios Transversales , Lesotho , Pandemias , Zambia , Agentes Comunitarios de Salud
4.
Reprod Health ; 20(1): 92, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37340497

RESUMEN

BACKGROUND: Globally, millions of adolescent girls and young women (AGYW) who menstruate have limited access to appropriate and comfortable products to manage their menstruation. Yathu Yathu was a cluster randomised trial (CRT) that estimated the impact of community-based, peer-led sexual and reproductive health (SRH) services on knowledge of HIV status among adolescents and young people aged 15-24 (AYP). Among the services offered through Yathu Yathu were free disposable pads and menstrual cups. This study aimed to investigate whether the availability of free menstrual products through Yathu Yathu increased AGYW's use of an appropriate menstrual product at their last menstruation and explored the characteristics of AGYW who accessed menstrual products through Yathu Yathu. METHODS: Yathu Yathu was conducted between 2019 and 2021 in 20 zones across two urban communities of Lusaka, Zambia. Zones were randomly allocated to the intervention or standard-of-care arm. In intervention zones, a community-based hub, staffed by peers, was established to provide SRH services. In 2019, a census was conducted in all zones; all consenting AYP aged 15-24 were given a Yathu Yathu Prevention Points Card, which allowed AYP to accrue points for accessing services at the hub and health facility (intervention arm), or the health facility only (control arm). Points could be exchanged for rewards, thus acting as an incentive in both arms. We conducted a cross-sectional survey in 2021 to estimate the impact of Yathu Yathu on the primary outcome (knowledge of HIV status) and secondary outcomes. Sampling was stratified by sex and age group; we analysed data from AGYW only to estimate the impact of Yathu Yathu on use of an appropriate menstrual product (disposable or reusable pad, cup, tampon) at last menstruation. We analysed data at zone-level using a two-stage process recommended for CRTs with < 15 clusters/arm. RESULTS: Among 985 AGYW participating in the survey who had experienced menarche, the most commonly used products were disposable pads (88.8%; n = 875/985). At their last menstruation, 93.3% (n = 459/492) of AGYW in the intervention arm used an appropriate menstrual product compared to 85.7% (n = 420/490) in the control arm (adjPR = 1.09 95%CI 1.02, 1.17; p = 0.02). There was no evidence for interaction by age (p = 0.20), but use of appropriate products was higher among adolescents in the intervention arm relative to control (95.5% vs 84.5%, adjPR = 1.14 95%CI 1.04, 1.25; p = 0.006) with no evidence for a difference among young women (91.1% vs 87.0%, adjPR = 1.06 95%CI 0.96, 1.16, p = 0.22). CONCLUSIONS: Delivering community-based peer-led SRH services increased the use of appropriate menstrual products among adolescent girls aged 15-19 at the start of the Yathu Yathu study. With less economic independence, the free provision of appropriate menstrual products is critical for adolescent girls to access materials that allow them to effectively manage their menstruation.


Asunto(s)
Infecciones por VIH , Servicios de Salud Reproductiva , Adolescente , Humanos , Femenino , Productos para la Higiene Menstrual , Estudios Transversales , Zambia , Servicios de Salud Comunitaria , Menstruación , Conocimientos, Actitudes y Práctica en Salud
5.
N Engl J Med ; 381(3): 207-218, 2019 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-31314965

RESUMEN

BACKGROUND: A universal testing and treatment strategy is a potential approach to reduce the incidence of human immunodeficiency virus (HIV) infection, yet previous trial results are inconsistent. METHODS: In the HPTN 071 (PopART) community-randomized trial conducted from 2013 through 2018, we randomly assigned 21 communities in Zambia and South Africa (total population, approximately 1 million) to group A (combination prevention intervention with universal antiretroviral therapy [ART]), group B (the prevention intervention with ART provided according to local guidelines [universal since 2016]), or group C (standard care). The prevention intervention included home-based HIV testing delivered by community workers, who also supported linkage to HIV care and ART adherence. The primary outcome, HIV incidence between months 12 and 36, was measured in a population cohort of approximately 2000 randomly sampled adults (18 to 44 years of age) per community. Viral suppression (<400 copies of HIV RNA per milliliter) was assessed in all HIV-positive participants at 24 months. RESULTS: The population cohort included 48,301 participants. Baseline HIV prevalence was 21% or 22% in each group. Between months 12 and 36, a total of 553 new HIV infections were observed during 39,702 person-years (1.4 per 100 person-years; women, 1.7; men, 0.8). The adjusted rate ratio for group A as compared with group C was 0.93 (95% confidence interval [CI], 0.74 to 1.18; P = 0.51) and for group B as compared with group C was 0.70 (95% CI, 0.55 to 0.88; P = 0.006). The percentage of HIV-positive participants with viral suppression at 24 months was 71.9% in group A, 67.5% in group B, and 60.2% in group C. The estimated percentage of HIV-positive adults in the community who were receiving ART at 36 months was 81% in group A and 80% in group B. CONCLUSIONS: A combination prevention intervention with ART provided according to local guidelines resulted in a 30% lower incidence of HIV infection than standard care. The lack of effect with universal ART was unanticipated and not consistent with the data on viral suppression. In this trial setting, universal testing and treatment reduced the population-level incidence of HIV infection. (Funded by the National Institute of Allergy and Infectious Diseases and others; HPTN 071 [PopArt] ClinicalTrials.gov number, NCT01900977.).


Asunto(s)
Antirretrovirales/uso terapéutico , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Administración Masiva de Medicamentos , Tamizaje Masivo , Adolescente , Adulto , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Incidencia , Masculino , Prevalencia , Sudáfrica/epidemiología , Carga Viral , Adulto Joven , Zambia/epidemiología
6.
BMC Health Serv Res ; 22(1): 503, 2022 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-35421966

RESUMEN

BACKGROUND: Across Sub-Saharan Africa, adolescents and young people (AYP) aged 15-24 have limited access to sexual and reproductive health (SRH) services, including HIV testing services (HTS). In response, the Yathu Yathu study was implemented in two high-density communities in Lusaka, Zambia. Yathu Yathu provides comprehensive, community-based, peer-led SRH services, including differentiated HTS (finger-prick and HIV self-testing) and comprehensive sexuality education (CSE). We describe adaptations to the Yathu Yathu intervention in response to the COVID-19 epidemic, and implications on uptake of HTS among AYP. METHODS: Yathu Yathu provides SRH services through community-based peer-led spaces. AYP in study communities were offered prevention points cards (PPC), which incentivizes and tracks service use. Social media (WhatsApp©/Facebook©) is used to engage and inform AYP about SRH. Due to COVID-19, hubs closed from April-June 2020. We describe adaptations in response to COVID-19 and, using routinely collected PPC data, describe uptake of HTS before (September 2019-March 2020) and after (July-December 2020) adaptations in response to COVID-19. We describe reach of the Yathu Yathu Facebook page and use qualitative data to describe AYP experiences of SRH service access. RESULTS: During hub closures, CSE was delivered via video on social media, resulting in an increase in Facebook page followers from 539(April) to 891(June). WhatsApp groups evolved as a platform to deliver CSE and COVID-19 information, with higher participation among young people aged 20-24. Key service delivery adaptations included: reducing the number of participants in hubs, mandatory handwashing before entry, use of personal protective equipment by staff and provision of facemasks to AYP. HTS were provided as normal. Adaptations led to fewer AYP attending hubs. Uptake of HTS among AYP visiting hubs for the first time after COVID-19-related closures was higher (73.2%) compared to uptake before adaptations (65.9%; adjOR=1.24 95%CI 0.99, 1.56, p=0.06). Despite disappointments with some aspects of service delivery, AYP expressed happiness that hubs had reopened. CONCLUSIONS: Social media can be a useful additional platform to reach AYP with HIV prevention information during COVID-19. With proper infection control in place, HTS can safely be provided to, accessed and accepted by AYP in community-based settings during COVID-19. TRIAL REGISTRATION: National Clinical Trials NCT04060420,19th August 2019. Current Controlled Trials ISRCTN75609016 , 14th September 2021, retrospectively registered.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , COVID-19 , Infecciones por VIH , Servicios de Salud Reproductiva , Adolescente , COVID-19/diagnóstico , COVID-19/epidemiología , COVID-19/prevención & control , Servicios de Salud Comunitaria , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Prueba de VIH , Humanos , Salud Reproductiva , Adulto Joven , Zambia/epidemiología
7.
BMC Pregnancy Childbirth ; 21(1): 663, 2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34592959

RESUMEN

BACKGROUND: Mobile phone-based interventions have been demonstrated in different settings to overcome barriers to accessing critical psychosocial support. In this study, we aimed to assess the acceptability and feasibility of a phone-based, peer-to-peer support group intervention for adolescent pregnant women aged 15-24 years living with HIV in Zambia. METHODS: Sixty-one consenting participants were recruited from Antenatal Clinics of two large urban communities in Lusaka. They were invited to participate in the mobile phone-based intervention that allowed them to anonymously communicate in a small group led by a facilitator for 4 months. A mixed methods approach was used to assess acceptability and feasibility, including a focus group discussion, pre- and post-intervention interview and analysis of the content of the text message data generated. RESULTS: Participants reported finding the platform "not hard to use" and enjoyed the anonymity of the groups. Seventy-one percent of participants (n = 43) participated in the groups, meaning they sent text messages to their groups. Approximately 12,000 text messages were sent by participants (an average of 169 messages/user and 6 mentors in 6 groups. Topics discussed were related to social support and relationships, stigma, HIV knowledge and medication adherence. CONCLUSION: The study showed that the intervention was acceptable and feasible, and highlighted the potential of the model for overcoming existing barriers to provision of psychosocial support to this population.


Asunto(s)
Teléfono Celular , Infecciones por VIH/psicología , Grupo Paritario , Complicaciones Infecciosas del Embarazo/psicología , Embarazo en Adolescencia/psicología , Sistemas de Apoyo Psicosocial , Apoyo Social/métodos , Adolescente , Femenino , Infecciones por VIH/etnología , Humanos , Proyectos Piloto , Embarazo , Complicaciones Infecciosas del Embarazo/etnología , Embarazo en Adolescencia/etnología , Envío de Mensajes de Texto , Adulto Joven , Zambia/etnología
8.
BMC Health Serv Res ; 21(1): 753, 2021 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-34325696

RESUMEN

BACKGROUND: Meeting the sexual and reproductive health (SRH) needs of adolescents and young people (AYP) requires their meaningful engagement in intervention design. We describe an iterative process of engaging AYP to finalise the design of a community-based, peer-led and incentivised SRH intervention for AYP aged 15-24 in Lusaka and the lessons learnt. METHODS: Between November 2018 and March 2019, 18 focus group discussions, eight in-depth interviews and six observations were conducted to assess AYP's knowledge of HIV/SRH services, factors influencing AYP's sexual behaviour and elicit views on core elements of a proposed intervention, including: community-based spaces (hubs) for service delivery, type of service providers and incentivising service use through prevention points cards (PPC; "loyalty" cards to gain points for accessing services and redeem these for rewards). A total of 230 AYP (15 participated twice in different research activities) and 21 adults (only participated in the community mapping discussions) participated in the research. Participants were purposively selected based on age, sex, where they lived and their roles in the study communities. Data were analysed thematically. RESULTS: Alcohol and drug abuse, peer pressure, poverty, unemployment and limited recreation facilities influenced AYP's sexual behaviours. Adolescent boys and young men lacked knowledge of contraceptive services and all AYP of pre and post exposure prophylaxis for HIV prevention. AYP stated a preference for accessing services at "hubs" located in the community rather than the health facility. AYP considered the age, sex and training of the providers when choosing whom they were comfortable accessing services from. PPCs were acceptable among AYP despite the loyalty card concept being new to them. AYP suggested financial and school support, electronic devices, clothing and food supplies as rewards. CONCLUSIONS: Engaging AYP in the design of an SRH intervention was feasible, informative and considered responsive to their needs. Although AYP's suggestions were diverse, the iterative process of AYP engagement facilitated the design of an intervention that is informed by AYP and implementable. TRIAL REGISTRATION: This formative study informed the design of this trial: ClinicalTrials.gov, NCT04060420. Registered 19 August, 2019.


Asunto(s)
Servicios de Salud Reproductiva , Salud Sexual , Adolescente , Humanos , Masculino , Salud Reproductiva , Conducta Sexual , Adulto Joven , Zambia
9.
PLoS Med ; 17(4): e1003067, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32240156

RESUMEN

BACKGROUND: In 2014, the Joint United Nations Programme on HIV/AIDS (UNAIDS) set the 90-90-90 targets: that 90% of people living with HIV know their HIV status, that 90% of those who know their HIV-positive status are on antiretroviral therapy (ART), and that 90% of those on treatment are virally suppressed. The aim was to reach these targets by 2020. We assessed the feasibility of achieving the first two targets, and the corresponding 81% ART coverage target, as part of the HIV Prevention Trials Network (HPTN) 071 Population Effects of Antiretroviral Therapy to Reduce HIV Transmission (PopART) community-randomized trial. METHODS AND FINDINGS: The study population was individuals aged ≥15 years living in 14 urban and peri-urban "PopART intervention" communities in Zambia and South Africa (SA), with a total population of approximately 600,000 and approximately 15% adult HIV prevalence. Community HIV care providers (CHiPs) delivered the PopART intervention during 2014-2017. This was a combination HIV prevention package including universal home-based HIV testing, referral of HIV-positive individuals to government HIV clinic services that offered universal ART (Arm A) or ART according to national guidelines (Arm B), and revisits to HIV-positive individuals to support linkage to HIV care and retention on ART. The intervention was delivered in 3 "rounds," each about 15 months long, during which CHiPs visited all households and aimed to contact all individuals aged ≥15 years at least once. In Arm A in Round 3 (R3), 67% (41,332/61,402) of men and 86% (56,345/65,896) of women in Zambia and 56% (17,813/32,095) of men and 71% (24,461/34,514) of women in SA participated in the intervention, among 193,907 residents aged ≥15 years. Following participation, HIV status was known by 90% of men and women in Zambia and by 78% of men and 85% of women in SA. The median time from CHiP referral of HIV-positive individuals to ART initiation was approximately 3 months. By the end of R3, an estimated 95% of HIV-positive women and 85% of HIV-positive men knew their HIV status, and among these individuals, approximately 90% of women and approximately 85% of men were on ART. ART coverage among all HIV-positive individuals was approximately 85% in women and approximately 75% in men, up from about 45% at the start of the study. ART coverage was lowest among men aged 18 to 34 and women aged 15 to 24 years, and among mobile individuals/in-migrants. Findings from Arm B were similar. The main limitations to our study were that estimates of testing and treatment coverage among men relied on considerable extrapolation because, in each round, approximately one-third of men did not participate in the PopART intervention; that our findings are for a service delivery model that was relatively intensive; and that we did not have comparable data from the 7 "standard-of-care" (Arm C) communities. CONCLUSIONS: Our study showed that very high HIV testing and treatment coverage can be achieved through persistent delivery of universal testing, facilitated linkage to HIV care, and universal treatment services. The ART coverage target of 81% was achieved overall, after 4 years of delivery of the PopART intervention, though important gaps remained among men and young people. Our findings are consistent with previously reported findings from southern and east Africa, extending their generalisability to urban settings with high rates of in-migration and mobility and to Zambia and SA. TRIAL REGISTRATION: ClinicalTrials.gov NCT01900977.


Asunto(s)
Antirretrovirales/uso terapéutico , Servicios de Salud Comunitaria/métodos , Infecciones por VIH/tratamiento farmacológico , Cobertura del Seguro/tendencias , Tamizaje Masivo/tendencias , Población Urbana/tendencias , Adolescente , Adulto , Anciano , Fármacos Anti-VIH/uso terapéutico , Femenino , Infecciones por VIH/epidemiología , Humanos , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , Sudáfrica/epidemiología , Factores de Tiempo , Adulto Joven , Zambia/epidemiología
10.
J Clin Microbiol ; 58(10)2020 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-32669382

RESUMEN

Viral genetic sequencing can be used to monitor the spread of HIV drug resistance, identify appropriate antiretroviral regimes, and characterize transmission dynamics. Despite decreasing costs, next-generation sequencing (NGS) is still prohibitively costly for routine use in generalized HIV epidemics in low- and middle-income countries. Here, we present veSEQ-HIV, a high-throughput, cost-effective NGS sequencing method and computational pipeline tailored specifically to HIV, which can be performed using leftover blood drawn for routine CD4 cell count testing. This method overcomes several major technical challenges that have prevented HIV sequencing from being used routinely in public health efforts; it is fast, robust, and cost-efficient, and generates full genomic sequences of diverse strains of HIV without bias. The complete veSEQ-HIV pipeline provides viral load estimates and quantitative summaries of drug resistance mutations; it also exploits information on within-host viral diversity to construct directed transmission networks. We evaluated the method's performance using 1,620 plasma samples collected from individuals attending 10 large urban clinics in Zambia as part of the HPTN 071-2 study (PopART Phylogenetics). Whole HIV genomes were recovered from 91% of samples with a viral load of >1,000 copies/ml. The cost of the assay (30 GBP per sample) compares favorably with existing VL and HIV genotyping tests, proving an affordable option for combining HIV clinical monitoring with molecular epidemiology and drug resistance surveillance in low-income settings.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , VIH-1 , Fármacos Anti-VIH/uso terapéutico , Farmacorresistencia Viral/genética , Genómica , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Carga Viral , Zambia
11.
BMC Infect Dis ; 20(1): 760, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-33059620

RESUMEN

BACKGROUND: A more stringent QuantiFERON-TB Gold In-Tube (QFT) conversion (from negative to positive) definition has been proposed to allow more definite detection of recent tuberculosis (TB) infection. We explored alternative conversion definitions to assist the interpretation of serial QFT results and estimate incidence of TB infection in a large cohort study. METHODS: We used QFT serial results from TB household contacts aged ≥15 years, collected at baseline and during two follow-up visits (2006-2011) as part of a cohort study in 24 communities in Zambia and South Africa (SA). Conversion rates using the manufacturers' definition (interferon-gamma (IFN-g) < 0.35 to ≥0.35, 'def1') were compared with stricter definitions (IFN-g < 0.2 to ≥0.7 IU/ml, 'def2'; IFN-g < 0.2 to ≥1.05 IU/ml, 'def3'; IFN-g < 0.2 to ≥1.4 IU/ml, 'def4'). Poisson regression was used for analysis. RESULTS: One thousand three hundred sixty-five individuals in Zambia and 822 in SA had QFT results available. Among HIV-negative individuals, the QFT conversion rate was 27.4 per 100 person-years (CI:22.9-32.6) using def1, 19.0 using def2 (CI:15.2-23.7), 14.7 using def3 (CI:11.5-18.8), and 12.0 using def4 (CI:9.2-15.7). Relative differences across def1-def4 were similar in Zambia and SA. Using def1, conversion was less likely if HIV positive not on antiretroviral treatment compared to HIV negative (aRR = 0.7, 95%CI = 0.4-0.9), in analysis including both countries. The same direction of associations were found using def 2-4. CONCLUSION: High conversion rates were found even with the strictest definition, indicating high incidence of TB infection among household contacts of TB patients in these communities. The trade-off between sensitivity and specificity using different thresholds of QFT conversion remains unknown due to the absence of a reference standard. However, we identified boundaries within which an appropriate definition might fall, and our strictest definition plausibly has high specificity.


Asunto(s)
Ensayos de Liberación de Interferón gamma/métodos , Tuberculosis/diagnóstico , Antirretrovirales/uso terapéutico , Estudios de Cohortes , Trazado de Contacto , Composición Familiar , Seropositividad para VIH , Humanos , Incidencia , Prevalencia , Sudáfrica/epidemiología , Tuberculosis/epidemiología , Zambia/epidemiología
12.
AIDS Behav ; 23(5): 1095-1103, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30737610

RESUMEN

Increased coverage of voluntary medical male circumcision (VMMC) is needed in countries with high HIV prevalence. We applied an HIV-prevention cascade to identify gaps in male circumcision coverage in Zambia. We used survey data collected in 2013 and 2014/15 to describe circumcision coverage at each time-point, and prevalence of variables related to demand for and supply of VMMC. We explored whether circumcision coverage in 2014/15 was associated with demand and supply among uncircumcised men in 2013. Results show that circumcision coverage was 11.5% in 2013 and 18.0% in 2014/15. Levels of having heard of circumcision and agreeing with prevention benefits was similar at both time-points (79.8% vs 83.2%, and 49.7% vs 50.7%, respectively). In 2013, 39.3% of men perceived services to be available compared to 54.7% in 2014/15. Levels of having heard of circumcision in 2013 was correlated with and higher perceived service availability associated with coverage in 2014/15. VMMC coverage was low in these study sites. Knowledge of prevention tools and of service availability are necessary to increase coverage but alone are insufficient.


Asunto(s)
Circuncisión Masculina , Atención a la Salud/organización & administración , Infecciones por VIH/prevención & control , Servicios Preventivos de Salud/organización & administración , Adolescente , Adulto , Circuncisión Masculina/estadística & datos numéricos , Análisis por Conglomerados , Humanos , Masculino , Persona de Mediana Edad , Aceptación de la Atención de Salud , Población Rural , Programas Voluntarios , Adulto Joven , Zambia/epidemiología
13.
AIDS Behav ; 23(4): 929-946, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30415432

RESUMEN

To achieve UNAIDS 90:90:90 targets at population-level, knowledge of HIV status must be followed by timely linkage to care, initiation and maintenance of antiretroviral therapy (ART) for all people living with HIV (PLHIV). Interpreting quantitative patterns using qualitative data, we investigate time taken to link to care and initiate ART amongst individuals aware of their HIV-status in high HIV-prevalence urban communities in the HPTN 071 (PopART) study, a community-randomised trial of a combination HIV prevention package, including universal testing and treatment, in 21 communities in Zambia and South Africa. Data are drawn from the seven intervention communities where immediate ART irrespective if CD4 count was offered from the trial-start in 2014. Median time from HIV-diagnosis to ART initiation reduced after 2 years of delivering the intervention from 10 to 6 months in both countries but varied by gender and community of residence. Social and health system realities impact decisions made by PLHIV about ART initiation.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa/métodos , Continuidad de la Atención al Paciente , Infecciones por VIH/tratamiento farmacológico , Accesibilidad a los Servicios de Salud , Tiempo de Tratamiento , Adolescente , Adulto , Anciano , Fármacos Anti-VIH/administración & dosificación , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Disparidades en Atención de Salud , Humanos , Masculino , Persona de Mediana Edad , Aceptación de la Atención de Salud , Prevalencia , Derivación y Consulta , Sudáfrica/epidemiología , Adulto Joven , Zambia/epidemiología
14.
PLoS Med ; 14(5): e1002292, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28464041

RESUMEN

BACKGROUND: The Joint United Nations Programme on HIV/AIDS (UNAIDS) 90-90-90 targets require that, by 2020, 90% of those living with HIV know their status, 90% of known HIV-positive individuals receive sustained antiretroviral therapy (ART), and 90% of individuals on ART have durable viral suppression. The HPTN 071 (PopART) trial is measuring the impact of a universal testing and treatment intervention on population-level HIV incidence in 21 urban communities in Zambia and South Africa. We report observational data from four communities in Zambia to assess progress towards the UNAIDS targets after 1 y of the PopART intervention. METHODS AND FINDINGS: The PopART intervention comprises annual rounds of home-based HIV testing delivered by community HIV-care providers (CHiPs) who also support linkage to care, ART retention, and other services. Data from four communities in Zambia receiving the full intervention (including immediate ART for all individuals with HIV) were used to determine proportions of participants who knew their HIV status after the CHiP visit; proportions linking to care and initiating ART following referral; and overall proportions of HIV-infected individuals who knew their status (first 90 target) and the proportion of these on ART (second 90 target), pre- and post-intervention. We are not able to assess progress towards the third 90 target at this stage of the study. Overall, 121,130 adults (59,283 men and 61,847 women) were enumerated in 46,714 households during the first annual round (December 2013 to June 2015). Of the 45,399 (77%) men and 55,703 (90%) women consenting to the intervention, 80% of men and 85% of women knew their HIV status after the CHiP visit. Of 6,197 HIV-positive adults referred by CHiPs, 42% (95% CI: 40%-43%) initiated ART within 6 mo and 53% (95% CI: 52%-55%) within 12 mo. In the entire population, the estimated proportion of HIV-positive adults who knew their status increased from 52% to 78% for men and from 56% to 87% for women. The estimated proportion of known HIV-positive individuals on ART increased overall from 54% after the CHiP visit to 74% by the end of the round for men and from 53% to 73% for women. The estimated overall proportion of HIV-positive adults on ART, irrespective of whether they knew their status, increased from 44% to 61%, compared with the 81% target (the product of the first two 90 targets). Coverage was lower among young men and women than in older age groups. The main limitation of the study was the need for assumptions concerning knowledge of HIV status and ART coverage among adults not consenting to the intervention or HIV testing, although our conclusions were robust in sensitivity analyses. CONCLUSIONS: In this analysis, acceptance of HIV testing among those consenting to the intervention was high, although linkage to care and ART initiation took longer than expected. Knowledge of HIV-positive status increased steeply after 1 y, almost attaining the first 90 target in women and approaching it in men. The second 90 target was more challenging, with approximately three-quarters of known HIV-positive individuals on ART by the end of the annual round. Achieving higher test uptake in men and more rapid linkage to care will be key objectives during the second annual round of the intervention. TRIAL REGISTRATION: ClinicalTrials.gov NCT01900977.


Asunto(s)
Antirretrovirales/uso terapéutico , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Adolescente , Adulto , Estudios de Cohortes , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Incidencia , Masculino , Tamizaje Masivo , Adulto Joven , Zambia/epidemiología
15.
Health Res Policy Syst ; 15(1): 51, 2017 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-28610616

RESUMEN

BACKGROUND: The extent to which routinely collected HIV data from Zambia has been used in peer-reviewed published articles remains unexplored. This paper is an analysis of peer-reviewed articles that utilised routinely collected HIV data from Zambia within six programme areas from 2004 to 2014. METHODS: Articles on HIV, published in English, listed in the Directory of open access journals, African Journals Online, Google scholar, and PubMed were reviewed. Only articles from peer-reviewed journals, that utilised routinely collected data and included quantitative data analysis methods were included. Multi-country studies involving Zambia and another country, where the specific results for Zambia were not reported, as well as clinical trials and intervention studies that did not take place under routine care conditions were excluded, although community trials which referred patients to the routine clinics were included. Independent extraction was conducted using a predesigned data collection form. Pooled analysis was not possible due to diversity in topics reviewed. RESULTS: A total of 69 articles were extracted for review. Of these, 7 were excluded. From the 62 articles reviewed, 39 focused on HIV treatment and retention in care, 15 addressed prevention of mother-to-child transmission, 4 assessed social behavioural change, and 4 reported on voluntary counselling and testing. In our search, no articles were found on condom programming or voluntary male medical circumcision. The most common outcome measures reported were CD4+ count, clinical failure or mortality. The population analysed was children in 13 articles, women in 16 articles, and both adult men and women in 33 articles. CONCLUSION: During the 10 year period of review, only 62 articles were published analysing routinely collected HIV data in Zambia. Serious consideration needs to be made to maximise the utility of routinely collected data, and to benefit from the funds and efforts to collect these data. This could be achieved with government support of operational research and publication of findings based on routinely collected Zambian HIV data.


Asunto(s)
Recolección de Datos/métodos , Bases de Datos Bibliográficas , Infecciones por VIH , Revisión de la Investigación por Pares , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Periodismo Médico , Masculino , Zambia
16.
Am J Epidemiol ; 183(2): 156-66, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26646292

RESUMEN

We aimed to model the incidence of infection with Mycobacterium tuberculosis among adults using data on infection incidence in children, disease prevalence in adults, and social contact patterns. We conducted a cross-sectional face-to-face survey of adults in 2011, enumerating "close" (shared conversation) and "casual" (shared indoor space) social contacts in 16 Zambian communities and 8 South African communities. We modeled the incidence of M. tuberculosis infection in all age groups using these contact patterns, as well as the observed incidence of M. tuberculosis infection in children and the prevalence of tuberculosis disease in adults. A total of 3,528 adults participated in the study. The reported rates of close and casual contact were 4.9 per adult per day (95% confidence interval: 4.6, 5.2) and 10.4 per adult per day (95% confidence interval: 9.3, 11.6), respectively. Rates of close contact were higher for adults in larger households and rural areas. There was preferential mixing of close contacts within age groups and within sexes. The estimated incidence of M. tuberculosis infection in adults was 1.5-6 times higher (2.5%-10% per year) than that in children. More than 50% of infections in men, women, and children were estimated to be due to contact with adult men. We conclude that estimates of infection incidence based on surveys in children might underestimate incidence in adults. Most infections may be due to contact with adult men. Treatment and control of tuberculosis in men is critical to protecting men, women, and children from tuberculosis.


Asunto(s)
Trazado de Contacto/estadística & datos numéricos , Conducta Social , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/transmisión , Adolescente , Adulto , Distribución por Edad , Niño , Preescolar , Estudios Transversales , Composición Familiar , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Modelos Teóricos , Mycobacterium tuberculosis , Prevalencia , Características de la Residencia , Distribución por Sexo , Sudáfrica/epidemiología , Adulto Joven , Zambia/epidemiología
17.
AIDS Care ; 28 Suppl 3: 99-107, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27421057

RESUMEN

This paper explores contextual heterogeneity within a community randomised trial HPTN 071 (Population Effects of Antiretroviral Treatment to Reduce HIV Transmission) carried out in 21 study communities (12 Zambian, 9 South African). The trial evaluates the impact of a combination HIV prevention package (including household-based HIV counselling and testing and anti-retroviral treatment (ART) eligibility regardless of CD4-count) on HIV incidence. The selection, matching and randomisation of study communities relied on key epidemiological and demographic variables and community and stakeholder support. In 2013, following the selection of study communities, a "Broad Brush Survey" (BBS) approach was used to rapidly gather qualitative data on each study community, prior to the implementation of the trial intervention. First-year process indicator intervention data (2014-2015) were collected during the household-based intervention by community lay workers. Using an open/closed typology of urban communities (indicating more or less heterogeneity), this qualitative inquiry presents key features of 12 Zambian communities using a list of four meta-indicators (physical features, social organisation, networks and community narratives). These indicators are then compared with four intervention process indicators in a smaller set of four study communities. The process indicators selected for this analysis indicate response to the intervention (uptake) amongst adults. The BBS qualitative data are used to interpret patterns of similarity and variability in the process indicators across four communities. We found that meta-indicators of local context helped to interpret patterns of similarity and variability emerging across and within the four communities. Features especially significant for influencing heterogeneity in process indicators include proportion of middle-class residents, proximity to neighbouring communities and town centre, the scale of the informal economy, livelihood-linked mobility, presence of HIV stakeholders over time and commitment to community action. Future interdisciplinary analysis is needed to explore if these patterns of difference continue to hold up over the full intervention period and all intervention communities.


Asunto(s)
Antirretrovirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Características de la Residencia , Adulto , Investigación Participativa Basada en la Comunidad , Consejo , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , Conocimientos, Actitudes y Práctica en Salud , Humanos , Incidencia , Masculino , Sudáfrica/epidemiología , Zambia/epidemiología
19.
Trop Med Int Health ; 20(11): 1492-1500, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26224169

RESUMEN

OBJECTIVE: The prevalence of MDR-TB in Zambia was estimated to be 1.8% in 2001. A second drug resistance survey was conducted in 2008 to determine trends; the use of the Genotype MTBDRplus assay was applied to compare results to the gold standard. METHOD: A two-stage cluster sampling, with health facilities as primary sampling units. Processed sputum specimens were inoculated on solid media for culture; heat-inactivated bacterial suspensions from sputum samples were tested on a commercial line probe assay for the identification of rifampicin and isoniazid resistance. RESULTS: A total of 917 patients with TB were enrolled and 883 (96.3%) analysed. A total of 574 (65%) had LJ results and 824 (93.3%) had results from MTBDRplus assay. The median age was 32, and 63.3% were males. MDR-TB according to LJ-based DST was 1.1% (CI 0.1-2.4) whereas according to MDTBDRplus assay was 1.6% (CI 0.6-2.6). Isoniazid monoresistance in new cases was 2.4% (CI 0.613-4.26) based on LJ results and 5.0% (CI 3.2-6.7) based on the MTBDRplus; in retreatment cases, it was 4.4% (CI 0.3-8.6) and 2.40% (CI <0.1-5.1) on LJ and MTBDRplus, respectively. Rifampicin monoresistance in new cases was 0.1% (CI <0.1-0.4) based on LJ and 0.6% (CI 0.01-1.1) based on the MTBDRplus; in retreatment cases, it was 0% (CI 0-3.8) and 1.8% (CI <0.1-4.0) on LJ and MTBDRplus, respectively. There were no XDR-TB cases found and no association between MDR-TB and HIV. CONCLUSION: There was no increase in MDR-TB prevalence in Zambia from 2001 to 2008; results from the two methods were similar. Molecular methods were quicker and simpler to use.

20.
Lancet ; 382(9899): 1183-94, 2013 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-23915882

RESUMEN

BACKGROUND: Southern Africa has had an unprecedented increase in the burden of tuberculosis, driven by the HIV epidemic. The Zambia, South Africa Tuberculosis and AIDS Reduction (ZAMSTAR) trial examined two public health interventions that aimed to reduce the burden of tuberculosis by facilitating either rapid sputum diagnosis or integrating tuberculosis and HIV services within the community. METHODS: ZAMSTAR was a community-randomised trial done in Zambia and the Western Cape province of South Africa. Two interventions, community-level enhanced tuberculosis case-finding (ECF) and household level tuberculosis-HIV care, were implemented between Aug 1, 2006, and July 31, 2009, and assessed in a 2×2 factorial design between Jan 9, 2010, and Dec 6, 2010. All communities had a strengthened tuberculosis-HIV programme implemented in participating health-care centres. 24 communities, selected according to population size and tuberculosis notification rate, were randomly allocated to one of four study groups using a randomisation schedule stratified by country and baseline prevalence of tuberculous infection: group 1 strengthened tuberculosis-HIV programme at the clinic alone; group 2, clinic plus ECF; group 3, clinic plus household intervention; and group 4, clinic plus ECF and household interventions. The primary outcome was the prevalence of culture-confirmed pulmonary tuberculosis in adults (≥18 years), defined as Mycobacterium tuberculosis isolated from one respiratory sample, measured 4 years after the start of interventions in a survey of 4000 randomly selected adults in each community in 2010. The secondary outcome was the incidence of tuberculous infection, measured using tuberculin skin testing in a cohort of schoolchildren, a median of 4 years after a baseline survey done before the start of interventions. This trial is registered, number ISRCTN36729271. FINDINGS: Prevalence of tuberculosis was evaluated in 64,463 individuals randomly selected from the 24 communities; 894 individuals had active tuberculosis. Averaging over the 24 communities, the geometric mean of tuberculosis prevalence was 832 per 100,000 population. The adjusted prevalence ratio for the comparison of ECF versus non-ECF intervention groups was 1·09 (95% CI 0·86-1·40) and of household versus non-household intervention groups was 0·82 (0·64-1·04). The incidence of tuberculous infection was measured in a cohort of 8809 children, followed up for a median of 4 years; the adjusted rate ratio for ECF versus non-ECF groups was 1·36 (95% CI 0·59-3·14) and for household versus non-household groups was 0·45 (0·20-1·05). INTERPRETATION: Although neither intervention led to a statistically significant reduction in tuberculosis, two independent indicators of burden provide some evidence of a reduction in tuberculosis among communities receiving the household intervention. By contrast the ECF intervention had no effect on either outcome. FUNDING: Bill & Melinda Gates Foundation.


Asunto(s)
Atención Ambulatoria/métodos , Servicios de Salud Comunitaria/organización & administración , Infecciones por VIH/epidemiología , Tuberculosis Pulmonar/epidemiología , Adolescente , Adulto , Distribución por Edad , Anciano , Coinfección/epidemiología , Femenino , Infecciones por VIH/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Distribución por Sexo , Sudáfrica/epidemiología , Tuberculosis Pulmonar/prevención & control , Adulto Joven , Zambia/epidemiología
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