My cat brought me a mouse... advice?

Question
Yesterday my cat brought me a mouse, it has a limp and possibly what seems to be a minor scratch on its side. The scratch I think isn't serious because it doesn't seem to be causing the mouse pain, but he is limping and I didn't want to put him back out into the cold and rain. The problem is I had to leave home for two days and two nights, the last time I saw him was this morning and I gave him a small mountain of carrots and halved and whole grapes, and a lot of water. Do you think he'll be okay? I know I shouldn't have left him but I had no choice :(
So I could possibly go home tomorrow to check up on him but it would be pretty difficult... Did I do the right thing? He doesn't seem to be dizzy or anything, he doesn't walk into things or fall over, but with his leg hurt I figured I should keep him until he could walk well enough. If I get back and he's dead I'll be really sad :(
But I hope he isn't... I made sure he had some water before I left, I used a straw and he actually drank from it with a bit of patience on my part. I really would like to make him better, but I haven't any experience with mice at all. So here's my plan so far: when I get back I make sure he's eating and drinking, I make sure he isn't too lethargic, I use a Q-tip to put some polysporin on his side and leg to prevent an infection and I keep him nice and warm.
So far he's in a box lined with paper towel, he has some kleenex for lack of anything cozy and a half of a toilet paper roll- his favorite. He has a corner for his food and water and that's about it. I don't even know what type of mouse he is, he has a grey-brown coat on the top and he's white on his belly, I forget the colour of his tail. He's about an inch and a half long when balled up and 2 inches long when he walks. I don't know, is he a baby? He has all his fur. So any advice would be good, like what food is best, safe toys, signs to look for in case of illness, are there any diseases I can catch (I'm very carful, I don't handle him- mostly because I'm afraid I'll hurt him, and I always wash my hands...) how would I go about moving him without hurting him, how can I tell if he's even a he? And please tell me if I'm doing anything wrong so far.

Thanks in advance,

Emily.

Answer
He's a very lucky mouse! It is very rare for mice to survive after a cat attack. They either die of shock or poisoning from the bacteria in the cats mouth.

He is also lucky to be looked after! You did the right thing. If you had released him when hes not 100% he would have either starved to death or caught by a predator.

If he is dead, it won't be your fault. You gave him luxury mouse food (how many wild mice have a chance to eat yummy grapes?) and a warm place to sleep. If he has passed away his last hours were very comforting.

If he has managed to survive the best thing to do is to nurse him back to health and then release him back into the wild.

I could give you an accurate answer regarding his breed and age with a photos. I can determine his sex if you send me a picture of his bottom with his tail lifted. You may have a deer mouse if his eyes are quite large and round.

Depending on where you live he may have a disease called Hantavirus. Although this is quite rare, it is best to check either on the internet or with your vet.

Mouse or hamster mix is the best thing to feed him. It contains all the vitamins he needs and its inexpensive. Toilet tubes, wheels, ladders and boxes make great toys. Make sure they are non- toxic to mice. Make sure you keep him in a plastic or glass tank with a secure lid (chicken mesh is great) or a cage made specially for mice. Mice are fantastic escape artists and can gnaw through cardboard and squeeze through tiny gaps.

Wild mice are difficult to handle and may bite but if you need to make sure you keep a firm grip of his tail. If you need to move him you can lift him by the tail. Make sure you  gently pinch a third of the way down his tail and never at the base or tip. Only do this for very short periods of time.

Please feel free to ask any more questions. Good luck!