Personally I wouldn't chance the mousie germs. Unless they are battery operated or have air-filled squeekers, you could still chuck them in the washing machine (I've done this with loads of toys, since lots of ours came from the op shop) or if they are older and more delicate you could wash them by hand, maybe using something like napisan which has a sterilising element. If they are solid-plastic ones you could run them through the dishwasher or even a quick dunk in hot soapy water, again depending if they have squeekies inside.