Murine leprosy is a leprosy-like disease of rats and mice, caused by
Mycobacterium lepraemurium. The disease affects primarily viscera and the skin,
and very rarely peripheral nerves. Depending on the host strain, rodent leprosy
may also evolve as 'lepromatous' or 'tuberculoid' leprosy, and strains of mouse
that develop intermediate forms of the disease may exist. Growth of
M. lepraemurium on conventional media for mycobacteria is not successful, but
the bacterium has been cultured on an egg yolk-based medium. Naturally
acquired murine leprosy has been observed in rats, mice and cats, but not in
humans or any other species. Thus, in contrast to human leprosy, murine leprosy
is not a zoonosis.