Table 2.
Distributions of predicted probabilities (%) for bovine tuberculosis outbreaks of various sizes in 10 dairy herds in Texas and New Mexico following detection of M bovis infection via slaughterhouse surveillance and clearance through test-based culling.10
| Herd No. | Herd size | Transmission method | Outbreak size category (No. of infected cattle) | ||||
|---|---|---|---|---|---|---|---|
| 0–10 | 11–20 | 21–30 | 31–40 | ≥ 41 | |||
| 1 | 160 | F | 95.7* | 3.7 | 0.6 | 0 | 0 |
| D | 96.5* | 3.2 | 0.3 | 0 | 0 | ||
| 2 | 280 | F | 94.3* | 5.3 | 0.3 | 0.1 | 0 |
| D | 92.1* | 6.6 | 1.2 | 0.1 | 0 | ||
| 3 | 370 | F | 95.4* | 4.1 | 0.4 | 0.1 | 0 |
| D | 89.5* | 8.6 | 1.4 | 0.3 | 0.2 | ||
| 4 | 600 | F | 95.0* | 4.3 | 0.5 | 0.2 | 0 |
| D | 83.4* | 11.5 | 3.1 | 1.7 | 0.3 | ||
| 5 | 1,200 | F | 95.8 | 3.4* | 0.7 | 0.1 | 0 |
| D | 79.6 | 13.8* | 7.9 | 4.8 | 2.9 | ||
| 6 | 1,400 | F | 95.3 | 4.1* | 0.5 | 1 | 0 |
| D | 69.4 | 13.2* | 7.9 | 5.3 | 4.2 | ||
| 7 | 1,500 | F | 95.2* | 4.4 | 0.4 | 0 | 0 |
| D | 69.0* | 13.8 | 6.8 | 4.6 | 5.8 | ||
| 8 | 3,700 | F | 94.8* | 4.2 | 1.0 | 0 | 0 |
| D | 54.3* | 10.5 | 8.8 | 7.4 | 19.0 | ||
| 9 | 5,000 | F | 94.8* | 4.2 | 0.7 | 0.2 | 0.1 |
| D | 54.3* | 7.1 | 9.5 | 6.8 | 22.3 | ||
| 10 | 7,300 | F | 94.3* | 5.2 | 0.5 | 0 | 0 |
| D | 54.4* | 2.9 | 6.0 | 6.3 | 30.4 | ||
Results for frequency-dependent (F) and density-dependent (D) transmission methods are shown.
*
Observed outbreak size category for the indicated herd.