Related Information
What is Creutzfeldt-Jakob disease (CJD)?
Creutzfeldt-Jakob disease is the most common human prion disease. Prion diseases are a group of rare brain and nervous system diseases that affect humans and some kinds of animals. Prion diseases are not caused by germs (i.e., viruses, bacteria). Instead, they are thought to result if normal brain proteins fold into abnormal forms. In affected people, clumps of these prion proteins cause brain damage and death.
CJD occurs worldwide in about one to two persons per million each year. In Washington State it affects about 12 people annually.
What causes CJD?
Most cases of CJD (~85%) occur in persons over 55 years old for unknown reasons. This type of CJD is called “sporadic” CJD. In some cases (10–15%), there is a genetic cause for CJD. Very rarely, CJD has been spread through contaminated neurosurgical instruments, dura mater or corneal grafts, or human-derived hormone therapies (no longer in use).
Another form of CJD, called variant CJD or vCJD, has affected more than 225 people worldwide. Most of those affected were 15–55 years old and lived in the United Kingdom during an epidemic of “mad cow disease” that occurred from 1980–1996. Mad cow disease is a cattle prion disease also known as bovine spongioform encephalopathy (BSE). vCJD is associated with eating products from BSE-affected cattle. There have not been any vCJD patients who got the disease in the United States. There are now many food safety measures in place to prevent BSE in cattle and to protect the food supply.
CJD is not spread from person to person by kissing, hugging or other close contact.
What are the symptoms of CJD?
People with CJD develop dementia and quickly deteriorate mentally. Involuntary twitching, rigid or spasming muscles, lack of coordination and balance, and visual problems are also common symptoms. CJD always leads to death, usually within one year of first symptoms.
How is CJD diagnosed?
Symptoms, family history, a lab test, and brain tests such as EEGs and MRIs can suggest to healthcare providers that a patient may have CJD. Recently, a spinal fluid screening test called the RT-QuIC has been made available. This screening test is very accurate and is believed to detect 92% of true prion cases. However, the definite diagnosis of CJD requires testing of brain tissue, which typically does not occur until after the patient has died. When a person has an illness that could be CJD, it is important that the person's family talk to their healthcare provider about getting a clear diagnosis after their loved one's death. An autopsy to confirm the diagnosis of CJD can be arranged through the National Prion Disease Pathology Surveillance Center free of charge.
How is CJD treated?
There is no treatment for CJD. The goal of care is to make the patient comfortable before death.
To support patients' families, the CJD Foundation operates a national toll-free line at (800) 659-1991.
Chronic Wasting Disease (CWD)
What is Chronic Wasting Disease?
Chronic wasting disease (CWD) is a prion disease that affects farmed and free-ranging cervids such as deer, elk, reindeer, and moose. CWD has been found in many states in the U.S., including Washington. CWD is fatal in animals and poses a serious threat to deer and elk populations in areas where it is found.
Signs and symptoms of CWD in animals
Signs in animals can include drastic weight loss (wasting), stumbling, listlessness, lack of fear of people, and other neurologic symptoms at the end stages of the disease. Most animals with CWD will not look sick because of the prolonged incubation period. If you observe a sick or dead animal while hunting or recreating, report it using the Report Sick, Injured or Dead Animals to WDFW form.
What are the human health risks of CWD?
To date, there have been no reported cases of CWD infection in people. There is no conclusive evidence that CWD can naturally infect people. However, some laboratory studies have suggested transmission could be possible and would most likely occur through ingestion of meat or organs from an infected animal. If CWD could spread to people, it would most likely be through eating infected deer or elk. Cooking does not remove or inactivate the prions in the meat or organs. Read more about CWD.
Recommendations for hunters
Hunters and others must consider many factors when deciding whether to eat meat from deer, elk, and moose harvested or salvaged (roadkill) from areas with CWD, including the level of risk they are willing to accept. The Washington Department of Fish & Wildlife (WDFW) has information available on where CWD has been found in the state and whether testing of a hunter-harvested animal is required.
To reduce disease risks, hunters should always take the following precautions:
- Do not shoot, handle, or eat meat or organs from animals that look sick or are acting strangely. Consider that roadkill might not have been healthy when accidentally killed by a motor vehicle.
- Use clean, sharp knives for field dressing and butchering. Do not use household knives or other kitchen utensils for field dressing.
- Wear eye protection and rubber, nitrile, or latex gloves when handling carcasses or meat.
- Avoid direct (bare skin) contact with fluid, organs, or other tissues from the animal.
- Don’t feed dogs (or other animals) raw meat or other parts of the carcass.
- Wash hands as soon as possible after dressing or handling a carcass with soap and water.
- Clean all tools and reusable gloves with a disinfectant, like dilute bleach.
- Thoroughly cook meat from any animal.
When hunting in an area with CWD, hunters should take these additional precautions:
- Do not touch or eat meat or organs from animals that were sick. It might be difficult to tell whether an animal found dead (e.g., roadkill) was sick prior to its death. It’s important to follow the steps below to protect your health when handling any animal carcasses.
- Minimize how much you handle the organs of the animal, particularly the brain or spinal cord tissues.
- Disinfect processing tools by soaking them in a solution of water and 40% household bleach for a minimum of 5 minutes. Check the label of the bleach container to make sure it has at least 2% free chlorine.
- Check state wildlife and public health guidance to see whether testing of animals is recommended or required. Current requirements for Washington are available from the WDFW. Recommendations vary by state, but information about testing is available from many state wildlife agencies.
- Strongly consider having the deer, elk, or moose tested for CWD before you eat the meat.
- If you have your deer, elk, or moose commercially processed, consider asking that your animal be processed individually so that you can easily identify and discard meat if you are notified that the animal tested positive for CWD.
- If your animal tests positive for CWD, do not eat meat or organs from that animal. Inform anyone to whom you gave meat of the positive result and recommendation to not consume any part of the animal.
- Safely discard carcasses and meat from positive animals. Since tissues from CWD-positive animals can contaminate the environment and infect other deer, elk, or moose, do not dispose of infected materials on the landscape. Contact DFW with questions about disposal by calling 360-902-2515 or emailing CWD@dfw.wa.gov.
If you have questions about CWD and human health, contact your local health jurisdiction.
More CWD Resources: