LCMV Facts

A rodent breeding facility in Indiana was diagnosed with LCMV in May 2012. Mice from the infected facility have been distributed to pet stores in Indiana as feeders for reptiles, but may have been purchased by individuals for pets or replacement breeding stock. Rodents that came into contact with the infected mice may have picked up the virus.

A small percentage of wild house mice have LCMV. The virus has also been found in some breeding populations of mice which can lead to pet or feeder mice having the virus. Some mice can carry this virus their entire lives without showing any signs of illness. Other rodents, like hamsters, gerbils, and guinea pigs, that have contact with mice can also get the virus.

People can get LCMV by handling and being around rodents. Urine, droppings, saliva and nesting materials (animal bedding) of rodents that contain LCMV can spread the virus. The virus can be in the air or around these materials. Breathing this air, or coming into direct contact with these materials then touching the nose, eyes, or mouth, or open skin wounds can cause an infection. The virus is not spread person-to-person. Women who get LCMV when they are pregnant can pass the virus to their unborn babies.

Most healthy people who get LCMV will not have any symptoms or will only have a mild illness that may include fever, loss of appetite, headache, muscle aches, chills, nausea, and vomiting. Other symptoms that can occur are sore throat, cough, and pain to the joints, chest, testicles, or mouth. Some people may develop a more severe form of disease 1 to 2 weeks after the fever starts. This severe form can cause swelling in the brain that may require hospitalization. A woman who gets LCMV while pregnant may have a miscarriage or a baby with severe birth defects.

See your doctor immediately if you think you are sick with LCMV. Tell your doctor if you have been around any wild mice, feeder mice, or pet rodents. Especially if you are pregnant or have a weak immune system. Your doctor can decide if you need to be tested and how best to treat your symptoms.

Rodents and other pets from any pet store have some risk of diseases and should be handled with caution. Rodents infected with LCMV may look and act normally. For more information on how to reduce the risk of diseases from a pet, please see the CDC Healthy Pets Web site: www.cdc.gov/healthypets.

People who have mice, hamsters or other rodents from pet stores should not return their animals to the stores. People who no longer wish to keep their pet rodent should consult a veterinarian.

No. Pet rodents should never be released into the wild. This is not humane and is illegal in many states. Pet rodents often starve or are killed by predators. Many pet rodents are not native species to North America. If the animal does survive in the wild, it could become a pest, endanger native wildlife, or damage the normal ecosystem.

Testing on live rodents can be inaccurate and misleading. Reliable testing requires the animal to be killed. Always assume that pet animals are capable of spreading disease. Follow precautions as described on CDC's Healthy Pets Website (www.cdc.gov/healthypets) when handling any pets.