FIG 1.

Incident rate ratios with 95% CIs for risk factors affecting the number of host-associated Ixodes ricinus ticks on wild mice. A negative binomial regression for the I. ricinus count (larvae and nymphs) as the dependent variable was performed using the H. polygyrus worm count and the categorical factors trapping location with three dummy variables and host species as independent variables. Reference categories for the trapping location and host species were Gatow and A. flavicollis, respectively. *, P < 0.05; ***, P < 0.001; n.a., not applicable because of total colinearity with the trapping location. Data are for 107 wild mice.