Sounds like she has calici virus. It should be fairly mild if they are
vaccinated. Unfortunately there is nothing you can do unless you had separated
them at the first sign and changed your clothes with each visit to the sick
kitty's room. My cats have the virus go round everyso often, its usually
last a few days and rarely affects them, including the heart cats. But if
there is green or yellow discharge or breathing wheezy then go to the vets
for antibiotics as that's a secondary bacterial.
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