RESUMO
BackgroundLong-term persistence of antibodies against SARS-CoV-2, particularly the SARS-CoV-2 Spike Trimer, determines individual protection against infection and potentially viral spread. The quality of childrens natural humoral immune response following SARS-CoV-2 infection is yet incompletely understood but crucial to guide pediatric SARS-CoV-2 vaccination programs. MethodsIn this prospective observational multi-center cohort study, we followed 328 households, consisting of 548 children and 717 adults, with at least one member with a previous laboratory-confirmed SARS-CoV-2 infection. The serological response was assessed at 3-4 months and 11-12 months after infection using a bead-based multiplex immunoassay for 23 human coronavirus antigens including SARS-CoV-2 and its Variants of Concern (VOC) and endemic human coronaviruses (HCoVs), and additionally by three commercial SARS-CoV-2 antibody assays. ResultsOverall, 33.76% of SARS-CoV-2 exposed children and 57.88% adults were seropositive. Children were five times more likely to have seroconverted without symptoms compared to adults. Despite the frequently asymptomatic course of infection, children had higher specific antibody levels, and their antibodies persisted longer than in adults (96.22% versus 82.89% still seropositive 11-12 months post infection). Of note, symptomatic and asymptomatic infections induced similar humoral responses in all age groups. In symptomatic children, only dysgeusia was found as diagnostic indicator of COVID-19. SARS-CoV-2 infections occurred independent of HCoV serostatus. Antibody binding responses to VOCs were similar in children and adults, with reduced binding for the Beta variant in both groups. ConclusionsThe long-term humoral immune response to SARS-CoV-2 infection in children is robust and may provide long-term protection even after asymptomatic infection. (Study ID at German Clinical Trials Register: 00021521)
RESUMO
In light of the COVID-19 pandemic, universities around the world were challenged by the difficult decision whether classes could be held face-to-face in the winter semester 20/21. The gross anatomy course is considered an essential practical element of medical school. In order to protect the participants and teaching staff and to gain more knowledge about SARS-CoV-2 infections among students during a semester with face-to-face teaching a longitudinal test study was conducted. Medical students from the first three years of medical school were also invited. Out of a total of almost 1,000 swabs, only two active asymptomatic infections were detected at the start of the semester, none during the semester. At semester start, approximately 6% of the students had antibodies. At the end of the semester, only nine seroconversions after infection in 671 individuals occurred. This was surprisingly low because a massive second wave of infections hit Germany during the same period. The conclusion therefore is that face-to-face teaching under these measures was not infection-promoting even with high incidence rates in the overall population with the SARS-CoV-2 variants present at that time period. Moreover, the results are indicative of a preventive effect of hygiene concepts together with repetitive testings before and during a semester.
