High incidence of tuberculosis in young children living with HIV in the Western Cape, South Africa.

Background: Data on tuberculosis (TB) incidence and risk factors among children living with HIV (CLHIV) in the universal ART era are limited.

Methods: We analysed routinely-collected data on TB diagnoses for CLHIV age ≤5 years, born 2018-2022, in the Westen Cape, South Africa. We examined factors associated with TB diagnosis, with death and loss to follow-up as competing events.

The Retrospective Implementation of Standardized In Utero HIV Exposure Definitions Using Routinely Collected Public Sector Data Across the Western Cape Province, South Africa.

Using the Data Evaluation and Preparation for HIV-Exposed Uninfected Child Cohorts project's standardized child HIV exposure definitions, 64%, 64% and 90% of children exposed to HIV in utero could be classified as HIV-uninfected with moderate or high certainty at the ages of 1 and 3 years and at the time of first infectious disease hospitalization, respectively. These definitions can be applied retrospectively to routine datasets with linked mother-child data.

HIV Drug Resistance in Newly Diagnosed Young Children in the Western Cape, South Africa.

Background: Pretreatment of HIV drug resistance among children living with HIV (CLHIV) can compromise antiretroviral therapy (ART) effectiveness. Resistance may be transmitted directly from mothers or acquired following exposure to antiretrovirals consumed through breastfeeding or administered as prophylaxis.

Methods: We performed resistance testing in children aged <3 years, newly diagnosed with HIV in Western Cape, South Africa (2021-2022), who either (1) acquired HIV via possible breastfeeding transmission from mothers who received ART (any regimen) during pregnancy/postpartum and/or (2) were exposed to protease inhibitors or integrase strand transfer inhibitors (INSTIs) in utero.

Severe outcomes among adults with TB during COVID-19.

Background: The COVID-19 pandemic prompted strict public health measures to reduce SARS-CoV-2 transmission, potentially interrupting TB programmes in the Western Cape, South Africa.

Methods: We conducted a retrospective cohort study, estimating changes in new TB case rates and risk of death during TB-specific admissions within 6 months of TB first evidence, during the pre-pandemic (1 January 2019-26 March 2020) and after the implementation of public health and social measures (PHSM) periods (26 March 2020-30 September 2021), based on PHSM strictness. We used interrupted time series and logistic regression models to adjust for key characteristics.

Correcting mortality estimates among children and youth on antiretroviral therapy in southern Africa: A comparative analysis between a multi-country tracing study and linkage to a health information exchange.

Objectives: The objective of this study is to assess the outcomes of children, adolescents and young adults with HIV reported as lost to follow-up, correct mortality estimates for children, adolescents and young adults with HIV for unascertained outcomes in those loss to follow-up (LTFU) based on tracing and linkage data separately using data from the International epidemiology Databases to Evaluate AIDS in Southern Africa.

Methods: We included data from two different populations of children, adolescents and young adults with HIV; (1) clinical data from children, adolescents and young adults with HIV aged ≤24 years from Lesotho, Malawi, Mozambique, Zambia and Zimbabwe; (2) clinical data from children, adolescents and young adults with HIV aged ≤14 years from the Western Cape (WC) in South Africa. Outcomes of patients lost to follow-up were available from (1) a tracing study and (2) linkage to a health information exchange.

COVID-19 Vaccine Uptake and Effectiveness by Time since Vaccination in the Western Cape Province, South Africa: An Observational Cohort Study during 2020-2022.

There are few data on the real-world effectiveness of COVID-19 vaccines and boosting in Africa, which experienced widespread SARS-CoV-2 infection before vaccine availability. We assessed the association between vaccination and severe COVID-19 in the Western Cape, South Africa, in an observational cohort study of >2 million adults during 2020-2022. We described SARS-CoV-2 testing, COVID-19 outcomes, and vaccine uptake over time.

The cyclical cascade of HIV care: Temporal care engagement trends within a population-wide cohort.

Background: The traditional HIV treatment cascade aims to visualise the journey of each person living with HIV from diagnosis, through initiation on antiretroviral therapy (ART) to treatment success, represented by virological suppression. This representation has been a pivotal tool in highlighting and quantifying sequential gaps along the care continuum. There is longstanding recognition, however, that this may oversimplify the complexity of real-world engagement with HIV services in settings with mature high-burden HIV epidemics.

Virologic outcomes with tenofovir-lamivudine-dolutegravir in adults failing PI-based second-line ART.

Background: In South African antiretroviral guidelines, selected patients failing second-line protease inhibitor (PI)-based therapy qualify for genotypic resistance testing - those with PI resistance receive darunavir-based third-line regimens; those without PI resistance continue current regimen with adherence support. The Western Cape province, from September 2020, implemented a strategy of tenofovir-lamivudine-dolutegravir (TLD) for patients, provided there was no tenofovir resistance, irrespective of PI resistance.

Objectives: To evaluate virologic outcomes with TLD among adults failing second-line PI regimens with no tenofovir resistance.

Can routine antenatal data be used to assess HIV antiretroviral therapy coverage among pregnant women? Evaluating the validity of different data sources in the Western Cape, South Africa.

Background: Accurate measurement of antenatal antiretroviral treatment (ART) coverage in pregnancy is imperative in tracking progress towards elimination of vertical HIV transmission. In the Western Cape, South Africa, public-sector individual-level routine data are consolidated from multiple sources, enabling the description of temporal changes in population-wide antenatal antiretroviral coverage. We evaluated the validity of different methods for measuring ART coverage among pregnant women.

ART history prior to conception: trends and association with postpartum disengagement from HIV care in Khayelitsha, South Africa (2013-2019): a retrospective cohort study.

Introduction: In recent years, the expansion of HIV treatment eligibility has resulted in an increase in people with antiretroviral therapy (ART) experience prior to pregnancy but little is known about postpartum engagement in care in this population. We examined differences in disengagement from HIV care after delivery by maternal ART history before conception.

Methods: We analysed data from people living with HIV (aged 15-49) in Khayelitsha, South Africa, with ≥1 live birth between April 2013 and March 2019.

Exploring the validity of routine individuated service data for antenatal HIV surveillance in the Western Cape.

Background: In the Western Cape, South Africa, public-sector individual-level routine data are consolidated from multiple sources through the Provincial Health Data Centre (PHDC). This enables the description of temporal changes in population-wide antenatal HIV seroprevalence. We evaluated the validity of these data compared to aggregated program data and population-wide sentinel antenatal HIV seroprevalence surveys for the Western Cape province.

Factors associated with vertical transmission of HIV in the Western Cape, South Africa: a retrospective cohort analysis.

Introduction: Monitoring mother-infant pairs with HIV exposure is needed to assess the effectiveness of vertical transmission (VT) prevention programmes and progress towards VT elimination.

Methods: We used routinely collected data on infants with HIV exposure, born May 2018-April 2021 in the Western Cape, South Africa, with follow-up through mid-2022. We assessed the proportion of infants diagnosed with HIV at birth (≤7 days), 10 weeks (>1 to 14 weeks) and >14 weeks as proxies for intrauterine, intrapartum/early breastfeeding and late breastfeeding transmission, respectively.

Correction: Early mortality in tuberculosis patients initially lost to follow up following diagnosis in provincial hospitals and primary health care facilities in Western Cape, South Africa.

[This corrects the article DOI: 10.1371/journal.pone.

Self-transfers, Hospital Admissions and Mortality Among Children and Adolescents Lost to Follow-up From Antiretroviral Therapy Programs in the Western Cape, South Africa Between 2004 and 2019: Linkage to Provincial Records.

Background: Pediatric programs face a high rate of loss to follow-up (LTFU) among children and adolescents living with HIV (CAHIV). We assessed true outcomes and predictors of these among CAHIV who were LTFU using linkage to the Western Cape Provincial Health Data Centre at Western Cape sites of the International epidemiology Databases to Evaluate AIDS-Southern Africa collaboration.

Methods: We examined factors associated with self-transfer, hospital admission and mortality using competing risks regression in a retrospective cohort of CAHIV initiating antiretroviral therapy <15 years old between 2004 and 2019 and deemed LTFU (no recorded visit at the original facility for ≥180 days from the last visit date before database closure and not known to have officially transferred out or deceased).

COVID-19 vaccine uptake and effectiveness by time since vaccination in the Western Cape province, South Africa: An observational cohort study during 2020-2022.

Background: There are few data on the real-world effectiveness of COVID-19 vaccines and boosting in Africa, which experienced high levels of SARS-CoV-2 infection in a mostly vaccine-naïve population, and has limited vaccine coverage and competing health service priorities. We assessed the association between vaccination and severe COVID-19 in the Western Cape, South Africa.

Methods: We performed an observational cohort study of >2 million adults during 2020-2022.

Translating the consent form is the tip of the iceberg: using cognitive interviews to assess the barriers to informed consent in South African health facilities.

The increasing digitisation of personal health data has led to an increase in the demand for onward health data. This study sought to develop local language scripts for use in public sector maternity clinics to capture informed consent for onward health data use. The script considered five possible health data uses: 1.

Reducing Initial Loss to Follow-up Among People With Bacteriologically Confirmed Tuberculosis: LINKEDin, a Quasi-experimental Study in South Africa.

Every person diagnosed with tuberculosis (TB) needs to initiate treatment. The World Health Organization estimated that 61% of people who developed TB in 2021 were included in a TB treatment registration system. Initial loss to follow-up (ILTFU) is the loss of persons to care between diagnosis and treatment initiation/registration.

Change in HIV-related characteristics of children hospitalised with infectious diseases in Western Cape, South Africa, 2008-2021: a time trend analysis.

Introduction: With the scaling up of vertical HIV transmission prevention programmes, the HIV-related population profile of children in South Africa has shifted. We described temporal changes in HIV-related characteristics of children, aged ≤3 years (up to the third birthday), with infectious disease hospitalisations across the Western Cape province.

Methods: We used routinely collected electronic data to identify children born in the Western Cape with infectious disease hospital records for lower respiratory tract infections, diarrhoea, meningitis and tuberculous meningitis, from 2008 to 2021.

Prevention of vertical transmission of HIV in Khayelitsha, South Africa: A contemporary review of services after 20 years.

Background: The first vertical transmission of HIV prevention (VTP) programme in South Africa was launched in 1999 in Khayelitsha, Western Cape Province (WC). Since then, VTP guidelines have expanded in complexity and scope.

Objectives: To describe contemporary VTP uptake in Khayelitsha and quantify vertical transmission (VT) risk factors based on linked routine electronic health data.

Maternal weight trajectories and associations with infant growth in South African women.

Background: Despite the close relationship between pre-pregnancy body mass index (BMI), gestational weight gain (GWG) and postpartum weight (PPW), these factors are often studied separately. There are no data characterising longitudinal weight trajectories among pregnant and postpartum women in urban African populations. We examined maternal weight trajectories from pregnancy through to 12 months postpartum, factors associated with higher weight trajectory class membership and associations of weight trajectories with infant growth at 12 months.

Maternal and birth outcomes in pregnant people with and without HIV in the Western Cape, South Africa.

Introduction: We evaluated associations of HIV and antiretroviral therapy (ART) with birth and maternal outcomes at a province-wide-level in the Western Cape, South Africa, in a recent cohort before dolutegravir-based first-line ART implementation.

Methods: This retrospective cohort study included pregnant people delivering in 2018-2019 with data in the Western Cape Provincial Health Data Centre which integrates individual-level data on all public sector patients from multiple electronic platforms using unique identifiers. Adverse birth outcomes (stillbirth, low birth weight (LBW), very LBW (VLBW)) and maternal outcomes (early and late pregnancy-related deaths, early and late hospitalizations) were compared by HIV/ART status and adjusted prevalence ratios (aPRs) calculated using log-binomial regression.