What is Parvovirus?

Parvovirus is a new disease, appearing in 1978 and exploding around the world within a few months, infecting millions and killing thousands of dogs.  It is believed that parvo was created either from cats’ kidneys used for developing the distemper vaccine being infected with FPV or that cats that were vaccinated with FPV shed that vaccine and it mutated into canine parvovirus.

There are two canine parvoviruses, canine parvovirus-1 and canine parvovirus-2.  CPV-2 is the primary cause of the puppy enteritis that is commonly seen.  Over the years, parvo has mutated from CPV-2 to CPV-2a (late 1970s) to CPV-2b (mid 1980s) to CPV-2c (2000).  And CPV-2c is now crossing species and infecting cats with another brand new virus.

Parvovirus is a highly contagious viral disease that is transmitted by direct contact with infected dogs or indirectly through saliva or faecal contamination.  The virus is a very stable virus and can survive in the environment for many months and may also be spread by transfer on clothing or other objects.

There are two predominant clinical syndromes associated with parvovirus

Enteric form, Enteritis which is inflammation of the small intestine. This is most common in younger animals, especially puppies, although all ages of dog can be affected.  Clinical signs include vomiting, diarrhoea and marked depression, leading to blood stained diarrhoea and high temperature.  The cells that line the intestine are attacked and killed, so the dog cannot absorb fluids.  Puppies get dehydrated and die if not treated immediately.

Cardiac form, Myocarditis (inflammation of the heart muscle). This form of infection tends to occur in very young dogs when the heart muscle is still developing.  Clinical signs will vary but range from sudden death to typical signs associated with heart failure.

Cardiomyopathy did not affect dogs before the parvovirus outbreak or was very rare.  Since the parvo pandemic, cardiomyopathy is prevalent in many breeds.  It is believed that the parvovirus vaccination is likely to be the cause of most cases and that vaccination created the heart muscle association in parvo that is not seen in natural infections. 

Stats show that 28% of vaccinated puppies still get the disease. 

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