COVID-19 is generally mild in children, 1 and post-acute inflammatory conditions that are temporally associated with the virus are rare, but potentially severe. However, some children and adults experience persistent symptoms after COVID-19. 2 Long COVID has not been precisely defined, but one study reported symptoms approximately 60 days after the primary diagnosis. 3 Although adult long COVID is increasingly being studied, the magnitude of persistent symptoms in children remains unclear. This Swedish study assessed the extent, and type, of persistent symptoms in children aged 0-18 years who were admitted to one of the two paediatric hospitals in the Stockholm Region from 13 March to 31 August 2020 due to COVID-19. The inclusion criteria were the presence of a nasopharyngeal sample RT-PCR positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Children that tested positive, but were hospitalised for other reasons, were not included. Information on any persisting health issues following BRIEF REPORT

The burden of community-acquired pneumonia (CAP) in high-income countries is still significant. The introduction of pneumococcal conjugate vaccines (PCV) has reduced the overall need for hospitalization for CAP. However, it is not clear whether children with underlying disease also have benefitted from the PCV immunization programme. Children 0 to <5 years of age hospitalized with CAP and discharged with an ICD-10 code of J13-J18.9 between November 1, 2005, and April 30, 2007 (pre-vaccination period), and November 1, 2010, and April 30, 2012 (post-vaccination period), were eligible for this study. Data on hospitalization and discharge diagnoses were retrieved from the Hospital Registry. In addition, chart review was performed in 50% of the patients. Our result confirmed a decrease in hospitalization rate for CAP in the PCV13 period. Chart review revealed that half of the patients had underlying comorbidity and these children had more severe symptoms and required longer hospital stay. Intensive care was provided to less than 10% of the children and mostly for children with an underlying neurological disease. Conclusions: We show that all children have benefitted from the reduction of CAP hospitalization after introduction of PCV. Our finding emphasizes the importance of children with chronic diseases receiving adequate vaccinations that may protect from lower respiratory diseases. What is known? • Community-acquired pneumonia is a leading infectious cause of hospitalizations and death among children <5 years of age globally • Pneumococcal conjugate vaccine reduces the hospitalizations of all-cause pneumonia What is new? • We show that also children with underlying comorbidities have benefitted from PCV immunization with a reduction of CAP hospitalization • We show that approximately half of all children hospitalized with CAP also have underlying comorbidities.