You might be able to get some of the antibiotic Baytril from a pet store, and you would put it in her water. Mice can be treated pretty much just like people, what would work and help you would also work on them, but on a mouse sized scale. If it's just a cold, pretty much nothing but time will cure it, antibiotics are for infections, like bacterial, they don't work on viruses; treating symptoms is useless, but can be done. | 
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