13974 Mononucleosis

Overview

Mononucleosis, often called 'mono,' is a common viral infection. It is also known as glandular fever in the UK. It is usually harmless and most people get better on their own with rest. The virus is typically the Epstein-Barr virus (EBV), which spreads through saliva.

Yes, it is very common. Most people have been exposed to the virus by the time they are adults, often with no symptoms.

It most often affects teenagers and young adults in their teens and 20s. Children can catch it too, but they usually have milder symptoms.

Symptoms

Common symptoms

• Extreme tiredness (fatigue)
• Sore throat
• Fever
• Swollen glands in the neck, armpits, or groin
• Headache
• Muscle aches
• A general feeling of being unwell

Symptoms in children

• Most children have no symptoms or only mild ones, like a slight fever, fussiness, or a runny nose.

Symptoms in older adults

• Older adults may not have a clear sore throat or swollen glands. They might have a fever, tiredness, and aches that are easy to mistake for a bad cold or flu.

Causes

Main causes

• The Epstein-Barr virus (EBV) is the most common cause of mono.
• EBV is passed through saliva, which is why it is sometimes called 'the kissing disease.'
• You can also catch it by sharing a drink, eating utensil, toothbrush, or other items that have saliva on them.

Risk factors

• Being a teenager or young adult in close contact with many people (for example, at college or in the military)
• Sharing personal items like cups, bottles, or toothbrushes
• Having a weakened immune system due to another illness or treatment

When to see a doctor

See a doctor urgently if:

• If you have severe belly pain, trouble breathing, or extreme weakness, get medical help right away.
• If you are unable to keep fluids down for more than a day, you may need medical care.

Book a routine appointment if:

• If you have a sore throat, fever, or swollen glands that last more than a few days
• If you are so tired that you cannot do your normal daily activities
• If your symptoms get worse after getting better

Diagnosis

Your doctor will ask about your symptoms and do a physical exam. They will check your throat, feel your neck, and gently press on your belly to see if your spleen feels enlarged.

Tests that may be done

• Blood tests to look for antibodies (proteins the body makes to fight EBV)
• A complete blood count (CBC) to check for changes in white blood cells
• A throat swab to rule out strep throat (a bacterial infection that needs different treatment)

What to expect at your appointment

If your symptoms and exam clearly point to mono, your doctor may not need a test. If tests are done, you may have to wait a few days for results. The doctor will explain what they find and advise you on how to manage symptoms.

Treatment

There is no cure for mono. Your body's immune system will fight the virus on its own. Treatment focuses on easing symptoms like fever, sore throat, and tiredness, and on helping you avoid complications.

Self-care at home

• Rest a lot. This is the most important part of recovery.
• Drink plenty of fluids to avoid dehydration and help your throat.
• Gargle with warm salt water (for older children and adults) to soothe a sore throat.
• Try using a humidifier at night to keep the throat moist.
• Ask your pharmacist or doctor about safe options for fever or pain relief — never take more than the recommended amount.

Medical treatments

In most cases, no medicine is needed. If throat swelling is very severe, a doctor may prescribe medicine to bring the swelling down. This is usually only for a short time. Antibiotics do not work against mono because it is caused by a virus. If you are given antibiotics for a bacterial infection like strep throat and you have mono, you may develop a rash. Always tell your doctor if you have mono.

When is surgery considered?

Surgery is very rarely needed for mono. If the spleen tears (ruptures) — a medical emergency — surgery may be required to stop internal bleeding. This is why it is vital to avoid rough sports and heavy lifting for several weeks after mono.

Living with this condition

Mono can make you feel very tired for a few weeks. It is okay to take time off from school, college, or work. Let friends and family help you with everyday tasks while you rest. If you are a student, talk to your tutor or student support office about catching up on work or missing exams.

Lifestyle tips

• Keep a regular sleep schedule and nap if you need to.
• Do not drink alcohol while you are recovering, because your liver may be affected.
• Avoid contact sports, lifting heavy objects, or any activity that pushes your body, especially in the first month.
• Return gradually to normal activities once you have more energy.

Diet and exercise

Eat soft, easy-to-swallow foods like soup, yogurt, mashed potatoes, and oatmeal. Drink water, broth, and herbal tea throughout the day. When you feel stronger, start with short, gentle walks and slowly build up. Stop if you feel too tired.

Mental health and emotional wellbeing

Being unwell and missing out on your usual routine can be frustrating and lonely. It is normal to feel low. Talk to people you trust about how you feel. If you notice signs of depression — such as feeling hopeless, losing interest, or sleeping too much — speak to a doctor or your local mental health support service.

Prevention

There is no vaccine for mono, and it is not always possible to avoid the virus. But you can reduce your risk by not sharing personal items that come into contact with saliva, such as drinking bottles, cups, cutlery, toothbrushes, or lip balm. It also helps to avoid close contact, such as kissing, with someone who has mono.

Vaccines

There is currently no vaccine to prevent mono.

Screening programmes

There is no routine screening test for mono. You should only be tested if you have symptoms and your doctor thinks it may be mono.

Complications

If left untreated

• Most people recover without any treatment. In rare cases, complications can happen, especially if you do not rest enough.
• An enlarged spleen, which could rupture if you return too quickly to heavy activity or contact sports.
• Liver inflammation (hepatitis), which may cause yellowing of the skin or eyes.
• Long-lasting tiredness that goes on for weeks or even months.

Long-term outlook

The outlook for mono is very good. Most symptoms go away within a few weeks, even though tiredness may stay longer. With enough rest, healthy eating, and time, your energy will return. Let your healthcare provider guide you through recovery.

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