Mononucleosis is a viral infection with the Epstein-Barr virus, abbreviated as EBV and also called herpes virus 4. Other names for the infection include mono, infectious mononucleosis, glandular fever, and given that it is mainly transmitted through oropharyngeal secretions, the kissing disease.
According to the Center for Disease Control and Prevention (CDC), most people seroconvert at some point in their lives (develop specific antibodies to EBV that become detectable in blood). However, this does not necessarily mean they develop symptoms. Interestingly, in the US around half of the population seroconverts before age 5. The virus infects B lymphocytes, and these proliferate and circulate throughout the body (most importantly: spleen, liver and peripheral lymph nodes) activating several of the body’s defense mechanisms (cytokines, and T-cell response).
While the condition is more common in people aged 15 to 24 years, it can occur at any age. Below are the top 10 symptoms of mononucleosis.
Symptom #1: Fever
Fever is one of the initial symptoms of EBV infectious mononucleosis, but it is rarely the sole manifestation. It may reach 103-104°F but is usually less than 102°F. Persistent fever or reappearance after recovery should suggest an alternate diagnosis. The fever will usually peak in the afternoon or early evening. The fever can last for days to weeks depending on the ability of your immune system to fight against the infection. In the very young and the elderly, mono may manifest by fever and muscle pain only.
Before fever, you may get chills or rapid muscular contraction and relaxation. This is the way your body responds to changes in temperature to produce more heat.