Table 2.

SARS-CoV-2 incubation period by variant, observed and corrected for day 5 to day 9

	N	Observed, days		Correction for days 5 to 9, days
		Mean (95% CI)	SD	Mean (95% credible interval)	SD
Historical	7539	4·61 (4·56–4·66)	2·24	4·57 (4·52–4·62)	2·22
Alpha	5133	4·96 (4·90–5·02)	2·32	4·92 (4·85–4·98)	2·31
Beta or gamma	453	5·18 (4·93–5·43)	2·72	5·15 (4·90–5·40)	2·72
Delta	4606	4·43 (4·36–4·49)	2·19	4·40 (4·33–4·46)	2·17
Omicron	2682	3·61 (3·55–3·68)	1·82	3·58 (3·52–3·65)	1·77
Total	20 413	4·54 (4·51–4·57)	2·25	4·50 (4·47–4·53)	2·23

A gamma distribution was fitted to estimate probability of rounding the estimation to 7 days if the underlying incubation period was 6 days or 8 days, or 5 days or 9 days. The included variants are alpha (B.1.1.7), beta (B.1.351), gamma (P.1), delta (B.1.617.2), and omicron (B.1.1.529).