Animals that may be infected with Orf virus:
(1) sheep
(2) goats
Source of virus:
(1) contact with an animal infected with Orf virus
(2) contact with an animal that has been recently immunized with a live Orf virus vaccine
(3) accidental innoculation with live Orf virus vaccine
(4) contact with a fomite contaminated with the virus (fence, feeding trough, stall, other)
Risk factors favoring infection:
(1) failure to use personal protective equipment around infected animals
(2) failure to wash the hands after animal contact
(3) recent traumatic injury
(4) immunocompromised
(5) bite from an infected animal