Table 2. Comparison of season-related positive rate against the selected diseases for layer flocks monitored from 2015 to 2017
| Disease | No. flock positive/no. flock tested (%) |
| LPAIa | NDb | IBc | aMPVd | EDS’76e | IBDf | CIAg | MSh |
| Spring | 731/838(87.2) | 830/833(99.6) | 742/776(95.6) | 191/234(78.6) | 107/118(90.7) | 18/18(100) | 8/13(61.5) | 23/59(39) |
| Summer | 672/809(83.1) | 815/816(99.9) | 697/740(94.2) | 188/236(79.7) | 93/117(79.5) | 15/16(93.8) | 5/5(100) | 52/94(55.3) |
| Fall | 763/961(79.4) | 958/964(99.4) | 825/874(94.4) | 169/264(64) | 108/155(69.7) | 8/8(100) | 4/5(80) | 24/62(38.7) |
| Winter | 540/632(85.4) | 608/608(100) | 533/564(94.5) | 163/204(79.9) | 76/96(79.2) | 17/19(89.5) | 9/16(56.3) | 21/55(38.2) |
LPAI, low pathogenic avian influenza; ND, Newcastle disease; IB, infectious bronchitis; aMPV, avian metapneumovirus infection; EDS’76, egg drop syndrome’ 76; IBD, infectious bursal disease; CIA, chicken infectious anemia; MS, Mycoplasma synoviae.