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Infectious Mononucleosis (mono, EBV mononucleosis)

What is infectious mononucleosis?

Infectious mononucleosis is a viral disease that affects certain types of white blood cells. It is caused by the Epstein-Barr virus (EBV), which is a member of the herpes virus family. Most cases occur sporadically and outbreaks are rare. Infectious mononucleosis is not reportable in New York City.

Who gets infectious mononucleosis?

While most people are exposed to the Epstein-Barr virus at some point in their lives, very few go on to develop the symptoms of infectious mononucleosis. In underdeveloped countries, people are exposed in early childhood when they are less likely to develop symptoms. In developed countries, such as the United States, persons are usually not exposed until older childhood or young adulthood when symptoms are more likely to result. For this reason, infectious mononucleosis is seen more often in high school and college students in the United States.

How is infectious mononucleosis spread?

The virus is spread by person-to-person contact, via saliva (on hands or toys, or by kissing). In rare instances, the virus has been transmitted by blood transfusion.

What are the symptoms of infectious mononucleosis?

Symptoms include fever, sore throat, swollen glands, and fatigue. Sometimes, the liver and spleen are affected. Recovery usually occurs within several weeks, although some infected persons can take months to fully recover. The disease is almost never fatal.

How soon after infection do symptoms appear?

Symptoms appear from 4 to 6 weeks after exposure.

When and for how long is a person able to spread infectious mononucleosis?

The virus is shed in the throat during the illness, and for up to a year after infection. After the initial infection, the virus tends to become dormant for a prolonged period but can later reactivate and be shed from the throat again.

What is the treatment for infectious mononucleosis?

No treatment other than rest is needed in most cases.

How can infectious mononucleosis be prevented?

Avoid activities (e.g., kissing, sharing eating utensils) involving contact with body fluids, such as saliva, from someone who is currently or recently infected with the disease. At present, there is no vaccine available to prevent infectious mononucleosis.