Giving a rabies shot to a cat that already has rabies does not cure it of rabies. Nor are rabies vaccines effective at all on the undeveloped immune systems of kittens. Google for: RABID KITTEN ADOPTED WAKE COUNTY (for just one example of hundreds adopted from outdoors, given their rabies shot, but still transmitting and then dying from rabies). The incubation period for rabies is, on average, from 21 to 240 days, sometimes up to 11 months, one rare case being 6 years. A vetted cat can STILL transmit rabies many months later (during the last 2 weeks before it dies of rabies, sometimes not even showing any symptoms up to the point of its death) if it was harvested from unknown rabies-exposure conditions with an unknown vaccination history. Either quarantine them for 6 or more months in a government-supervised double-walled enclosure system at their OWN expense (as required by national and international pet-trade, import/export, and animal-transport laws), or euthanize them.