Is sneezing kitten contagious? How Long?

I have a 10 week old kitten that sneezes a few times a day. He was with his littermates at the vet last Thursday for a health check and a littermate ended up with an URI (picked up from the vet's office). The sick cat has since gone home to her new family and my guy only sneezes a few times a day and otherwise seems absolutely fine. I have three other cats, and would like to be able to introduce this little guy as soon as possible, but don't want to expose them to a virus.

What's the protocol here? Do I need to keep him isolated? And for how long?

Thanks for any input!

Well, my advice would be to call your vet - better to nip something early. I am not an expert, but I do know that colds and URI's are contagious and kittens, because they are smaller, can be infected quite easily.

I agree...call the vet.

After you do that, I would keep him isolated as long as he's still sneezing...unless by some odd chance it's just something in "the air" that's irritating him. Given his age and the recent events, I would guess he has a little cold/URI.