Cat flu cause a runny nose and eyes, and a sore throat, mouth ulcers. Cat flu is not usually serious in adult cats, However it can be serious, even fatal, in kittens, and in adult cats with other serious underlying illnesses.
Eye ulcers are often found and, particularly in kittens, can progress to cause serious damage and even lead to the loss of an eye. If your cat or kitten has a sore looking or partially closed eye seek immediate veterinary attention.
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