Mononucleosis (Mono)

Infectious mononucleosis (mono) is a viral disease that affects certain blood cells. It is caused by the Epstein-Barr virus, which is a member of the herpesvirus family.

Most people are exposed to the virus at some point in their lives, but very few have mono symptoms. High school and college students are at a higher risk for mono.

The virus is spread by person-to-person contact through saliva. In rare instances, the virus has been transmitted by blood transfusion. After the initial infection, the virus can become dormant for a lengthy period but can later reactivate.


You can protect yourself from mono by avoiding the body fluids of someone who has the disease.


Symptoms of mono will appear at four-to-six weeks after exposure. Symptoms include fever, sore throat, swollen glands and tiredness. In some cases, the liver and spleen are affected. Symptoms can last from one to several weeks.

Mono is rarely fatal.


The only treatment needed in most cases is rest. There is no vaccine available to prevent mono.

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