Table A3. Prevalence of highly pathogenic avian influenza (H5N1) infection in wild birds, 2004–2007, Thailand *.

Characteristic	No. infected birds	No. tested birds	Prevalence, % (95% CI)
Type of bird
Migratory	4	2,142	0.187 (0.01–0.21)
Resident	138	16,633	0.829 (0.66–0.94)
Breeding visitor	50	6,143	0.814 (0.61–0.99)
Regions
North	13	5,321	0.24 (0.1–0.3)
Central-Northwest	77	4,510	1.71 (1.38–2.02)
Central-North	30	4,075	0.74 (0.49–0.91)
Central-Central	54	5,327	1.01 (0.78–1.22)
Central-East	1	1,462	0.07 (0.02–0.32)
Central-Southeast	21	2,083	1.01 (0.64–1.36)
Central-Southwest	3	1,713	0.18 (0–0.23)
Northeast	5	2,298	0.22 (0.05–0.35)
South	8	2,348	0.34 (0.11–0.49)
Seasons, y
Winter (January –February), 2004	29	366	7.92 (5.8–10.4)
Summer (March–June), 2004	27	229	11.79 (8.7–15.8)
Rainy (July–October), 2004	9	359	2.51 (1.51–4.32)
Winter (November–December), 2004 and (January–February), 2005	19	1,027	1.85 (1.29–2.70)
Summer (March–June), 2005	12	611	1.96 (1.26–3.15)
Rainy (July–October), 2005	25	8,026	0.31 (0.22–0.43)
Winter (November–December), 2005 and (January–February ), 2006	19	1,317	1.44 (1.00–2.10)
Summer (March–June), 2006	7	3,768	0.19 (0.11–0.32)
Rainy (July–October), 2006	17	4,528	0.38 (0.25–0.56)
Winter (November–December), 2006 and (January–February), 2007	44	3,261	1.35 (1.06–1.73)
Summer (March–June), 2007	4	3,032	0.13 (0.06–0.30)
Rainy (July–October), 2007	0	2,338	NA
Winter (November–December), 2007	0	652	NA

*CI, confidence interval; NA, not applicable.