Infectious canine hepatitis is a disease involving the inflammation of the liver in dogs and is caused by a virus known as the canine adenovirus type 1 (CAV-1). Animals other than dogs can be affected such as wolves and coyotes. Death can occur as a result of infection canine hepatitis within as little as two hours without the owner having had any knowledge that the dog had been infected and so is considered a serious and fatal disease. When this does come to pass some owners often ask for biopsies since, although not the case, it may appear as though dog had been poisoned. The virus increases its numbers in the tonsils and then spreads to the kidneys and the liver. Dogs under the age of one year old are more susceptible to contracting the disease due to a weaker immune system than older dogs although unvaccinated dogs at any age are prone to catching it. Dogs can recover and those that do can obtain a blue tinge to their eyes for a short period of time although vaccination is strongly encouraged and advised by veterinarians to prevent this highly contagious disease from spreading.
The canine adenovirus type 1 is transmitted orally from the spread of bodily fluids such as urine, blood, nasal discharge, and saliva. It can also be spread by faeces and contaminated items such as clothing and food bowls. Organisms which bite the animal such as fleas and mites can also infect the dog by inoculating the disease into the blood. Even if the dog does recover it can still spread the virus for as long as even one year through defecation.
If a dog has had the virus and has contaminated the household then disinfectants containing strong ammonium compounds should be used. Steam cleaning is also relatively effective. Neither of these, of course, should be used on the dog itself. It is very important to do this because the virus can survive for long periods of time away from the dog.
The known symptoms following the contraction of infectious canine hepatitis includes a sore throat which results in coughing. This is accompanied by depression, lethargy, and loss of appetite. A high temperature can also be noticed and the abdomen becomes very sore. Some dogs experience seizures or convulsions. As the canine adenovirus type 1 spreads to the liver, jaundice and vomiting occur along with diarrhoea or sometimes even constipation. Jaundice presents itself as a yellowish colouration of the skin as the dog begins to experience liver failure and the dog’s stool may sometimes be a very pale in contrast to its usual brown appearance.
In some rare cases, severe bleeding can be seen as a result of the infection. It is generally this bleeding, or liver and kidney failure, which results in the fatality of the disease. Before this occurs the dogs may be able to fight the disease by itself but even so the veterinarian should be contacted as soon as any symptoms are presented. Following recovery, the dog will retain a blue colouration on the retina for some time. The medical term for the “blue eye” is chronic corneal oedema
Treatment and Prevention
There is no cure for infectious canine hepatitis. There is no specific treatment plan but usually it involves treating the symptoms. An IV is administered in the veterinary practice to replace lost fluid and antibiotics are given to prevent any secondary infection which may occur. The dog must be allowed to fight the disease by itself due to the lack of cure and so all that can be done is to give support; keeping the dog as relatively healthy as possible to give it the best possible chance of survival.
Due to the fact that there is no cure it is highly recommended that all dog owners have their pets vaccinated against canine adenovirus and fortunately many responsible dog owners across the UK do so. Boosters are then required to be administered annually to maintain long term immunity against the virus. In vaccinating their dogs, owners not only protect them from infection but also other dogs which may not be vaccinated. Overall this prevents the spread of the disease.
Diagnosis and Prognosis
Canine hepatitis is diagnosed by observing the virus under a microscope through obtaining the infected faeces, urine, blood, or nasal discharge. Before this test is done in the laboratory, the veterinarian usually makes a mental possible diagnosis by looking at the symptoms presented. The laboratory work then acts as a confirmation as to what the disease is. In mild cases of the disease, dogs often do survive although fatalities occur as the disease becomes more severe.