Mononucleosis, or mono, is a contagious viral infection. It's caused by the Epstein-Barr virus (EBV). Most babies and children exposed to the virus get only mild flu-like symptoms or no symptoms at all. But infection is usually more serious in teens and young adults. While the virus is most active, it causes symptoms and can easily spread to others. After symptoms ease, the virus stays in the body for life., It becomes mostly inactive. But it can become active again at times, often with no symptoms. At this point it can spread to others. This is especially true in people with a weak immune system.

The virus isusually spread through saliva, often by kissing, or by sharing food or eating utensils.  It may also spread by breastmilk, blood, or sexual contact.  It takes about 4 to 6 weeks for symptoms to show up after exposure.

Early symptoms include headache, nausea, tiredness, and general muscle aching. This is followed by sore throat and fever. Lymph glands in the neck, under the arms, or in the groin may be swollen. Symptoms usually go away in about 1 to 2 months. But they can last 4 months or longer.

In the first few days to weeks, the monospot blood test may be used to diagnose this disease. But that test may be negative even though you have the infection. Other blood tests are more accurate and may be done instead.

Taking the antibiotic medicine ampicillin or amoxicillin during a mono infection may cause a skin rash. This is not serious and will fade in about a week. The rash usually is not because you had an allergic reaction to the medicine.

Mono can cause your spleen to swell. The spleen is a fist-sized organ in the upper left abdomen. It stores red blood cells and helps fight infections. Injury to a swollen spleen can cause the spleen to break open (rupture). This can cause life-threatening internal bleeding. To prevent this from happening, don't play contact sports or do strenuous activity for 8 weeks, or until your healthcare provider says it's OK. A sharp blow or pressure to the area could rupture a swollen spleen

Home care

  • Rest in bed until the fever and weakness have gone away.

  • Drink plenty of fluids, but don't drink alcohol. Otherwise, you may eat a regular diet.

  • Ask your healthcare provider about using over-the-counter medicines to treat symptoms such as fever, pain, or an itchy rash.

  • Over-the-counter throat lozenges may help soothe a sore throat. Gargling with warm salt water (1/2 teaspoon in 1 glass of warm water) may also be soothing to the throat.

  • You may return to work or school after the fever goes away and you are feeling better. Continue to follow any activity limits you have been given. This might be not playing contact sports or doing heavy lifting.

Preventing spread of the virus

It's very difficult for people with EBV infection not to spread it to others. People are infectious for a few weeks before symptoms show up. They are highly infectious when they have symptoms. They are somewhat infectious from time to time for the rest of their life. To limit the spread of the virus, don't expose others to your saliva while you are feeling symptoms of mono . Don't kiss anyone or share utensils, drinking glasses, or toothbrushes. After this, no precautions are advised or are practical.

Follow-up care

Follow up with your healthcare provider within 1 to 2 weeks, or as advised. This is to be sure you don't have any complications. If symptoms of extreme fatigue and swollen glands last longer than 2 to 3 months, see your healthcare provider. You may need more test or other possible treatments such as corticosteroids.

When to seek medical advice

Call your healthcare provider right away if any of the following occur:

  • Excessive coughing

  • Yellow skin or eyes

  • Trouble swallowing

  • Dizziness

  • Paleness

  • Symptoms get worse or you have new symptoms

Call 911

Call 911 if any of the following occur:

  • Severe or worsening abdominal pain

  • Trouble breathing

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