SPADA

Two distinct groups within Type A

Vectors

Hosts

f d • Type A.I. oun in eastern Nort America an west coast • Type A.II. found in western North America • These distributions are correlated with the distributions of  specific mammal hosts and tick/fly vectors d h

From Farlow et al. 2005

Three major subgroups in A.I

Lower virulence  in mice

Higher virulence  in mice

Tree from Birdsell et al. 2014 Mouse data from Molins et al. 2010