What is mononucleosis?

Diana Meeks
Diana Meeks on behalf of Sigma Nursing
Family Practitioner

Mononucleosis is a viral infection caused by the Epstein-Barr virus (EBV). The virus causes fatigue, fever, sore throat, and swollen lymph nodes. Mild cases are called EBV infections; cases with severe symptoms are called mononucleosis. The word mononucleosis refers to the elevated number of mononuclear white blood cells present in the blood. EBV is transmitted by saliva, and this illness is often called the kissing disease.

Infectious mononucleosis (mono) is an illness that causes fever, sore throat and swollen lymph nodes. It is primarily caused by the Epstein-Barr virus (EBV), which is a member of the herpes virus family. It is spread through intimate contact with body fluids, generally from saliva. 

Mononucleosis (also known as "mono") is a virus that is most often found in children and adolescents. It is passed through saliva exchange and is sometimes known as the "kissing disease." Besides a severe sore throat, symptoms of mononucleosis can include fatigue, weakness, aches, dizziness, swollen lymph nodes in the neck and an enlarged spleen.

Mononucleosis can only be diagnosed by using a blood test. Since mononucleosis is a virus, there are no antibiotics that treat it. General treatment for mono is rest, plenty of fluids and acetaminophen for the aches and pains. Mono may last for several weeks, and the symptoms may recur for several months. The lymph nodes may remain enlarged for several months even after the rest of the symptoms have gone away. If you think that you or your child has mono, call your doctor.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.