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How to treat feline panleukopenia (distemper )
Keep an eye out for a high fever.
The incubation period from being in contact with the virus to developing clinical signs is approximately four to five days. The first symptom to develop is a high fever, which can occur so suddenly that the owner suspects their cat has been poisoned.
In adult cats that have a strong immune system or are vaccinated, they may contact the virus but keep it in check and not become ill. Watch for vomiting and bloody diarrhea to start.