Canine parvovirus causes severe, painful gastrointestinal disease with high mortality in unvaccinated puppies. Prevention through vaccination is straightforward and highly effective.
Parvovirus causes extreme suffering -- intense abdominal pain, profuse hemorrhagic diarrhea, vomiting, and rapid deterioration to shock and death without treatment. Affected puppies are acutely ill within days and deteriorate rapidly. Intensive care treatment including IV fluid therapy, antiemetics, antibiotics, and nutritional support is expensive and requires days of hospitalization. The welfare case for vaccination is overwhelming -- it is the single most effective welfare intervention for dogs against this disease. Outbreaks in poorly vaccinated communities cause preventable deaths across many individual animals.