Definition | Causes | Risk Factors | Symptoms | Diagnosis | Treatment | Prevention

Definition

Mononucleosis is a viral disease characterized by fever, sore throat, swollen lymph glands, and fatigue.

Swollen Glands

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Causes

Mononucleosis is caused by the Epstein-Barr virus (EBV). Found mainly in saliva and mucus, EBV is passed from person to person by intimate behavior, such as kissing.

Risk Factors

Many people get EBV during their lifetime. Factors that increase the likelihood that EBV will develop into mononucleosis include:

  • Contracting EBV after age 10
  • Lowered immune resistance, due to other illness, stress, or fatigue
  • Living in close quarters with a large number of people, such as in a college dormitory

One episode of mononucleosis usually produces permanent immunity.

Symptoms

Signs of mononucleosis usually begin 4-7 weeks after you were exposed to the virus. The initial symptoms may be a sense of general weakness that lasts about one week. This is followed by symptoms that may include:

Diagnosis

Your doctor will ask about your symptoms and medical history. A physical exam will be done. Diagnosis is based on:

Treatment

There is no treatment to cure mononucleosis or to shorten the length of the illness. It usually runs its course in 4-6 weeks, although the fatigue may last longer.

During the first few weeks after diagnosis, patients should avoid contact sports. Inflammation of the spleen from mononucleosis puts individuals at high risk of splenic rupture. This can require surgery, and in rare cases, can be fatal.

Treatment includes:

  • Taking nonprescription pain relievers to lessen aches and pains and control fever— avoid aspirin, especially in children

    • Note: Aspirin is not recommended for children or teens with a current or recent viral infection. This is because of the risk of Reye syndrome. Ask your doctor which other medicines are safe for your child.

  • Gargling with warm, salty water to relieve sore throat

Steroids are sometimes used if the swelling in the throat is interfering with breathing. They can also be used if a complication involving low platelet counts or anemia occurs. This treatment has not been shown to be helpful in mild cases.

  • Rest and fluids
  • No heavy lifting or exercise for at least several weeks after recovery to decrease the risk of rupturing an enlarged spleen

If you are diagnosed with mononucleosis, follow your doctor's instructions.

Prevention

Most people contract the EBV virus sometime during their lives. Prevention is geared toward decreasing the likelihood that EBV will develop into mononucleosis. Follow these guidelines to decrease your risk: