ABSTRACT
BACKGROUND: Tuberculosis (TB) continues to be a major cause of death across sub-Saharan Africa (SSA). In parallel, non-communicable disease and especially cardiovascular disease (CVD) burden has increased substantially in the region. Cardiac manifestations of TB are well-recognised but the extent to which they co-exist with pulmonary TB (PTB) has not been systematically evaluated. The aim of this study is to improve understanding of the burden of cardiac pathology in PTB in those living with and without HIV in a high-burden setting. METHODS: This is a cross-sectional and natural history study to evaluate the burden and natural history of cardiac pathology in participants with PTB in Lusaka, Zambia, a high burden setting for TB and HIV. Participants with PTB, with and without HIV will be consecutively recruited alongside age- and sex-matched TB-uninfected comparators on a 2:1 basis. Participants will undergo baseline assessments to collect clinical, socio-demographic, functional, laboratory and TB disease impact data followed by point-of-care and standard echocardiography. Participants with PTB will undergo further repeat clinical and functional examination at two- and six months follow-up. Those with cardiac pathology at baseline will undergo repeat echocardiography at six months. DISCUSSION: The outcomes of the study are to a) determine the burden of cardiac pathology at TB diagnosis, b) describe its association with patient-defining risk factors and biochemical markers of cardiac injury and stretch and c) describe the natural history of cardiac pathology during the course of TB treatment.
Subject(s)
HIV Infections , Tuberculosis , Humans , Zambia/epidemiology , HIV Infections/diagnosis , HIV Infections/epidemiology , HIV Infections/complications , Prevalence , Cross-Sectional Studies , Tuberculosis/complications , Tuberculosis/epidemiologyABSTRACT
BACKGROUND: Tuberculosis (TB) prevalence remains persistently high in many settings, with new or expanded interventions required to achieve substantial reductions. The HIV Prevention Trials Network (HPTN) 071 (PopART) community-randomised trial randomised 14 communities to receive the "PopART" intervention during 2014 to 2017 (7 arm A and 7 arm B communities) and 7 communities to receive standard-of-care (arm C). The intervention was delivered door-to-door by community HIV care providers (CHiPs) and included universal HIV testing, facilitated linkage to HIV care at government health clinics, and systematic TB symptom screening. The Tuberculosis Reduction through Expanded Anti-retroviral Treatment and Screening (TREATS) study aimed to measure the impact of delivering the PopART intervention on TB outcomes, in communities with high HIV and TB prevalence. METHODS AND FINDINGS: The study population of the HPTN 071 (PopART) trial included individuals aged ≥15 years living in 21 urban and peri-urban communities in Zambia and South Africa, with a total population of approximately 1 million and an adult HIV prevalence of around 15% at the time of the trial. Two sputum samples for TB testing were provided to CHiPs by individuals who reported ≥1 TB suggestive symptom (a cough for ≥2 weeks, unintentional weight loss ≥1.5 kg in the last month, or current night sweats) or that a household member was currently on TB treatment. Antiretroviral therapy (ART) was offered universally at clinics in arm A and according to local guidelines in arms B and C. The TREATS study was conducted in the same 21 communities as the HPTN 071 (PopART) trial between 2017 and 2022, and TB prevalence was a co-primary endpoint of the TREATS study. The primary comparison was between the PopART intervention (arms A and B combined) and the standard-of-care (arm C). During 2019 to 2021, a TB prevalence survey was conducted among randomly selected individuals aged ≥15 years (approximately 1,750 per community in arms A and B, approximately 3,500 in arm C). Participants were screened on TB symptoms and chest X-ray, with diagnostic testing using Xpert-Ultra followed by culture for individuals who screened positive. Sputum eligibility was determined by the presence of a cough for ≥2 weeks, or ≥2 of 5 "TB suggestive" symptoms (cough, weight loss for ≥4 weeks, night sweats, chest pain, and fever for ≥2 weeks), or chest X-ray CAD4TBv5 score ≥50, or no available X-ray results. TB prevalence was compared between trial arms using standard methods for cluster-randomised trials, with adjustment for age, sex, and HIV status, and multiple imputation was used for missing data on prevalent TB. Among 83,092 individuals who were eligible for the survey, 49,556 (59.6%) participated, 8,083 (16.3%) screened positive, 90.8% (7,336/8,083) provided 2 sputum samples for Xpert-Ultra testing, and 308 (4.2%) required culture confirmation. Overall, estimated TB prevalence was 0.92% (457/49,556). The geometric means of 7 community-level prevalence estimates were 0.91%, 0.70%, and 0.69% in arms A, B, and C, respectively, with no evidence of a difference comparing arms A and B combined with arm C (adjusted prevalence ratio 1.14, 95% confidence interval, CI [0.67, 1.95], p = 0.60). TB prevalence was higher among people living with HIV than HIV-negative individuals, with an age-sex-community adjusted odds ratio of 2.29 [95% CI 1.54, 3.41] in Zambian communities and 1.61 [95% CI 1.13, 2.30] in South African communities. The primary limitations are that the study was powered to detect only large reductions in TB prevalence in the intervention arm compared with standard-of-care, and the between-community variation in TB prevalence was larger than anticipated. CONCLUSIONS: There was no evidence that the PopART intervention reduced TB prevalence. Systematic screening for TB that is based on symptom screening alone may not be sufficient to achieve a large reduction in TB prevalence over a period of several years. Including chest X-ray screening alongside TB symptom screening could substantially increase the sensitivity of systematic screening for TB. TRIAL REGISTRATION: The TREATS study was registered with ClinicalTrials.gov Identifier: NCT03739736 on November 14, 2018. The HPTN 071 (PopART) trial was registered at ClinicalTrials.gov under number NCT01900977 on July 17, 2013.
Subject(s)
HIV Infections , HIV , Adult , Humans , South Africa/epidemiology , Zambia/epidemiology , Cross-Sectional Studies , Cough , Prevalence , HIV Infections/diagnosis , HIV Infections/drug therapy , HIV Infections/epidemiology , Research DesignABSTRACT
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.
Subject(s)
Tuberculosis , Humans , Zambia/epidemiology , South Africa/epidemiology , Prevalence , Cross-Sectional Studies , X-Rays , Sensitivity and Specificity , Tuberculosis/diagnostic imaging , Tuberculosis/epidemiologyABSTRACT
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.
Subject(s)
COVID-19 , SARS-CoV-2 , Humans , COVID-19 Testing , Cross-Sectional Studies , Lesotho , Pandemics , Zambia , Community Health WorkersABSTRACT
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.).
Subject(s)
Anti-Retroviral Agents/therapeutic use , HIV Infections/diagnosis , HIV Infections/drug therapy , Mass Drug Administration , Mass Screening , Adolescent , Adult , Female , HIV Infections/epidemiology , HIV Infections/prevention & control , Humans , Incidence , Male , Prevalence , South Africa/epidemiology , Viral Load , Young Adult , Zambia/epidemiologyABSTRACT
BACKGROUND: Multi-assay algorithms (MAAs) are used to estimate population-level HIV incidence and identify individuals with recent infection. Many MAAs use low viral load (VL) as a biomarker for long-term infection. This could impact incidence estimates in settings with high rates of early HIV treatment initiation. We evaluated the performance of two MAAs that do not include VL. METHODS: Samples were collected from 219 seroconverters (infected < 1 year) and 4376 non-seroconverters (infected > 1 year) in the HPTN 071 (PopART) trial; 28.8% of seroconverter samples and 73.2% of non-seroconverter samples had VLs ≤ 400 copies/mL. Samples were tested with the Limiting Antigen Avidity assay (LAg) and JHU BioRad-Avidity assays. Antibody reactivity to two HIV peptides was measured using the MSD U-PLEX assay. Two MAAs were evaluated that do not include VL: a MAA that includes the LAg-Avidity assay and BioRad-Avidity assay (LAg + BR) and a MAA that includes the LAg-Avidity assay and two peptide biomarkers (LAg + PepPair). Performance of these MAAs was compared to a widely used MAA that includes LAg and VL (LAg + VL). RESULTS: The incidence estimate for LAg + VL (1.29%, 95% CI: 0.97-1.62) was close to the observed longitudinal incidence (1.34% 95% CI: 1.17-1.53). The incidence estimates for the other two MAAs were higher (LAg + BR: 2.56%, 95% CI 2.01-3.11; LAg + PepPair: 2.84%, 95% CI: 1.36-4.32). LAg + BR and LAg + PepPair also misclassified more individuals infected > 2 years as recently infected than LAg + VL (1.2% [42/3483 and 1.5% [51/3483], respectively, vs. 0.2% [6/3483]). LAg + BR classified more seroconverters as recently infected than LAg + VL or LAg + PepPair (80 vs. 58 and 50, respectively) and identified ~ 25% of virally suppressed seroconverters as recently infected. CONCLUSIONS: The LAg + VL MAA produced a cross-sectional incidence estimate that was closer to the longitudinal estimate than two MAAs that did not include VL. The LAg + BR MAA classified the greatest number of individual seroconverters as recently infected but had a higher false recent rate.
Subject(s)
HIV Infections , Humans , Cross-Sectional Studies , Incidence , HIV Infections/drug therapy , HIV Infections/epidemiology , Immunoenzyme Techniques , Anti-Retroviral Agents/therapeutic use , Viral Load , Algorithms , BiomarkersABSTRACT
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.
Subject(s)
Reproductive Health Services , Sexual Health , Adolescent , Humans , Male , Reproductive Health , Sexual Behavior , Young Adult , ZambiaABSTRACT
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.
Subject(s)
Anti-Retroviral Agents/therapeutic use , Community Health Services/methods , HIV Infections/drug therapy , Insurance Coverage/trends , Mass Screening/trends , Urban Population/trends , Adolescent , Adult , Aged , Anti-HIV Agents/therapeutic use , Female , HIV Infections/epidemiology , Humans , Male , Mass Screening/methods , Middle Aged , South Africa/epidemiology , Time Factors , Young Adult , Zambia/epidemiologyABSTRACT
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.
Subject(s)
Interferon-gamma Release Tests/methods , Tuberculosis/diagnosis , Anti-Retroviral Agents/therapeutic use , Cohort Studies , Contact Tracing , Family Characteristics , HIV Seropositivity , Humans , Incidence , Prevalence , South Africa/epidemiology , Tuberculosis/epidemiology , Zambia/epidemiologyABSTRACT
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.
Subject(s)
Anti-HIV Agents/therapeutic use , Antiretroviral Therapy, Highly Active/methods , Continuity of Patient Care , HIV Infections/drug therapy , Health Services Accessibility , Time-to-Treatment , Adolescent , Adult , Aged , Anti-HIV Agents/administration & dosage , CD4 Lymphocyte Count , Female , HIV Infections/diagnosis , HIV Infections/epidemiology , Healthcare Disparities , Humans , Male , Middle Aged , Patient Acceptance of Health Care , Prevalence , Referral and Consultation , South Africa/epidemiology , Young Adult , Zambia/epidemiologyABSTRACT
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.
Subject(s)
Anti-Retroviral Agents/therapeutic use , HIV Infections/diagnosis , HIV Infections/drug therapy , Adolescent , Adult , Cohort Studies , Female , HIV Infections/epidemiology , HIV Infections/prevention & control , Humans , Incidence , Male , Mass Screening , Young Adult , Zambia/epidemiologyABSTRACT
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.
Subject(s)
Contact Tracing/statistics & numerical data , Social Behavior , Tuberculosis, Pulmonary/epidemiology , Tuberculosis, Pulmonary/transmission , Adolescent , Adult , Age Distribution , Child , Child, Preschool , Cross-Sectional Studies , Family Characteristics , Female , Humans , Incidence , Male , Middle Aged , Models, Theoretical , Mycobacterium tuberculosis , Prevalence , Residence Characteristics , Sex Distribution , South Africa/epidemiology , Young Adult , Zambia/epidemiologyABSTRACT
Key to the success of a HIV combination prevention strategy, including galvanizing the current push to roll out universal test and treat (UTT), is the involvement and buy-in of the populations that the strategy aims to reach. Drawing on the experiences of engaging with 21 communities in Zambia and South Africa in the design and implementation of a community-randomized study of combination HIV prevention including UTT, this paper reflects on the commitment to, approaches for and benefits of involving communities. Key lessons learnt include that all communities require continuous community engagement (CE) and engagement needs to be adapted to diverse local contexts. Intrinsic goals of CE, such as building trusting relationships between study stakeholders, are necessary precursors to instrumental goals which strengthen the research quality. Engaging the community for combination prevention requires that CE successfully bridges science and real life, paying attention to influences in the wider social landscape.
Subject(s)
Anti-Retroviral Agents/therapeutic use , Behavior Therapy , HIV Infections/drug therapy , HIV Infections/prevention & control , Mass Screening/methods , Randomized Controlled Trials as Topic , Acquired Immunodeficiency Syndrome , Adolescent , Adult , Circumcision, Male , Community-Based Participatory Research , Condoms/statistics & numerical data , Female , HIV Infections/diagnosis , HIV Infections/epidemiology , Humans , Male , Patient Acceptance of Health Care , Program Evaluation , Residence Characteristics , South Africa/epidemiology , Treatment Outcome , Zambia/epidemiologyABSTRACT
BACKGROUND: In high incidence settings, the majority of Mycobacterium tuberculosis (M.tb) transmission occurs outside the household. Little is known about where people's indoor contacts occur outside the household, and how this differs between different settings. We estimate the number of contact hours that occur between adults and adult/youths and children in different building types in urban areas in Western Cape, South Africa, and Zambia. METHODS: Data were collected from 3206 adults using a cross-sectional survey, on buildings visited in a 24-h period, including building function, visit duration, and number of adults/youths and children (5-12 years) present. The mean numbers of contact hours per day by building function were calculated. RESULTS: Adults in Western Cape were more likely to visit workplaces, and less likely to visit shops and churches than adults in Zambia. Adults in Western Cape spent longer per visit in other homes and workplaces than adults in Zambia. More adults/youths were present at visits to shops and churches in Western Cape than in Zambia, and fewer at homes and hairdressers. More children were present at visits to shops in Western Cape than in Zambia, and fewer at schools and hairdressers. Overall numbers of adult/youth indoor contact hours were the same at both sites (35.4 and 37.6 h in Western Cape and Zambia respectively, p = 0.4). Child contact hours were higher in Zambia (16.0 vs 13.7 h, p = 0.03). Adult/youth and child contact hours were highest in workplaces in Western Cape and churches in Zambia. Compared to Zambia, adult contact hours in Western Cape were higher in workplaces (15.2 vs 8.0 h, p = 0.004), and lower in churches (3.7 vs 8.6 h, p = 0.002). Child contact hours were higher in other peoples' homes (2.8 vs 1.6 h, p = 0.03) and workplaces (4.9 vs 2.1 h, p = 0.003), and lower in churches (2.5 vs 6.2, p = 0.004) and schools (0.4 vs 1.5, p = 0.01). CONCLUSIONS: Patterns of indoor contact between adults and adults/youths and children differ between different sites in high M.tb incidence areas. Targeting public buildings with interventions to reduce M.tb transmission (e.g. increasing ventilation or UV irradiation) should be informed by local data.
Subject(s)
Residence Characteristics , Tuberculosis/prevention & control , Adult , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Incidence , Interpersonal Relations , Male , Mycobacterium tuberculosis , Schools , South Africa/epidemiology , Tuberculosis/transmission , Workplace , Zambia/epidemiologyABSTRACT
For the last three decades, sub-Saharan Africa has been the epicentre of the HIV epidemic. Some key drivers of the epidemic are specific to this region and there is an urgent need to develop context-specific strategies to reduce HIV-related burden. Implementation frameworks should endeavour to combine structural, behavioural and biomedical interventions and the future of the HIV response involves embracing different approaches for different populations; it is not 'one-size fits all approach'. Expanded use of community-based interventions will be key in expanding the role of antiretroviral treatment as prevention (TasP) in the region. For TasP to be effective, high antiretroviral therapy (ART) coverage rates need to be attained. Data from programmatic trials currently underway will provide crucial data to guide the future implementation of TasP.
Subject(s)
Delivery of Health Care/organization & administration , HIV Infections/prevention & control , Africa South of the Sahara/epidemiology , Anti-HIV Agents/therapeutic use , Combined Modality Therapy , Community Health Services/organization & administration , HIV Infections/epidemiology , Health Plan Implementation , HumansABSTRACT
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.
Subject(s)
Ambulatory Care/methods , Community Health Services/organization & administration , HIV Infections/epidemiology , Tuberculosis, Pulmonary/epidemiology , Adolescent , Adult , Age Distribution , Aged , Coinfection/epidemiology , Female , HIV Infections/prevention & control , Humans , Male , Middle Aged , Prevalence , Sex Distribution , South Africa/epidemiology , Tuberculosis, Pulmonary/prevention & control , Young Adult , Zambia/epidemiologyABSTRACT
Calls to decolonize global health have highlighted the continued existence of colonial structures in research into diseases of public health importance particularly in low- and middle-income countries (LMICs). A key step towards restructuring the system and shaping it to local needs is equitable leadership in global health partnerships. This requires ensuring that researchers in LMICs are given the opportunity to successfully secure grant funding to lead and drive their own research based on locally defined priorities. In February 2022, the London School of Hygiene and Tropical Medicine hosted a workshop aimed at bringing together funders and early- and mid-career researchers (EMCRs) to identify funder initiatives that have worked to improve equitable leadership, to better understand barriers faced by researchers, and collectively brainstorm approaches to overcome these barriers. The workshop transcript was analyzed using a deductive thematic approach based on the workshop topic to identify key emerging themes. Barriers identified were the lack of individual and institutional level support and flawed funding structures for EMCRs in LMIC settings. Strategies on how equitable leadership can be further facilitated include institutional reforms for funders to facilitate equity, diversity, and inclusion in their partners through consultative engagement and in addition, reshaping how research priorities are defined; diversified funding streams for research organizations, building partnerships and dedicated funding for capacity building of EMCRs. Intentional advances to overcome funding barriers in global health speak directly to its decolonization. Urgently required and complex changes in practice must be intentional and do require uncomfortable shifts which will take time. Supplementary Information: The online version contains supplementary material available at 10.1186/s44263-024-00047-4.
ABSTRACT
INTRODUCTION: The HPTN071 (PopART) for Youth (P-ART-Y) study evaluated the acceptability and uptake of a community-level combination HIV prevention package including universal testing and treatment (UTT) among young people in Zambia and South Africa. We determined whether a four-question primary care level screening tool, validated for use in clinical settings, could enhance community (door-to-door) identification of undiagnosed HIV-positive younger adolescents (aged 10-14) who are frequently left out of HIV interventions. METHOD: Community HIV-care Providers (CHiPs) contacted and consented adolescents in their homes and offered them participation in the PopART intervention. CHiPs used a four question-screening tool, which included: history of hospital admission; recurring skin problems; poor health in last 3 months; and death of at least one parent. A "yes" response to one or more questions was classified as being "at risk" of being HIV-positive. Rapid HIV tests were offered to all children. Data were captured through an electronic data capture device from August 2016 to December 2017. The sensitivity, specificity, positive predictive value and negative predictive value were estimated for the screening tool, using the rapid HIV test result as the gold standard. RESULTS: In our 14 study sites, 33,710 adolescents aged 10-14 in Zambia and 8,610 in South Africa participated in the study. About 1.3% (427/33,710) and 1.2% (106/8,610) self-reported to be HIV positive. Excluding the self-reported HIV-positive, we classified 11.3% (3,746/33,283) of adolescents in Zambia and 17.5% (1,491/8,504) in South Africa as "at risk". In Zambia the estimated sensitivity was 35.3% (95% CI 27.3%-44.2%) and estimated specificity was 88.9% (88.5%-89.2%). In South Africa the sensitivity was 72.3% (26.8%-94.9%) and specificity was 82.5% (81.6-83.4%). CONCLUSION: The sensitivity of the screening tool in a community setting in Zambia was low, so this tool should not be considered a substitute for universal testing where that is possible. In South Africa the sensitivity was higher, but with a wide confidence interval. Where universal testing is not possible the tool may help direct resources to adolescents more likely to be living with undiagnosed HIV. TRIAL REGISTRATION: Clinical Trial Number: NCT01900977.
Subject(s)
HIV Infections , Child , Humans , Adolescent , Zambia/epidemiology , South Africa/epidemiology , HIV Infections/diagnosis , HIV Infections/epidemiology , HIV Infections/drug therapy , Mass Screening , Predictive Value of TestsABSTRACT
OBJECTIVES: Pandemic response in low-income countries (LICs) or settings often suffers from scarce epidemic surveillance and constrained mitigation capacity. The drivers of pandemic burden in such settings, and the impact of limited and delayed interventions remain poorly understood. METHODS: We analysed COVID-19 seroprevalence and all-cause excess deaths data from the peri-urban district of Kabwe, Zambia between March 2020 and September 2021 with a novel mathematical model. Data encompassed three consecutive waves caused by the wild-type, Beta and Delta variants. RESULTS: Across all three waves, we estimated a high cumulative attack rate, with 78% (95% credible interval [CrI] 71-85) of the population infected, and a high all-cause excess mortality, at 402 (95% CrI 277-473) deaths per 100,000 people. Ambitiously improving health care to a capacity similar to that in high-income settings could have averted up to 46% (95% CrI 41-53) of accrued excess deaths, if implemented from June 2020 onward. An early and accelerated vaccination rollout could have achieved the highest reductions in deaths. Had vaccination started as in some high-income settings in December 2020 and with the same daily capacity (doses per 100 population), up to 68% (95% CrI 64-71) of accrued excess deaths could have been averted. Slower rollouts would have still averted 62% (95% CrI 58-68), 54% (95% CrI 49-61) or 26% (95% CrI 20-38) of excess deaths if matching the average vaccination capacity of upper-middle-, lower-middle- or LICs, respectively. CONCLUSIONS: Robust quantitative analyses of pandemic data are of pressing need to inform future global pandemic preparedness commitments.
ABSTRACT
One quarter of the world's population is estimated to be infected with Mycobacterium tuberculosis. Identifying recent TB infection (TBI) offers an avenue to targeted TB preventative therapy provision, and prevention to disease progression. However, detecting recent TBI remains challenging. The QuantiFERON-TB Gold Plus assay (QFT-Plus) claims to have improved sensitivity in detecting recent TBI, by the addition of the TB2 antigen tube to the TB1 tube used in previous tests. TB2 detects CD8-mediated interferon gamma response, a potential marker of recent infection. We compared QFT-Plus TB1 and TB2 responses in individuals with recent and remote infection in high-burden settings. The Tuberculosis Reduction through Expanded Antiretroviral Treatment and TB Screening (TREATS) Project followed a cohort of adolescents and young people (AYP) aged 15-24 years in Zambia and South Africa to determine TBI incidence measured by QFT-Plus over 24 months. We categorised individuals with QTF-Plus positive result into recent and remote infection. We compared their TB1 and TB2 responses and the antigen tube differential [TB2-TB1], an indicator of CD8-activity, using logistic regression. At baseline, 3876 AYP, 1852/3876 (47.8%) were QFT-Plus positive whilst 2024/3876 (52.2%) QFT-Plus negative. Of the QFT-Plus baseline positives, 1069/1852 (57.7%) tested positive at both 12 and 24 months-remote infection. Of the QFT-Plus baseline negatives, 274/2024(13.3%) converted within a 12-month period- recent infection. TB1 and TB2 responses were higher in remote than recent infection. In recent infection, TB2 responses were greater than TB1 responses. The mean differential was 0.01 IU/ml in recent and -0.22 IU/ml in remote infection, (p = 0.145). The quantitative QFT-Plus results did not appear to reflect a marked distinction between recent and remote infection. Further analysis of the responses of infected individuals who developed disease is required to determine whether any signal in QFT-Plus results may predict progression to disease.