BACKGROUND:

Children with SARS-CoV-2 infection typically have mild symptoms that do not require medical attention, leaving a gap in our understanding of the spectrum of illnesses that the virus causes in children.

METHODS:

We conducted a prospective cohort study of children and adolescents (< 21 years of age) with a SARS-CoV-2-infected close contact. We collected nasopharyngeal or nasal swabs at enrollment and tested for SARS-CoV-2 using a real-time PCR assay.

RESULTS:

Of 382 children, 289 (76%) were SARS-CoV-2-infected. SARS-CoV-2-infected children were more likely to be Hispanic (p< 0.0001), less likely to have a history of asthma (p= 0.009), and more likely to have an infected sibling contact (p= 0.0007) than uninfected children. Children ages 6–13 years were frequently asymptomatic (38%) and had respiratory symptoms less often than younger children (30% vs. 49%; p= 0.008) or adolescents (30% vs. 59%; p< 0.0001). Compared to children ages 6–13 years, adolescents more frequently reported influenza-like (61% vs. 39%; p= 0.002), gastrointestinal (26% vs. 9%; p= 0.003), and sensory symptoms (43% vs. 9%; p< 0.0001), and had more prolonged illnesses [median (IQR) duration: 7 (4, 12) vs. 4 (3, 8) days; p= 0.004]. Despite the age-related variability in symptoms, we found no differences in nasopharyngeal viral load by age or between symptomatic and asymptomatic children.

CONCLUSIONS:

Hispanic ethnicity and an infected sibling close contact are associated with increased SARS-CoV-2 infection risk among children, while a history of asthma is associated with decreased risk. Age-related differences in the clinical manifestations of SARS-CoV-2 infection must be considered when evaluating children for COVID-19 and in developing screening strategies for schools and childcare settings.