Milkers’ nodulesMilkers’ nodules are caused either by cowpox virus, an orthopoxvirus or pseudocowpox virus, a parapoxvirus. These are relatively benign lesions that occur most commonly on the hands or arms of people. The viruses are most commonly contracted by contact with cattle with teat lesions due to cowpox or pseudocowpox. The primary reservoir for cowpox virus is rodents. Human cowpox is usually a self- limited disease. The host immune response is usually sufficient to control the infection, and the only sequelae are scars at the site of the pox lesions.