what I learned about "kitty-colds"
My foster kittens had sore eyes (red and crusty, with the third eyelid showing) and sneezy noses, and the shelter had me treat them with antibiotic ointments and oral medications. I understand that it helps kittens get over these things, even though they are viral and an antibiotic doesn't treat viruses. It may lessen the illness or shorten it in a kitten. They were still sick for five weeks, though, so maybe it didn't shorten anything, just prevented it from being more serious. The last eyedrop we finally tried was an anti-viral and that seems to be what cleared it up.
A few weeks into this, my adult cat caught it and he, too developed sore eyes, and later a little sneezing and coughing. I treated him with some of the same antibiotic ointments and he still had the sore eyes after two weeks. So we paid a visit to the vet today. He has been lower in energy than usual, sleeping on my lap more and playing less, but still eating and otherwise normal.
Well, the vet said that since it is a virus we just need to wait it out. It can take several weeks, unlike one of our human colds that usually lasts ten days or so. So not to worry, his temperature was normal and no secondary infection. If he does get worse and stops eating, then that would be time to try an antibiotic because then it would be very likely that there was a secondary infection.
So now I know that if a healthy young adult cat gets one of these things, but still is eating and acting more or less normal, that you really don't need to do anything but wait it out. It's different than for a young kitten, and different from a human cold which doesn't last that long. I asked her how long it should last and she said, "As long as it takes."
She also said there is little you can do to prevent the germs going everywhere, and that it is "in the air". Maybe a strict quarantine in one room would have prevented it. But my kitty loves kittens and plays with them like he is one of their brothers, wrestling and napping with them-- it's easy to see how he got sick! I didn't know eye infections were that contagious.
I'm hoping this information will save some of you a needless trip to the vet! Next time I will know to do differently.
Here's Eddie with one of "his" kittens:
= new reply since forum marked as read
It did take five weeks in my foster care though. They've all gone back and are already all adopted! The two boys together, and the one female got adopted with another female kitten. I'm always delighted when I hear that my kittens have gotten adopted in pairs. 
what I had assumed was my cat taking too long to cough up a hairball was actually a respiratory ailment, which was cleared up in a couple days by a shot. 
