Table 1.
Active serosurveillance for influenza A virus infection in the Norwegian pig population. Number of herd tests by county (n = 19) from 2010 to 2014
| County | 2010 | 2011* | 2012 | 2013 | 2014 | Total |
|---|---|---|---|---|---|---|
| Østfold | 44 | 89 | 95 | 95 | 50 | 373 |
| Akershus/Oslo | 27 | 79 | 59 | 47 | 36 | 248 |
| Hedmark | 41 | 126 | 152 | 131 | 120 | 570 |
| Oppland | 31 | 109 | 94 | 102 | 69 | 405 |
| Buskerud | 8 | 37 | 44 | 41 | 24 | 154 |
| Vestfold | 37 | 84 | 91 | 79 | 66 | 357 |
| Telemark | 8 | 28 | 29 | 25 | 28 | 118 |
| Aust-Agder | 2 | 5 | 1 | 6 | 6 | 20 |
| Vest-Agder | 4 | 17 | 12 | 9 | 6 | 48 |
| Rogaland | 145 | 289 | 338 | 424 | 317 | 1513 |
| Hordaland | 15 | 24 | 26 | 34 | 20 | 119 |
| Sogn og Fjordane | 14 | 6 | 27 | 27 | 23 | 97 |
| Møre og Romsdal | 4 | 11 | 21 | 20 | 20 | 76 |
| Sør-Trøndelag | 14 | 52 | 44 | 57 | 50 | 217 |
| Nord-Trøndelag | 69 | 291 | 281 | 212 | 196 | 1049 |
| Nordland | 22 | 40 | 44 | 72 | 61 | 239 |
| Troms/Finnmark | 5 | 1 | 3 | 20 | 11 | 40 |
| Total | 490 | 1288 | 1361 | 1401 | 1103 | 5643 |
*
A change in sampling strategy beginning in 2011 where the same herd could be tested more than once in the same year. Sampling took place at the slaughterhouses.