AETIOLOGY:

Poxvirus, a DNA virus antigenically related to the Shope fibroma virus. Different pathogenic strains. Susceptible to common disinfectants.

TRANSMISSION:

• Direct: secretions, etc. 
  
   
• Indirect: insect bites, needles, instruments used for artificial insemination and other fomites.  

CLINICAL SIGNS:

• Classical or nodular form: oedemas (eyelids, head – “big head disease” – perianal region, etc.), and nodules or myxoma in distal parts of the body (ears, muzzle, eyelids, etc.) and anogenital region. 
  
   
• Atypical or respiratory form: breathlessness, coryza, oedema and small myxomas.  

LESIONS:

• Classical or nodular form: blepharoconjunctivitis and myxomas. 
  
   
• Atypical or respiratory form: rhinitis, blepharitis, conjunctivitis, bleeding in the lungs and pneumonia, complicated by secondary bacterial agents (Pasteurella multocida, Bordetella bronchiseptica).  

DIAGNOSIS:

• Identification of the causative agent: inoculation in live animals or in cell culture, immunological methods (AGID, IIF) and electron microscopy. 
• Serology: CF and ELISA.  

TREATMENT, PREVENTION AND CONTROL:

• Biosecurity measures: insect control. Homologous live attenuated vaccines the antigen of which is the myxomatosis virus, and/or heterologous vaccines containing the attenuated Shope fibroma virus.