Robust antibody response in children to acute COVID-19 infection and lasts for months.

Garrido C, Hurst JH, Lorang CG, Aquino JN, Rodriguez J, Pfeiffer TS, et al. Asymptomatic or mild symptomatic SARS-CoV-2 infection elicits durable neutralizing antibody responses in children and adolescents. JCI Insight 2021. https://doi.org/10.1172/jci.insight.150909

Question

Among children and adolescents with asymptomatic or mildly symptomatic SARS-CoV-2 infection, how do the specific antibody and neutralizing responses compare with those of adults?

Design

Two-group cohort study.

Setting

Duke University, Durham North Carolina.

Participants

Sixty nine children and adolescents (<21 years of age) with mild or asymptomatic acute SARS-CoV-2 infection, compared with 24 adults.

Intervention

Sera collected during acute infection and approximately 2 and 4 months later.

Outcomes

SARS-CoV-2–specific humoral immune and neutralizing responses.

Main Results

Both acute infection and 2 and 4 months later elicited strong IgM, IgG, and IgA antibody responses against SARS-CoV-2 antigens and were associated with neutralizing activity. These responses were as good or better than those elicited by adult sera.

Conclusions

Children and adolescents generate strong and durable antibody responses to SARS-CoV-2 infection.

Commentary

This study provided important data on the longitudinal change of SARS-CoV-2 antibody responses in children and adolescents with asymptomatic or mildly symptomatic infection. Similar to adults, SARS-CoV-2 IgM, IgG, IgA and neutralizing antibody responses persisted after 4 months of the acute infection. It would be interesting to follow up for a longer period of time as such evidence would be valuable for pediatric patient management and vaccination strategies. In addition to antibody levels, it is also important to evaluate the quality of antibody responses, such as dynamic changes of antibody binding avidity and T-cell responses in pediatric patients with COVID-19. Furthermore, this report demonstrated that SARS-CoV-2 specific antibody responses in children and adolescents were generally more robust and durable than those of adults with mild symptomatic infection. This finding was consistent with a previous study, which demonstrated higher IgG and surrogate neutralizing antibody activity as well as stronger antibody binding avidity in children compared with young adults. However, the antibody responses vary remarkably from young children, adolescences, and young adults, to elderly adults and adults with metabolic syndrome and chronic cardiovascular disease who exhibit higher IgG activity. The authors' conclusion would be strengthened if the patient cohort could be stratified based on more refined age ranges and comorbidities in both pediatric and adult populations using a larger sample size. It is also recommended to report assay analytical performance (eg, cutoff, linear range, precision, specificity) to demonstrate assay reliability.