Small vomiting of blood by a puppy can only mean that there is bleeding in the puppy's body, and timely hemostatic treatment is required. After parvovirus enters the puppy's body, it will destroy intestinal cells and cardiomyocytes. If intestinal bleeding occurs, blood will flow backward and enter the stomach, causing vomiting of blood. If the myocardial cells are damaged, you need to consult a pet doctor for treatment as soon as possible, otherwise it may cause the puppy's heart failure, and in severe cases, death.