Children recovered from COVID-19 (N = 31) Uninfected Controls (N = 20)
Median age in years 12 14
Age range 2.7-18 8-15
Sex (%)
Male 45.2 (14/31) 80.0 (16/20)
Female 54.8 (17/31) 20.0 (4/20)
Residence (%)
Hong Kong 100 100
Ethnicity (%)
Han Chinese 80.6 (25/31) 80.0 (16/20)
Others 19.4 (6/31) 20.0 (4/20)
Travel history (%)
Yes 16.1 (5/31) N/A
No 83.9 (26/31) N/A
Disease awareness (%)
Asymptomatic 32.3 (10/31) N/A
Symptomatic 67.7 (21/31) N/A
Signs/symptoms (%)
Fever 61.9 (13/21) N/A
Cough 47.6 (10/21) N/A
Runny nose 28.6 (6/21) N/A
Ageusia 19.0 (4/21) N/A
Vomit 14.3 (3/21) N/A
Anosmia 9.5 (2/21) N/A
Sputum 4.9 (1/21) N/A
Headache 4.9 (1/21) N/A
SARS-CoV-2 PCR positivity (%)
Positive 100 (31/31) N/A
Negative 0 (0/31) 100(20/20)
SARS-CoV-2 anti-NP IgG positivity (%) 100 N/A
Sample collection period Dec2020 - March 2021 Dec2020 - March 2021
Recovery time (Days) 29-219 (Median=46.5) N/A