Mononucleosis

Have you ever heard of “the kissing disease”? Mononucleosis (pronounced mon-o-nuke-lee-o-sis, or “mono” for short) got this nickname because people can pass it through their saliva when they kiss. Kissing isn’t the only way you can catch mono, though.

What is mono?

Mono is the name of an infection that is usually caused by the Epstein-Barr virus (EBV). EBV is a very common virus that many people are exposed to when they’re young. The greatest number of people get mono when they are between 15 and 24 years old, particularly between 15 to 17 years old. Some people with EBV might not have symptoms, but may still carry the virus and infect other people, causing them to develop mono.

How does someone get mono?

Kissing a person who has the Epstein-Barr virus (EBV) is just one way of getting mono. There are other ways you can get it, and they all involve coming in contact with bodily fluids (especially saliva) of someone who has the virus.

The virus can be passed through:

• A drink (water bottle, cup, etc.)
• A toothbrush
• A fork or spoon
• Lip balm, lip gloss, or lipstick
• Sexual contact

According to the Centers for Disease Control (CDC), viruses that cause mono can also be spread through blood and semen during sexual contact, blood transfusions, and organ transplantations. Most often, however, mono is spread through saliva.

What are the symptoms of mono?

People who have mono may have different combinations of symptoms, including:

• Swollen glands (neck and armpits)
• Fever
• Sore throat
• Extreme tiredness/weakness
• Decreased appetite
• Headache
• Sore muscles/body aches
• Swollen spleen and/or liver

Is there a test for mono?

A health care provider (HCP) may suggest that you are likely to have mono based on your symptoms and examination, such as sore throat, swollen tonsils with white patches, swollen lymph nodes (in your neck), fever, and fatigue. Your liver and spleen may be enlarged and sore, and some people get a rash, especially if taking antibiotics such as amoxicillin. To make a diagnosis of mono, your HCP will check your blood count and a special “mono spot test.” This test can be negative in the first week of illness and occasionally longer. This test may also stay positive for a year after mono, so if your HCP is not sure about whether you have mono, he/shethey may order a blood test that can show whether you have antibodies against EBV (Epstein-Barr Virus), which can cause mono. There are other causes of mono-like illnesses such as HIV, CMV (cytomegalovirus), other viruses, and some drugs.

How long will I be sick with mono?

If you have a fever, it will usually go away within 10 days. If you have an enlarged liver or spleen, it will usually become normal in 4-6 weeks. Other mono symptoms go away after 2-4 weeks (the length of time varies for each person), but you may continue to feel very tired for about 3-6 months, or even longer. Research has shown that even when a person (who has had mono) feels better, they can still have the virus in their body for a long time.

What is the treatment for mono?

Unfortunately, there isn’t a medicine or pill that can get rid of mono, but there are things you can do to feel better. Do not take antibiotics such as ampicillin or amoxicillin, as they may cause a rash!

Things you can do to help yourself feel better while you have mono:

• Get lots of rest
• Drink plenty of fluids
• Eat healthy foods
• Gargle with salt water (but don’t swallow), drink tea with honey, try throat lozenges, or suck on an ice pop if you have a sore throat
• Ask your health care provider if you can take a small dose of acetaminophen or ibuprofen for pain or fever

When can I get back to school and sports?

You can go back to school when you feel better, which may take a few days to a few weeks. However, you’ll probably still feel tired for a few weeks. Most people get better within a month, but you may need to talk with your teachers or principal if your mono symptoms are severe and are causing you to miss a lot of school. Tell a health care provider (HCP) about all the different types of physical activities you usually participate in. A HCP will decide what activities are safe for you to do and when. In general, most doctors agree that people who have had mono should not participate in sports activities, especially contact sports, during the first 3-4 weeks or until they are completely well, to lessen the chance of their spleen (an organ in the body that filters blood) getting hurt.

Is there any way to prevent getting mono?

You can’t always prevent getting mono, but you can lessen your chance by not sharing your toothbrush, dishes, utensils, and water bottles, and not sharing drinks. If someone you know has mono, be very careful not to share any of these items with them, and don’t kiss them either.

If I have mono, how can I prevent giving it to someone else?

To prevent giving the virus to someone else:

• Cover your mouth if you cough or sneeze
• Don’t share your food, drinks, eating utensils, toothbrush, or any kind of lip product
• Don’t kiss while you are sick (mono can spread through saliva)
• Don’t have sexual contact with someone who has mono

Even though there’s no quick way to get rid of mono, you will probably feel better in a few weeks. The good news is that once you’ve had it, you are unlikely to get it again.

Our health guides are developed through a systematic, rigorous process to ensure accuracy, reliability, and trustworthiness. Written and reviewed by experienced healthcare clinicians from Boston Children's Hospital, a Harvard Medical School teaching hospital and consistently ranked as a top hospital by Newsweek and U.S. News & World Report, these guides combine clinical expertise, specialized knowledge, and evidence-based medicine. We also incorporate research and best practices from authoritative sources such as the CDC, NIH, PubMed, top medical journals, and UpToDate.com. Clinical specialists and subject matter experts review and edit each guide, reinforcing our commitment to high-quality, factual, scientifically accurate health information for young people.