Human Prion Diseases
Prion
diseases, also known as transmissible spongiform
encephalopathies (TSEs), are rare, fatal neurodegenerative
diseases of animals and humans. The term prion is derived
from the phrase “proteinaceous infectious particles.” With TSE, normal cellular prion proteins fold into abnormal,
pathologic forms.
In humans, the most common prion disease,
sporadic Creutzfeldt-Jakob disease (sCJD), occurs worldwide
and affects one to two people per million population per
year. The risk increases in people over 50 years of age and
is higher among whites. Approximately 85% of CJD cases are
sporadic (sCJD) and 15% are inherited. Rarely, CJD has been
transmitted iatrogenically through the use of contaminated
neurosurgical instruments, human-derived growth hormone, or
dura mater or corneal grafts.
Sporadic CJD is
characterized by rapidly progressive dementia combined with
neurologic manifestations and death occurs within one year
of onset of symptoms. Less common human prion diseases
include Gerstmann-Sträussler-Scheinker syndrome (GSS) and
fatal familial insomnia (FFI).
The prion diseases that
affect humans and animals are different. Animal prion
diseases include bovine spongiform encephalopathy (BSE, “mad
cow disease”) in cattle, scrapie in sheep, chronic wasting
disease in deer and elk, and transmissible mink
encephalopathy.
In 1996, a new
variant of CJD (vCJD) was recognized in people living in the
United Kingdom (UK). Unlike other human prion diseases,
vCJD is associated with consumption of cattle that are
infected with bovine spongiform encephalopathy (BSE, “mad
cow disease”). As of November 2007, more than 200 cases of
vCJD have been reported worldwide, mostly in the UK. To
date, no cases of vCJD have been acquired in the United
States.
Human Prion Disease in Washington
State
Between three and nine CJD cases are reported annually statewide.
Prior to 2005, DOH used death certificate review to identify
reports of human prion diseases, however less than half had
undergone an autopsy to collect brain tissue for a confirmed
laboratory diagnosis.
To improve knowledge about human prion diseases, Washington’s local and state public health
departments, in collaboration with the Centers for Disease
Control and Prevention and the National Prion Disease
Pathology Surveillance Center, are working to increase the
recognition and reporting of suspected human prion disease.
Purpose of Reporting and
Surveillance
-
To
monitor trends in the epidemiology of human prion
diseases in Washington State.
-
To
maximize laboratory confirmation of suspected cases and
promote awareness of available resources.
-
To
detect the emergence of variant Creutzfeldt-Jakob
Disease (vCJD) or novel prion diseases in the United
States.
-
To
prevent potential iatrogenic transmission.
Legal Reporting Requirements
Human
prion diseases are reportable as rare diseases of public
health significance.
-
Healthcare providers: immediately notifiable to local
health jurisdiction
-
Hospitals: immediately notifiable to local health
jurisdiction
-
Laboratories: no requirements for reporting
-
Local health jurisdictions: immediately notifiable to
DOH Communicable Disease Epidemiology: 1-877-539-4344
Last
update
November 2007 |
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