Definition of Cowpox

Cowpox: A mild skin disease of milk cows, principally confined to the udder and teats, that may be contracted by people from milking an infected cow. People develop vesicles (blebs) which break and form ulcers on the fingers (sometimes called "milkers nodules"). These usually heal without scarring. Cowpox protects against smallpox and was used by Edward Jenner in 1798 for this purpose to confer immunity against smallpox. Cowpox and smallpox belong to the orthopox family of viruses.