Mononucleosis

Mono is a highly contagious viral infection that usually affects teenagers and young adults. Exposure to the herpes virus, Epstein-Barr, most often causes it. Almost all Americans have been exposed to Epstein-Barr by age 35, but not everyone develops mono.

Most people experience mild cases of mono that go away on their own. If your case is more severe, your symptoms could linger for a month, and you may need medical attention.

Epstein-Barr causes 90 percent of mono cases. Epstein-Barr lingers in your throat and blood cells even after your symptoms disappear. The inactive virus may reactivate during your life, but it’s unlikely to cause symptoms again.

These other viruses can also lead to mono:

• Adenovirus
• Cytomegalovirus
• Hepatitis A, hepatitis B or hepatitis C
• Herpes simplex virus
• Human immunodeficiency virus
• Rubella
• Toxoplasmosis

Kissing is the most common way to spread the mono virus. But you can also pass it in these ways:

• Blood transfusions
• Coughing
• Organ transplants
• Sexual contact
• Sharing food, drinks or utensils
• Sneezing

You can become infected with mono at any time. But two groups are most at risk:

• Early school-age children
• Adolescents and young adults

Most young children don’t experience symptoms. Teens and young adults are much more likely to develop mono. Approximately 25 percent of people this age who have the virus end up getting sick.

Mono affects each person differently. It typically takes four to six weeks for symptoms to appear. Some people experience mild symptoms that clear up on their own. Others have more severe symptoms that linger for four to six weeks.

If you develop mono, you may experience these symptoms for at least four weeks:

• Enlarged liver or spleen
• Fatigue
• Fever
• Headaches
• Loss of appetite
• Muscle aches
• Rash
• Sore throat (may be confused with strep throat)
• Swollen lymph nodes
• Swollen tonsils
• Weakness

If our providers suspect you have mono, they will conduct a physical exam to assess your symptoms. They will also feel your lymph nodes, tonsils, liver and spleen for any swelling. For the most accurate diagnosis, they may also recommend these blood tests:

• Antibody test. This test, called the “monospot” test, detects heterophile antibodies in the presence of the Epstein-Barr virus. Results are usually ready within a day, but they may be inaccurate during the first week of your illness.
• White blood cell count. When you have an infection, your body produces more white blood cells. The results of this blood test can’t confirm you have mono, but it indicates mono may be a possibility.

There is no cure or vaccine for mono. Antiviral medications that treat other viruses don’t clear up the infection. And antibiotics won’t work because bacteria don’t cause mono.

Our providers can recommend these self-care tactics to manage your symptoms until your infection improves:

• Avoid physical activity. Being too active increases pressure on an enlarged spleen, increasing your risk for rupture. Take a break from contact sports or heavy exercise while you’re sick and for at least four weeks after you get better.
• Pain relievers. Over-the-counter medications can reduce your fever, headaches, inflammation and muscle aches.
• Rest. Mono makes you feel exhausted. Get plenty of sleep to help your body fight the infection.
• Sore throat care. Soothe your sore throat with throat lozenges or by gargling with salt water.
• Stay hydrated. Drink enough fluids to avoid dehydration. Water is best.

It’s possible to develop other infections while you have mono. Strep throat is common. You may also get a tonsil or sinus infection. Our providers can treat these infections with antibiotics. If you experience severe swelling in your throat, they may recommend treatment with corticosteroids.

Alongside symptoms that make you feel tired and achy, mono can lead to some potentially serious complications. Other problems include:

• Enlarged spleen. Swelling in your spleen is the most dangerous complication. If your spleen swells too much, it can burst, causing a sudden, sharp pain in the left side of your upper abdomen. Seek emergency care if you feel those signs.
• Liver problems. Mono can cause hepatitis (liver inflammation) or jaundice (yellowing of your skin and whites of your eyes).

Less frequent complications include:

• Airway obstructions
• Anemia (having a low level of red blood cells)
• Heart inflammation (myocarditis)
• Heart rhythm problems
• Kidney inflammation
• Nervous system problems, like encephalitis or meningitis
• Thrombocytopenia (low blood platelet count)

Preventing mono is difficult. No vaccine exists. It also takes weeks for symptoms to appear. So, you can spread the virus to others without even knowing you have it.

Consequently, the best way to prevent mono is by practicing good hygiene. Don’t kiss anyone who still shows signs of active mono. Additionally, don’t share food, dishes or utensils with individuals who are ill.