Panleukopenia (Feline Distemper) or Feline Typhoid
A high fever is usually the first symptom of this disease which is often deadly and strikes quickly and unexpectedly. The virus will very rapidly attack bone marrow cells, the digestive system, the intestines and the nervous system. Symptoms will give your cat an amorphous behaviour, depression, loss of appetite, diarrhea, vomiting and a need to drink while being incapable of doing so. Rapid dehydration is followed by a coma, then followed by death.
Due to the brief incubation period of the disease, and the speed at which it progresses, death can come suddenly; two to three days, or even sometimes as few as 24 hours after the first instance of vomiting. The disease if very contagious and can be transmitted through excrement, urine, and from mother cat to kitten. It is responsible for a high mortality rate, especially when it is contracted by kittens. If the cat is lucky enough to survive the symptoms, the animal will usually survive, but a complete healing period may take up to a couple weeks. It is fatal in kittens who have not received their vaccinations.