A Prospective Study of the Serological, Clinical, and Epidemiological Features of a SARS-CoV-2 Positive Pediatric Cohort.

ABSTRACT

BACKGROUND: SARS-CoV-2 was a global pandemic. Children develop a mild disease and may have a different rate of seroconversion compared to adults. The objective was to determine the number of seronegative patients in a pediatric cohort. We also reviewed the clinical-epidemiological features associated with seroconversion. METHODS: A multicenter prospective observational study during September-November 2020, of COVID-19, confirmed by reverse transcription-polymerase chain reaction. Data were obtained 4-8 weeks after diagnosis. Blood samples were collected to investigate the humoral response, using three different serological methods. RESULTS: A total of 111 patients were included (98 symptomatic), 8 were admitted to hospital, none required an Intensive Care Unit visit. Median age 88 months (IQR 24-149). Median time between diagnosis and serological test 37 days (IQR 34-44). A total of 19 patients were non-seroconverters when using three serological techniques (17.1%; 95% CI 10.6-25.4); most were aged 2-10 years (35%, p < 0.05). Univariate analysis yielded a lower rate of seroconversion when COVID-19 confirmation was not present amongst household contacts (51.7%; p < 0.05). CONCLUSIONS: There was a high proportion of non-seroconverters. This is more commonly encountered in childhood than in adults. Most seronegative patients were in the group aged 2-10 years, and when COVID-19 was not documented in household contacts. Most developed a mild disease. Frequently, children were not the index case within the family.