Canine Adenovirus 1

Causes Infectious Canine Hepatitis

Hosts

• Dogs
• Foxes are very susceptible (Fox Encephalitis)

Pathogenesis

• Infects and replicates in the oropharynx
• Viremia as the virus reaches endothelial cells
• Attacks the endothelial lining of gall bladder, liver sinusoids, and Kuppfer cells
• Resulting heptatitis is followed by severe abdominal pain and often death
• Post Mortem: swollen, hemorrhagic liver, ascites, and oedema of the gall bladder
• In older dogs, may present more mildly with lymph node enlargement and chronic interstitial nephritis
• In foxes: virus replicates in the endothelia of the brain resulting in neuronal damage, fits, and paralysis

Epidemiology

• Transfers easily via ingesting infected urine, feces or respiratory secretions
• Can be transferred by handlers, infected surfaces, etc.

Diagnosis

• Intranuclear inclusion bodies in hepatocytes can be seen under H&E staining
• Vascular endothelium can be stained for viral antigen by immunofluorescence

Control

In an outbreak

• Isolate infected dogs
• Disinfect premises

To prevent

• Vaccination: tissue culture adaptation that may be live or inactivated
• Cross protection with CAV2
• Live vaccines are known to cause keratitis in Afghans, Red Setters and Saluki

Adenovirus pneumonia (Image sourced from Bristol Biomed Image Archive with permission)

• Adenoviridae
• Usually mild bronchointerstitial pneumonia, necrosis of bronchiolar and alveolar epithelium, oedema, type II pneumocyte hyperplasia
• May cause necrotising bronchiolitis in immune-deficient dogs (distemper)
• Can be associated with kennel cough described above