In this condition puppy will die shortly. Survival depend on type of virus and condition of disease. If dog infect Corona virus, it will spontaneous heal. But this is contrast in the case of Parvo virus. Dog should be taken to the veterinarian for supportive therapy.
Occurrence are less than gastroenteritis.
It is seen only in less than 2 months puppy, because the heart cell or myocardium of puppy still dividing. When puppy infect virus, it will stop suckling, and begin vomiting. Inflammation of the heart lead to damage its gross structure and cause heart failure. Corona virus doesn't do this. If bone marrow and lymph nodes are dysfunction, total white blood count in blood stream will decrease.