MATERIAL SAFETY DATA SHEET - INFECTIOUS SUBSTANCES

SECTION I - INFECTIOUS AGENT

NAME: Rickettsia prowazekii, Rickettsia canadensis (Formerly R. canada)

SYNONYM OR CROSS REFERENCE: Louse-borne typhus fever, Epidemic typhus, Typhus exanthematicus, Classical typhus fever, Brill-zinsser disease

CHARACTERISTICS: Pleomorphic, gram-negative bacterium, obligate intracellular

SECTION II - HEALTH HAZARD

PATHOGENICITY: Variable onset, often sudden with headache, chills, fever, prostration, and general pains; macular eruption on the 5 and 6th day on upper trunk and spreading to entire body (except face, palms or soles); pronounced toxemia; disease terminates approximately 2 weeks after onset of fever; case fatality rate from 10-40% in absence of treatment; may recrudesce years later as Brill-Zissner disease

EPIDEMIOLOGY: Occurs in areas of poor hygiene and that are louse-infected; endemic foci in mountainous regions of Central and South America, in Africa and Asia; in USA, last louse-borne outbreak was in 1921 and now exists as a zoonosis of flying squirrels (33 infections between 1976 and 1984)

HOST RANGE: Humans, squirrels

INFECTIOUS DOSE: <10 organisms

MODE OF TRANSMISSION: The body louse is infected by feeding on the blood of a patient with acute typhus fever; infected lice excrete rickettsiae in their feces and defecate at time of feeding; man is infected by rubbing feces or crushed lice into the bite or into superficial abrasions; inhalation of infective louse feces from dust; transmission from squirrel may be the bite of squirrel flea

INCUBATION PERIOD: From 1 to 2 weeks, commonly 12 days

COMMUNICABILITY: Not directly transmitted from person-to-person; patients are infective for lice during the febrile illness and possibly for 2 to 3 days after temperature returns to normal; louse is infective within 2 to 6 days after infected meal (infective earlier if crushed)

SECTION III - DISSEMINATION

RESERVOIR: Humans maintain the infection during inter-epidemic periods; importance of flying squirrel has not yet been demonstrated

ZOONOSIS: Possibly by flying squirrel

VECTORS: Body louse - Pediculus humanus

SECTION IV - VIABILITY

DRUG SUSCEPTIBILITY: Sensitive to tetracyclines, chloramphenicol doxycycline

SUSCEPTIBILITY TO DISINFECTANTS: Susceptible to 1% sodium hypochlorite, 70% ethanol, glutaraldehyde, formaldehyde

PHYSICAL INACTIVATION: Susceptible to moist heat (121° C for at least 15 min) and dry heat (160-170° C for at least 1 hour)

SURVIVAL OUTSIDE HOST: Rickettsia may remain viable in louse fecal material and the dead louse for weeks

SECTION V - MEDICAL

SURVEILLANCE: All immediate contacts should be observed for 2 weeks for symptoms of illness; R. prowazekkii is cross reactive with R. typhi

FIRST AID/TREATMENT: For seriously ill patient with possible typhus, antibiotic therapy should begin without waiting for laboratory confirmation; treatment with chloramphenicol or tetracyclines

IMMUNIZATION: No commercially available vaccine for use (persons entering high endemic areas are immunized eg. military); live vaccine prepared from the attenuated strain E of R. prowazekii has shown promise

PROPHYLAXIS: Use of residual insecticide applied to clothing and treatment of hair for louse eggs

SECTION VI - LABORATORY HAZARDS

LABORATORY-ACQUIRED INFECTIONS: 56 reported infections of epidemic typhus up to l976 with 3 deaths; 57 reported cases of typhus (type not indicated)

SOURCES/SPECIMENS: Naturally or experimentally infected lice and their feces; flying squirrels may also be a direct source of infection

PRIMARY HAZARDS: Accidental parenteral inoculation and exposure to infectious aerosols

SPECIAL HAZARDS: None

SECTION VII - RECOMMENDED PRECAUTIONS

CONTAINMENT REQUIREMENTS: Biosafety level 2 practices and containment for non-propagative activities (serological procedures, smears); biosafety level 3 for all manipulations of infectious materials, including animal necropsy, and the inoculation, incubation and harvesting of embryonated eggs or tissue cultures; arthropods and flying squirrels should be handled using biosafety level 3 practices and facilities

PROTECTIVE CLOTHING: Gloves and gown (tight wrists and ties in back) when working with agent

OTHER PRECAUTIONS: None

SECTION VIII - HANDLING INFORMATION

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

DISPOSAL: Decontaminate before disposal; steam sterilization, incineration

STORAGE: In sealed containers that are appropriately identified

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

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