Rickettsia rickettsii - Material Safety Data Sheets (MSDS)

 

MATERIAL SAFETY DATA SHEET - INFECTIOUS SUBSTANCES

SECTION I - INFECTIOUS AGENT

NAME: Rickettsia rickettsii

SYNONYM OR CROSS REFERENCE: Rocky Mountain Spotted Fever (RMSF), New World spotted fever, Tick-borne typhus fever, Sao Paulo fever

CHARACTERISTICS: Pleomorphic gram-negative obligate intracellular bacterium 0.3-1.5 µm in size

SECTION II - HEALTH HAZARD

PATHOGENICITY: Sudden onset with moderate to high fever persisting 2 to 3 weeks, malaise, deep muscle pain, severe headache, chills and conjunctival injection; maculopapular rash appears on extremities 3rd day and spreads rapidly; hemorrhages are common; 15-20% case fatality rate in absence of therapy but with treatment death is uncommon; clinical syndrome may be confused with atypical measles, ehrlichiosis, meningococcemia and enteroviral infection

EPIDEMIOLOGY: Occurs through USA during spring, summer and fall; many cases along eastern seaboard and the Rocky Mountain region; adult males infected most frequently in western USA and in East, incidence is higher in children; some infections in Canada, Central and South America

HOST RANGE: Humans, dogs, rodents, various other small animals

INFECTIOUS DOSE: < 10 organisms

MODE OF TRANSMISSION: Ordinarily by bite of an infected tick; several hours of attachment are required before the rickettsiae become reactivated to infect humans; by contamination of skin with crushed tissues or feces of tick

INCUBATION PERIOD: From 3 to 14 days

COMMUNICABILITY: Not directly transmitted from person-to-person; tick remains infectious for life, approximately 18 months

SECTION III - DISSEMINATION

RESERVOIR: Maintained in nature in ticks by transovarian and transstadial passage; transmitted to humans, dogs, various rodents and animals

ZOONOSIS: Yes - bite from ticks from infected animals; contamination of broken skin or mucous membranes with feces or internal contents of crushed tick from infected animal

VECTORS: Ticks - East and South USA - dog tick, Dermancentor variabilis
Northwest USA - wood tick, D.andersoni
Southwest USA - Lone Star tick, Amyblyomma americanum
Latin America - A. cajennense

SECTION IV - VIABILITY

DRUG SUSCEPTIBILITY: Sensitive to tetracyclines and chloramphenicol

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

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

SURVIVAL OUTSIDE HOST: Organism is stable in tick tissues or blood under ambient environmental conditions, surviving up to 1 year; sensitive to drying-feces of infected ticks quickly lose their infectivity on drying

SECTION V - MEDICAL

SURVEILLANCE: Monitor for febrile illness and report symptoms immediately; confirm with IF, IgG does not appear until 7 to 10 days after onset

FIRST AID/TREATMENT: Appropriate antibiotic therapy in the early stages of infection should be initiated on clinical and epidemiologic considerations without waiting for laboratory confirmation of the diagnosis

IMMUNIZATION: None licensed; but may be available as killed experimental product from U.S. CDC

PROPHYLAXIS: Early antibiotic treatment lead to delayed onset of illness or relapse (tetracyclines and chloramphenicol do not kill Rickettsia)

SECTION VI - LABORATORY HAZARDS

LABORATORY-ACQUIRED INFECTIONS: Documented hazard to laboratory personnel; 63 cases reported up to 1976, 11 of which were fatal; one report of 9 cases occurring over a 6-year period in one laboratory (exposure to infectious aerosols)

SOURCES/SPECIMENS: Naturally and experimentally infected mammals, their ectoparasites, and their infected tissues

PRIMARY HAZARDS: Accidental parenteral inoculation and exposure to infectious aerosols (successful aerosol transmission documented in non-human primates)

SPECIAL HAZARDS: None

SECTION VII - RECOMMENDED PRECAUTIONS

CONTAINMENT REQUIREMENTS: Biosafety level 2 practices, containment and facilities for all non-propagative laboratory procedures including serological and fluorescent antibody tests, and staining of impression smears; biosafety level 3 for all other manipulations of known or potentially infectious materials, including necropsy of infected animals and trituration of their tissues, and inoculation, incubation and harvesting of embryonated eggs or tissue culture

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

OTHER PRECAUTIONS: Animal biosafety level 2 practices and facilities are recommended for holding of experimentally infected rodents, however, all necropsy and manipulation of tissue should be conducted at Biosafety level 3

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 all wastes before disposal: incineration, steam sterilization

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