IntroductionEstimating COVID-19 cumulative incidence in Africa remains problematic due to challenges in contact tracing, routine surveillance systems and laboratory testing capacities and strategies. We undertook a meta-analysis of population-based seroprevalence studies to estimate SARS-CoV-2 seroprevalence in Africa to inform evidence-based decision making on public health and social measures (PHSM) and vaccine strategy.MethodsWe searched for seroprevalence studies conducted in Africa published 1 January 2020–30 December 2021 in Medline, Embase, Web of Science and Europe PMC (preprints), grey literature, media releases and early results from WHO Unity studies. All studies were screened, extracted, assessed for risk of bias and evaluated for alignment with the WHO Unity seroprevalence protocol. We conducted descriptive analyses of seroprevalence and meta-analysed seroprevalence differences by demographic groups, place and time. We estimated the extent of undetected infections by comparing seroprevalence and cumulative incidence of confirmed cases reported to WHO.PROSPERO: CRD42020183634.ResultsWe identified 56 full texts or early results, reporting 153 distinct seroprevalence studies in Africa. Of these, 97 (63%) were low/moderate risk of bias studies. SARS-CoV-2 seroprevalence rose from 3.0% (95% CI 1.0% to 9.2%) in April–June 2020 to 65.1% (95% CI 56.3% to 73.0%) in July–September 2021. The ratios of seroprevalence from infection to cumulative incidence of confirmed cases was large (overall: 100:1, ranging from 18:1 to 954:1) and steady over time. Seroprevalence was highly heterogeneous both within countries—urban versus rural (lower seroprevalence for rural geographic areas), children versus adults (children aged 0–9 years had the lowest seroprevalence)—and between countries and African subregions.ConclusionWe report high seroprevalence in Africa suggesting greater population exposure to SARS-CoV-2 and potential protection against COVID-19 severe disease than indicated by surveillance data. As seroprevalence was heterogeneous, targeted PHSM and vaccination strategies need to be tailored to local epidemiological situations.

IntroductionEstimating COVID-19 cumulative incidence in Africa remains problematic due to challenges in contact tracing, routine surveillance systems and laboratory testing capacities and strategies. We undertook a meta-analysis of population-based seroprevalence studies to estimate SARS-CoV-2 seroprevalence in Africa to inform evidence-based decision making on Public Health and Social Measures (PHSM) and vaccine strategy.MethodsWe searched for seroprevalence studies conducted in Africa published 01-01-2020 to 30-12-2021 in Medline, Embase, Web of Science, and Europe PMC (preprints), grey literature, media releases and early results from WHO Unity studies. All studies were screened, extracted, assessed for risk of bias and evaluated for alignment with the WHO Unity protocol for seroepidemiological investigations. We conducted descriptive analyses of seroprevalence and meta-analysed seroprevalence differences by demographic groups, place and time. We estimated the extent of undetected infections by comparing seroprevalence and cumulative incidence of confirmed cases reported to WHO. PROSPERO: CRD42020183634.ResultsWe identified 54 full texts or early results, reporting 151 distinct seroprevalence studies in Africa Of these, 95 (63%) were low/moderate risk of bias studies. SARS-CoV-2 seroprevalence rose from 3.0% [95% CI: 1.0-9.2%] in Q2 2020 to 65.1% [95% CI: 56.3-73.0%] in Q3 2021. The ratios of seroprevalence from infection to cumulative incidence of confirmed cases was large (overall: 97:1, ranging from 10:1 to 958:1) and steady over time. Seroprevalence was highly heterogeneous both within countries - urban vs. rural (lower seroprevalence for rural geographic areas), children vs. adults (children aged 0-9 years had the lowest seroprevalence) - and between countries and African sub-regions (Middle, Western and Eastern Africa associated with higher seroprevalence).ConclusionWe report high seroprevalence in Africa suggesting greater population exposure to SARS-CoV-2 and protection against COVID-19 disease than indicated by surveillance data. As seroprevalence was heterogeneous, targeted PHSM and vaccination strategies need to be tailored to local epidemiological situations.

BackgroundConducting risk of bias assessments for seroprevalence studies is a crucial component of infection surveillance but can be a time-consuming and subjective process. We aimed to develop and evaluate decision rules for transparent and reproducible risk of bias assessments of seroprevalence studies.MethodsWe developed the SeroTracker-ROB decision rules, which generate risk of bias assessments for seroprevalence studies from an adapted version of the Joanna Briggs Institute Critical Appraisal Checklist for Prevalence Studies. The decision rules were developed using published guidance on risk of bias assessment for prevalence studies, and the consensus opinions of researchers that have critically appraised thousands of prevalence studies. The decision rules were evaluated against SeroTracker’s living systematic review database of SARS-CoV-2 seroprevalence studies. We determined decision rule coverage by calculating the proportion of database studies for which SeroTracker-ROB yielded a risk of bias assessment, and reliability by calculating intraclass correlations between SeroTracker-RoB assessments and the consensus manual judgements of two independent reviewers.ResultsThe SeroTracker-ROB decision rules for risk of bias assessment classified 100% (n = 2,070) of prevalence studies in SeroTracker’s database and showed good reliability compared to manual review (intraclass correlation 0.77, 95% CI 0.74 to 0.80). We developed a tool that implements these decision rules for use by other researchers.ConclusionsThe SeroTracker-ROB decision rules enabled rapid, transparent, and reproducible risk of bias assessment of seroprevalence studies, and may serve to support infection surveillance.

To describe the reasoning processes used by pediatric intensivists to make antibiotic-related decisions.

CONTEXT: Respiratory virus (RV) detection tests are commonly used in hospitalized children to diagnose viral acute respiratory infection (ARI), but their clinical utility is uncertain. OBJECTIVES: To systematically review and meta-analyze the impact of RV test results on antibiotic consumption, ancillary testing, hospital length of stay, and antiviral use in children hospitalized with severe ARI. DATA SOURCES: Seven medical literature databases from 1985 through January 2018 were analyzed. STUDY SELECTION: Studies in children ,18 years old hospitalized for severe ARI in which the clinical impact of a positive versus negative RV test result or RV testing versus no testing are compared. DATA EXTRACTION: Two reviewers independently screened titles, abstracts, and full texts; extracted data; and assessed study quality. RESULTS: We included 23 studies. High heterogeneity did not permit an overall meta-analysis. Subgroup analyses by age, RV test type, and viral target showed no difference in the proportion of patients receiving antibiotics between those with positive versus negative test results. Stratification by study design revealed that RV testing decreased antibiotic use in prospective cohort studies (odds ratio 5 0.58; 95% confidence interval: 0.45-0.75). Pooled results revealed no conclusive impact on chest radiograph use (odds ratio 5 0.71; 95% confidence interval: 0.48-1.04). Results of most studies found that positive RV test results did not impact median hospital length of stay, but they may decrease antibiotic duration. Nineteen (83%) studies were at serious risk of bias. LIMITATIONS: Low-quality studies and high clinical and statistical heterogeneity were among the limitations. CONCLUSIONS: Higher-quality prospective studies are needed to determine the impact of RV testing on antibiotic use in children hospitalized with severe ARI.