Creutzfeldt-Jakob disease (CJD)

14th May, 2021 • 8 min read

What is Creutzfeldt-Jakob disease (CJD)?

Creutzfeldt-Jakob disease (CJD) is a rare type of brain damage that’s thought to be caused by a unique type of protein – called a prion – that can infect animals and humans. If you’re infected by this prion, it usually causes brain damage that quickly gets worse.

CJD is sometimes also called ‘mad cow disease’, because, in 1996, a specific version of the condition – known as variant CJD – was found to be spread by eating infected beef. There are many other types of CJD and they’re caused by different things, including your genes or having surgery.

However, most of the time, there’s no clear reason why CJD happens.

There’s currently no cure for this disease, but if you develop it, there are treatments that can help to manage the symptoms.

Creutzfeldt-Jakob disease (CJD) symptoms

CJD affects your brain and nervous system, and as it progresses, it usually causes symptoms that impact your movement and brain function.

Some of these symptoms include:

  • memory loss
  • changes in your normal behaviour, personality and emotions
  • finding it hard to speak, like slurring
  • finding it hard to sleep well (
  • mood changes
  • seeing or hearing things that aren’t really there (
  • difficulty controlling your movements
  • blurred or double vision
  • loss of balance and coordination
  • shaking (tremors)

CJD may cause a type of

that progresses very quickly.

When to see a doctor about Creutzfeldt-Jakob disease (CJD)

CJD is a very rare disease and there are lots of conditions that are more common that can cause similar symptoms. Some of these are more serious than others, so see a doctor as soon as possible if you have any of the symptoms listed above.

If you have a family member who’s been diagnosed with CJD, discuss this with a doctor as it can occasionally run in families.

Go to an emergency department or call an ambulance immediately if you have any of these symptoms:

  • sudden dizziness or worsening dizziness, loss of balance or coordination
  • memory loss and a recent
    head injury
  • new weakness in your arms or legs
  • trouble speaking, like slurring
  • trouble understanding what other people are saying or feel confused
  • your face is drooping on one side
  • numbness or pins and needles on one side of your body
  • changes to your vision
  • fits (seizures)
  • a sudden, really bad headache

What causes Creutzfeldt-Jakob disease (CJD)?

CJD is a type of prion disease. Prions are proteins found in our bodies – it’s thought they change and act abnormally, multiplying and replacing normal proteins in your brain when you have the disease.

Over time, these prion infections destroy brain cells and create holes in the brain, so that it becomes sponge-like.

There are 4 main types of CJD:

Sporadic CJD

This is the most common type and usually affects people over 40 years old. It’s rare. The exact cause of sporadic CJD isn’t known, but it’s thought that a normal brain protein changes into an abnormal one, causing brain damage.

Familial CJD

Familial, or inherited (genetic) CJD is less common than sporadic CJD. It’s a genetic condition that can run in families and be inherited from a parent, or be caused by a new change (called a mutation) in a gene from birth.

The first symptoms usually don’t start until you’re 50. And around 1 in 2 people who develop familial CJD don’t have other family members with the condition. It’s also possible that not everyone who has the genetic change will develop symptoms.

Variant CJD

This type of CJD can affect younger people too. It’s thought to be caused by eating meat from cows infected by ‘mad cow disease’ (known as bovine spongiform encephalopathy or BSE).

It’s not known for sure but it’s thought that it may take more than 10 years from the time of infection for the symptoms of this type of CJD to appear.

Variant CJD was first identified in 1996 (it was first seen in the UK). But strict controls were put in place worldwide to prevent people from eating this infected meat, and variant CJD has since become rare.

Iatrogenic CJD

Iatrogenic (or acquired) CJD is where CJD is accidentally spread through medical or surgical treatment. It can be spread through certain types of brain surgery, tissue grafts and hormone treatment. But, it’s rare now due to changes in organ donation and surgical procedures.

It can take a long time (around 10 years on average) for the symptoms of iatrogenic CJD to develop after you’ve been infected.

How is Creutzfeldt-Jakob disease (CJD) diagnosed?

A doctor will usually ask you about your symptoms and examine you if they suspect you may have CJD. It’s likely you’ll need to see a specialist called a neurologist who will rule out other conditions and organise tests to look for signs of CJD. These may include:

  • an
  • an
  • a
    lumbar puncture
  • a
    blood test
    – a test for detecting variant CJD is currently being developed
  • a tonsil
    – a piece of tissue can be taken from your tonsils to test for variant CJD
  • a genetic test – to find out if your CJD could be inherited

While these tests are helpful, the only way to confirm you truly have CJD is to examine a sample of brain tissue by doing a brain biopsy. But this test can’t be done on someone who’s alive.

Creutzfeldt-Jakob disease (CJD) treatment

At the moment, there’s no cure for CJD, but clinical studies are looking into treatments for the future.

There are treatments that help with the symptoms and to keep you as comfortable as possible, for example:

  • a low mood (
    ) can be treated with
  • feeling agitated can be treated with sedatives, or tranquilisers
  • strong
    can help with pain
  • muscle jerks and shaking (tremors) can be treated with muscle relaxants

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how a chronic illness may affect your mental health

What can you expect if you have Creutzfeldt-Jakob disease (CJD)?

If you’re diagnosed with CJD, you may be treated by experts in a specialised centre with lots of support, as it’s a life-threatening condition. Your team might include neurologists, nurse specialists and psychologists to support you and your family.

Studies are now looking at a variety of drugs, so you might be invited to join a trial.

Dealing with CJD can be very difficult, so speak to a doctor if you’re finding it hard to cope. You can also contact a support group like the below for additional support:

Your health questions answered

How long can you live with Creutzfeldt-Jakob disease?

Most people diagnosed with CJD live for around 1 year after their symptoms start. If you have familial CJD, it takes a bit longer for the symptoms to progress – usually around 2 years.

Can you get CJD from eating beef?

You can get variant CJD from eating beef from a cow infected with ‘mad cow disease’ (known as bovine spongiform encephalopathy, or BSE). But, since the connection between variant CJD and BSE was first discovered, strict controls have stopped infected meat being eaten. The number of people with variant CJD is reducing and there are now very few cases.

How contagious is CJD?

In theory, CJD can be spread from a person who’s infected with it to another person, but this could only happen if someone came into contact with a contaminated injection, or if they ate brain or nervous tissue that was infected with CJD – but this isn’t likely. In the UK, there have been 4 cases where variant CJD has been spread through blood transfusions. But there have been no reports that sporadic CJD has been spread from one person to another through daily contact or by blood, sexual contact or airborne droplets.

Key takeaways

  • CJD is a rare type of brain damage thought to be caused by a unique protein called a prion
  • it causes progressive dementia and problems with movements
  • it has 4 main types: sporadic, familial, variant and iatrogenic
  • variant CJD is caused by eating meat from cows infected with ‘mad cow disease’
  • CJD can’t be cured, but treatment can help with the symptoms

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.