Abstract
Background: Antibody responses to virus reflect exposure and potential protection.
Methods: We developed a highly specific and sensitive approach to measuring antibodies against SARS-CoV-2 for population-scale immune surveillance. Antibody positivity was defined as a dual-positive response against both the receptor-binding domain and nucleocapsid proteins of SARS-CoV-2. Antibodies were measured by immunoprecipitation assays in capillary blood from 15,771 children aged 1 to 18 years living in Bavaria, Germany, and participating in a public health type 1 diabetes screening program (ClinicalTrials.gov: NCT04039945 ), in 1,916 dried blood spots from neonates in a Bavarian screening study (ClinicalTrials.gov: NCT03316261 ), and in 75 SARS-CoV-2-positive individuals. Virus positive incidence was obtained from the Bavarian health authority data.
Findings: Dual-antibody positivity was detected in none of the 3,887 children in 2019 (100% specificity) and 73 of 75 SARS-CoV-2-positive individuals (97.3% sensitivity). Antibody surveillance in children during 2020 resulted in frequencies of 0.08% in January to March, 0.61% in April, 0.74% in May, 1.13% in June, and 0.91% in July. Antibody prevalence from April 2020 was 6-fold higher than the incidence of authority-reported cases (156 per 100,000 children), showed marked variation between the seven Bavarian regions (p < 0.0001), and was not associated with age or sex. Transmission in children with virus-positive family members was 35%. 47% of positive children were asymptomatic. No association with type 1 diabetes autoimmunity was observed. Antibody frequency in newborns was 0.47%.
Conclusions: We demonstrate the value of population-based screening programs for pandemic monitoring.
Funding: The work was supported by funding from the BMBF (FKZ01KX1818).
Keywords: RBD; SARS-CoV-2 antibody; nucleocapsid antigen; public health screening; receptor binding domain; seroprevalence; type 1 diabetes.
【저자키워드】 Seroprevalence, Receptor binding domain, type 1 diabetes., SARS-CoV-2 antibody, RBD, nucleocapsid antigen, public health screening, 【초록키워드】 public health, SARS-CoV-2, Type 1 diabetes, Autoimmunity, pandemic, antibody, children, Antibody Response, Seroprevalence, Variation, Sex, diabetes, virus, immune, nucleocapsid protein, Receptor binding domain, Prevalence, sensitivity, specificity, Antibody responses, Newborn, dried blood spot, Neonate, Neonates, Region, Receptor-binding domain, SARS-CoV-2 antibody, Asymptomatic, Surveillance, Germany, nucleocapsid, age, incidence, funding, nucleocapsid antigen, association, Frequency, Receptor binding, family members, health screening, Health authority, screening programs, screening program, immune surveillance, frequencies, Nucleocapsid proteins, immunoprecipitation, positive, capillary blood, SARS-CoV-2-positive individuals, approach, Seven, defined, supported, the receptor-binding domain, were measured, diabete, was obtained, SARS-CoV-2-positive individual, 【제목키워드】 SARS-CoV-2, Screening, exposure, Public, Rate,