Long COVID symptoms in exposed and infected children, adolescents and their parents one year after SARS-CoV-2 infection: A prospective observational cohort study.

BACKGROUND: Long COVID in children and adolescents remains poorly understood due to a lack of well-controlled studies with long-term follow-up. In particular, the impact of the family context on persistent symptoms following SARS-CoV-2 infection remains unknown. We examined long COVID symptoms in a cohort of infected children, adolescents, and adults and their exposed but non-infected household members approximately 1 year after infection and investigated clustering of persistent symptoms within households. METHODS: 1267 members of 341 households (404 children aged <14 years, 140 adolescents aged 14-18 years and 723 adults) were categorized as having had either a SARS-CoV-2 infection or household exposure to SARS-CoV-2 without infection, based on three serological assays and history of laboratory-confirmed infection. Participants completed questionnaires assessing the presence of long COVID symptoms 11-12 months after infection in the household using online questionnaires. FINDINGS: The prevalence of moderate or severe persistent symptoms was statistically significantly higher in infected than in exposed women (36.4% [95% CI: 30.7-42.4%] vs 14.2% [95% CI: 8.7-21.5%]), infected men (22.9% [95% CI: 17.9-28.5%] vs 10.3% [95% CI: 5.8-16.9%]) and infected adolescent girls (32.1% 95% CI: 17.2-50.5%] vs 8.9% [95%CI: 3.1-19.8%]). However, moderate or severe persistent symptoms were not statistically more common in infected adolescent boys aged 14-18 (9.7% [95% CI: 2.8-23.6%] or in infected children <14 years (girls: 4.3% [95% CI: 1.2-11.0%]; boys: 3.7% [95% CI: 1.1-9.6%]) than in their exposed counterparts (adolescent boys: 0.0% [95% CI: 0.0-6.7%]; girls < 14 years: 2.3% [95% CI: 0·7-6·1%]; boys < 14 years: 0.0% [95% CI: 0.0-2.0%]). The number of persistent symptoms reported by individuals was associated with the number of persistent symptoms reported by their household members (IRR=1·11, p=·005, 95% CI [1.03-1.20]). INTERPRETATION: In this controlled, multi-centre study, infected men, women and adolescent girls were at increased risk of negative outcomes 11-12 months after SARS-CoV-2 infection. Amongst non-infected adults, prevalence of negative outcomes was also high. Prolonged symptoms tended to cluster within families, suggesting family-level interventions for long COVID could prove useful. FUNDING: Ministry of Science, Research and the Arts, Baden-Württemberg, Germany.

Pulmonary Function and Persistent Clinical Symptoms in Children and Their Parents 12 Months After Mild SARS-CoV-2 Infection.

Background: Pulmonary involvement is the leading cause of morbidity and mortality after severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. Long-term impairment has been reported in adults with severe infection. However, most infections cause only mild symptoms or are even asymptomatic, especially in children. There is insufficient evidence regarding pulmonary outcome measures in mild SARS-CoV-2. The objectives of this study were to determine spirometry parameters after SARS-CoV-2 infection and correlate those with reported persisting symptoms in children, adolescents, and adults. Methods: Data on clinical symptoms during acute infection as well as SARS-CoV-2 serology results were recorded. Twelve months after infection, spirometry was performed and information on persisting symptoms was collected using a structured questionnaire. 182 participants (108 SARS-CoV-2 positive) from 48 families were included; 53 children (< 14 years), 34 adolescents and young adults (14-25 years), and 95 adults. Results: Spirometry values did not significantly differ between the particular subgroups of the cohort (adults, adolescents, children; infected and non-infected individuals). Adults reported more symptoms during acute infection as well more persisting fatigue (29.7% of participants), reduced physical resilience (34.4%), and dyspnea (25.0%) 12 months after infection than adolescents (fatigue 26.7%, reduced physical resilience 20%, and 0% dyspnea) and children (4%, 0%, 0%, respectively). There was no correlation between persistent subjective symptoms and spirometry results. Discussion: Children and adolescents are less affected than adults by acute SARS-CoV-2 as well as by post-infection persistent symptoms. Spirometry was not able to demonstrate any differences between healthy individuals and participants who had suffered from mild SARS-CoV-2 12 months after the infection.

Robust and durable serological response following pediatric SARS-CoV-2 infection.

The quality and persistence of children's humoral immune response following SARS-CoV-2 infection remains largely unknown but will be crucial to guide pediatric SARS-CoV-2 vaccination programs. Here, we examine 548 children and 717 adults within 328 households with at least one member with a previous laboratory-confirmed SARS-CoV-2 infection. We assess serological response 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. Neutralization against wild type SARS-CoV-2 and the Delta VOC are analysed in a pseudotyped virus assay. Children, compared to adults, are five times more likely to be asymptomatic, and have higher specific antibody levels which persist longer (96.2% versus 82.9% still seropositive 11-12 months post infection). Of note, symptomatic and asymptomatic infections induce similar humoral responses in all age groups. SARS-CoV-2 infection occurs independent of HCoV serostatus. Neutralization responses of children and adults are similar, although neutralization is reduced for both against the Delta VOC. Overall, the long-term humoral immune response to SARS-CoV-2 infection in children is of longer duration than in adults even after asymptomatic infection.