Congrats to your friend.I think that if a cat has a low immune system then they'd be more likely to get them. Also if a cat has the herpes eye condition, I think that this could progress into a URI if it's not treated early but I could be wrong. A vet once told me that all kittens have low immune systems and they're much more prone to get URI's and other illnesses than adult cats.
Here's a good link about URI's in shelter cats: http://www.thecatsite.com/Health/92/...ue-Groups.html.
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