Mousepox virus is the pathogen that causes mouse pox in mice. Mousepox virus can be transmitted directly from animal to animal through wounds on the skin or contaminants, most often through the spread of mouse footpads that cause infection.
When mouse pox virus infects mice via the subcutaneous route, it replicates at the site of infection and releases viral metabolites that spread to lymph nodes, blood, and other organs.
Virus invasion into the bloodstream triggers primary viremia, which allows the virus to enter the spleen and liver, where cellular necrosis releases more virus into the bloodstream, triggering secondary viremia, which is an important factor in the development of ulcers on the skin of mice.
Acutely infected mice die quickly; chronically infected mice develop ulcerated foci on the face, nose, and feet, and die in a diffuse, continuous manner; latently infected mice show no clinical signs, and the latent virus may erupt under stressful conditions.