The mono test is a rapid blood test for diagnosing infectious mononucleosis (mono). This test is often prescribed for adolescents exhibiting symptoms typical of mononucleosis, such as fever, fatigue, sore throat, swollen glands, etc. These symptoms appear approximately three to four weeks after infection and can last for several weeks. Fatigue associated with mononucleosis can last several months. Mononucleosis is an illness that is usually cured on its own, without any specific treatment.
Mononucleosis is caused by the Epstein-Barr virus (EBV). The test screens for antibodies (heterophile antibodies) produced by the body in response to the virus. About 75% of affected individuals will produce the antibodies detected by the test. In the 25% of individuals who do not produce heterophile antibodies, further testing is required to confirm the diagnosis (Anti-EBV IgG and IgM antibodies). A positive mono test is often confirmed by a complete blood count showing a high white cell count and the presence of atypical lymphocytes.