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What causes Mononucleosis?

Epstein-Barr virus, or EBV, is one of the most common human viruses in the world. EBV can cause infectious mononucleosis, also called mono, and other illnesses. Most people will get infected with EBV in their lifetime and will not have any symptoms. Mono caused by EBV is most common among teens and adults.

How is Mononucleosis spread?

Person-to-person contact, through saliva. Spread can occur by direct contact, such as kissing, or through items such as toys that are contaminated with saliva.

The virus does not live long on surfaces, so a person must come in contact with fresh saliva to become infected

What are the symptoms of Mononucleosis?

Fever, sore throat, tiredness and swollen glands, especially behind the neck. Sometimes there is a rash. Young adults may have jaundice (yellowing of the skin or eyes) and an enlarged spleen. Infectious mononucleosis usually lasts from one week to several weeks, and it is rarely fatal

How long is it contagious?

From many weeks to a year or more. Some adults can be carriers of the virus

How can I prevent infection?

  1. Frequent, careful hand washing by child care staff, children and household members.
  2. Clean, rinse with clean water, then sanitize mouthed toys at least daily and when soiled
  3. Do not share bottles, straws, lip balm, etc.


For more information, please call the Northern Kentucky Health Department at 859.363.2070 or visit the Centers for Disease Control and Prevention.

Revised November 2014