What is it?
Infectious mononucleosis ("mono" for short) is a viral infection that affects lymph nodes ("glands").

How do you catch it?
How one catches mono is not really known; however, many medical authorities believe that secretions from the nose and throat spread the virus. Thus close contact (e.g. sneezing or kissing) may spread it. Some people may have mono without knowing it, so you can get it without remembering contact with anyone who had it.

What are the symptoms?

  • Sore throat
  • Swollen lymph nodes ("glands")
  • Tiredness
  • Fever
  • Headaches


  • Rash
  • Jaundice (appearing yellow-skinned)

Symptoms go away before the virus leaves the body, so you may be contagious while improving. Associated bacterial infections can also occur, including strep throat.

How is the diagnosis made?
Findings on blood counts and a mono blood test will tell you if you have mono. Sometimes the mono test is negative even if you have mono. There are other mono-like illnesses with negative mono tests; treatment in all these cases is the same.

Will you be hospitalized?
It is not common to hospitalize patients with mono unless the symptoms are especially severe. You may, however, need help in your apartment or dorm for a few days until you begin to feel better.

What can you do?
Viruses do not respond to antibiotics. However, there are a number of things that you can do to feel better.

  • GARGLE with warm salt water (1/4 teaspoon of table salt and 1/2 cup tap water) as often as desired to soothe sore throat.
  • USE LOZENGES according to package instructions or hard candy to relieve throat discomfort.
  • TAKE ASPIRIN (10 grains) or ACETAMINOPHEN (650 mg) every 4-6 hours for fever anddiscomfort unless a physician advises against these medications.
  • APPLY WARM, MOIST TOWELS to neck, where swollen, as often as desired.
  • REST. This is no time to be jogging, playing sports, or exercising. Do not tire yourself unnecessarily. Resting does not mean you should stop all your normal daily routines - but besensible.
  • AVOID PRESSURE TO THE ABDOMEN. This means no heavy lifting, no contact sports, no vigorous sexual activity. Anytime you develop a tender abdomen seek medical attention. We make these recommendations because the spleen and/or liver are usually enlarged, and, though rare, rupture of the spleen can occur.
  • DO NOT DRINK ALCOHOL, especially if your liver is large or you have jaundice.
  • PRACTICE GOOD HYGIENE: Wash your hands, cover your nose and mouth when sneezing, and properly dispose of all used facial tissues. As with all contagious illnesses, consider others when making decisions about sexual activity.

Consult health care personnel:

  • if you suspect you have mono.
  • if symptoms of mono persist more than 2 weeks.
  • if sore throat or swollen glands are worse.
  • if you develop abdominal pain or jaundice (yellow skin).
  • if you have a fever of 101 degrees F (38.3 degrees C) for more than 2 days.
  • if any symptoms worry you.
  • anytime you are unsure of what to do.
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