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Glandular fever information

Glandular fever is an infectious condition. Its medical term is ‘infectious mononucleosis’. It can occur at any age, but is most common in teenagers and young adults. It used to be called the ‘kissing disease’ as this is one of the ways it can be spread.

What causes glandular fever?

Glandular fever is caused by the Epstein-Barr virus (EBV), which 90 per cent of adults have in their body. EBV infections usually don’t cause problems but when they happen in teenagers and young adults they can develop into glandular fever.

The incubation period between catching the virus and developing symptoms can be two to four weeks. The virus is most infectious when combined with a high temperature.

Glandular fever is spread through saliva (spit). The most common ways are through kissing, sneezes and coughs, or sharing cutlery, glasses and cups.

What are the signs and symptoms of glandular fever?

About half of all teenagers and young adults who come into contact with the virus will develop common symptoms. These include:

  • Sore throat
  • Muscle aches
  • Swollen glands in the neck, armpits and groin
  • Loss of appetite
  • Weight loss
  • Extreme tiredness
  • Feeling generally unwell with a high temperature

A person will often have cold or flu like symptoms for a couple of weeks beforehand.

How is glandular fever normally diagnosed?

Glandular fever is diagnosed by a blood test.

How is glandular fever treated?

Unfortunately, there is no cure and because glandular fever is caused by a virus, antibiotics are not effective.

Instead, you will be advised how best to treat the symptoms to ensure the child is as comfortable as possible.

Make sure the child is drinking plenty of water, especially if they have a high temperature, to reduce the risk of dehydration. Also give paracetamol to help relieve any pain and reduce the child’s temperature.

Recovery can be a slow process. It is important for the child to rest when they are feeling tired or running a fever. Also, as the child begins to feel better, they should increase their activity only gradually - doing a little more each day.

For most teenagers and young adults, recovery is a slow process but they will be able to gradually increase their activity levels over time. Stressful situations can make recovery slower, so if the child is facing exams you should talk to their teacher.

Glandular fever has been reported as the trigger for a condition called chronic fatigue syndrome (also called ME) but this is not the case for everyone.

What happens next?

For most teenagers and young adults, recovery is a slow process but they will be able to gradually increase activity over time without complications.

It is usually recommended though that anyone who has had glandular fever should not take part in strenuous sports for at least a month after the infection, or sometimes longer. This is to allow the spleen to recover because if it is swollen, it could be damaged easily. This means the child may need to avoid contact sports like rugby and football. Your doctor will be able to give you more details on this.

Sometimes complications can happen but they are very rare. These include pneumonia, encephalitis (inflammation of the brain), hepatitis and some blood abnormalities. If the initial diagnosis was uncertain and a child was prescribed an antibiotic such as ampicillin or amoxicillin, they can develop quite extensive drug rash if they do have underlying glandular fever.  

It is estimated that around one in ten people who have had glandular fever will go on to develop chronic fatigue syndrome – a condition which makes you tired and weak for a long time.

After having the disease, a person will develop some immunity to it. However because the virus remains dormant in the body, it is possible that later in life the virus may reactivate.

Research is underway to develop a vaccine to protect against the Epstein-Barr virus.

More information

You can learn more about our clinical specialties by visiting infectious disease.

Last reviewed by Great Ormond Street Hospital: 22 July 2011