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Mononucleosis

(Infectious Mononucleosis; Mono)

Definition

Mononucleosis is an infectious disease that is associated with fever, fatigue, and swollen lymph glands.
Swollen Glands
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Causes

Mononucleosis is caused by the Epstein-Barr virus (EBV). Found mainly in saliva and mucus, EBV is passed from person to person by intimate behavior, such as kissing.

Risk Factors

Many people get EBV during their lifetime. Factors that increase the likelihood that EBV will develop into mononucleosis include:
One episode of mononucleosis usually produces permanent immunity.

Symptoms

Signs of mononucleosis usually begin 4-7 weeks after you were exposed to the virus. The initial symptoms may be a sense of general weakness that lasts about 1 week. This is followed by symptoms that may include:

Diagnosis

You will be asked about your symptoms and medical history. A physical exam will be done.
Your bodily fluids may be tested. This can be done with blood tests.

Treatment

There is no treatment to cure mononucleosis or to shorten the length of the illness. It usually runs its course in 4-6 weeks, although the fatigue may last longer.
During the first few weeks after diagnosis, you should avoid contact sports and lifting anything heavy. Inflammation of the spleen from mononucleosis puts you at high risk of splenic rupture. This can require surgery. In rare cases, it can be fatal.
It is important to get plenty of rest. Other supportive care may involve:

Prevention

Most people contract the EBV virus sometime during their lives. Prevention is geared toward decreasing the likelihood that EBV will develop into mononucleosis. This can be done by:

RESOURCES

Centers for Disease Control and Prevention http://www.cdc.gov

National Institute of Allergy and Infectious Diseases http://www.niaid.nih.gov

CANADIAN RESOURCES

About Kids Health—The Hospital for Sick Children http://www.aboutkidshealth.ca

The College of Family Physicians of Canada http://www.cfpc.ca

References

Balfour HH Jr, Hokanson KM, et al. A virologic pilot study of valacyclovir in infectious mononucleosis. J Clin Virol. 2007;39:16-21.

Epstein-Barr virus-associated mononucleosis. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated May 11, 2015. Accessed June 9, 2015.

Luzuriaga K, Sullivan JL. Infectious mononucleosis. N Engl J Med. 2010 May 27;362(21):1993-2000.

Mononucleosis. Academy of Family Physicians Family Doctor website. Available at: http://familydoctor.org/familydoctor/en/diseases-conditions/mononucleosis.html. Updated March 2014. Accessed June 9, 2015.

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