Table 2. Association of shedding and positive immune responses in 57 animals followed between 1 to 9 years (with a median follow up time of 2.95 years).
| Characteristic | Shedding status in each group (CFU) | |||
|---|---|---|---|---|
| All animals | Group 2 | Group 3 | ||
| Age at baseline | OR (95% CI) | 1.17 (1.01–1.37) | 1.07 (0.78–1.47) | 1.07 (0.83, 1.37) |
| AOR (95% CI) | 1.08 (0.94–1.24) | 1.08 (0.86–1.36) | 0.99 (0.80–1.23) | |
| Interferon gamma (IFN-γ) status | OR (95% CI) | 2.13 (1.45–3.13) | 1.67 (0.95–2.91) | 2.96 (1.22–7.19) |
| AOR (95% CI) | 1.75 (1.02–2.99) | 1.42 (0.72–2.77) | 0.54 (0.09–3.44) | |
| Elisa status | OR (95% CI) | 6.81 (3.87–12.0) | 3.78 (1.40–10.2) | 3.05 (1.02–9.15) |
| AOR (95% CI) | 3.97 (1.53–10.3) | 2.65 (9, 55–12.9) | 0.66 (0.13–3.31) | |
| ELISA and INF-γ status | OR (95% CI) | 9.09 (5.18–16.0) | 5.78 (2.24–14.9) | 3.78 (1.44–9.90) |
| AOR (95% CI) | 2.30 (0.76–6.94) | 2.68 (0.41–17.6) | 7.07 (0.81–61.7) | |
The estimated odds ratios (effects) are based on generalized estimating equations. INF-γ status was defined as a categorical variable with changes greater than 0.10 deemed positive and those less than 0.10 negative. ELISA status was defined as a categorical variable with antibody changes greater than 0.25 deemed positive and those less than 0.25 negative. CFU was categorized as shedding (values greater or equal to 1) and no shedding (values equal to zero). Group 2: animals with a combined immune response. Group 3: animals with progression of infection. OR: adds ratio; AOR – adjusted odds ratio.