Prognosis
Cats that develop feline parvovirus become very sick; there is a 50 to 90 percent chance that affected kittens will die from the illness because of their immature immune systems. Also, adult cats with weak immune systems do not have a good prospect of surviving. Healthy animals, however, are often able to fight the illness and their symptoms tend to be less severe. If a cat survives the disease, it is immune to reinfection for life.