SARS-CoV-2 Seroprevalence Compared with Confirmed COVID-19 Cases among Children, Colorado, USA, May–July 2021

Abstract

To compare SARS-CoV-2 antibody seroprevalence among children with seropositive confirmed COVID-19 case counts (case ascertainment by molecular amplification) in Colorado, USA, we conducted a cross-sectional serosurvey during May–July 2021. For a convenience sample of 829 Colorado children, SARS-CoV-2 seroprevalence was 36.7%, compared with prevalence of 6.5% according to individually matched COVID-19 test results reported to public health. Compared with non-Hispanic White children, seroprevalence was higher among Hispanic, non-Hispanic Black, and non-Hispanic other race children, and case ascertainment was significantly lower among Hispanic and non-Hispanic Black children. This serosurvey accurately estimated SARS-CoV-2 prevalence among children compared with confirmed COVID-19 case counts and revealed substantial racial/ethnic disparities in infections and case ascertainment. Continued efforts to address racial and ethnic differences in disease burden and to overcome potential barriers to case ascertainment, including access to testing, may help mitigate these ongoing disparities.

Pediatric SARS-CoV-2 Seroprevalence, Oregon, USA, November 1, 2020–June 30, 2022

“…We estimated 1.7–2.8 times the number of infections in children from seroprevalence than the reported cumulative incidence in Oregon ( Figure ). This total is a lower degree of underascertainment than had been reported in seroprevalence studies of children during May–July 2021 in the United States ( 1 ).…”

“…However, understanding the true burden of pediatric COVID-19 infection poses a challenge. Children are more likely to have asymptomatic or mild disease, and pediatric infections are, therefore, less likely to be reported to public health authorities ( 1 , 2 ). Clarifying pediatric SARS-CoV-2 prevalence is important because it is well established that children can transmit SARS-CoV-2 to other children and adults ( 3 , 4 ).…”

Routine Surveillance of SARS-CoV-2 Serostatus in Pediatrics Allows Monitoring of Humoral Response

“…The scale of affected individuals may be considerable, with the World Health Organization reporting over 750 million confirmed infections worldwide and nearly 7 million deaths [4]. Seroprevalence data further suggest that the actual numbers could be considerably higher, particularly among the pediatric population [5][6][7]. Through the utilization of routine laboratory blood samples for SARS-CoV-2 prevalence monitoring, we previously demonstrated that the true number of infections may be 3.93-5.66 times higher [8].…”