It's associated with a nasty sore throat and chronic fatigue, and is far more common than you might think. Abi Jackson checks up on the facts...
Nobody likes a sore throat, and some can be particularly painful, especially when accompanied by horribly swollen glands and a raging fever - which can be tell-tale signs of dreaded glandular fever.
Caused by the Epstein-Barr virus (EBV), most people will be exposed to it during their lifetime - often during early childhood, when it might cause minimal symptoms, or even go totally unnoticed, and the body builds up immunity to it.
This isn't always the case though, and some - particularly teens and young adults - catch it later and experience a nasty bout of illness.
Here are eight things everybody should know about glandular fever...
YOU DON'T JUST CATCH IT FROM KISSING
It may be commonly known as the 'kissing disease', but that doesn't mean you only catch it from locking lips with somebody who's infected. "It's mainly spread through saliva, so kissing, coughing, sneezing, and sharing a glass or cutlery, are the easiest ways to catch the virus," says Dr Louise Read, a GP and advisor to Dr Morton's - the medical helpline. "It is, however, less easy to catch than the common cold."
IT CAN MAKE YOU FEEL REALLY UNWELL
Symptoms typically include swollen glands, a high temperature/fever, a horribly sore throat and fatigue.
How severe these things are can vary from person to person, but it can make you really poorly.
BUT YOU PROBABLY WON'T KNOW YOU'VE CAUGHT IT IMMEDIATELY
"The incubation period is four to eight weeks," Dr Read explains of the time frame between catching the infection and getting unwell.
"Symptoms usually settle after two to three weeks, but can last for many weeks or months," she adds.
THE FATIGUE CAN LINGER
"The tiredness associated with glandular fever can last for several months. Up to 50% of people with glandular fever can feel like this.
Frustratingly, the reasons for this are not known," says Read.
"It affects people in different ways; teenagers often have a tricky time as they're already dealing with the affects of puberty, exams and changes in their social relationships.
Interestingly, 10% of people diagnosed with chronic fatigue syndrome have had glandular fever previously."
YOU'LL NEED TO TAKE IT VERY EASY
Though complete bed rest isn't generally recommended these days (this can actually slow the recovery process), children and teens will need some time off school, and adults will need some time off work to get some decent rest - and then ease back into normal activities gently while your energy returns.
Staying well-hydrated is also important, "because the body needs more liquid when it has a fever," explains Read, along with good nourishment and general TLC.
Avoiding alcohol is also advised, due to a greater risk of liver damage while your body's fighting the infection.
BUT YOU PROBABLY WON'T NEED A PRESCRIPTION
"Antibiotics are usually not needed," says Read, as they're used to treat bacterial infections, not viruses.
However, if you develop a secondary problem such as a bacterial throat or lung infection, they may be required.
Paracetamol and ibuprofen can help relieve pain and fever, and gargling with a warm salt-water solution can help sore throats.
"Infections like pneumonia are recognised complications, but are fairly rare," says Read.
OTHER SERIOUS COMPLICATIONS CAN OCCUR
"About half of people with glandular fever get a swollen spleen, while one in 750 will end up in hospital with a ruptured (burst) spleen," says Read.
"For this reason, people are advised to avoid strenuous exercise for three to four weeks until their spleen has returned to normal size.
Other complications, like problems with the nerves, are also rare, affecting about one in 100 people with glandular fever."
A severely swollen throat can also result in difficulty swallowing for some people, who may end up needing a short stay in hospital.
YOU'LL NEED TO TAKE STEPS TO AVOID IT SPREADING
Once you've got symptoms and while they settle, it's sensible to take steps to avoid spreading the virus (like you'd do with a cold or flu; not sharing drinks, washing your hands or using a hand sanitizer as required, etc).
However, as Read notes, most people will already have been exposed to the virus at some point in their lives, or be carriers.
Plus "15-20% of people will feel well but continue to spread the virus.
The virus can reactivate in them but not cause any illness.
This is bad news for people around them who can catch it".
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