Red eyes

Hello.
One of my cats has red eyes and fever. The vet has no idea about the disease that is causing it. He does not have other symptoms, but he seems to me very sick. I am so worried about him and the other cats. Can you please help me? Thank you.

When did the vet see your cat, and did they run any tests?  When did the symptoms start?

If you are really worried and feel unhappy about the vet you saw, if you have another vet in your area there is also no reason why you should not take your cat for a second opinion or change your vet if it helps find out what is happening.

If your cat is very hot and you are worried about this while trying to talk to a vet you can try to cool your cat by damping the fur down with a cloth:  the water evaporating helps to reduce the cat's temperature.

Thank you for your suggestion.

The symptoms started on Wednesday.

Unfortunately I can not take him to another vet because there only two vets in my area and both have no idea about this problem.
The vet said that he could take blood tests, but only on Monday. Meanwhile I think that the poor cat is getting blind.

Very hard when you are in an area where there is little choice and no out of hours access to help.  You are doing what you can with having already talked to your vet and continuing to ask the vet to check things out.  I hope your cat is OK until Monday when you can get back there again.

How old is your cat?  Does he go out, and any chance there could have been an injury to his head or eyes?  The more information you have ready for your vet on Monday the better as you never know what might give them a clue as to what is happening.  I very much hope for you that this is not some kind of infection and no risk to your other cats, like an injury or raised pressure in  his eyes or something, but just in case do check all your other cats for any signs of illness, and if it isn't too distressing try to keep them seperate.  

I am not sure what you are observing to make you think he is loosing his sight but if so, cats can accommodate to loss of sight very well but it is important to keep things like food and water in the same place and not move things around in the home while the cat gets used to new ways of orienting himself.  (They will use their whiskers a lot more and often walk close to walls and furniture so their whiskers get messages about where they are initially).