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What is it?

Infectious mononucleosis is a contagious illness caused by the Epstein-Barr virus. "Mono" and "kissing disease" are terms popularly used for this very common illness. Almost everyone is exposed to mononucleosis during their life. Cases in young children are generally mild and may be difficult to recognize. 

What are the symptoms?

• fever
• sore throat
• swollen glands in the neck area
• enlarged spleen (occurs in about 50% of people with mono)

How is it spread?

The virus is spread through direct contact of infected saliva. Kissing and contact with hands or toys contaminated with infected saliva are common ways to spread the virus. Sharing food or beverages from the same container or utensil can also transfer the virus from one person to another. The Epstein-Barr virus is shed in the saliva during the illness and for many months after the infection. It takes 4-6 weeks for symptoms to show after the first contact with infected saliva. 

How is it diagnosed?

It is confirmed by blood tests.

What is the treatment?

No treatment other than rest is needed for most people with mononucleosis. Acetaminophen can be taken for fever and aches. The sore throat is worse during the first 5-7 days of illness and subsides over the next 7-10 days. The swollen, tender glands generally subside by the third week. The spleen, an organ found in the upper left abdomen underneath the ribcage, becomes enlarged or swollen in about 50% of people with mono. If you think you have mono:

• consult your family physician
• rest
• do not share food or beverages
• good hand washing helps reduce the spread of infection
• avoid contact sports to prevent trauma to the enlarged spleen
• increase activities as energy level allows
• do not donate blood

Recovery from mono usually occurs in a few weeks, but a very small proportion of individuals can take months to regain their former energy level.

Are there exclusions?

There are no exclusions required for school or work. It will vary among individuals as to how much energy they have to carry out their usual routines. For example, some children may tolerate attending school full time while others may need to be off for several weeks.

For more information please call Public Health at 519-376-9420 or 1-800-263-3456.