Progression of myxomatosis (illustrated)
After an insect has penetrated the skin and inoculated a rabbit with the pox virus that causes myxomatosis, replication of the virus takes place at the inoculation site in the regional lymph node. The rabbit becomes viraemic as infection is disseminated throughout the body. The disease starts with a skin lesion, which typically develops 4-5 days after inoculation of the virus and is not often observed. The eyelids show the first obvious sign of infection as they redden and become thickened until the eyes are closed, often completely, with a semipurulent ocular discharge. Secondary nodular, crusty lesions develop throughout the body, typically on the nares, lips, eyelids and base of the ears and on the external genitalia and anus. The course of the disease runs for several weeks depending on the virulence of the strain and the immunity of the rabbit. Recovery is possible although scars may remain on the areas that had nodular lesions.