Cowpox

Cowpox is a skin disease caused by a virus known as the Cowpox virus. The pox is related to the vaccinia virus and got its name from the distribution of the disease when dairymaids touched the udders of infected cows. The ailment manifests itself in the form of red blisters and is transmitted by touch from infected animals to humans. Cowpox is similar to but much milder than the highly contagious and sometimes deadly smallpox disease. It resembles mild smallpox, and was the basis of the first smallpox vaccines. When the patient recovers from cowpox, the person is immune to smallpox.

The cowpox virus was used to perform the first (by Western physicians that is. Prior to this, traditional female healers in Turkey, along with those in Africa and a number of African Americans practiced the use of pus from healed smallpox pustules to induce immunization) successful vaccination against a disease, smallpox, which is caused by the related Variola virus. Therefore, the word "vaccination" — first used by Edward Jenner (an English physician) in 1796 — has the Latin root vaccinus meaning of or from cows. World Health Organization in 1980 announced that smallpox was the first disease that had been eradicated world wide by a program of vaccination. Despite the eradication of smallpox in the past century, other orthopoxviruses, such as monkeypox virus, vaccinia virus in Brazil, and cowpox virus (CPXV) in Europe, still infect humans. CPXV has been restricted to the Old World with wild rodents as its natural reservoir. Human CPXV infections are commonly described in relation to contact with diseased domestic cats, sometimes directly from rats or domesticated house mice. Human infections usually remain localized and self-limiting but can become fatal in immunosuppressed patients.