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What is mononucleosis?

Infectious mononucleosis is a viral disease that affects certain types of white blood cells.  It is usually caused by the Epstein-Barr virus (a member of the Herpes virus family). 

Who gets infections mononucleosis?

Infection can be contracted early in life. In the United States, people are often exposed to the virus when they are older children or young adults. 

How is infection spread?

The virus spreads by person-to-person contact via saliva (e.g., kissing, hands, toys).  In rare instances, the virus has been transmitted by blood transfusion. 

What are the symptoms of infectious mononucleosis?

Fever, sore throat, swollen lymph nodes, headache and general tiredness are common symptoms.  In some cases, the liver and spleen may become affected.  Recovery from mononucleosis usually occurs within several weeks, although, in some cases it can take months for infected persons to fully recover.  The disease is almost never fatal.  

How soon do symptoms appear?

Symptoms can develop 30-50 days after exposed. 

When and for how long is a person able to spread infections mononucleosis?
The virus can be found in the throat while a person is ill and can shed for many months after infection.  After initial infection, the virus can stay dormant for a long period and sometimes can reactivate and shed from the throat again.  This reactivation usually occurs without symptoms. 

What is the treatment for mononucleosis?

No treatment other than rest is needed in most cases. 

What can a person do to prevent spread of mononucleosis?

Most persons exposed to people with mononucleosis have been previously infected and are not at risk.  Transmission requires contact with the saliva of an infected person.  Because the virus can be found in some previously infected healthy people it is best to avoid sharing eating utensils, drinking cups, and similar items. The virus can also spread through coughing and kissing. Frequent handwashing can also help to reduce the risk of infection.

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