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Topics in Antiviral Medicine ; 30(1 SUPPL):18, 2022.
Article in English | EMBASE | ID: covidwho-1880294


Background: The Sisonke Phase IIIB open-label implementation study vaccinated health care workers (HCWs) with the single dose Ad26.COV2.S vaccine during two phases of the South African Covid-19 epidemic, dominated first by the Beta followed by the Delta variant of concern. Methods: HCWs were vaccinated over 3 months (17 February-17 May 2021). Safety was monitored by self-reporting, facility reporting and linkage to national databases. Vaccine effectiveness (VE) against Covid-19 related hospitalisation, hospitalisation requiring critical or intensive care and death, ascertained 28 days or more post vaccination was assessed up until 17 July 2021. Nested sub-cohorts (A and B) from two national medical schemes were evaluated to assess VE using a matched retrospective cohort design. Results: Over the 3-month period, 477234 HCWs were vaccinated in 122 vaccination sites across South Africa. VE derived from the sub-cohorts comprising 215 813 HCWs was 83% (95% CI 75-89) to prevent Covid-19 deaths, 75% (95% CI 69-82) to prevent hospital admissions requiring critical or intensive care and 67% (95% CI 62-71) to prevent Covid-19 related hospitalisations. The VE was maintained in older HCWs and those with comorbidities including HIV infection. VE remained consistent throughout the Beta and Delta dominant phases of the study. 10279 adverse events were reported and 139 (1.4%) were serious, including two cases of thrombosis with thrombocytopenia syndrome and four cases of Guillain-Barré syndrome who recovered. Conclusion: The single dose Ad26.COV2.S was safe and effective against severe Covid-19 disease and death post-vaccination, and against both Beta and Delta variants providing real-world evidence for its use globally.

Topics in Antiviral Medicine ; 30(1 SUPPL):37-38, 2022.
Article in English | EMBASE | ID: covidwho-1880239


Background: Post-Acute Sequelae of SARS-CoV-2 (PASC) is characterized by persistent symptoms negatively impacting quality of life several weeks after SARS-CoV-2 diagnosis. Proposed risk factors include older age, female sex, comorbidities, and severe COVID-19, including hospitalization and oxygen requirement. Yet, associations of these factors with prolonged symptoms remain poorly understood globally. Methods: The global, observational cohort study HVTN 405/HPTN 1901 characterizes the clinical and immunologic course in the first year after SARS-CoV-2 infection among adults. The cohort was categorized by infection severity (asymptomatic;symptomatic with no oxygen requirement [NOR];non-invasive oxygen requirement [NIOR];or invasive oxygen requirement [IOR]). A regression model was applied to estimate geometric mean ratios (GMR) for duration and odds ratios (OR) for persistence of symptoms. Results: 759 participants from Peru (25.2%), USA (26.0%), Republic of South Africa (RSA, 37.7%), and non-RSA Sub-Saharan Africa (11.2%) were enrolled a median of 51 (IQR 35-66) days post-diagnosis, from May 2020 to Mar 2021. 53.8% were female, 69.8% were <55yo (median 44yo, IQR 33-58) and identified as non-Hispanic Black (42.7%), Hispanic (27.9%) or non-Hispanic White (15.8%). Comorbidities included obesity (42.8%), hypertension (24%), diabetes (14%), HIV infection (11.6%) and lung disease (7.5%). 76.2% were symptomatic (NOR 47.4%;NIOR 22.9%;and IOR 5.8%). Among symptomatic participants, median acute COVID-19 duration was 20 days (IQR 11-35);43.3% had ≥1 persistent symptom after COVID-19 resolution (39.8% NOR;49.1 % NIOR+IOR;p=0.037);16.8% reported ≥1 symptom >42 days (14.0% NOR;21.6% NIOR+IOR;p=0.025). Symptom duration was not associated with age or sex assigned at birth but was associated with disease severity (GMR 2.09;95%CI 1.5-2.91, p<0.001 for NIOR vs NOR;not significant for IOR vs NIOR), lung disease (GMR 2.43;95%CI 1.42-4.16, p=0.001), and global region (p<0.05, see Figure 1). Prolonged viral shedding was associated with persistent diarrhea (OR 6.59;95%CI 1.65-26.86;p=0.008). Conclusion: A recovery course consistent with PASC was significantly associated with infection severity, lung disease, and region. Regional differences in symptom profiles and duration may be influenced by viral diversity, genetic, or cultural factors and likely reflect disparities in healthcare access and interventions. Better understanding PASC associations may improve clinical assessment and management globally.

Preprint in English | EMBASE | ID: ppcovidwho-327037


Following the results of the ENSEMBLE 2 study, which demonstrated improved vaccine efficacy of a two-dose regimen of Ad26.COV.2 vaccine given 2 months apart, we expanded the Sisonke study which had provided single dose Ad26.COV.2 vaccine to almost 500 000 health care workers (HCW) in South Africa to include a booster dose of the Ad26.COV.2. Sisonke 2 enrolled 227 310 HCW from the 8 November to the 17 December 2021. Enrolment commenced before the onset of the Omicron driven fourth wave in South Africa affording us an opportunity to evaluate early VE in preventing hospital admissions of a homologous boost of the Ad26.COV.2 vaccine given 6-9 months after the initial vaccination in HCW. We estimated vaccine effectiveness (VE) of the Ad26.COV2.S vaccine booster in 69 092 HCW as compared to unvaccinated individuals enrolled in the same managed care organization using a test negative design. We compared VE against COVID19 admission for omicron during the period 15 November to 20 December 2021. After adjusting for confounders, we observed that VE for hospitalisation increased over time since booster dose, from 63% (95%CI 31-81%);to 84% (95% CI 67-92%) and then 85% (95% CI: 54-95%), 0-13 days, 14-27 days, and 1-2 months post-boost. We provide the first evidence of the effectiveness of a homologous Ad26.COV.2 vaccine boost given 6-9 months after the initial single vaccination series during a period of omicron variant circulation. This data is important given the increased reliance on the Ad26.COV.2 vaccine in Africa.

Preprint in English | EMBASE | ID: ppcovidwho-326920


Background: The Sisonke open-label phase 3b implementation study aimed to assess the safety and effectiveness of the Janssen Ad26.CoV2.S vaccine among health care workers (HCWs) in South Africa. Here, we present the safety data. Methods: We monitored adverse events (AEs) at vaccination sites, through self-reporting triggered by text messages after vaccination, health care provider reports and by active case finding. The frequency and incidence rate of non-serious and serious AEs were evaluated from day of first vaccination (17 February 2021) until 28 days after the final vaccination (15 June 2021). COVID-19 breakthrough infections, hospitalisations and deaths were ascertained via linkage of the electronic vaccination register with existing national databases. Findings: Of 477,234 participants, 10,279 (2.2%) reported AEs, of which 139 (1.4%) were serious. Women reported more AEs than men (2.3% vs. 1.6%). AE reports decreased with increasing age (3.2% for 18–30, 2.1% for 31-45, 1.8% for 46-55 and 1.5% in >55-year-olds). Participants with previous COVID-19 infection reported slightly more AEs (2.6% vs. 2.1%). The commonest reactogenicity events were headache and body aches, followed by injection site pain and fever, and most occurred within 48 hours of vaccination. Two cases of Thrombosis with Thrombocytopenia Syndrome and four cases of Guillain-Barre Syndrome were reported post-vaccination. Serious AEs and AEs of special interest including vascular and nervous system events, immune system disorders and deaths occurred at lower than the expected population rates. Interpretation: The single-dose Ad26.CoV2.S vaccine had an acceptable safety profile supporting the continued use of this vaccine in our setting.