It is thought that it began as a mutation of the feline distemper virus. Once it had surfaced it caused a widespread epidemic which resulted in thousands of deaths among both wild and domestic canines. Parvovirus is seen considerably less since vaccination for the disease became available but outbreaks do still occur. Puppies between weaning age and 6 months old are the most susceptible to the virus. The disease is transmitted when dogs come in contact with the bodily fluids of infected animals.
Parvovirus is characterized by severe, bloody diarrhea and vomiting, high fever and lethargy.
The diarrhea is particularly foul smelling and is sometimes yellow in color. Parvo can also attack a dog's heart causing congestive heart failure. This complication can occur months or years after an apparent recovery from the intestinal form of the disease. Puppies who survive parvo infection usually remain somewhat un-healthy and weak for life. The surest way to avoid parvo infection in your dog is to adhere to the recommended vaccination schedule which begins when puppies are 6-8 weeks of age.