Creutzfeldt-Jakob Disease

Frequently asked questions about CJD

1. Can you catch CJD from someone?
   CJD and other human prion diseases are not believed to spread by close or casual person-to-person contact or by the airborne/respiratory route. However, transmission can occur during invasive medical interventions. It is sensible for anyone who might be exposed to the blood of another person to wear gloves.
2. How can we be sure that the diagnosis of CJD is the correct one?
   It should be emphasized that a definite diagnosis of any form of CJD can only be given by brain tissue examination after death. Each individual case of CJD can be assigned to one of three subtypes: sporadic, genetic or acquired. The considerations for diagnosis vary depending on the subtype. In genetic prion diseases, the diagnosis depends on development of particular neurological symptoms and the identification of a PRNP gene mutation by genetic analysis. Iatrogenic CJD is diagnosed on the basis of a confirmed diagnosis of CJD in someone who had a relevant medical exposure. Variant CJD is diagnosed by distinctive features seen on post-mortem examination of the brain.
3. Is the blood supply safe from CJD?
   Since donors cannot, at present, be tested for early biological indicators of CJD, nor can blood donations be tested for the removal of the prion agent after processing, and considering vCJD has been shown to be transmissible through blood transfusion, the Canadian Blood Services has developed policies with regards to CJD and blood donation. Canadian Blood Services deferral policies are available by contacting Canadian Blood Services at 1-888-2donate.
4. Is there a risk in contracting CJD from organ transplant surgery?
   The risk of contracting CJD from organ transplants is uncertain, but believed to be small. Unfortunately, a transplant usually has to be done before a full post-mortem examination of the donor can be completed, so this risk cannot be completely eliminated. However, if a potential donor is suspected of having CJD their tissues and organs would not be used for transplantation. Note also that there is a risk of infection in any transplant.
5. Is the person with CJD in pain?
   Neurological examination and the EEG of people in the later stages of CJD indicate that they lose awareness of their condition as the disease progresses. In the early stages, however, patients with CJD can develop marked fear, which can be very distressing and is probably associated with visual hallucinations. They may feel discomfort and some of the symptoms of the disease - such as myoclonus, sudden jerking of the limbs - are distressing for caregivers to witness. There are medications which can relieve the symptoms and make the person more comfortable. In vCJD dysesthesia, an unpleasant abnormal sensations to normal stimuli, has been described.
6. Is a post-mortem examination necessary in CJD?
   Post-mortem examination is not compulsory when CJD is suspected - the doctor requires the permission of the next of kin. However, because it is the only way, at the moment, to definitively diagnose CJD, this knowledge is often very helpful for families. The autopsy findings and any donated tissues will also be very beneficial to support research into the disease.
7. Will there be many more cases of variant CJD?
   As of April 3, 2007, there were 202 cases of vCJD worldwide. If the disease comes from exposure to infected beef products prior to the ban on specified offal in human food in 1989, as is now widely accepted, then there could be more cases if the incubation period is very long. However, without knowing the exact circumstances of infection, or who is most at risk and why, it is currently impossible to predict how many more cases of vCJD there will be.
8. What is being done to protect us from CJD?
   At present there is no specific way of protecting people from developing sporadic or familial CJD. Destroying surgical instruments that have been used on certain tissues of people with CJD and not using their organs for transplant guards against iatrogenic CJD. There have also been recent measures taken by the Canadian Blood Services for safeguarding the blood supply from variant CJD.

Acknowledgement: The Canadian Creutzfeldt-Jakob Disease Surveillance gratefully acknowledges the contribution and participation of Canadian families and physicians.