TABLE 2.
Samples collected and influenza A virus prevalence from migratory waterfowl in North America between 1976 and 2015, stratified by various predictors
| Predictor | No. samples | Percent IAV prevalence (no. isolates) |
|---|---|---|
| Decade | ||
| 1976–1985 | 11,361 | 24 (2,749) |
| 1986–1995 | 2,721 | 11 (304) |
| 1996–2005 | 3,624 | 8 (303) |
| 2006–2015 | 60,263 | 8 (5,071) |
| Location | ||
| Alberta | 16,523 | 22 (3,626) |
| Arkansas | 1,772 | 2 (37) |
| Illinois | 4,857 | 3 (150) |
| Indiana | 804 | 0.3 (2) |
| Iowa | 183 | 14 (26) |
| Louisiana | 5,725 | 4 (247) |
| Michigan | 190 | 6 (11) |
| Minnesota | 14,396 | 15 (2,219) |
| Mississippi | 3,176 | 3 (94) |
| Missouri | 5,181 | 3 (156) |
| North Dakota | 1,050 | 9 (96) |
| Ohio | 12,731 | 8 (975) |
| Ontario | 357 | 5 (18) |
| Quebec | 7 | |
| Tennessee | 3 | |
| Texas | 7,226 | 7 (520) |
| Wisconsin | 3,788 | 7 (250) |
| Gender | ||
| Female | 29,242 | 12 (3,520) |
| Male | 42,981 | 11 (4,620) |
| Unknown | 5,746 | 5 (287) |
| Age | ||
| Juvenile | 41,296 | 15 (6,387) |
| Adult | 31,439 | 6 (1,779) |
| Unknown | 5,234 | 5 (261) |
| Season | ||
| Summer | 23,829 | 19 (4,457) |
| Fall | 38,792 | 9 (3,501) |
| Winter | 9,507 | 3 (253) |
| Spring | 5,841 | 4 (216) |