A teenager pets a stray cat often who has been in fights then touches the faucet to wash his hands. faucet isnt cleaned afterwards. is there any risk of catching anything since i regularly use this sink. i use my hands to gargle?

I'd like to know how public health members would answer this question, but I don't think pathogens would survive very long on faucet handles. However there are many instances of pathogenic organisms contaminating water within certain faucets, especially those electronic ones without handles. Nevertheless wash your hands thoroughly after using the faucet after your friend uses it.