Long-term immune response to SARS-CoV-2 infection and vaccination in children and adolescents

Background: This analysis examined the durability of antibodies present after SARS-CoV-2 infection and vaccination in children and adolescents. Methods: Data were collected over 4 time points between October 2020-November 2022 as part of a prospective population-based cohort aged 5-to-19 years (N=810). Results of the (1) Roche Elecsys((R)) Anti-SARS-CoV-2 Immunoassay for detection of antibodies to the SARS-CoV-2 nucleocapsid protein (Roche N-test); and (2) qualitative and semi-quantitative detection of antibodies to the SARS CoV-2 spike protein receptor binding domain (Roche S-test); and (3) self-reported antigen/PCR COVID-19 test results, vaccination and symptom status were analyzed. Results: N antibody levels reached a median of 84.10 U/ml (IQR: 20.2, 157.7) cutoff index (COI)similar to 6 months post-infection and increased slightly to a median of 85.25 (IQR: 28.0, 143.0) COI at 12 months post-infection. Peak S antibody levels were reached at a median of 2500U/mL similar to 6 months post-vaccination and remained for similar to 12 months (mean 11.6 months, SD 1.20). Conclusions: This analysis provides evidence of robust durability of nucleocapsid and spike antibodies in a large pediatric sample up to 12 months post-infection/vaccination. This information can inform pediatric SARS-CoV-2 vaccination schedules.