Children and young women in eastern and southern Africa are key to meeting 2030 HIV targets: time to accelerate action.

New HIV infections and AIDS-related deaths among children and adolescent girls and young women (aged 15-24 years) in eastern and southern Africa continue to occur at unacceptably high rates. The COVID-19 pandemic has also severely undermined ongoing initiatives for HIV prevention and treatment, threatening to set the region back further in its efforts to end AIDS by 2030. Major impediments exist to attaining the UNAIDS 2025 targets among children, adolescent girls, young women, young mothers living with HIV, and young female sex workers residing in eastern and southern Africa. Each population has specific but overlapping needs with regard to diagnosis and linkage to and retention in care. Urgent action is needed to intensify and improve programmes for HIV prevention and treatment, including sexual and reproductive health services for adolescent girls and young women, HIV-positive young mothers, and young female sex workers.

Vascular thrombosis after single dose Ad26.COV2.S vaccine in healthcare workers in South Africa: open label, single arm, phase 3B study (Sisonke study).

Objective: To assess the rates of vascular thrombotic adverse events in the first 35 days after one dose of the Ad26.COV2.S vaccine (Janssen/Johnson & Johnson) in healthcare workers in South Africa and to compare these rates with those observed in the general population. Design: Open label, single arm, phase 3B study. Setting: Sisonke study, South Africa, 17 February to 15 June 2021. Participants: The Sisonke cohort of 477 234 healthcare workers, aged ≥18 years, who received one dose of the Ad26.COV2.S vaccine. Main outcome measures: Observed rates of venous arterial thromboembolism and vaccine induced immune thrombocytopenia and thrombosis in individuals who were vaccinated, compared with expected rates, based on age and sex specific background rates from the Clinical Practice Research Datalink GOLD database (database of longitudinal routinely collected electronic health records from UK primary care practices using Vision general practice patient management software). Results: Most of the study participants were women (74.9%) and median age was 42 years (interquartile range 33-51). Twenty nine (30.6 per 100 000 person years, 95% confidence interval 20.5 to 44.0) vascular thrombotic events occurred at a median of 14 days (7-29) after vaccination. Of these 29 participants, 93.1% were women, median age 46 (37-55) years, and 51.7% had comorbidities. The observed to expected ratios for cerebral venous sinus thrombosis with thrombocytopenia and pulmonary embolism with thrombocytopenia were 10.6 (95% confidence interval 0.3 to 58.8) and 1.2 (0.1 to 6.5), respectively. Because of the small number of adverse events and wide confidence intervals, no conclusions were drawn between these estimates and the expected incidence rates in the population. Conclusions: Vaccine induced immune thrombocytopenia and thrombosis after one dose of the Ad26.COV2.S vaccine was found in only a few patients in this South African population of healthcare workers. These findings are reassuring if considered in terms of the beneficial effects of vaccination against covid-19 disease. These data support the continued use of this vaccine, but surveillance is recommended to identify other incidences of venous and arterial thromboembolism and to improve confidence in the data estimates. Trial registration: ClinicalTrials.gov NCT04838795.

Progress in vaccine development for infectious diseases-a Keystone Symposia report.

The COVID-19 pandemic has taught us many things, among the most important of which is that vaccines are one of the cornerstones of public health that help make modern longevity possible. While several different vaccines have been successful at stemming the morbidity and mortality associated with various infectious diseases, many pathogens/diseases remain recalcitrant to the development of effective vaccination. Recent advances in vaccine technology, immunology, structural biology, and other fields may yet yield insight that will address these diseases; they may also help improve societies' preparedness for future pandemics. On June 1-4, 2022, experts in vaccinology from academia, industry, and government convened for the Keystone symposium "Progress in Vaccine Development for Infectious Diseases" to discuss state-of-the-art technologies, recent advancements in understanding vaccine-mediated immunity, and new aspects of antigen design to aid vaccine effectiveness.

Implementation Science for Eliminating HIV Among Adolescents in High-Burden African Countries: Findings and Lessons Learned from the Adolescent HIV Prevention and Treatment Implementation Science Alliance (AHISA).

Eliminating adolescent HIV in high-burden African countries depends on the success of implementing evidence-based interventions to reduce transmission and improve treatment outcomes. The Adolescent HIV Prevention and Treatment Implementation Science Alliance (AHISA) takes a collaborative approach to addressing key challenges and identifying and developing new areas of investigation to advance the adolescent HIV agenda. This special supplement represents the collective learning of the Alliance related to implementation science in the context of the adolescent HIV continuum of care from multiple African countries. Specifically, this series describes the current academic landscape of adolescent HIV and implementation science, such as the methodological use and utility of implementation measures and frameworks; addresses timely topics such as the use of innovative technologies for study adaptations in the context of the global COVID-19 pandemic; and explores opportunities to enhance adolescent-responsive approaches to HIV prevention and treatment using implementation science.

Association between regular physical activity and the protective effect of vaccination against SARS-CoV-2 in a South African case-control study.

BACKGROUND: Both vaccination and physical activity have been shown to independently decrease the likelihood of severe COVID-19 infection. OBJECTIVE: To assess the association between regular physical activity and vaccination against COVID-19 among healthcare workers. METHODS: A test negative case-control study design was used to estimate the risk of having an associated COVID-19-related hospital admission, among individuals who were unvaccinated compared with those who were fully vaccinated with Ad26.COV2.S (>28 days after a single dose). 196 444 participant tests were stratified into three measured physical activity subgroups with low, moderate and high activity, to test the hypothesis that physical activity is an effect modifier on the relationship between vaccination and hospitalisation. RESULTS: Vaccine effectiveness against a COVID-19-related admission among vaccinated individuals within the low activity group was 60.0% (95% CI 39.0 to 73.8), 72.1% (95% CI 55.2 to 82.6) for the moderate activity group, and 85.8% (95% CI 74.1 to 92.2) for the high activity group. Compared with individuals with low activity levels, vaccinated individuals with moderate and high activity levels had a 1.4 (95% CI 1.36 to 1.51) and 2.8 (95% CI 2.35 to 3.35) times lower risk of COVID-19 admission, respectively (p value <0.001 for both groups). CONCLUSIONS: Regular physical activity was associated with improved vaccine effectiveness against COVID-19 hospitalisation, with higher levels of physical activity associated with greater vaccine effectiveness. Physical activity enhances vaccine effectiveness against severe COVID-19 outcomes and should be encouraged by greater public health messaging.

Novavax NVX-COV2373 triggers neutralization of Omicron sub-lineages.

The SARS-CoV-2 Omicron (B.1.1.529) Variant of Concern (VOC) and its sub-lineages (including BA.2, BA.4, BA.5, BA.2.12.1) contain spike mutations that confer high level resistance to neutralizing antibodies induced by vaccination with ancestral spike or infection with previously circulating variants. The NVX-CoV2373 vaccine, a protein nanoparticle vaccine containing the ancestral spike sequence, has value in countries with constrained cold-chain requirements. Here we report neutralizing titers following two or three doses of NVX-CoV2373. We show that after two doses, Omicron sub-lineages BA.1 and BA.4/BA.5 were resistant to neutralization by 72% (21/29) and 59% (17/29) of samples respectively. However, after a third dose of NVX-CoV2373, we observed high titers against Omicron BA.1 (GMT: 1,197) and BA.4/BA.5 (GMT: 582), with responses similar in magnitude to those triggered by three doses of an mRNA vaccine. These data are of particular relevance as BA.4/BA.5 is dominating in multiple locations, and highlight the potential utility of the NVX-CoV2373 vaccine as a booster in resource-limited environments.

Impact of SARS-CoV-2 exposure history on the T cell and IgG response.

Multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exposures, from infection or vaccination, can potently boost spike antibody responses. Less is known about the impact of repeated exposures on T cell responses. Here, we compare the prevalence and frequency of peripheral SARS-CoV-2-specific T cell and immunoglobulin G (IgG) responses in 190 individuals with complex SARS-CoV-2 exposure histories. As expected, an increasing number of SARS-CoV-2 spike exposures significantly enhances the magnitude of IgG responses, while repeated exposures improve the number of T cell responders but have less impact on SARS-CoV-2 spike-specific T cell frequencies in the circulation. Moreover, we find that the number and nature of exposures (rather than the order of infection and vaccination) shape the spike immune response, with spike-specific CD4 T cells displaying a greater polyfunctional potential following hybrid immunity compared with vaccination only. Characterizing adaptive immunity from an evolving viral and immunological landscape may inform vaccine strategies to elicit optimal immunity as the pandemic progress.

Khuluma: Using Participatory, Peer-Led and Digital Methods to Deliver Psychosocial Support to Young People Living With HIV in South Africa.

Khuluma is a psychosocial and peer-to-peer mHealth intervention that uses text messaging to facilitate support groups for adolescents living with HIV (ALWH) with the aim of contributing toward positive health outcomes. Although use of mobile technology in the form of mHealth interventions has proliferated recently in the field of health, published literature describing methods and processes of its application are limited. We present a set of methods and processes utilised to develop and pilot the Khuluma mHealth intervention amongst young people (15-20 years) in South Africa. We recruited and enrolled 52 adolescents (15-20-year olds) from four clinics in Pretoria and Cape Town to participate in a 6-month pilot of Khuluma. Participants were ALWH, aware of their status, on antiretroviral therapy for more than 12 months, and not suffering from severe depression. We conducted four pre and post intervention focus group discussions (FGDs) with a proportion of ALWH (n = 36) enrolled in the pilot study using participatory methods. Several processes were utilised to then implement this pilot study. These included engaging ALWH for minor study implementation modifications; forming virtual groups; activating the mHealth platform; facilitating and delivering the Khuluma intervention. The acceptability of the intervention was informed by follow-up focus group discussions and text message data. The initial participatory processes helped to tailor the intervention design to participants' needs. The peer-led facilitation of the groups allowed for the provision of sensitive psychosocial support that allowed young people to express themselves freely, develop a sense of self-worth, and interact more. The nature of the mobile technology also allowed participants to build friendships beyond their geographic area and interact with their peers in real time. Within the evolving context of COVID-19, establishing evidence-based processes and methods for intervention design and curation in virtual spaces is critical.

Immunogenicity of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection and Ad26.CoV2.S Vaccination in People Living With Human Immunodeficiency Virus (HIV).

BACKGROUND: People living with HIV (PLWH) have been reported to have a higher risk of more severe COVID-19 disease and death. We assessed the ability of the Ad26.CoV2.S vaccine to elicit neutralizing activity against the Delta variant in PLWH relative to HIV-negative individuals. We also examined effects of HIV status and suppression on Delta neutralization response in SARS-CoV-2-infected unvaccinated participants. METHODS: We enrolled participants who were vaccinated through the SISONKE South African clinical trial of the Ad26.CoV2.S vaccine in healthcare workers (HCWs). PLWH in this group had well-controlled HIV infection. We also enrolled unvaccinated participants previously infected with SARS-CoV-2. Neutralization capacity was assessed by a live virus neutralization assay of the Delta variant. RESULTS: Most Ad26.CoV2.S vaccinated HCWs were previously infected with SARS-CoV-2. In this group, Delta variant neutralization was 9-fold higher compared with the infected-only group and 26-fold higher relative to the vaccinated-only group. No decrease in Delta variant neutralization was observed in PLWH relative to HIV-negative participants. In contrast, SARS-CoV-2-infected, unvaccinated PLWH showed 7-fold lower neutralization and a higher frequency of nonresponders, with the highest frequency of nonresponders in people with HIV viremia. Vaccinated-only participants showed low neutralization capacity. CONCLUSIONS: The neutralization response of the Delta variant following Ad26.CoV2.S vaccination in PLWH with well-controlled HIV was not inferior to HIV-negative participants, irrespective of past SARS-CoV-2 infection. In SARS-CoV-2-infected and nonvaccinated participants, HIV infection reduced the neutralization response to SARS-CoV-2, with the strongest reduction in HIV viremic individuals.

Acceptability and feasibility of leveraging community-based HIV counselling and testing platforms for same-day oral PrEP initiation among adolescent girls and young women in Eastern Cape, South Africa.

INTRODUCTION: Community-based delivery of HIV pre-exposure prophylaxis (PrEP) to South African adolescent girls and young women's (AGYW) could increase access but needs evaluation. We integrated PrEP services via home-based services and pop-up tents into existing community-based HIV testing services (CB-HTS) in Eastern Cape Province, South Africa. METHODS: After accessing CB-HTS via a "pop-up" tent or home-based services, HIV-negative AGYW aged 16-25 years were invited to complete a baseline questionnaire and referred for PrEP services at a community-based PrEP site co-located with pop-up HTS tents. A 30-day supply of PrEP was dispensed. PrEP uptake, time-to-initiation, cohort characteristics and first medication refill within 90 days were measured using descriptive statistics. RESULTS: Of the 1164 AGYW who tested for HIV, 825 (74.3%) completed a questionnaire and 806 (97.7%) were referred for community-based PrEP. Of those, 624 (77.4%) presented for PrEP (482/483 [99.8%] from pop-up HTS and 142/323 [44.0%] from home-based HTS), of which 603 (96.6%) initiated PrEP. Of those initiating PrEP following home-based HTS, 59.1% initiated within 0-3 days, 25.6% within 4-14 days and 15.3% took ≥15 days to initiate; 100% of AGYW who used pop-up HTS initiated PrEP the same day. Among AGWY initiating PrEP, 37.5% had a detectable sexually transmitted infection (STI). Although AGYW reported a low self-perception of HIV risk, post-hoc application of HIV risk assessment measures to available data classified most study participants as high risk for HIV acquisition. Cumulatively, 329 (54.6%) AGYW presented for a first medication refill within 90 days of accepting their first bottle of PrEP. CONCLUSIONS: Leveraging CB-HTS platforms to provide same-day PrEP initiation and refill services was acceptable to AGYW. A higher proportion of AGYW initiated PrEP when co-located with CB-HTS sites compared to those referred following home-based HTS, suggesting that proximity of CB-HTS and PrEP services facilitates PrEP uptake among AGYW. The high prevalence of STIs among those initiating PrEP necessitates the integration of STI and HIV prevention programs for AGYW. Eligibility for PrEP initiation should not be required among AHYW in high HIV burden communities. Community-based service delivery will be crucial to maintaining access to PrEP services during the COVID-19 pandemic and future health and humanitarian emergencies.

Women of Worth: the impact of a cash plus intervention to enhance attendance and reduce sexual health risks for young women in Cape Town, South Africa.

INTRODUCTION: Conditional cash transfers (CTs) augmented with other interventions are promising interventions for reducing HIV risk in adolescent girls and young women. METHODS: A multi-phase, quasi-experimental study assessed the impact of a CT (ZAR300; $22) conditional on attending a skills building intervention, Women of Worth (WoW), designed to improve sexual and reproductive health (SRH) outcomes in Cape Town, South Africa from May 2017 to December 2019. The intervention entailed 12 sessions with encouragement to attend adolescent and youth-friendly health services. Women aged 19-24 years were randomized 1:1 to receive the intervention with a CT ("cash + care" or C+C) or without a CT ("care"). The study included a pilot phase followed by a post-modification phase with improved uptake and retention without changing programme content or CT. Self-reported HIV prevalence and SRH/HIV vulnerability were assessed via a self-administered questionnaire at baseline, after 11 sessions, and 6-30 months' post-intervention for a subset. Mixed effect logistic regression models were fitted to estimate within-subject changes in outcomes. RESULTS: Of 5116 participants, 904 (452 participants per arm) were in the pilot and 4212 (2039 "care" participants and 2173 "C+C" participants) were in the post modified phase. There were 1867 (85.9%) and 135 (6,6%) participants in the "C+C" group and the "Care," respectively, that were WoW completers (≥ 11 sessions/retention). During the pilot phase, 194 (42.9%) and 18 (4.0%) participants in "C+C" and the "care" groups were retained. Receiving a CT sustained participation nearly 60-fold (OR 60.37; 95% CI: 17.32; 210.50, p <0.001). Three-hundred and thirty women were followed for a median of 15.0 months [IQR: 13.3; 17.8] to assess the durability of impact. Self-reported new employment status increased more than three-fold (p <0.001) at WoW completion and was sustained to the longer time point. Intimate partner violence indicators were reduced immediately after WoW, but this was not durable. CONCLUSIONS: Participants receiving CT had sustained participation in an SRH/HIV prevention skills building with improvement in employment and some SRH outcomes. Layered, "young woman centred" programmes to address HIV and SRH risk in young women may be enhanced with CT.

Ad26.COV2.S breakthrough infections induce high titers of neutralizing antibodies against Omicron and other SARS-CoV-2 variants of concern.

The Janssen (Johnson & Johnson) Ad26.COV2.S non-replicating viral vector vaccine has been widely deployed for COVID-19 vaccination programs in resource-limited settings. Here we confirm that neutralizing and binding antibody responses to Ad26.COV2.S vaccination are stable for 6 months post-vaccination, when tested against multiple SARS-CoV-2 variants. Secondly, using longitudinal samples from individuals who experienced clinically mild breakthrough infections 4 to 5 months after vaccination, we show dramatically boosted binding antibodies, Fc effector function, and neutralization. These high titer responses are of similar magnitude to humoral immune responses measured in convalescent donors who had been hospitalized with severe illness, and are cross-reactive against diverse SARS-CoV-2 variants, including the neutralization-resistant Omicron (B.1.1.529) variant that currently dominates global infections, as well as SARS-CoV-1. These data have implications for population immunity in areas where the Ad26.COV2.S vaccine has been widely deployed, but where ongoing infections continue to occur at high levels.

Emergence and phenotypic characterization of the global SARS-CoV-2 C.1.2 lineage.

Global genomic surveillance of SARS-CoV-2 has identified variants associated with increased transmissibility, neutralization resistance and disease severity. Here we report the emergence of the PANGO lineage C.1.2, detected at low prevalence in South Africa and eleven other countries. The initial C.1.2 detection is associated with a high substitution rate, and includes changes within the spike protein that have been associated with increased transmissibility or reduced neutralization sensitivity in SARS-CoV-2 variants of concern or variants of interest. Like Beta and Delta, C.1.2 shows significantly reduced neutralization sensitivity to plasma from vaccinees and individuals infected with the ancestral D614G virus. In contrast, convalescent donors infected with either Beta or Delta show high plasma neutralization against C.1.2. These functional data suggest that vaccine efficacy against C.1.2 will be equivalent to Beta and Delta, and that prior infection with either Beta or Delta will likely offer protection against C.1.2.

High Asymptomatic Carriage With the Omicron Variant in South Africa.

We report a 23% asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) Omicron carriage rate in participants being enrolled into a clinical trial in South Africa, 15-fold higher than in trials before Omicron. We also found lower CD4 + T-cell counts in persons with human immunodeficiency virus (HIV) strongly correlated with increased odds of being SARS-CoV-2 polymerase chain reaction (PCR) positive.