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Mononucleosis (mono)

Mononucleosis (often called "mono") is an infection that can be caused by several viruses, with the most common one being the Epstein-Barr virus (EBV).  Many children become infected with EBV either without any symptoms or, if symptoms do develop, with a mild illness that is indistinguishable from many other viral illnesses. However, when infection with EBV occurs during adolescence or young adulthood, it causes infectious mononucleosis 35%-50% of the time.

Signs of infections mononucleosis usually occur about 4 to 7 weeks after exposure to the virus.  It usually manifests as a fever, sore throat, and enlarged lymph nodes in the neck.  People also can be tired and not feel hungry.  There may also be an enlargement of the liver and spleen.

Mono is not as easily spread as other viruses such as the common cold.  EBV is found in saliva and mucus.  You may have heard mononucleosis described as the "kissing disease", but there are many other ways that you can obtain the virus, including coughing and sharing utensils.  Transmission of the virus through the air or blood does not normally occur.

The main serious concern with mononucleosis is rupture of the spleen.  The spleen is an organ in the left upper quadrant of the abdomen that helps to filter the blood and produce antibodies; it has the potential to become enlarged during mononucleosis.  Splenic rupture is a rare event in children, and even in adolescents and adults the risk is only 0.2%.  Even though this risk is low, contact sports (even wrestling with siblings at home) should be avoided for 4-6 weeks after recovery.  Our office will let you kinow when you can resume normal activity.

If we believe that your child could have mononucleosis, we will send him/her for bloodwork.  It may take up to 3-4 days for us to obtain the full results of the bloodwork.  When we review the bloodwork, we are looking for an increased percentage of certain "atypical" white blood cells and a positive reaction to a "monospot" test.

There is no treatment for mononucleosis.  Therapy is only to relieve the symptoms.  Most patients require some period of rest.  As with other viruses, you should drink plenty of fluids.  Tylenol or Motrin may also be taken to relieve pain and fever; do not give aspirin!  Occasionally children may become dehydrated because they are unable to drink with the sore throat.  Tonsillar enlargement may cause your child to drool or have difficulty breathing.  If any of these symptoms occur, please call our office immediately.

Mono is a self-limiting disease.  Symptoms usually subside within 2-4 weeks.  The fever and sore throat usually subside after 2 weeks, but the enlarged spleen and lymph nodes may persist for several additional weeks.  In some children, particularly teens, fatigue and weakness can last for weeks, occasionally months.  Remember that every child reacts differently to mononucleosis.  There is also no proven connection between Epstein-Barr virus and chronic fatigue syndrome.


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