Canine hepatitis is a viral disease that can affect dogs worldwide, causing inflammation of the liver and potentially impacting other organs. Understanding this condition is important for dog owners, as it can range from mild illness to severe, life-threatening cases. Awareness of the disease, its signs, and prevention methods can help ensure pet well-being.
What is Canine Hepatitis?
Canine hepatitis is an infectious disease primarily targeting a dog’s liver, though it can also affect the kidneys, spleen, lungs, and the lining of blood vessels. It is caused by the canine adenovirus type 1 (CAV-1), a virus distinct from human hepatitis viruses. This virus is highly contagious among canids, including foxes, wolves, coyotes, and bears.
Transmission of CAV-1 occurs through direct contact with infected bodily fluids such as urine, feces, saliva, and nasal or eye discharge. The virus can also survive in the environment for weeks or months on surfaces, allowing for indirect transmission. Young, unvaccinated puppies are most susceptible to severe forms of the disease, though dogs of all ages can be affected. Dogs that recover from the infection may continue to shed the virus in their urine for up to a year, posing a risk to other animals.
Recognizing the Symptoms
The symptoms of canine hepatitis can vary widely in severity, from mild to fatal outcomes. An initial sign often includes a fever, which can exceed 104°F (40°C) and may last for one to six days, sometimes occurring in two stages. Dogs may also exhibit general signs of illness such as lethargy, a decreased appetite, increased thirst, and depression.
More specific signs related to organ involvement can develop as the disease progresses. These include vomiting, diarrhea (which may contain blood), and abdominal pain. Jaundice, characterized by a yellowing of the gums, skin, or eyes, can also be observed due to liver dysfunction. Fluid accumulation in the abdomen, known as ascites, can occur in more severe cases.
Eye symptoms include inflammation, watery discharge, or corneal opacity (commonly known as “blue eye”), which causes cloudiness of one or both corneas. Bleeding disorders are also a concern, potentially leading to spontaneous bleeding, bruising, or hemorrhages in the mouth. In severe instances, particularly in young puppies, the disease can progress rapidly, leading to circulatory collapse, coma, and death within 24 to 48 hours.
How Canine Hepatitis is Diagnosed and Treated
Diagnosing canine hepatitis begins with a thorough physical examination and a review of the dog’s clinical signs. Blood tests are a next step, including a complete blood count (CBC) to check for a low white blood cell count, which is often seen during the feverish period. A biochemistry panel is also performed to assess liver enzymes, as elevated levels can indicate liver damage.
Further diagnostic steps may include specific viral tests like ELISA, PCR assays, or serologic evaluation to detect the presence of the virus or antibodies against it. Sometimes, imaging techniques such as ultrasound may be used to assess the liver and other internal organs. A definitive diagnosis, especially for chronic forms, might involve a liver biopsy to examine tissue changes and assess copper levels, which can contribute to liver injury.
Treatment for canine hepatitis is primarily supportive, as there is no antiviral cure for CAV-1. Treatment focuses on managing symptoms and supporting the dog’s bodily functions to allow their immune system to fight the infection. This often involves intravenous fluid therapy to combat dehydration and maintain electrolyte balance, particularly if the dog is experiencing vomiting or diarrhea.
Medications may be administered to control symptoms such as vomiting, pain, or secondary bacterial infections. Nutritional support and liver support supplements may also be provided to aid liver recovery. In severe cases, blood transfusions may be necessary to address blood loss or clotting abnormalities.
Protecting Your Dog Through Prevention
Vaccination is the most effective method for preventing canine hepatitis. The vaccine for canine adenovirus type 1 (CAV-1) is a core vaccine, recommended for all dogs. It is frequently included in combination vaccines such as DHPP or DAPP, also protecting against distemper, parvovirus, and parainfluenza. While the vaccine targets CAV-1, many modern vaccines use a modified live canine adenovirus type 2 (CAV-2) strain, which provides cross-protection against CAV-1 and is less likely to cause side effects like “blue eye” or be shed in urine.
Following a veterinarian-recommended vaccination schedule is important, especially for puppies. Puppies typically begin vaccinations between 6 and 8 weeks of age, with initial hepatitis vaccine doses administered around 7 to 9 weeks, followed by a booster between 11 and 13 weeks. Maternal antibodies from the mother can interfere with a puppy’s immune response to vaccination until they are 9 to 12 weeks old, influencing the timing of these shots. Regular booster shots throughout a dog’s life are necessary to maintain protection against this condition.
Beyond vaccination, general hygiene practices can reduce transmission risk. These include promptly cleaning up after pets and disinfecting areas where infected animals may have been present, as the virus can persist in the environment. Avoiding contact with potentially infected animals, especially if they show signs of illness, is another precaution to protect your dog.