Overview
Mononucleosis is a viral infection, most often caused by the Epstein-Barr virus, that is common in teenagers and young adults. It spreads mainly through saliva. It typically causes prolonged fatigue, sore throat, and swollen glands, and although it can feel debilitating, most people recover fully with rest over a few weeks.
Symptoms
- Extreme fatigue
- Sore throat
- Swollen lymph nodes in the neck and armpits
- Fever
- Swollen tonsils
- Headache
- Body aches
- Sometimes an enlarged spleen
Causes & risk factors
- Infection with the Epstein-Barr virus (most common)
- Spread through saliva, such as kissing or sharing utensils or drinks
- Occasionally caused by other viruses
Treatment & self-care
There is no specific cure; care centers on rest, fluids, and managing sore throat and fever under medical guidance. Because the spleen can enlarge, clinicians often advise avoiding contact sports and heavy activity for several weeks to prevent rupture. A licensed clinician should confirm the diagnosis and advise on safe return to activity.
See a doctor urgently if
- You have a severe or persistent sore throat or difficulty swallowing
- You have sudden sharp pain in the upper left abdomen (emergency, possible spleen rupture)
- You have trouble breathing or swallowing due to swelling (emergency)
- Fatigue and fever last longer than expected or steadily worsen
- You develop yellowing of the skin or eyes