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Infectious Mononucleosis in Adolescents

What is infectious mononucleosis?

Infectious mononucleosis, also known as mononucleosis, "mono," glandular fever, or sometimes the "kissing disease," is characterized by swollen lymph glands and prolonged fatigue.

What causes infectious mononucleosis?

Infectious mononucleosis is either caused by the Epstein-Barr virus (EBV) or the cytomegalovirus (CMV), both of which are members of the herpes simplex virus family. Consider the following statistics:

  • When children are infected with the virus, they usually do not experience any noticeable symptoms. However, many uninfected adolescents and young adults who come in contact with the virus may develop infectious mononucleosis.

  • The cytomegalovirus is actually a group of viruses in the herpes simplex virus family. Most healthy persons who become infected with the CMV virus have few, if any, symptoms and have no long-term effects on their health. Some people may develop symptoms of mononucleosis. 

  • The Epstein-Barr virus (EBV) may cause infectious mononucleosis in adolescents and young adults. However, even after the symptoms of infectious mononucleosis have disappeared, the EBV will remain dormant in the throat and blood cells during that person's lifetime. The virus can reactivate periodically, however, usually without symptoms. The same is true for CMV.

What are the symptoms of infectious mononucleosis?

Mononucleosis usually lasts two to four months. Malaise and difficulty concentrating may last for months longer. EBV is not, however, a cause of chronic fatigue syndrome. The following are the most common symptoms of mononucleosis. However, each adolescent may experience symptoms differently. Symptoms may include:

  • Fever

  • Headache

  • Swollen lymph glands in the neck, armpits, and groin

  • Prolonged fatigue and muscle aches

  • Sore throat due to tonsillitis, which often makes swallowing difficult

  • Enlarged spleen

  • Liver involvement, such as mild liver damage that can cause temporary jaundice, a yellow discoloration of the skin and eye whites due to abnormally high levels of bilirubin (bile pigmentation) in the bloodstream

Once a person has had mononucleosis, the virus remains dormant for the rest of that person's life. Once a person has been exposed to the Epstein-Barr virus, a person is usually not at risk for developing mononucleosis again, unless it is from CMV.

How is infectious mononucleosis diagnosed?

In addition to a complete medical history and physical examination of your adolescent, a diagnosis of mononucleosis is usually based on reported symptoms. However, diagnosis can be confirmed with specific blood tests including:

  • White blood cell count

  • Antibody test

How is infectious mononucleosis spread?

Mononucleosis is often spread by contact with oral secretions through infected saliva from the mouth. According to the CDC, symptoms can take between four to six weeks to appear and usually do not last beyond four months. Transmission is impossible to prevent because even symptom-free people can carry the virus in their saliva.

What is the treatment for infectious mononucleosis?

Alleviating symptoms of mononucleosis may include the following:

  • Rest for about one month (to give the body's immune system time to destroy the virus)

  • Corticosteroids (to reduce swelling of the throat and tonsils)

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