I always knew that I didn’t like mice sneaking into the house although they seem to do it every year when snow comes, looking for warmth and food. However, I didn’t know that they could make your family sick and cause pregnant women to miscarry. Rats and mice can cause more than 35 diseases, worldwide.

One virus that rodents may carry called LCMV (Lymphocytic Choriomeningitis Virus) can cause severe birth defects such as hydrocephalus, psychomotor retardation, blindness, or miscarriage. Therefore, women who are pregnant or plan to become pregnant in the near future should not have contact with rodents or have them for pets.

Some of the diseases in the United States, which rodents can transmit are Hantavirus pulmonary syndrome, Rat-bite fever, Leptospirosis, Lymphocytic choriomeningitis, and the Plague.

LCMV can cause infection in animals and humans. Infection can occur through being bitten or having contact with an infected rodent’s urine, blood, saliva, droppings, or nesting materials. Inhaling the dust while sweeping, vacuuming, or cleaning up the droppings of an infected animal can also cause infection. Infection is not known to occur from exposure to another person who has LCMV other than from an infected mother to her unborn child or from an infected organ donor to the recipient.

Pets such as hamsters, pet mice, and guinea pigs become infected by exposure to wild mice. Infection can occur in a rodent breeding facility, in a laboratory using rodents, in a pet store, or in your home if wild mice are present.

There is no treatment for LCMV infection, currently available. However, a blood test is available that can detect current or previous LCMV infection. Fortunately, having a previous LCMV infection from which you are over, is not a risk for current or future pregnancies.

If adults had a blood test to check for previous LCMV infection about 5% of them would find out that they were infected at some time during their lives. Those with a normal immune system may not know they are infected because they may not display any symptoms. Other people may feel mildly ill, with symptoms such as headache, fever, chills, and muscle aches. Occasionally, LCMV infection may result in Aseptic meningitis but the infection is rarely fatal.

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(Detailed information on LCMV for pet owners, physicians, and the public.)

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