Canine hepacivirus

From Dog
Prototype HCV species and suggested species within the genus Hepacivirus of the Flaviviridae family of viruses and their natural and experimental hosts.[1]

Canine hepacivirus (CHV) is a flavivirus associated with respiratory disease.

This virus is closely related to human hepatitis C virus. At present, there are no definitive data on target organs in dogs or disease association of this virus with other species, including humans. Infections in dogs correlate directly with viral PCR detection in both the lung and liver[2].

Clinical signs are usually related to non-specific respiratory disease which may appear similar to symptoms associated with infectious tracheobronchitis (kennel cough). Hepatitis, though rare, may also occur.

Long-term consequences of hepacivirus infectious such as hepatic carcinoma (as is observed with human hepatitis C infection) have not been reported in dogs, although CHV has a strong affinity for hepatocytes and remains in the liver for some time after infection[3]. Unlike humans, dogs have active involvement of the tumor suppressor gene TGFbeta-r which appears to prevent the development of hepatic carcinoma, a gene inactive in humans patients with Hepatitis C-induced hepatocarcinoma[4].

Diagnosis is based on presenting clinical signs, exclusion of other causes of respiratory disease and identification of virus in tissue samples using immunohistochemistry or PCR assays[5].

A differential diagnosis would include other causes of hepatitis or kennel cough.

There is no specific treatment recommended for this infection although supportive therapy is indicated, including broad-spectrum antimicrobials to minimize secondary bacterial involvement.

References

  1. Bukh J (2011) Hepatitis C homolog in dogs with respiratory illness. Proc Natl Acad Sci U S A 108(31):12563-12564
  2. Kapoor A et al (2011) Characterization of a canine homolog of hepatitis C virus. Proc Natl Acad Sci USA 108:11608–11613
  3. Kapoor A et al (2011) Characterization of a canine homolog of hepatitis C virus. Proc Natl Acad Sci U S A 108(28):11608-11613
  4. Grabarević Z et al (2009) Comparative analysis of hepatocellular carcinoma in men and dogs. Coll Antropol 33(3):811-814
  5. Evermann J et al (2011) Thoughts on detection of hepatitis C virus in dogs. J Am Vet Med Assoc 239(9):1179-1180