What is Canine parvovirus and how it can affect your dog and be treated in Ohio
Canine parvovirus is a disease affecting young dogs; higher numbers of infections are seen in the spring due to an increased number of susceptible puppies and an increased risk of exposure to the virus. Parvovirus is hardly in the environment and is difficult to kill with standard disinfection methods. It is shed in huge numbers (billions of virus particles in each bowel movement) by infected animals, is resistant to freezing and most household disinfectants, and is carried by shoes and clothing. The virus is ubiquitous in the environment, meaning that it is present EVERYWHERE. Attempting to shield a puppy from exposure is futile; the only successful method of protection is vaccination. Parvovirus enters the body through the mouth. There is a three- to 14-day incubation period during which the puppy does not show signs of illness, but is shedding the virus in large numbers in the environment. The virus is especially effective at infecting rapidly dividing host cells, including the cells of the lymphatic system, the bone marrow and the gastrointestinal tract. The virus replicates in the lymph nodes, causes significant decreases in white blood cell counts in the bone marrow, and invades the intestinal cells, leading to vomiting, diarrhea with blood, and bacterial leakage into the body. The patient may then die rapidly from dehydration, shock and septic toxin spread into the bloodstream. A diagnosis of parvovirus can be made via a stool sample test, suggestive symptoms of the disease or a decreased white blood cell count on lab testing, and blood titer testing. Treatment focuses on supportive care. There are no antiviral drugs available, so we must rely on the patient’s immune system to clear the virus. Owners must be prepared for a three- to seven-day hospital stay, intensive care, and significant expense to treat a patient with parvovirus. If this is possible, an 80 percent treatment success rate can be achieved. Treatment includes intravenous fluids, electrolytes, injectable antibiotics and anti-nausea medications, in addition to monitoring hydration, blood cell counts and protein levels. Plasma transfusions may be indicated in severe infections. As the patient improves, oral medications and specialized dietary therapy are needed. Disinfection of the environment following a parvovirus infection is very important. The patient may continue to shed the virus for weeks following resolution of symptoms. Indoor hard surfaces, bedding and clothing should be cleaned with a solution of one part bleach to 30 parts water — again, household disinfectants other than bleach do not kill the virus. The solution should be left on the surfaces for a minimum of 10 minutes. Steam cleaning will kill the virus, as well. Outdoors, the virus is preserved by freezing, so owners should wait at least 1 year prior to obtaining a new puppy. Parvovirus infections are seen nearly exclusively in puppies and adolescent dogs. Puppies have no antibodies with which to fight disease when they are born, except for those obtained from nursing on their mother’s colostrum during the first few days of life. (If the puppies mother is not currently vaccinated for parvo virus, the puppies will have no immunity.) These antibodies wear off during the first three- four months, until the puppy is no longer protected against disease.
This is why veterinarians recommend vaccinating puppies every two to four weeks until they are 16 weeks of age — a time when we know the maternal antibodies have decreased and a vaccination will be effective. Giving vaccinations more often than every two to four weeks will cause interference between the vaccines. Please speak with your veterinarian if you have any questions or concerns about parvovirus in your dog. Above all, don’t wait, vaccinate your puppy against this deadly disease to keep it safe and healthy.