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Infectious Diseases

Also known as Parvovirus enteritis, it is a severe and deadly infectious disease that affects unvaccinated or under-vaccinated young dogs usually between the age of 6 weeks and 6 months, although it can also affect older dogs.

Parvo was first reported in the late 1970s, and within two years it was reported worldwide. There are multiple strains of parvovirus. Today the strain of parvovirus that causes Parvo in the United States is Canine ParvoVirus type 2b or CPV2b. This strain is different from the original virus. Canine Parvovirus has also been isolated in other canines such as raccoons, foxes, wolves, and coyotes.

How do dogs get Parvo?

Most dogs come in contact with the virus in the environment. The virus is shed in the stool of the infected dog. Any nonimmune, or under-immunized dog that comes in contact with a contaminated surface will become infected with the virus. The severity of the infection will depend on how much virus the dog is exposed to and the dog’s immune status. There is an incubation period which is the period from when the animal contacts the virus to when the signs of infection occur. This can vary from 4 to 14 days.

What are the signs of Parvo infection?

Parvovirus is the most common cause of infectious diarrhea in dogs under 6 months of age, although it can infect any dog of any age, breed, or sex. Pit bulls, German Shepherds, Rottweilers, Labradors, and Alaskan sled dogs seem to have increased risk. The signs of infection are vomiting, diarrhea, lethargy, decreased appetite, and rapid onset of dehydration. The most severe infections occur in pups that are less than 12 weeks of age. The virus is highly contagious and often fatal.

How is Parvovirus treated?

Early diagnosis and treatment are essential for possible recovery. There is a quick test for Parvo which gives results within 10 minutes. Treatment consists of iv fluids, anti-vomiting and antidiarrheal medications, antibiotics for secondary bacterial infections, and early nutritional support. Most cases require intensive 24-hour-a-day care for several days.

Treating parvo is very expensive, so early and complete vaccinations are advised to prevent this devastating disease. Vaccines are typically given at 6, 9, and 12 weeks of age. Additional vaccinations can be done at 15 to 16 weeks especially in breeds that are at an increased risk for Parvovirus infection.

Sylvia Graham, DVM

Staff Veterinarian NPVEC