Infectious mononucleosis (mono) is often called the kissing disease. The virus that causes mono (Epstein-Barr virus) is spread through saliva. You can get it through kissing, but you can also be exposed by sharing a glass or food utensils with someone who has mono. However, mononucleosis isn't as contagious as some infections, such as the common cold.
You're most likely to get mononucleosis with all the signs and symptoms if you're a teen or young adult. Young children usually have few symptoms, and the infection often goes undiagnosed.
If you have mononucleosis, it's important to be careful of certain complications such as an enlarged spleen. Rest and enough fluids are keys to recovery.
Signs and symptoms of mononucleosis may include:
The virus has an incubation period of about four to six weeks, although in young children this period may be shorter. The incubation period refers to how long before your symptoms appear after being exposed to the virus. Signs and symptoms such as a fever and sore throat usually lessen within a couple of weeks. But fatigue, enlarged lymph nodes and a swollen spleen may last for a few weeks longer.
If you've been experiencing the above symptoms, you may have mononucleosis.
If your symptoms don't get better on their own in a week or two, see your doctor.
The most common cause of mononucleosis is the Epstein-Barr virus, but other viruses also can cause similar symptoms. This virus is spread through saliva, and you may catch it from kissing or from sharing food or drinks.
Although the symptoms of mononucleosis are uncomfortable, the infection resolves on its own without long-term effects. Most adults have been exposed to the Epstein-Barr virus and have built up antibodies. This means they're immune and won't get mononucleosis.
Complications of mononucleosis can sometimes be serious.
Mononucleosis may cause enlargement of the spleen. In extreme cases, your spleen may rupture, causing sharp, sudden pain in the left side of your upper abdomen. If such pain occurs, seek medical attention immediately — you may need surgery.
Problems with your liver also may occur:
Mononucleosis can also result in less common complications, including:
The Epstein-Barr virus can cause much more serious illness in people who have impaired immune systems. People with weakened immune systems may include people with HIV/AIDS or people taking drugs to suppress immunity after an organ transplant.
Mononucleosis is spread through saliva. If you're infected, you can help prevent spreading the virus to others by not kissing them and by not sharing food, dishes, glasses and utensils until several days after your fever has improved — and even longer, if possible. And remember to wash your hands regularly to prevent spread of the virus.
The Epstein-Barr virus may persist in your saliva for months after the infection. No vaccine exists to prevent mononucleosis.
Your doctor may suspect mononucleosis based on your signs and symptoms, how long they've lasted, and a physical exam. He or she will look for signs such as swollen lymph nodes, tonsils, liver or spleen, and consider how these signs relate to the symptoms you describe.
There's no specific therapy available to treat infectious mononucleosis. Antibiotics don't work against viral infections such as mono. Treatment mainly involves taking care of yourself, such as getting enough rest, eating a healthy diet and drinking plenty of fluids. You may take over-the-counter pain relievers to treat a fever or sore throat.
Treating secondary infections and other complications. A streptococcal (strep) infection sometimes goes along with the sore throat of mononucleosis. You may also develop a sinus infection or an infection of your tonsils (tonsillitis). If so, you may need treatment with antibiotics for these accompanying bacterial infections.
Severe narrowing of your airway may be treated with corticosteroids.
Besides getting plenty of rest, these steps can help relieve symptoms of mononucleosis:
Take an over-the-counter pain reliever. Use pain relievers such as acetaminophen (Tylenol, others) or ibuprofen (Advil, Motrin IB, others) as needed. These medicines have no antiviral properties. Take them only to relieve pain or a fever.
Use caution when giving aspirin to children or teenagers. Though aspirin is approved for use in children older than age 3, children and teenagers recovering from chickenpox or flu-like symptoms should never take aspirin. This is because aspirin has been linked to Reye's syndrome, a rare but potentially life-threatening condition, in such children.
Most signs and symptoms of mononucleosis ease within a few weeks, but it may be two to three months before you feel completely normal. The more rest you get, the sooner you should recover. Returning to your usual schedule too soon can increase the risk of a relapse.
To help you avoid the risk of rupturing your spleen, your doctor may suggest that you wait about one month before returning to vigorous activities, heavy lifting, roughhousing or contact sports. Rupture of the spleen results in severe bleeding and is a medical emergency.
Ask your doctor about when it's safe for you to resume your normal level of activity. Your doctor may recommend a gradual exercise program to help you rebuild your strength as you recover.
Mononucleosis can last weeks, keeping you at home as you recover. Be patient with your body as it fights the infection.
For young people, having mononucleosis will mean some missed activities — classes, team practices and parties. Without a doubt, you'll need to take it easy for a while. Students need to let their schools know they are recovering from mononucleosis and may need special considerations to keep up with their work.
If you have mononucleosis, you don't necessarily need to be quarantined. Many people are already immune to the Epstein-Barr virus because of exposure as children. But plan on staying home from school and other activities until you're feeling better.
Seek the help of friends and family as you recover from mononucleosis. College students should also contact the campus student health center staff for assistance or treatment, if necessary.
If you suspect you have mononucleosis, see your family doctor. Here's some information to help you get ready for your appointment and know what to expect from your doctor.
Preparing a list of questions will help you make the most of your time with your doctor. For mononucleosis, some basic questions to ask your doctor include:
Don't hesitate to ask any other questions.
Your doctor is likely to ask you a number of questions, including:
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