My neighbor has a cat that is foaming at the mouth but does not act sick at all. the only problem she has is the foam from the mouth.

My cat does this when he is really excited or when he feels really loved. If it is really foamy foam then I do not know but if it is more like bubbly saliva then go with your instinct about the cat. Cats hide pain and discomfort fairly well when they want to. Make sure he/she is drinking plenty of water. As far as rabies is concerned the cat would be extremely irritable and angry or moody not just foaming at the mouth. Also, yes rabies is highly contagious and even you can get it if he/she has rabies.

Cats will froth and foam when they have tasted something awful. Either she bit into something, licked something…. who knows what…that didn't taste good. Certain topical flea meds will cause this if she is able to groom the area where it was applied. Pilling a cat can certainly cause this.
Worst case scenario would be rabies – which is rare, but I guess still plausible. another not so great scenario would be a poisoning.

Yes this is the symptoms of rabies. asked him to meet his vet. And that can be catch by other animals also. It's a virus. Visit on agritura.com for various cat products.

My cat got absolutely terrified one time and started to foam at the mouth. As soon as the stimulus went away, she stopped foaming. she also kind of drools/foams when she is really happy and purring.

If they eat something that taste bad they will foam at the mouth. My cat did that when I put his flea medicine and it leaked where he could lick it. he did not like the taste at all.

rabies. Tell your neighbor to take her to the vet ASAP!!! Poor kitty.

rabies or the cat is very dehydrated

Kind of late, now, but maybe antifreeze?

i absalutly posatutly casapuly assure you that its rabies