Table 3 Ranked factors identified for canine seroprevalence models of infections transmitted by Ixodes spp. in the USA

1.

Forest cover/NDVI or EVI^a

2.

Relative humidity

3.

Annual precipitation (including snow cover)^a

4.

Human population density^a

5.

Deer/vehicle collisions^a

6.

Topography/altitude/aspect

6.

Temperature – max warmest, min coldest^a

7.

Proximity of forest to impervious surfaces or roads/built environment

8.

Human case distribution

8.

Distribution/abundance of I. scapularis and I. pacificus^a

9.

Household income^a

10.

Forest fragmentation index^a