Infectious Mononucleosis

What is infectious mononucleosis?

Infectious mononucleosis (also called mono) is a viral infection. It is a common infection, but often it causes no symptoms, especially when younger children have it. However, for adolescents and young adults it is a frequent cause of illness and missed school.

How does it occur?

The virus that causes infectious mono is called the Epstein-Barr virus (EBV). It is spread mainly through saliva, which is why it has the nickname "kissing disease." Coughing, sneezing, or sharing drinking or eating utensils can also spread the virus.

Mono is most infectious from right before you start having symptoms until all of the symptoms except for the tiredness start to go away.

What are the symptoms?

After the virus enters the body it can take up to a month before symptoms begin. The first symptoms usually are:

• tiredness
• fever
• headache
• muscle aches.

Many people have extreme tiredness before they have any other symptoms. They may find that they are sleeping 12 to 16 hours a day.

After a few days of fever and aches, other symptoms are:

• sore throat
• swollen tonsils with a yellowish white coating
• swollen glands (lymph nodes) in the neck.

You may also have:

• a loss of appetite
• nausea
• achy joints
• a rash, sometimes including tiny red spots in the mouth.

How is it diagnosed?

Your healthcare provider will ask about your symptoms and examine you. Your provider will look for fever; a red throat with swollen tonsils, sometimes covered with pus; and swollen lymph nodes in the neck. You may also have a red rash, especially on the chest, and an enlarged spleen (in the upper left abdomen).

A blood sample will be taken to test for mono. The first blood test might be negative. If your provider thinks you have mono, you may be asked to return in a few days for another blood test. If you have mono, this second test is usually positive.

You may also have a throat swab to check for strep throat.

How is it treated?

There is no specific drug treatment for mono. Because it is a viral illness, antibiotics are not helpful. The most important thing you can do is to get plenty of rest.

Sometimes the mono infection causes the tonsils to become so big that they nearly block the throat. Your healthcare provider might prescribe steroid medicine to try to decrease the size of the tonsils.

How long will the effects last?

Usually the fever, sore throat, and extreme tiredness last about 1 to 2 weeks. However, the fatigue can last for weeks or months.

An uncommon complication of mono is an abscess (pocket of infection) on 1 or both tonsils. The throat is very painful and swallowing is nearly impossible if you have a tonsil abscess. This infection needs to be treated with antibiotics. Sometimes the abscess needs to be opened by a surgeon.

Another uncommon complication is a ruptured spleen. Like the liver, the spleen can become enlarged during the infection. It can become so swollen that it can actually burst. When this happens you may have sudden severe pain in the abdomen or you may feel like you are going to faint. If you have either of these symptoms, you need to call 911.

It can take several weeks, and in some cases several months, for the body's immune system to overcome the virus, but the illness is less contagious after the fever has been gone a few days.

The Epstein-Barr virus stays in the body even after you recover. You could have mono again, but this does not usually happen.

How can I take care of myself?

• Follow your healthcare provider's instructions.
• Get lots of rest.
• Take acetaminophen or ibuprofen for fever, sore throat, or muscle aches. Do not use more than the recommended dose. Children under 18 years of age should not take aspirin or products containing salicylate (such as Pepto-Bismol) because of the risk of Reye's syndrome unless recommended by a healthcare provider.
• Gargle with warm salt water to reduce swelling and discomfort in your throat.
• Drink more fluids.
• Do not drink alcohol when you have mono. The virus can inflame your liver and alcohol could further hurt your liver.
• Avoid heavy lifting and any kind of jarring activity or contact sport for about 1 month. If your spleen is enlarged from the mono, it could rupture if it is hit or strained. A rupture of the spleen causes severe bleeding and is a medical emergency. Check with your healthcare provider about how long you should avoid these activities. Otherwise, you will be able to slowly return to normal activities.
• Call 911 for emergency medical care if you have sudden, intense abdominal pain.
• Call your provider right away if:
  • You are unable to swallow liquids, even your saliva.
  • You are having trouble breathing.
  • Your skin or fingernails are bluish.
• Call your healthcare provider during office hours if:
  • You have a fever higher than 101.5°F (38.6°C).
  • You start to have chills, nausea, vomiting, or muscle aches.
  • Your symptoms seem to be worsening rather than getting better after a couple of weeks.
  • You have any symptoms that worry you.

How can I help prevent mononucleosis?

The best way to prevent others around you from getting mono is for them to avoid contact with your saliva. They should avoid kissing you and not share food, eating utensils, or drink containers until it has been several days since you stopped having a fever. The virus becomes less contagious at this time.