Parvovirus (parvo)
A highly contagious, often fatal viral disease of puppies. Causes severe bloody diarrhoea and vomiting. Preventable by vaccination.
Canine parvovirus is one of the most feared infectious diseases in puppies. The virus attacks rapidly dividing cells — particularly the intestinal lining and bone marrow — causing severe bloody diarrhoea, vomiting, dehydration, immune suppression, and often death.
Most cases occur in puppies between 6 weeks and 6 months — after maternal antibodies wane but before the full vaccination series is complete. This is why vets stress that unvaccinated puppies should not visit public dog spaces.
Signs come on suddenly: profound lethargy, vomiting, watery or bloody diarrhoea, refusal of food, sometimes fever. Without treatment, death usually follows in 48–72 hours. With aggressive treatment (hospitalisation, IV fluids, anti-nausea, antibiotics, plasma, sometimes monoclonal antibody therapy), survival rates are 70–90%.
Prevention is straightforward: puppy vaccinations at 6–8, 10–12, and 14–16 weeks; titer check or booster at 1 year; periodic boosters thereafter. Until 2 weeks after the final puppy vaccine, avoid public dog spaces.
Parvovirus is extremely environmentally hardy — surviving months on surfaces. Outbreaks recur in places where vaccination compliance drops.