Infectious Mononucleosis

Mononucleosis (often called "mono") is an infection caused by the Epstein-Barr virus. Infectious mononucleosis is an acute infectious disease caused by the Epstein-Barr virus (EBV), a member of the herpes group. It primarily affects young adults and children, although in children it's usually so mild that it's often overlooked. Characteristically, infectious mononucleosis produces fever, sore throat, and cervical lymphadenopathy (the hallmarks of the disease), as well as hepatic dysfunction, increased lymphocytes and monocytes, and development and persistence of heterophil antibodies. The prognosis is excellent, and major complications are uncommon

Causes

Apparently, the reservoir of EBV is limited to humans. Infectious mononucleosis probably spreads by the oropharyngeal route because about 80% of patients carry EBV in their throats during the acute infection and for an indefinite period afterward.

It can also be transmitted by blood transfusion and has been reported after cardiac surgery as the "post-pump perfusion" syndrome. Infectious mononucleosis is probably contagious from before symptoms develop until the fever subsides and oropharyngeal lesions disappear.

Infectious mononucleosis is fairly common in the United States, Canada, and Europe, and both sexes are affected equally. Incidence varies seasonally among college students (most common in the early spring and early fall) but not among the general population.

Signs and symptoms

Signs and symptoms of mononucleosis may include:

• Fatigue
• Weakness
• Sore throat, perhaps a strep throat that doesn't get better with antibiotics
• Fever
• Swollen lymph nodes in the neck and armpits
• Swollen tonsils
• Headache
• Skin rash
• Loss of appetite
• Soft, swollen spleen

Sometimes, early in the illness, a maculopapular rash that resembles rubella develops; also, jaundice occurs in about 5% of patients. Major complications are rare but may include splenic rupture, aseptic meningitis, encephalitis, hemolytic anemia, and GuillainBarre syndrome. Symptoms usually subside from 6 to 10 days after onset of the disease but may persist for weeks.

Diagnosis

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

• white blood cell count
• heterophile antibody test or monospot test, which, if positive, indicates infectious mononucleosis

Treatment

Most patients recover within 2-4 weeks without medication. Younger children often don't have symptoms, while some older patients may have fatigue for up to 6 weeks.

There is no specific treatment available. Antiviral medications do not help. Steroid medication may be considered for patients with severe symptoms.

To relieve typical symptoms:

• Take acetaminophen or ibuprofen for pain and fever.
• Gargle with warm salt water for sore throat.
• Get plenty of rest. Drink plenty of fluids.
• Avoid contact sports while the spleen is enlarged (to prevent it from rupturing).

Prevention

Mononucleosis is believed to spread through saliva. If you're infected, you can help prevent spreading the virus to others by not kissing them and by not sharing food, dishes, glasses and utensils until several days after your fever has subsided. If you've had mononucleosis, don't donate blood for at least six months after the onset of the illness.

There's no vaccine to prevent mononucleosis.