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Mononucleosis, Infectious

(mono, Epstein-Barr virus, EBV mononucleosis)

Infectious mononucleosis is an acute viral disease most commonly caused by the Epstein-Barr virus (EBV). It is not a reportable disease in Wisconsin and the number of cases is unknown.

While most people are exposed to the Epstein-Barr virus sometime in their lives, as few as 50% will develop the symptoms of infectious mononucleosis. In developed countries such as the United States, the age of first exposure may be delayed until older childhood and young adulthood when symptoms are more likely to result. For this reason, it is recognized more often in high school and college students.

The virus is spread by person-to-person contact, via saliva (on hands, toys, or by kissing).

Mononucleosis fact sheet, P-42063

About Mononucleosis – Centers for Disease Control and Prevention

Last revised September 21, 2021