How Infectious Hepatitis Affects Dogs
It is difficult to really say how a dog infected with the canine adenovirus-type 1 “feels” or is affected by the infection. However, in light of the observable signs of severe acute infections, it is safe to say that this can be an extremely serious and potentially lethal disease - one that is capable of causing a dog to suffer a great deal of distress, discomfort and pain, which may or may not be noticed by its owner.
Symptoms of Infectious Hepatitis
Some dogs with infectious canine hepatitis (ICH) develop very mild infections and show no or few outward signs of illness. This is called a “subclinical” infection. In cases where symptoms do develop (clinical infection), the disease typically follows a fairly standard course. The first phase is called the “acute viremic stage”. During the acute viremic stage, infected dogs can rapidly become listless and develop progressive paralysis, seizures, collapse, coma, and ultimately death. This can happen within a matter of a few hours and can look very much like a case of poisoning. If they survive this initial stage, dogs with clinical ICH may develop one or more of the following signs:
- Fever (often very high)
- Excessive tearing and squinting (from sensitivity to light)
- Vomiting (vomitus is often bloody)
- Diarrhea (often bloody)
- Abdominal pain and tenderness (due to swollen liver)
- Tucked-up belly (from pain)
- Lack of appetite (inappetence; anorexia)
- General malaise (lethargy, weakness)
- Jaundice (yellow skin, mucous membranes, whites of the eyes [sclera] and feces; also called “icterus”)
- Enlarged liver (hepatomegaly)
- Enlarged lymph nodes (lymphadenopathy)
- Nose bleeds (epistaxis)
- Abnormal skin bruising
- Spontaneous bleeding from mucous membranes (especially the gums)
- Elevated heart rate (tachycardia)
- Rapid breathing (tachypnea)
One of the hallmarks of infectious canine hepatitis is a condition known as “hepatitis blue eye.” Blue eye is a clouding of the cornea caused by corneal edema and anterior uveitis. Corneal edema is an abnormal accumulation of fluid in the spaces between the cells of the cornea. Anterior uveitis is inflammation of certain structures within the eye. In most cases, this corneal cloudiness will go away within about a week.
Chronic hepatitis is occasionally seen after a dog recovers from infectious hepatitis.
Dogs at Increased Risk
ICH is most commonly seen in young dogs of less than 1 year of age and is largely a disease of puppies. However, dogs of any age, including older dogs, can become infected, especially if they have not been vaccinated against the infective canine adenovirus. There is no gender or breed predisposition to developing infectious canine hepatitis.