About Lymphocytic Choriomeningitis

What it is

LCM is caused by the lymphocytic choriomeningitis virus. LCM has been reported in Europe, the Americas, Australia, and Japan, and may occur wherever infected rodents are found. LCM is underreported, making it difficult to determine how common it is and where else it is found.

Signs and symptoms

People who do get symptoms are usually sick for about a week and may experience:

• Fever
• Fatigue
• Lack of appetite
• Muscle aches
• Headaches
• Nausea
• Vomiting

Less common symptoms include sore throat, cough, and pain in the chest, testicles, or glands in the mouth.

After a few days of recovery, a second, more serious phase of illness may occur. This phase involves neurologic distress like a buildup of fluid on the brain and inflammation of the brain, its membranes, and the spinal cord.

Neurologic symptoms can include:

• Fever
• Headache
• Stiff neck
• Drowsiness
• Confusion
• Inability to move
• Muscle weakness

How long it takes for signs to show

People with LCM start showing signs of the disease about 8-13 days after being infected with the virus.

Possible complications

Most people with LCM survive. Less than 1 percent of people pass away from the disease.

Even most patients who experience more severe brain symptoms survive. However, temporary or permanent nerve damage is possible. After recovering, some people develop deafness, arthritis, or swelling of the heart.

People who get LCM during pregnancy may pass the infection on to their fetus. Infections in the first trimester may result in miscarriage. Infections in the second and third trimesters can cause serious birth defects.

Risk factors

Other people at risk:

• Owners of pet mice and hamsters if their pets came from infected colonies or are infected by wild mice.
• Laboratory workers who work with the virus or handle infected animals.

Risk factors for severe disease:

• Immunocompromised people, including organ transplant recipients, are at a higher risk of experiencing fatal hemorrhagic fever-like disease.
  • 70 percent of immunocompromised people infected with LCM will die.
• Pregnant people with LCM are at a higher risk for miscarriage.
  • It is also possible to pass the infection onto the fetus.
• Infected newborns can have build-up of fluid deep in the brain, abnormal deposits of calcium in the brain, or swelling in the eye.
  • 70 percent of newborns with these birth defects die. Around 35 percent of all newborns with LCM die.

How it spreads

Someone can get LCM when they are exposed to fresh urine, droppings, saliva, or nesting materials from infected rodents.

Except for transmission to the fetus during pregnancy, spread between people has not been reported. Rarely, someone may contract LCM if they receive an organ transplant from an infected person.

Prevention

You can protect yourself from LCM by avoiding contact with wild mice. Take precautions when handling pet rodents like mice, hamsters, or guinea pigs.

Testing and diagnosis

Healthcare providers diagnose LCM by testing for the virus or its antibodies in a patient's blood or spinal fluid.

Treatment and recovery

LCM has no treatment. Although some studies have shown the drug ribavirin may be effective against LCM, there is not enough evidence to support its use in all cases.

People who develop neurological symptoms require hospitalization. They may receive anti-inflammatory drugs, like corticosteroids.