“Mono” (infectious mononucleosis) is a contagious infection that can cause fever, sore throat, fatigue, and enlarged lymph nodes in the neck. Commonly called “the kissing disease,” mono often affects adolescents and young adults. It is uncommon in adults over 40 years.
Symptoms of mono in adults may come on slowly and usually develop four to eight weeks after infection.
Symptoms of infectious mononucleosis in older adults are often mistaken for lymphoma, leukemia, or biliary obstruction, or may be classified as “fever of unknown origin.”
Symptoms of mono that are more common in older adults include:
- Fever (temperature greater than 100.4°F or 38°C)
- Swollen liver
- Body aches
Other symptoms of mono may include:
- Extreme fatigue, which may last for more than a month
- Sore throat
- Headache
- Swollen lymph nodes in the neck and armpits
- Rash
- Enlarged spleen
Older adults with mono often do not have the same symptoms as children and younger adults such as swollen lymph nodes, sore throat, enlarged spleen, or increased white blood cells.
What Causes Mono in Adults?
The Epstein-Barr virus (EBV) is the most common cause of mono (infectious mononucleosis) in children and adults.
EBV is typically bodily fluids, especially saliva, through kissing (mono is often called “the kissing disease”), sharing eating utensils, or drinking from the same glass as someone infected with the virus. It can also be spread through blood and semen during sexual contact, blood transfusions, and organ transplantations.
EBV exposure usually happens during childhood, although people may not realize it at the time because they may not have any symptoms or symptoms are mild.
While EBV is the most common cause of mono, other infections that can cause mono include:
- Cytomegalovirus (CMV)
- Toxoplasmosis
- Human immunodeficiency virus (HIV)
- Rubella
- Hepatitis A, B, or C
- Adenovirus
How Is Mono in Adults Diagnosed?
Mono (infectious mononucleosis) in adults is diagnosed with a patient history and physical examination. A diagnosis of mono is usually based on symptoms and lab tests are not needed.
- Monospot blood test: Sometimes a blood test called the Monospot is used to confirm a diagnosis. However, the Monospot test often comes back with false negatives early in the illness so it’s not always reliable.
- Other blood tests: Sometimes, additional blood tests may be used to identify the cause of illness in people who do not have typical cases of infectious mononucleosis.
What Is the Treatment for Mono in Adults?
Mono (infectious mononucleosis) in adults is generally not considered a serious illness and most people recover completely within one to four weeks without any complications. Some people may continue to feel fatigue for several more weeks. Rarely, symptoms of mono last six months or more.
Mono is caused by a virus, so antibiotics are not used to treat it. There are currently no antiviral medications that are effective to treat or cure Epstein-Barr virus.
The goal of treatment for mono is the relief of symptoms. Home remedies to relieve symptoms of mono in adults may include:
- Getting plenty of rest
- Drinking adequate fluids
- Over-the-counter (OTC) medications for pain and fever
- Avoid contact sports until you fully recover
- Mono may cause the spleen to become enlarged and strenuous activities such as sports may cause the spleen to rupture
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https://www.cdc.gov/epstein-barr/about-mono.html
https://www.uptodate.com/contents/infectious-mononucleosis-mono-in-adults-and-adolescents-beyond-the-basics?search=Infectious%20mononucleosis&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1
https://pubmed.ncbi.nlm.nih.gov/2244552/