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SECTION I - INFECTIOUS AGENT
NAME: Scrapie agent (may be applied to Chronic Wasting Disease)
SYNONYM OR CROSS REFERENCE: Spongiform encephalopathy, Chronic infectious neuropathic agent (CHINA).
CHARACTERISTICS: Filterable, self-replicating, slow infectious pathogen; proteinaceous infectious particles
("prion").
SECTION II - HEALTH HAZARD
PATHOGENICITY: Chronic, fatal ataxia of deer, elk, sheep and occasionally goats; associated with BSE
of cows in United Kingdom.
EPIDEMIOLOGY: Widespread distribution in Europe, Asia and America.
HOST RANGE: Wild ruminants (Chronic Wasting Disease); sheep, goats (Scrapie); transmissible to mice, monkeys
and cattle.
INFECTIOUS DOSE: Unknown; 40,000 fold greater efficiency of establishing experimental infection in mice
by intracerebral inoculation, compared with the oral route.
MODE OF TRANSMISSION: Transmitted from ewes to lambs, placenta is infectious; may spread laterally from
naturally infected to uninfected animals; no evidence of transmission to occupationally exposed humans involving
trauma with scrapie tissues or from consumption of scrapie infected sheep; no evidence for transmission of chronic
wasting disease from wild ruminants to humans; transmission to cows in UK through addition of sheep offal to feed;
practice has ceased however, consumption of infected meat by humans has been associated with characteristic disease.
INCUBATION PERIOD: Up to 1 year.
COMMUNICABILITY: No current evidence of transmission to humans.
SECTION III - DISSEMINATION
RESERVOIR: Infected sheep, goats (Scrapie); Infected elk, deer (Chronic Wasting Disease)
ZOONOSIS: No evidence to support hypothesis that consumption of scrapie infected sheep might result in encephalopathy
in humans; ingestion of scrapie contaminated food by cattle and resultant Bovine Spongiforin encephalopathy (BSE)
may represent potential for transmission to humans.
VECTORS: None
SECTION IV - VIABILITY
DRUG SUSCEPTIBILITY: N/A
SUSCEPTIBILITY TO DISINFECTANTS: Resistance to commonly used disinfectants is well recognized formaldehyde,
glutaraldehyde, ethanol and iodine. Chlorine has been reported to be only partially effective. Disinfection should
be carried out using IN sodium hydroxide at room temperature for 1 hour or >3M GdnHCI at 55o C for
25 min.
PHYSICAL INACTIVATION: Resistant to UV and ionizing radiation, ultrasonication, nucleases, boiling, heat.
Autoclaving for I hour at 132o C is recommended for effective inactivation.
SURVIVAL OUTSIDE HOST: Survives well outside of host.
SECTION V - MEDICAL
SURVEILLANCE: Sheep or wild ruminants - monitor for clinical signs - diagnosis based on histopathological
findings, transmission to animals from biopsy specimens.
FIRST AID/TREATMENT: No specific treatment.
IMMUNIZATION: None
PROPHYLAXIS: None
SECTION VI - LABORATORY HAZARDS
LABORATORY-ACQUIRED INFECTIONS: No cases of infections with spongiform encephalopathies in occupationally
exposed persons (biologists, hunters, lab workers, butchers, shepherds, abattoir workers,).
SOURCES/SPECIMENS: Infected animals and tissues - brain, CNS, placenta.
PRIMARY HAZARDS: Accidental parenteral inoculation; risk from aerosols, droplets, and exposure of intact
skin, gastric and mucous membranes is not known.
SPECIAL HAZARDS: None
SECTION VII - RECOMMENDED PRECAUTIONS
CONT NT REQUIREMENTS: Biosafety level 2 practices, containment equipment and facilities when working
with this agent.
PROTECTIVE CLOTHING: Laboratory coat; gloves when contact with infectious materials is unavoidable.
OTHER PRECAUTIONS: None
SECTION VIII - HANDLING INFORMATION
SPILLS: Allow aerosols to settle; wearing protective clothing, gently cover spill with paper towel and
apply IN sodium hydroxide, starting at perimeter and working towards the center- allow sufficient contact time
(1 hour) before clean up.
DISPOSAL: Decontaminate before disposal; steam sterilization at 132o C for 1 hour, disinfection
with sodium hydroxide, incineration.
STORAGE: In sealed containers that are appropriately labeled.
Date prepared: October 11, 1997 Prepared by: Canadian Office of Biosafety.
Information edited by the Colorado State University Office of Biosafety; June 16, 1998.
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