It is a viral disease that affects all warm-blooded animals (not just foxes and dogs).
The symptoms that occur in an affected cat are restlessness and drooling (excessive salivation), due to very strong and painful muscle cramps that prevent the cat from keeping its mouth open and drinking (hence the term "hydrophobia" ).
The situation in Italy
In Italy it is practically absent, so to avoid excessive alarmism it is good to remember that felines who have dental problems, gum inflammation, tonsils, jaws, poisonings always have symptoms similar to those of rabies, which however obviously have nothing to do see with this disease.