It seems like every week a dog with Parvovirus infection will be seen at the Animal Medical Center  It is the most common infectious disease of dogs we see.  Young dogs, especially those that have not been adequately vaccinated, are the most common victims.

The virus is shed in the diarrhea of infected dogs and it is very resistant in the environment.  Indeed, it may be found for many months in the yard and homes of infected animals.

DIAGNOSIS

Young dogs that are listless and have had bouts of vomiting and diarrhea. 

Testing for the presence of Parvovirus in the stool is readily performed.

Also, patients ill with Parvo frequently have leukopenia (Low white blood cell count)  The severity of the leukopenia ofter indicates the severity of the infection.  Daily monitoring of the white cell count can help understand the stage of the disease. 

TREATMENT

Treatment for Parvovirus is largely based on supportive care.  Fluid replacement to counteract the dehydration is critical.

Antibiotics to counteract the effects of secondary bacterial invaders is also very important.

Medication to prevent vomiting can be helpful, especially if oral medications are being used.

More severe cases with accompanying low blood protein levels are managed with the help of Hetastarch and/or hyperimmune plasma.

The virus has to "run its course"  This can take from 2 to 9 days with most dogs showing improvement after 4 days.

VACCINATION

Puppies receive antibiodies that protect them from parvovirus  These antibodies are transferred from the mother to the puppies in the first 3 days of life.  Mother's first milk, colostrum, is the source of these antibodies.

How long the protection from mother will last is uncertain.  Some pups are no longer protected by mother as early as 6 weeks.  Some pups are protected by mother for 12 weeks.

At 6 weeks of age about half of puppies are no longer protected by "mom".  It is important that they be vaccinated so that they will be protected from Parvo.  However, if "mom" is still protecting the pup, the vaccination will be ineffective.  "First shots", "Temporary shots", "Puppy shots" are terms sometimes used to define this undetermined vaccine status.

At 9 weeks of age, 8 out of 10 pups need the vaccine and will respond to vaccination.  Alas, 2 out of 10 are still protected by maternal antibodies they received from "mom"       8 1/2 weeks earlier, and the shot will not work.

12 weeks of age represents the time when vaccine should work for nearly all puppies.  A booster in 3 weeks is a good idea.

In summary:  Vaccination prior to 12 weeks is a wise.  Two doses after 12 weeks of age is essential to insure a good immune response to vaccination.