A skin disease, spontaneously occurring in captive Asiatic monkeys and transmissible to man, is caused by a poxvirus, which is probably not variola, vaccinia, monkeypox, Yaba, or orf. The histopathologic and electron microscopic characteristics of the lesion resemble, but are not identical with, those found in the known pox infections in monkeys. The possibility that this disease represents inadvertent introduction of one of the pox infections of domestic animals has not been excluded.
McNulty WP, Lobitz WC, Hu F, Maruffo CA, Hall AS. A Pox Disease in Monkeys Transmitted to ManClinical and Histological Features. Arch Dermatol. 1968;97(3):286-293. doi:10.1001/archderm.1968.01610090058008