ABSTRACT
BACKGROUND: Data regarding humoral and cellular response against SARS-CoV-2 in children are scarce. We analysed seroconversion rate, decrease of anti-RBD IgG antibodies over time and T-cell response in paediatric patients who suffered COVID-19. METHODS: Longitudinal study of paediatric patients COVID-19 diagnosed by positive molecular assay in nasopharyngeal swabs. Blood samples were drawn 1-2 months and 6-7 months after acute infection. Anti-RBD IgG were determined using the Alinity® SARS-CoV-2 IgG II Quant assay (Abbott). Cellular immune response was analysed by T-SPOT® SARS-CoV-2 assay kit (Oxford Immunotec Ltd.). RESULTS: 27/39 (69,2%) patients seroconverted. Despite a significant decrease in antibody levels over time (p < 0,01), no children seroreverted between first and second visits. Only 6/16 (37,2%) children under 6 years-old were seropositive compared to 21/23 (91,3%) over 6 years-old (p < 0,01). Highest antibody levels were found in seropositive younger children (p = 0,036). Thirteen (33,3%) children showed T-cell response. Among participants showing humoral response, no cellular response was detected in 14 (51,9%). CONCLUSIONS: Anti-RBD IgG antibodies persistence at 6-7-months after SARS-CoV-2 infection was observed. A different IgG response was found depending on age. As measured by T-SPOT, most patients did not display cellular response 6-7 months after infection.
Subject(s)
COVID-19 , Antibodies, Viral , Child , Child, Preschool , Humans , Immunoglobulin G , Longitudinal Studies , SARS-CoV-2ABSTRACT
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.
ABSTRACT
OBJECTIVE: To investigate the optic nerve and macular parameters of children who recovered from COVID-19 compared with healthy children using optical coherence tomography (OCT). DESIGN: Cohort study. SETTING: Hospital Clinico San Carlos, Madrid. PATIENTS: Children between 6 and 18 years old who recovered from COVID-19 with laboratory-confirmed SARS-CoV-2 infection and historical controls were included. INTERVENTIONS: All patients underwent an ophthalmological examination, including macular and optic nerve OCT. Demographic data, medical history and COVID-19 symptoms were noted. MAIN OUTCOME MEASURES: Peripapillary retinal nerve fibre layer thickness, macular retinal nerve fibre layer thickness, macular ganglion cell layer thickness and retinal thickness. RESULTS: 90 patients were included: 29 children who recovered from COVID-19 and 61 controls. Patients with COVID-19 presented an increase in global peripapillary retinal nerve fibre layer thickness (mean difference 7.7; 95% CI 3.4 to 12.1), temporal superior (mean difference 11.0; 95% CI 3.3 to 18.6), temporal inferior (mean difference 15.6; 95% CI 6.5 to 24.7) and nasal (mean difference 9.8; 95% CI 2.9 to 16.7) sectors. Macular retinal nerve fibre layer analysis showed decreased thickness in the nasal outer (p=0.011) and temporal inner (p=0.036) sectors in patients with COVID-19, while macular ganglion cell layer thickness increased in these sectors (p=0.001 and p=0.015, respectively). No differences in retinal thickness were noted. CONCLUSIONS: Children with recent history of COVID-19 present significant changes in peripapillary and macular OCT analyses.