Infectious Canine Hepatitis

The Virus classification
Group:	Group I (dsDNA)
Family:	Adenoviridae
Genus:	Mastadenovirus
Species:	Canine adenovirus 1 (CAV-1)

This plague is an acute liver infection in dogs brought about by canine adenovirus type-1 (CAV-1). CAV-1 also causes severe health disorder in wolves, coyotes, and bears, and encephalitis in foxes and mongrels. The virus is disseminated in the saliva, nasal discharge, blood, urine and faeces of infected dogs. It is contracted via the nose or mouth, where it reproduces in the tonsils. The virus then infects the liver and kidneys. In most cases, the course of incubation is 4 to 7 days.

The symptoms associated with the disease are increase in body temperature, weakness, depression, anorexia(loss of appetite), coughing, weight loss and a tender abdomen. Corneal edema and signs of liver disease, such as jaundice, emesis, and hepatic encephalopathy, may also occur. Severe cases will progress to bleeding conditions, which can cause hematomas to form in the mouth. Death can occur secondary to this or the liver disorder. After all, most dogs recover after a brief illness, although chronic corneal edema and kidney lesions may remain.

The diagnosis is made by observing the blending of symptoms and abnormal blood tests that occur in infectious canine hepatitis. An increasing antibody titer to CAV-1 is also seen. The disease can be confused with canine parvovirus due to the fact that both will result in low white blood cell count and bloody diarrhea in young, unvaccinated dogs.

The treatment for such a disease is characteristic. Most dogs recover immediately without treatment. Prevention is through vaccination (ATCvet code QI07AA05 (WHO) and different combination vaccines). Most combination vaccines for dogs consist of a mutated canine adenovirus type-2. CAV-2 is one of the agents of respiratory disease virus in dogs, but it is similar enough to CAV-1 that vaccine for one establishes immunity for both. CAV-2 vaccine is much less likely to cause side effects than CAV-1 vaccine. A particular study has demonstrated the vaccine to have a duration of immunity of more than four years.

The virus, CAV-1 is destroyed in the environment by steam sterilization and quaternary ammonium compounds. If not, the virus can survive in the environment for months in the right conditions. It can also be discharged in the urine of a recuperated dog for up to a year.