Seroconversion rate to SARS- CoV-2 in an unselected cohort of children and mothers in certain region of North-Rhine-Westphalia (Ruhrgebiet)

Abstract: "Data on SARS-CoV-2/COVID-19 in children (until 18 years of age) is limited. Probably most of the infected children remain undetected due to the lack of clinical symptoms. The rate of seroconversion can be assessed by measuring SARS-CoV-2 IgA and IgG antibodies 2-4 weeks after the infection.The aim is to estimate the rate of seroconversion to SARS- CoV-2 in a large and unselected sample of asymptomatic children at defined time points (screening examinations in outpatient practices) in an urban region of North-Rhine-Westphalia. Symptoms and history of COVID-19 symptoms will be assessed and IgA and IgG antibodies measured. Possible risk factors for SARS- CoV-2 infection from the patient's history (e.g. co-morbidity, smoking exposure, social aspects etc.) will be detected. Frequency of infections and pulmonary symptoms in seropositive/negative children symptoms during the one year follow- up are recorded. Additionally, the rate of seroconversion in mother-child pairs (concordant vs discordant) will be evaluated in order to estimate the risk of exposure. Variations in ACE2 and TMPRSS2 will be measured since angiotensin I converting enzyme 2 (ACE2) and the transmembrane protease, serine 2 (TMPRSS2) l seem to play a crucial role for SARS-CoV-2 entry into host cells. Since different expression of these receptors could explain the differences in severity of COVID-19 infection in children vs. adults, a subgroup of children and mothers will be selected for later RNA analyses in nasal and oral mucosae."; Research Type: epidemiological study; Study population: children and adolescents