Parvovirus is a disease that primarily attacks the lining of the small intestine, bone marrow and in some cases can cause heart inflammation. All of these can lead to vomiting, diarrhoea, severe dehydration, shock and death, especially in puppies and partially vaccinated dogs.

Parvo in puppies is more common than in older dogs, although the disease affects them in the same way—by attacking their gastrointestinal system. Puppies are most susceptible to parvo between 6 to 20 weeks of age. During this window of time, your veterinarian will likely administer the parvo vaccine in a series of shots over several weeks.