Pathogen Safety Data Sheets: Infectious Substances – Echinococcus multilocularis

PATHOGEN SAFETY DATA SHEET - INFECTIOUS SUBSTANCES

SECTION I - INFECTIOUS AGENT

NAME: Echinococcus multilocularis

SYNONYM OR CROSS REFERENCE: Alveolar hydatid disease, Multilocular echinococcosis

CHARACTERISTICS: Cestode, tapeworm consisting of 3 to 5 segments, usually 1.2-3.7 mm long; hydatid cyst buds exogenously to form a multilocular cyst; parasite infiltrate host tissues like a malignancy by external proliferation of the germinal membrane to form new cysts

SECTION II - HEALTH HAZARD

PATHOGENICITY: Disease depends on the size and location of the larval masses; cysts grow slowly in humans (abnormal host), since a person may be infected for 30 years before symptoms appear; primary lesion in alveolar hydatid disease is always the liver and contiguous organs to produce chronic space-occupying lesions; pieces of the germinal membrane may metastasize to infect the brain, lungs and mediastinum; disease is often fatal if not treated

EPIDEMIOLOGY: Distribution is limited to areas in the Northern Hemisphere: central Europe, Commonwealth of Independent States, northern Japan, China, India, Alaska, Canada and north-central USA; disease usually diagnosed in adults; high risk individuals include hunters and fur traders

HOST RANGE: Humans are abnormal host; definitive host is foxes, but wolves, coyotes, dogs and cats have been infected; intermediate host includes voles, lemmings, shrews and mice

INFECTIOUS DOSE: Not known

MODE OF TRANSMISSION: Ingestion of infected eggs passed in feces of infected Canidae and Felidae; fecally soiled dog hair, harness and environmental fomites serve as vehicles of infection; vegetables and water contaminated with the parasites eggs

INCUBATION PERIOD: Variable, from months to years, depending on the site and number of cysts

COMMUNICABILITY: Not directly transmitted from person-to-person

SECTION III - DISSEMINATION

RESERVOIR: Adult tapeworm found in foxes, wolves, coyotes, dogs and cats; intermediate hosts are voles, shrews, lemmings and mice; commonly maintained in nature in fox-rodent cycle

ZOONOSIS: Yes - infection is acquired from infected Canidae and Felidae

VECTORS: coprophagic flies may serve as a mechanical vector of eggs

SECTION IV - VIABILITY

DRUG SUSCEPTIBILITY: Sensitive to mebendazole, albendazole, praziquantel

SUSCEPTIBILITY TO DISINFECTANTS: Susceptible to 1% sodium hypochlorite, 2% glutaraldehyde

PHYSICAL INACTIVATION: Sensitive to heat

SURVIVAL OUTSIDE HOST: Cysts can survive cold climate

SECTION V - MEDICAL

SURVEILLANCE: Monitor for symptoms; confirm by serology and microscopic examination of tissues for cysts

FIRST AlD/TREATMENT: radical surgery and / or administer appropriate drug therapy

IMMUNIZATION: None available

PROPHYLAXIS: Praziquantel may be administered in case of accident

SECTION VI - LABORATORY HAZARDS

LABORATORY-ACQUIRED INFECTIONS: None reported to date

SOURCES/SPECIMENS: Tissue biopsy specimens, stool

PRIMARY HAZARDS: Ingestion; droplet exposure of mucous membrane, percutaneous

SPECIAL HAZARDS: Contact with fecal matter from experimentally infected animals

SECTION VII - RECOMMENDED PRECAUTIONS

CONTAINMENT REQUIREMENTS: Biosafety level 2 practices and containment equipment for all activities involving the infective stages of the parasite and infectious body fluids or tissues

PROTECTIVE CLOTHING: Laboratory coat; gloves when skin contact with infectious materials is unavoidable

OTHER PRECAUTIONS: Work with this parasite (gravid segments) should be conducted in a biosafety cabinet or its equivalent

SECTION VIII - HANDLING INFORMATION

SPILLS: Allow aerosols to settle; wearing protective clothing, gently cover the spill with absorbent paper towel and apply 1% sodium hypochlorite starting at the perimeter and working towards the centre; allow sufficient contact time (30 min) before clean up

DI8POSAL: Decontaminate all wastes before disposal; steam sterilization, chemical disinfection, incineration

STORAGE: In sealed containers that are appropriately labelled

SECTION IX - MISCELLANEOUS INFORMATION

Date prepared: January, 2001

Prepared by: Office of Laboratory Security, PHAC

Although the information, opinions and recommendations contained in this Material Safety Data Sheet are compiled from sources believed to be reliable, we accept no responsibility for the accuracy, sufficiency, or reliability or for any loss or injury resulting from the use of the information. Newly discovered hazards are frequent and this information may not be completely up to date.

Copyright ©
Health Canada, 2001