Robovirus

[6] Potential sites of contact with rodents include habitats such as barns, outbuildings, sheds, and dense urban areas.

When these rats scavenge and enter households this provides an outlet for direct contact transmission with humans.

The virus is caused by a Rocky Mountain wood tick (Dermacentor andersoni).

The tick is carried by five species of rodents: the least chipmunk (Eutamias minimus), Richardson's ground squirrel (Urocitellus richardsonii), deer mice (Peromyscus maniculatus), the golden-mantled ground squirrel (Callospermophilus lateraliss), and the Uinta chipmunk (Neotamias umbrinus).

[12] Rodent populations are affected by a number of diverse factors, including climatic conditions.

A highly magnified image of a virus alongside cell debris
Electron micrograph of the Robovirus responsible for Lassa fever