TABLE 2.
Predictors of infection probability
| Term | Estimate | SE | OR | 95% CI | p | |
|---|---|---|---|---|---|---|
| H. majoris | Age | 0.65 | 0.28 | 1.91 | 1.11:3.29 | 0.02* |
| Host (GT) | 0.47 | 0.28 | 1.60 | 0.92:2.77 | 0.09 | |
| Season: Spring | 2.28 | 0.42 | 9.76 | 4.54:23.6 | <0.001* | |
| Season: Winter | −1.11 | 0.80 | 0.33 | 0.05:1.36 | 0.17 | |
| Year (2016) | −1.03 | 0.34 | 0.36 | 0.18:0.68 | 0.002* | |
| Year (2017) | −1.17 | 0.35 | 0.31 | 0.15:0.61 | <0.001* | |
| Elevation | 0.0004 | 0.0005 | — | — | 0.50 | |
| Host (GT) × Elevation | 0.0002 | 0.001 | — | — | 0.86 | |
| Host (GT) × Season: Spring | −0.46 | 0.89 | — | — | 0.60 | |
| Host (GT) × Season: Winter | −0.66 | 1.65 | — | — | 0.69 | |
| P. relictum | Age | 0.54 | 0.17 | 1.71 | 0.06:0.36 | 0.001* |
| Elevation | −0.0003 | 0.0006 | 0.9997 | 0.998:1.0008 | 0.60 | |
| Host (GT) | 1.75 | 0.48 | 5.77 | 2.26:14.72 | <0.001* | |
| Season: Spring | −0.39 | 0.23 | 0.67 | 0.43:1.06 | 0.09. | |
| Season: Winter | 0.14 | 0.22 | 1.15 | 0.74:1.79 | 0.53 | |
| Year (2016) | −0.33 | 0.19 | 0.72 | 0.49:1.05 | 0.09. | |
| Year (2017) | −0.54 | 0.24 | 0.58 | 0.36:0.93 | 0.02* | |
| Host (GT) × Elevation | −0.001 | 0.0007 | 0.998 | 0.997:1.00007 | 0.06. | |
| Host (GT) × Season: Spring | 0.74 | 0.44 | — | — | 0.09 | |
| Host (GT) × Season: Winter | 0.006 | 0.42 | — | — | 0.99 | |
| Season (Spring) × Year (2016) | 0.41 | 0.49 | — | — | 0.40 | |
| Season (Winter) × Year (2016) | −0.05 | 0.48 | — | — | 0.91 | |
| Season (Spring) × Year (2017) | −0.48 | 0.53 | — | — | 0.36 | |
| Season (Winter) × Year (2017) | na | na | — | — | na | |
| Leucocytozoon | Age | 0.83 | 0.17 | 2.3 | 1.66:3.20 | <0.001* |
| Group A | Elevation | 0.0006 | 0.0003 | 1.0006 | 0.9999:1.0012 | 0.057. |
| Host (GT) | 3.22 | 0.36 | 25.03 | 12.59:52.85 | <0.001* | |
| Season: Spring | 0.95 | 0.38 | 2.59 | 1.23:5.59 | 0.013* | |
| Season: Winter | −0.09 | 0.48 | 0.91 | 0.38:2.21 | 0.84 | |
| Year (2016) | −0.09 | 0.37 | 0.75 | 0.36:1.55 | 0.43 | |
| Year (2017) | −0.29 | 0.37 | 3.55 | 0.18:7.41 | <0.001* | |
| Host (GT) × Season: Spring | −1.55 | 0.45 | 0.21 | 0.09:0.51 | <0.001* | |
| Host (GT) × Season: Winter | −1.33 | 0.45 | 0.26 | 0.11:0.63 | 0.003* | |
| Season (Spring) × Year (2016) | 0.15 | 0.48 | 1.17 | 0.46:2.99 | 0.75 | |
| Season (Winter) × Year (2016) | 1.09 | 0.52 | 2.99 | 1.07:8.44 | 0.04* | |
| Season (Spring) × Year (2017) | −2.27 | 0.47 | 0.10 | 0.04:0.26 | <0.001* | |
| Season (Winter) × Year (2017) | na | na | na | na | na | |
| Host (GT) × Elevation | −0.0007 | 0.0006 | — | — | 0.29 | |
| Group D | Age | −0.63 | 0.21 | 0.53 | 0.35:0.80 | 0.003* |
| Host (GT) | −6.57 | 1.04 | 0.0014 | 0.00007:0.007 | <0.001* | |
| Season (Spring) | − 1.76 | 0.39 | 0.17 | 0.08:0.36 | <0.001* | |
| Season (Winter) | −0.30 | 0.43 | 0.74 | 0.31:1.74 | 0.49 | |
| Year (2016) | −0.39 | 0.62 | 0.68 | 0.21:2.44 | 0.52 | |
| Year (2017) | −0.45 | 0.41 | 0.63 | 0.28:1.41 | 0.27 | |
| Host (GT) × Season: Spring | 3.03 | 1.11 | 20.64 | 3.33:403.0 | 0.006* | |
| Host (GT) × Season: Winter | 2.22 | 1.15 | 9.24 | 1.30:187.5 | 0.053 | |
| Season (Spring) × Year (2016) | 2.09 | 0.71 | 8.12 | 1.92:31.81 | 0.003* | |
| Season (Winter) × Year (2016) | −0.27 | 0.75 | 0.76 | 0.65:3.25 | 0.72 | |
| Season (Spring) × Year (2017) | 2.01 | 0.53 | 7.49 | 2.65:21.62 | <0.001* | |
| Season (Winter) × Year (2017) | na | na | na | na | na | |
| Elevation | 0.0001 | 0.0005 | — | — | 0.68 | |
| Host (GT) × Elevation | −0.0007 | 0.001 | — | — | 0.53 |
Logistic regression results show the probability of infection by four focal parasites as a function of host species, host age category, season, elevation, and year. Host indicates host species, GT is great tit, blue tits served as the reference class. For season, autumn served as the reference class. For age class, first year birds (1) served as the reference class. And for year, 2015 served as the reference class. Terms retained in the final models are indicated in bold, and those significant at the <0.05 level are italicized and indicated with an asterisk. Odds ratio (OR) is provided for significant terms.