What is mononucleosis?

Mononucleosis is an infectious condition caused by the Epstein-Barr virus (EBV), which is part of the herpesvirus family. It is one of the most common viruses and will infect most people at some point in their lives. In the United States, nearly 95% of adults between the ages of 35 and 40 years have been infected with EBV (Source: CDC).

Mononucleosis produces flu-like symptoms, including fatigue, fever, a painful sore throat, aches and pains, and headache. Infectious mononucleosis can also cause swelling of the lymph nodes, the spleen, and the liver. People who have already been infected with the virus typically do not get the disease again, although the virus itself survives forever within cells. The fever and sore throat commonly resolve on their own within 10 days. If your spleen or lymph nodes have become enlarged, the enlargement may persist for up to four weeks. In some cases, fatigue may last for a few months following the illness.

Even though the symptoms of EBV resolve, the virus remains in your body indefinitely and may be present in your saliva. Reactivation of the virus is far less common than other herpes viruses. It can occur at any time, but this does not result in any symptoms. You may be able to spread the infection to others while you are ill or while you are experiencing a symptom-free reactivation of the virus.

Seek prompt medical care if you are being treated for mononucleosis and experience symptoms lasting longer than 10 days, or if you have symptoms that include abdominal pain, difficulty breathing, high fever (higher than 101 degrees Fahrenheit), severe headache, severe sore throat or swollen tonsils, muscle weakness, or yellowing of the skin or the whites of the eyes.


What are the symptoms of mononucleosis?

Symptoms of mononucleosis resemble those of influenza (flu) and include fever, sore throat, aches and pain, cough, and swollen lymph nodes. Typically, symptoms do not last for more than four months.

Common symptoms of mononucleosis

Symptoms and signs of mononucleosis generally resemble those of the flu and include:


What causes mononucleosis?

Infectious mononucleosis is caused by infection with the Epstein-Barr virus (EBV). It is transmitted through saliva from one person to another, hence its nickname, “kissing disease.” When you are exposed to the virus, your immune system will develop antibodies and launch an immune reaction, producing the associated fl... Read more about mononucleosiscauses


How is mononucleosis treated?

Treatment of mononucleosis begins with seeking medical care from your health care provider. To determine if you are infected, your health care provider will ask you to provide blood samples for laboratory testing, which will determine the number of white blood cells in your body. A “mono spot” test may be performed as a rapid test to determine whether you have antibodies to the Epstein-Barr vir... Read more about mononucleosistreatments

Medical Reviewer: William C. Lloyd III, MD, FACS Last Annual Review Date: Sep 6, 2013 Copyright: © Copyright 2014 Health Grades, Inc. All rights reserved. May not be reproduced or reprinted without permission from Health Grades, Inc. Use of this information is governed by the HealthGrades User Agreement.

This Article is Filed Under: Infections and Contagious Diseases

Popular Infections and Contagious Diseases Slide Shows