Mono (Infectious Mononucleosis): Causes, Symptoms and Recovery

What it is

Infectious mononucleosis — mono — is a contagious disease caused by viruses, most often the Epstein-Barr virus (EBV). It is common among teenagers and young adults, especially college students.

Causes

EBV is found worldwide, and most people are infected at some point — often in childhood or as young adults — but only some get symptoms of mono. In children, EBV usually causes no symptoms, or symptoms hard to tell from other childhood illnesses such as the flu. Teens and young adults are more likely to get typical mono.

How it spreads: mostly through body fluids, especially saliva — which is why it's called "the kissing disease." Sharing food, drinks, utensils or lip balm with someone who has mono can spread it too. Less commonly, it spreads through blood transfusions, organ transplants, and blood and semen during sex.

Symptoms

Symptoms usually begin four to six weeks after infection (sooner in young children), often slowly and not all at once:

• extreme fatigue;
• fever and sore throat;
• head and body aches;
• swollen lymph glands in the neck and armpits;
• rash;
• less often, a swollen liver, spleen, or both.

Most people recover in two to four weeks, though fatigue can linger for several more weeks, and occasionally symptoms last six months or longer.

Diagnosis

Your provider may diagnose mono from your symptoms and an exam — checking for swollen lymph nodes, tonsils, liver or spleen — and sometimes a mono test.

Treatment

• Drink plenty of fluids, rest, and take over-the-counter medicine for pain and fever — but never give aspirin to children or teens, as it can cause Reye syndrome, a rare, serious illness affecting the brain and liver.
• Antibiotics don't treat viruses, so they don't help mono. If you also have a bacterial infection such as strep throat, you may need antibiotics — but not penicillins like ampicillin or amoxicillin, which can cause a rash in people with mono.
• Severe symptoms may need more treatment, depending on which organs are affected.
• Protect your spleen: mono can enlarge it, and it could rupture — an emergency. Avoid intense exercise and contact sports until you've fully recovered, about a month.

Prevention

There's no vaccine. To lower the chance of catching or spreading mono:

• don't share food, drinks, utensils or lip balm, especially if either of you has mono;
• don't kiss someone if either of you has mono;
• wash your hands often with soap and water.

Sources

Based on "Infectious Mononucleosis," MedlinePlus, National Library of Medicine, drawing on the Centers for Disease Control and Prevention; a work of the United States government in the public domain.