Abstract
Background: The immunologic features of children with coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are not clearly delineated. This study was conducted to evaluate SARS-CoV-2-specific antibody responses in children with COVID-19.
Methods: The levels of anti-spike (S) IgG, anti-SARS-CoV-2 IgG, and neutralizing antibody (NAb) were measured during various time points in children <19 years of age with COVID-19 in South Korea from February 2020 to September 2020.
Results: One hundred sixty-five blood samples from 114 children with COVID-19 (43.9% asymptomatic and 56.1% mildly symptomatic) were analyzed. In both asymptomatic and mildly symptomatic children, the positive rates of anti-S IgG, anti-SARS-CoV-2 IgG, and NAb were low within 7 days after onset, but they soon reached 100% 14 to <28 days after onset. In symptomatic children, the geometric mean titers (GMTs) of antibodies were all below the positive cutoff during the first 2 weeks from onset and peaked at 28 to <56 days (5.6 for anti-S IgG, 383.6 for anti-SARS-CoV-2 IgG, and 55.0 for NAb, P < .001, respectively). Antibody levels remained detectable up to 3 months after infection. The antibody GMTs during the period 14 to <56 days after symptom onset were highest in children aged 0-4 years.
Conclusions: These results collectively present the humoral immune responses during SARS-CoV-2 infection in children. A further longitudinal study is needed to thoroughly understand the immune system and for effective vaccine development in children during the COVID-19 pandemic.
Keywords: COVID-19; SARS-CoV-2; antibody response; children.
【저자키워드】 COVID-19, SARS-CoV-2, children, Antibody Response, 【초록키워드】 coronavirus disease, neutralizing antibody, IgG, Coronavirus disease 2019, Vaccine development, coronavirus, antibody, SARS-COV-2 infection, children, COVID-19 pandemic, Antibody Response, Infection, immune system, severe acute respiratory syndrome Coronavirus, Asymptomatic, longitudinal study, anti-SARS-CoV-2 IgG, symptomatic, immune responses, age, antibody levels, humoral immune response, respiratory, humoral immune responses, South Korea, positive rate, Anti-spike, antibody level, anti-S IgG, geometric mean, symptom onset, acute respiratory syndrome, acute respiratory syndrome coronavirus, acute respiratory syndrome coronavirus 2, Blood samples, blood sample, geometric mean titers, GMTs, Cutoff, positive rates, positive, geometric mean titer, feature, effective, highest, analyzed, evaluate, caused, peaked, remained, detectable, conducted, reached, were measured, children with COVID-19, GMT, with COVID-19, 【제목키워드】 response,