Glandular fever

What is glandular fever?

Glandular fever (which sometimes used to be known as "kissing disease") is a viral infection, mostly caused by the Epstein-Barr virus. The virus can be passed from person to person by close contact.

Glandular fever is known as infectious mononucleosis in the US and some other countries. This is because the infection often causes an increase in a particular white blood cell called a monocyte. It is sometimes known as "mono".

It can take up to seven weeks for the symptoms to develop after a person has first been infected with this virus. This is called the incubation period.

Symptoms of glandular fever (infectious mononucleosis)

Some people will have the glandular fever infection without knowing that they have it, or have mild symptoms that they assume is a normal cold.

One or more of the following symptoms commonly occur for about a week or so. Symptoms then usually gradually settle over another week.

Sore throat

The throat is often very sore, red and swollen. Tonsils may be enlarged and covered in pus. Glandular fever may be suspected if tonsillitis is severe and lasts longer than usual. Swallowing is often painful and saliva may pool in the mouth.

NB Tonsils being covered in pus does not mean this is a bacterial infection needing antibiotics. Pus is also caused by viral infections, such as glandular fever. Antibiotics are not usually necessary and can make symptoms worse.

Swollen glands

As the body's immune system fights off the virus, it causes swollen lymph nodes (glands). Any lymph gland in the body can be affected but the glands in the neck are usually the most prominent. They can become quite large and tender.

Flu-like symptoms

Like other viral infections, glandular fever often causes a high temperature (fever), muscle aches and headaches.

Malaise

A feeling of intense tiredness quite often develops with glandular fever.

Eye symptoms

A variety of symptoms of inflammation of the eyes, including conjunctivitis, can sometimes occur with glandular fever.

Enlarged spleen

The spleen is an organ under the ribs on the left side of the abdomen. It is part of the immune system. Like the lymph glands, it swells and can sometimes be felt below the ribs in people with glandular fever. Very occasionally, it causes mild pain in the upper left abdomen.

No symptoms

Many people become infected with this virus but do not develop symptoms. This is called a subclinical infection. This is more common in children.

Causes of glandular fever

Glandular fever is most often caused by the Epstein-Barr virus (EBV). In about 1 in 10 people with glandular fever, it is caused by a different virus, such as cytomegalovirus, adenovirus or human herpesvirus 6.

The virus infects the cells on the lining of the throat. The infection is then passed into the white blood cells before spreading through the lymphatic system. This is a series of glands (nodes) found throughout the body. The lymphatic system also includes certain organs such as the spleen.

Is glandular fever contagious?

Glandular fever is not particularly contagious. It is mainly spread through contact with saliva, eg, kissing, sharing cups, food and drinks, toothbrushes or cutlery.

Small children may be infected by chewing toys that have been contaminated with the virus. It can also be spread through sexual contact, blood transfusion and organ transplant.

The disease is contagious during the incubation period and while symptoms are present. Some people may remain contagious for up to 18 months after they have had the infection.

Who gets glandular fever?

Glandular fever can affect people of any age but is most commonly affects teenagers and young adults. The immune system makes antibodies during the infection. This then usually provides lifelong immunity for those who develop glandular fever. This means that it is rare to have more than one episode of glandular fever.

It is estimated that 95 out of 100 adults in the world have immunity to glandular fever. This means that they have had glandular fever in the past, even though many of them were unaware of it.

In the US, white teenagers are more than 30 times more likely than Black teenagers to develop symptoms of glandular fever. It is thought that glandular fever is more common in Black children who are therefore immune by the time they are teenagers.

How is glandular fever diagnosed?

The symptoms caused by glandular fever are similar to symptoms due to various other viruses. Therefore, it can be difficult to diagnose glandular fever just by being examined.

A blood test may therefore be done that can detect an antibody to the Epstein-Barr virus and confirm a glandular fever infection.

Glandular fever complications

Most people with glandular fever do not have any complications or rare symptoms. If complications do occur, they may include:

Damaged spleen

This is a serious complication of glandular fever but rare, occurring in about 1 in 100 cases. As described above, the spleen is an organ that sits in the upper left side of the abdomen, usually protected by the lower ribs. A swollen spleen is more delicate than normal and may protrude below the ribs.

The spleen normally reduces to its normal size after about three weeks. However, one study found that in 3 out of 19 people it took eight weeks.

A damaged spleen may occur if the left side of the chest or abdomen is injured. It is therefore usually advised to avoid contact sports, such as rugby, for eight weeks after having glandular fever.

Rash

A widespread, non-itchy red rash occurs in some people with glandular fever. This usually fades quickly. The rash can also be caused by giving antibiotics. Antibiotics are not useful in glandular fever as it is caused by a virus not by a bacteria.

Viral hepatitis

The Epstein-Barr virus commonly causes mild inflammation of the liver (acute viral hepatitis) which gets better by itself and often has no symptoms. About 1 in 20 people develop yellowing of the skin (mild jaundice). This also goes away without treatment in the vast majority of cases.

Malaise and depression

It is common to feel tired and low for the duration of the illness and for a week or so afterwards. About 1 in 10 people develop 'postviral fatigue' which can last longer and occasionally for several months.

Glandular fever treatment

There is no cure for glandular fever and no specific treatment is needed, as the immune system deals with the infection by itself. However:

Drink plenty of fluids

It is important to drink plenty of fluids. It is often tempting not to drink very much if it is painful to swallow. This can lead to mild lack of fluid in the body (dehydration), particularly if you also have a high temperature (fever).

Mild dehydration can make headaches and tiredness much worse. It can be worthwhile taking paracetamol or ibuprofen to ease pain, headache and fever.

Steroid medicines

Some studies have looked at the use of steroid medicines for people with glandular fever. The theory was that steroids help to reduce inflammation in various conditions and so may do so for glandular fever. However, the current advice is that steroids are more likely to suppress the immune system so should not be used.

Avoid contact

To prevent spread, it is important to avoid kissing and close body contact with other people to stop glandular fever spreading. It is also best not to share cups, towels, etc, whilst ill.

There is no need to miss any school with glandular fever, unless feeling too unwell to attend. Medical advice should be sought if any unusual, severe or unexplained symptoms develop.

Reduce alcohol intake

Glandular fever can cause a temporary inflammation of the liver. This means that drinking alcohol whilst having glandular fever can cause people to feel very unwell. It is therefore advised to avoid alcohol completely during glandular fever.

Are antibiotics needed?

Antibiotic medicines are not used, as glandular fever is caused by a virus. Antibiotics do not kill viruses.

How long does glandular fever last?

A full recovery is usual within a couple of weeks. Some people have a lingering tiredness that lasts a few weeks. It is rare to have glandular fever a second time.