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Prevalence of SARS-CoV-2 in Children Identified by Preprocedural Testing at 5 US Children's Hospital Systems
Anna F Wang-Erickson1,2,3, Xueyan Zhang3, Klancie Dauer3
1From the Department of Pediatrics, Division of Infectious Diseases, University of Pittsburgh School of Medicine, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA.
Insights
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) prevalence was low in asymptomatic children tested before medical procedures. This suggests children played a minor role in early pandemic transmission before widespread vaccination.
Area of Science:
- Pediatric Infectious Diseases
- Epidemiology
- Public Health Policy
Background:
- Initial assumptions of high SARS-CoV-2 burden in asymptomatic children influenced early pandemic policies.
- Universal preprocedural testing for SARS-CoV-2 was implemented in some hospitals prior to vaccine availability.
- Understanding prevalence in children is crucial for informing future pandemic responses.
Purpose of the Study:
- To determine the prevalence of SARS-CoV-2 in outpatient children undergoing preprocedural testing.
- To identify factors associated with SARS-CoV-2 infection in this pediatric population.
- To inform public health and hospital policies regarding children and viral transmission.
Main Methods:
- Retrospective analysis of preprocedural SARS-CoV-2 polymerase chain reaction test results from 5 US hospital systems (March 2020 - February 2021).
- Data included 74,382 pediatric patients undergoing 93,760 tests.
- Mixed logistic regression was used to calculate adjusted odds ratios (AORs) for associated factors.
Main Results:
- Overall SARS-CoV-2 prevalence was 3.1% (2889 positive tests) among 74,382 pediatric patients.
- Prevalence varied significantly across different hospital sites.
- Factors associated with higher infection risk included lack of insurance, public insurance, Hispanic ethnicity, Black race, and school-aged/adolescent children.
Conclusions:
- SARS-CoV-2 prevalence was low in predominantly asymptomatic outpatient children tested preprocedurally.
- Undetected childhood infections likely had a limited role in early SARS-CoV-2 transmission during the naive prevaccine pandemic period.
- Findings challenge initial assumptions and support evidence-based policy adjustments for future pandemics.
Background:
The burden of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in asymptomatic children was initially presumed to be high, which influenced hospital, school and childcare policies. Before vaccines were widely available, some hospitals implemented universal preprocedural SARS-CoV-2 polymerase chain reaction testing on asymptomatic patients. Understanding SARS-CoV-2 prevalence in asymptomatic children is needed to illuminate the diversity of viral characteristics and inform policies implemented during future pandemics.
Methods:
Data were extracted from patient records of outpatient children who were preprocedurally tested for SARS-CoV-2 from 5 US hospital systems between March 1, 2020, and February 28, 2021. Prevalence was determined from positive test results. Adjusted odds ratios (AORs) were calculated using mixed logistic regression with the site as a random effect.
Results:
This study analyzed 93,760 preprocedural SARS-CoV-2 test results from 74,382 patients and found 2693 infections (3.6%) from 2889 positive tests (3.1%). Site-specific prevalence varied across sites. Factors modestly associated with infection included being uninsured [AOR, 1.76 (95% confidence interval [CI], 1.45-2.13)], publicly insured [AOR, 1.17 (95% CI, 1.05-1.30)], Hispanic [AOR, 1.78 (95% CI, 1.59-1.99)], Black [AOR, 1.22 (95% CI, 1.06-1.39)], elementary school age [5-11 years; AOR, 1.15 (95% CI, 1.03-1.28)], or adolescent [12-17 years; AOR, 1.26 (95% CI, 1.13-1.41)].
Conclusions:
SARS-CoV-2 prevalence was low in outpatient children undergoing preprocedural testing, a population that was predominantly asymptomatic at the time of testing. This study contributes evidence that suggests that undetected infection in children likely did not play a predominant role in SARS-CoV-2 transmission during the early prevaccine pandemic period when the general population was naive to the virus.
