Yuck!! Cleaning up after mice

Well a day that started great is going to end in gross cleaning.

I sold my minivan yesterday afternoon and so hauled everything out and put my kids 3 carseats and my little box of "stuff" that I always keep in the vehicle. Hubby's truck has spare booster seats and I drove it until this afternoon when I picked up my new van. I parked my van down by the barn ready to load my carseats into it before collecting kids from school. Instead I found they are covered (and I mean covered!) in mouse poo Gag.

Now I'm going to have to try and figure out how to pull the covering off. I have done it before but it's a nightmare. So I don't have bleach in my house (I'm athsmatic) and I'm afraid if I use the sanitize setting on my washer/dryer I will never get those coverings back on when they inevitably shrink on me. I usually just throw some vinegar in the load when the kids have accidents or have particularly smelling dirty clothes. Will this be enough to clean the seat coverings or does anyone have any ideas for me?

Now whether hubby likes it or not we're in need of a barn cat or 2!!

Could you tolerate Borax powder? I find that is a good de-smeller without being scented. Hate mouse poo but husband says not cats.

I was worrying more about the nasty stuff mice carry and leave in their droppings. These are the big seats with the backs on them and there is droppings even up along the top head rest so I want to make sure the cleaning kills any nasty stuff the mice may have left behind. I'm careful about the cleaners I use because my athsma is mainly triggered by inhalants so I just don't keep bleach around or I'd pour it on and be sure everything was killed I'm just not sure whether a good wash in the washing machine will be enough to kill and thoroughly clean the coverings so I guess thats what I'm asking.