Promoting and protecting the health and safety of all Idahoans

Creutzfeldt-Jakob Disease

Creutzfeldt-Jakob Disease is a degenerative brain disease that has been recognized since the 1920s. It is a human prion (infectious protein) disease that progresses rapidly and is always fatal, usually within one year from onset of illness. 

CJD is not transmissible from person-to-person through ordinary contact, but it can be transmitted from one person to another by contaminated instruments used for brain surgery or by transplant of infected tissue. There is no known environmental trigger for development of CJD. For more information on CJD, see and the links under “Where can I get more information about CJD?”
Note: CJD is different from variant CJD (vCJD) which is linked to “Mad Cow disease” in cattle and caused an outbreak in Europe. For more information on variant CJD see:
Creutzfeldt-Jakob Disease (CJD) in Idaho: 1985–2011

CJD was not added to the list of legally reportable diseases in Idaho until 2004. (For more information about reportable diseases please see the Idaho Reportable Disease Summary website.) Prior to that, information on the number of cases of CJD was based only on information reported on death certificates. The annual number of reported CJD deaths in Idaho during 1985—2011 ranged from zero to seven. CJD deaths were reported from 22 Idaho counties. During 1985 through 2011, only 18 (43%) of 42 persons with CJD on their death certificate had received an autopsy. Although a clinical diagnosis of CJD based on symptoms and physical examination is reportable, autopsy is the only way to confirm the diagnosis. 

Creutzfeldt-Jakob Disease (CJD) Deaths among Idaho Residents: 19852011

Year Number of Deaths Counties
1985 0  
1986 3 Bonneville, Gem, Washington
1987 0  
1988 3 Ada, Canyon, Twin Falls
1989 2 Minnidoka, Nez Perce
1990 0  
1991 0  
1992 0  
1993 3 Bonner, Canyon, Minnidoka
1994 2 Ada, Gooding
1995 2 Ada, Twin Falls
1996 2 Bannock, Canyon
1997 1 Payette
1998 1 Idaho
1999 1 Ada
2000 2 Canyon, Owyhee
2001 1 Elmore
2002 0  
2003 1 Kootenai
2004 1 Franklin
2005 7 Bear Lake, Benewah, Caribou, Minidoka, Twin Falls (3)
2006 0  
2007 0  
2008 2 Ada, Lemhi
2009 3 Jerome, Kootenai, Twin Falls
2010 2 Kootenai, Bonner
2011 3 Ada (2), Washington
Total 1985-2011 42  

†Number of deaths reported on death certificate as CJD, 1985—2011. Idaho resident deaths might have occurred in Idaho or out of state. ICD-9 code used from 1985—1998: 046.1; ICD-10 code used from 1999—2011: A81.0 (Creutzfeldt-Jakob Disease) and B94.8 (Sequelae of other specified infectious and parasitic diseases and Creutzfeldt-Jakob Disease is specified).

CJD counts published based on year of death might differ from counts published based on year of report.

‡Data from 2011 are preliminary.

Source: Bureau of Vital Records and Health Statistics, Idaho Department of Health and Welfare (1/2011).

CJD in Idaho: 2005

In late July 2005, South Central District Health and the Idaho Dept. of Health and Welfare, Office of Epidemiology and Food Protection (now Bureau of Communicable Disease Prevention), began investigating reports of possible CJD cases due to a concern about an increase in this disease in southcentral Idaho. All five patients were over 55 years of age and all are deceased. The investigation included a review of medical records and interviews with treating physicians. A survey for information on dietary habits, residence, travel, occupation, surgeries, and other life experiences also was conducted through interviews with family members. No common travel, occupation, place of employment, surgical procedures, medications, supplements, or unusual food history were identified. Autopsies were done for three of the five patients. A diagnosis of CJD (not variant CJD) was confirmed in two autopsied patients and the autopsy results for the third patient were not consistent with CJD. The illness in the two patients who were not autopsied did not meet the case definition for probable or possible CJD. No explanation for the increase in reports was found, but in 2006 and 2007, no cases of CJD were reported from the area, suggesting the cases may have coincidentally occurred in the same time frame.