Parvovirus in Dogs

Canine parvovirus is a common viral infection in dogs. CPV is a medical emergency and prognosis improves with rapid, aggressive treatment.

Most cases of CPV require a long period of hospitalization. Treatment is often expensive due to the length of hospitalization. Some mild cases can be managed at home with regular vet visits. At least 10% of cases are fatal, even with proper treatment. 90% of untreated cases are fatal.

CPV is a resilient virus that is able to survive in the environment for over a year and is resistant to heat, cold, and drought. The virus can be spread on objects such as shoes, clothing, fur, and grass. Dogs do not need to be in direct contact with another infected dog to contract CPV. Any surfaces or environments an infected dog has contacted require thorough cleaning with bleach.

Symptoms of CPV usually appear 4-6 days after exposure. Many cases of parvovirus affect breeding kennels, leading to several littermates showing symptoms within a short time frame. In severe cases, or in very young puppies, CPV can present as sudden death overnight.

It is important not to introduce puppies into houses which have had CPV for at least a year. Even fully vaccinated puppies are at risk until they are adults, as dogs have a variable response to vaccination, particularly in the first year of life. Fully vaccinated adult dogs are the safest option to introduce into previously exposed households to reduce the risk of CPV.

CPV is the result of a viral infection that targets the cells of the gastrointestinal system. The virus is highly contagious and is primarily spread through fecal-oral transmission.

Diagnosis of CPV involves:

• Clinical history
• Physical examination
• Fecal antigen test for the virus
• Blood tests
• Diagnostic imaging such as ultrasound and X-rays

Treatment of CPV is intensive, and involves:

• Hospitalization
• Supportive care including IV fluids, anti-nausea medications, and antibiotics to prevent secondary infections
• Nutritional supplementation through IV fluids or a nasal feeding tube
• Antiviral therapy may be trialed in some cases

Dogs with parvovirus must be strictly quarantined away from all other dogs, to prevent spread of this highly contagious pathogen.

Symptoms of CPV last for up to 10 days. Most cases of parvovirus fatality occur within the first five days. Dogs that survive the first five days of the infection are more likely to recover completely.

Prevention of CPV focuses on vaccination. Effective vaccination requires administration by a veterinarian at 6, 9, and 12 weeks of age. Vaccination does not offer guaranteed protection, so strict quarantine of infected dogs and thorough environmental cleaning is recommended.

Environmental prevention is important as CPV is able to survive in the environment for over a year. Preventive measures aim to reduce contact between young dogs and areas where CPV is commonly found until the primary vaccination course is complete.

• Keep puppies off the ground and away from other dogs
• Avoid areas where other dogs gather such as groomers, kennels, and puppy classes
• Prevent contact with dogs known to have CPV

Confirmation of CPV on a premises requires effective sanitization to prevent reinfection. CPV survives on surfaces and is particularly resilient in dark, moist environments. Sanitization involves:

• Removal of organic material, such as feces, from areas such as bedding, grass, dog fur, and hard surfaces
• Once visibly clean, surfaces and textiles are disinfected using appropriate disinfectants such as bleach.
• Dilution of disinfectants must be at the specified concentration and should be rinsed off after the appropriate amount of time

The prevalence of CPV varies between regions, but is common everywhere. Clinical disease is more common in areas where parvovirus vaccination rates are low.

• Fluid therapy
• Medication to reduce vomiting and diarrhea
• Medication to prevent secondary bacterial infections
• Hospitalization
• Quarantine
• Antiviral treatment