Table. Estimated incubation period of 24 human cases of infection with avian influenza A virus (H5N1), China*.

Exposure data	Case-patients with exposure to sick/ dead poultry only	Case-patients with exposure to wet poultry market only	p value	All case-patients
No. case-patients with exposures on multiple days	12	6		18
Overall median incubation period, d (range)	4.5 (2–9.5)	6.3 (3.5–7)	0.276	5 (2–9.5)
Median of minimum incubation period, d (range)	1 (0–5)	0 (0–2)	0.315	0.5 (0–5)
Median of maximum incubation period, d (range)	7.5 (4–14)	11.5 (7–14)	0.108	8.5 (4–14)
No. case-patients with single known exposure	4	2		6
Overall median incubation period, d (range)	3.5 (2–6)	8.5 (8–9)	0.064	5 (2–9)
All case-patients	16	8		24
Overall median incubation period, d (range)	4.3 (2–9)	7 (3.5–9)	0.045	5 (2–9.5)
Overall median of minimum incubation period, d (range)	1.5 (0–6)	1 (0–9)	0.752	1.5 (0–9)
Overall median of maximum incubation period, d (range)	6 (2–14)	9 (7–14)	0.031	7.5 (2–14)

*Boldface represents significant results (Wilcoxon rank-sum test).