The most severe period of a dog’s parvovirus is from the third to the fifth day. This is the middle and late stage of parvovirus, and the condition will worsen. If the dog can survive it, it will begin to improve and recover. If it does not, it will Death may occur, so special attention is required. Parvo requires symptomatic treatment, including antivomiting, antidiarrhea, and hemostasis, as well as infusion to supplement nutrition and maintain physical strength, so that the cure rate is relatively high.