A tuberculosis-free calf, stomach shaved, would be bound to an operating table, where incisions would be made on its lower body. Glycerinated lymph from a previously inoculated calf was spread along the cuts. After a few days, the cuts would have scabbed or crusted over. The crust was softened with sterilized water and mixed with glycerin, which disinfected it, then stored hermetically sealed in capillary tubes for later use.At some point, the virus in use was no longer cowpox, but vaccinia. Scientists have not determined exactly when the change or mutation occurred, but the effects of vaccinia and cowpox virus as vaccine are nearly the same.The virus is found in Europe, and mainly in the UK. Human cases today are very rare and most often contracted from domestic cats. The virus is not commonly found in cattle; the reservoir hosts for the virus are woodland rodents, particularly voles. From these rodents, domestic cats contract and transmit the virus to humans. Symptoms in cats include lesions on the face, neck, forelimbs, and paws, and less commonly upper respiratory tract infections. Symptoms of infection with cowpox virus in humans are localized, pustular lesions generally found on the hands and limited to the site of introduction. The incubation period is 9 to 10 days. The virus is prevalent in late summer and autumn. Origin
Discovery
In the years from 1770 to 1790, at least six people who had contact with a cow had independently tested the possibility of using the cowpox vaccine as an immunization for smallpox in humans.
Pruritus of genital organs may refer to:

Pruritus scroti
Pruritus vulvae