Some of these beliefs cause real distress to families, so it is worth taking them one at a time.
Can I catch it from the person I am caring for?
No. CJD is not spread between people by normal contact or through contamination of the surroundings. Hugging, holding hands, sharing a room, doing the washing and helping someone eat carry no risk of passing it on.
Hospital staff do use careful rules for a small number of situations, such as brain surgery, because prions survive ordinary sterilising. Those rules apply to instruments and clinical procedures.
There is more on this, including burial and cremation, on our page is CJD contagious.
Did this come from eating beef?
Almost certainly not. Only one form, variant CJD, is linked to eating beef from cattle with bovine spongiform encephalopathy, often called mad cow disease. That form is very rare, and the cattle feeding practices behind it have changed.
The common form has no known cause.
Is it the same thing as mad cow disease?
They are related but separate. Bovine spongiform encephalopathy is the disease in cattle. Variant CJD is the human illness linked to it. Most people with CJD have neither.
Does it always run in families?
No. Most cases are sporadic, which means no cause has been found and nothing was inherited. Health authorities put that at roughly 85 to 93 of every 100 cases.
Inherited forms are a small share, somewhere between about 5 and 15 in every 100 depending on the country and how cases are counted. A smaller group again followed contact with prions during medical care in the past.
If you are wondering about your own family, a genetic counsellor is the person to ask, and that conversation comes before any test. Choosing not to be tested is a valid choice.
Is it so rare that nobody is keeping track?
It is rare, and it is counted. About 1 to 2 people in a million are diagnosed each year. In Canada, 90 people were diagnosed in 2022, and about 9 in 10 of those diagnosed are aged 45 to 85.
Doctors in Canada must report a suspected case to their local public health authority, and are strongly encouraged to tell the national surveillance system as well. That system can be reached on 1-888-489-2999 or at cjdsurveillance@phac-aspc.gc.ca. Other countries have their own units.
Is there really nothing that can be done?
There is no medicine that stops the disease, and that is the hard part of the truth. There is a great deal that can be done for comfort.
Jerky movements, pain, anxiety, poor sleep and difficulty swallowing can all be treated. Nursing help, equipment and a palliative care team brought in early make a difference, and asking for that team is something a family can do straight away.
Our page on progression and outlook goes through what usually happens, and the group of conditions is listed on our diseases page, including kuru.