Study design
A single-center prospective study was conducted from April 17, 2020 to September 30, 2020. Visits occurred at Hospital das Clínicas da Faculdade de Medicina da USP (HCFMUSP) in São Paulo, Brazil. The Ethics Committee of our Institution approve this study and written consent assignment was obtained from each patient before inclusion in the study.
We collected 1,566 respiratory samples from 1,044 patients younger than 18 years to assess SARS-CoV-2 infection. Of these, 919 were analyzed further in search of other respiratory pathogens (ORP). The samples were collected in pediatric patients with the following clinical findings: flu-like syndrome in high-risk children (<5 years or underlying conditions), fever without a source, severe acute respiratory syndrome (SARS), complete or incomplete Kawasaki Disease (KD), KD shock syndrome, MAS (macrophage-activating syndrome), gastrointestinal or neurological signs/symptoms.(4)
We included only patients with laboratory confirmed COVID-19 or ORP. In patients with high suspicion of COVID-19 but negative RT-PCR (real-time reverse transcription-polymerase chain reaction), serology was collected within 14 days of symptom onset. We excluded pre-surgical screenings or presence of bacterial coinfection.
Patients were divided in two groups: (a) Group 1 - laboratory confirmed pediatric COVID-19 patients without coinfection of ORP; (b) Group 2 - other respiratory virus infections, excluding SARS-CoV-2.