Table 2:

Comparison of persistent symptoms in children infected with SARS-CoV-2 to controls

Country (Reference)	Age group	Cases with new symptoms at follow-up	Controls with new symptoms at follow-up	Absolute difference	Odds ratio (95% CI); p-value or other comparisons
Published studies
Denmark (6)	0–3 y	478/1,194 (40.0%)	1,049/3,855 (27.2%)	12.8%	1.78 (1.55–2.04); p <0.0001
	4–11 y	1,912/5,023 (38.1%)	6,189/18,372 (33.7%)	4.4%	1.23 (1.15–1.31); p <0.0001
	12–14 y	1,313/2,857 (46.0%)	4,454/10,789 (41.3%)	4.7%	1.21 (1.11–1.32); p <0.0001
8 countries (7)	0–18 y (inpatients)	40/391 (10.2%)	19/380 (5.0%)	5.2%
	0–18 y (outpatients)	55/1,295 (4.2%)	35/1,321 (2.7%)	1.6%
	0–18 y (all patients)				1.63 (1.14–2.35)
Latvia (8)	1 mo to18 y	152/217 (70%)	32/129 (25%)	45%	p <0.0001
Switzerland (9)	6–16 y	4/109 (2%)	28/1,246 (4%)	2.0%	NR
England (10)	11–17 y: 3 or more symptoms at follow-up	936/3,065 (30.5%)	603/3,739 (16.1%)	14.4%
	11–17 y: any symptoms at follow-up	2,038/3,065 (66.5%)	1,993/3,739 (53.3%)	13.2%	p <0.0001
UK (11)	5–17 y	77/1,734 (4.4%)*	15/1,734 (0.9%)	3.5%	p <0·0001
England (12)	2–16 y	21/320 (6.7%)	6/154 (4.2%)	2.5%	p = 0.24
Denmark (13)	0–5 y	439/2,979 (14.8%)	1,201/6,832 (17.6%)	–2.8%	p = 0.001
	6–17 y	3,374/12,065 (28.0%)	2,245/8,248 (27.2%)	0.8%	p = 0.02
United States (14)	0–17 y	N = 781,419	N = 2,344,257		Increased incidence of 5 symptoms and 6 conditions, decreased incidence of 1 symptom and 3 conditions and no change for 3 symptoms and 6 conditions
7 countries (15)	0–17 y	36,592/185,748 (19.7%)	39,193/185,748 (21.1%)	–1.4%	p = 0.29
Preprints
UK and Wales (16)	0–17 y	8/174 (4.6%)	72/4504 (1.6%)	3.0%	2.48 (1.00–6.13)
Germany (17)	Grade 8–12	N = 188	N = 1365		No difference in cases versus controls for any of the 7 symptoms and 5 moods
Germany (18)	Children/adolescents	437/1000 patient-years	336/1000 patient-years		IRR = 1.33 (1.31–1.34)

* 25/1,379 cases (1.8%) had symptoms at 56 days, but data are not reported for controls

NR = Not reported; IRR = Incidence rate ratio; UK = United Kingdom