| Before Delta and omicron emergence | After Delta emergence | After Omicron emergence | References |
---|---|---|---|---|
Median Incubation period | 5–7.5 days | 3.7–6 days | 2–3 days | |
Emergency department visit | ||||
0–4 years | NI | 21.01% | 3.89% | [61] |
5–11 years | NI | 12.62% | 3.60% | [61] |
Intensive care unit admission rate | ||||
Under 1Â year | NI | 14.00% | 9.90% | [23] |
< 18 years | 26.5% 0.10% | 23.2% 1.40% | NI NI | [120] [54] |