The latest results of the Corona-Kinderstudie have just been made available as a preprint; you can access it here.
The preprint, entitled “Typically asymptomatic but with robust antibody formation: children’s unique humoral immune response to SARS-CoV-2“, demonstrates that children develop long-term immunity to COVID-19, even though SARS-CoV-2 infections are aysmptomatic five times more often in children than in adults.
The Corona-Kinderstudie is a large, multi-center study that aims to investigate COVID-19 in children; in particular, the course of COVID-19 infection in children, protection after a mild course, and the role they play in the pandemic as carriers, foci, and amplifiers of infection. The study was initiated and financed by the state of Baden-Württemberg.
328 households where at least one family member had had a confirmed COVID-19 infection took part. All family members in these households (548 children aged 1 to 18 years and 717 adults) took part at two timepoints by providing blood samples and completing questionnaires. By looking for antibodies against SARS-CoV-2 in the blood samples, the researchers were able to establish that children were significantly less likely to become infected than adults (34 percent vs. 58 percent).
If children were infected, they were five times more likely to have had no symptoms (adults: 9 percent, children 45 percent). Nevertheless, the children showed stronger and longer-lasting specific antibody levels than adults 11 to 12 months after infection. This was true whether or not symptoms were present. Childrens’ antibodies were also effective against different viral variants, which suggests that even children who are not visibly ill should be protected after infection.
Adults and children also reported having a different pattern of symptoms; whereas fever, cough, diarrhea, and taste disturbance were equally good indicators of infection in adults, only taste disturbance was a clear indicator of COVID-19 infection in children (in 87 percent). Cough and fever were indicative of infection only with increasing age from about 12 years.
In summary, it appears that children recovered from COVID-19 develop very effective and persistent immune defenses against new coronavirus infections despite an often very mild or even symptom-free course. These are indications that the children’s immune defenses against SARS-CoV-2 surpass those of adults.
The Freiburg leaders of the Corona-Kinderstudie are Philipp Henneke and Roland Elling; more information about the study (in German) is available here.