Rodents can carry various parasites, viruses and bacterial infections. Some of the viral disease risk varies by what part of the country you live. It is possible for pets to be exposed to disease by mouth or eating rodents or even just being around them. However, many pets encounter rodents frequently and have no problems. Call your veterinary hospital to see if they need to examine your pet and do any tests. If your pet is showing signs of vomiting, diarrhea or decreased activity, have your pet examined thoroughly by a veterinarian immediately.