SECTION I - INFECTIOUS AGENT


NAME: Coxiella burnetii


SYNONYM OR CROSS REFERENCE: Q fever, Query fever, Rickettsia.


CHARACTERISTICS: Pleomorphic, gram-negative bacteria.

SECTION II - HEALTH HAZARD

PATHOGENICITY: Acute febrile disease; sudden onset, chills, headache, weakness, malaise, severe sweats; pneumonitis, pericarditis, hepatitis, endocarditis, generalized infections; some inapparent infections; < 1% case fatality rate, self limiting infection.

EPIDEMIOLOGY: Worldwide; incidence is greater than reported; endemic in many areas; explosive epidemics occurred in stockyards, meat packing plants and medical labs using sheep for research; common cases in researchers and visitors.

HOST RANGE: Humans, cattle, sheep, goats.

INFECTIOUS DOSE: 10 organisms by inhalation route.

MODE OF TRANSMISSION: Commonly by airborne dissemination of rickettsia in dust from contaminated premises; airborne organisms may be carried >1/2 mile downwind; by direct contact with infected animals and their birth products (especially sheep), wool from sheep, straw, fertilizer and laundry of exposed persons; raw milk from infected cows has been responsible in some cases.

INCUBATION PERIOD: Depends on size of the infecting dose; usually 2-3 weeks.

COMMUNICABILITY: Direct transmission from person to person is very rare, but may occur in cases of pneumonia.

SECTION III - DISSEMINATION

RESERVOIR: Sheep, cattle, goats, ticks, some wild animals (bandicoots); infected domestic animals are usually asymptomatic but shed massive numbers of organisms at parturition.

ZOONOSIS: Yes - direct contact with infected animals (particularly placenta and placental fluids); inhalation of aerosols from infected animals, bedding, dust, etc.

VECTORS: Ticks - several species.

SECTION IV - VIABILITY

DRUG SUSCEPTIBILITY: Resistant to many antibiotics; tetracycline, chloramphenicol and rifampin may be effective.

SUSCEPTIBILITY TO DISINFECTANTS: Resistance to disinfectants documented; reported susceptibility to sodium hypochlorite, formalin, phenols varies; susceptible to ethanol, glutaraldehyde and gaseous formaldehyde (humidity control is essential).

PHYSICAL INACTIVATION: Resists elevated temperatures, dessication, osmotic shock, UV; inactivated by ether, chloroform, gamma irradiation, 130o C for 60 imin.

SURVIVAL OUTSIDE HOST: Extremely resistant to drying and is stable under a variety of environmental conditions; survives for months and even years in the environment; dried sputum - 30 days; dust - up to 120 days; dried urine of guinea pig - 49 days; feces of tick 586 days- milk - 42 months at 4-6o C; wool 12-16 months at 4-6o C.

SECTION V - MEDICAL

SURVEILLANCE: Monitor for symptoms of infection; confirm serologically.


FIRST AID/TREATMENT: Antibiotic therapy, typically with doxycycline.


IMMUNIZATION: Investigational - Phase I Q fever vaccine (IND) available from USAMRID recommended for those at high risk (those who work with live C. burnetii and sheep) of exposure who have no demonstrated sensitivity to Q fever antigen; Australian vaccine also found to be effective.


PROPHYLAXIS: Antibiotic prophalaxis not shown to be effective.

SECTION VI - LABORATORY HAZARDS

LABORATORY-ACQUIRED INFECTIONS: Second most commonly reported laboratory infection with outbreaks involving 15 or more persons recorded in several institutions; 278 reported cases with 1 death.

SOURCES/SPECIMENS: A broad range of domestic and wild mammals are natural hosts and may serve as potential source of infection to laboratory and animal care personnel; infected arthropods; blood, urine, feces, milk, and tissues of infected animal or human hosts; placenta of infected sheep may contain millions of organisms/gram tissue; milk may contain 100,000 organisms/gram.


PRIMARY HAZARDS: Parenteral inoculation; exposure to infectious aerosols and droplets.


SPECIAL HAZARDS: Exposure to naturally infected and often asymptomatic sheep and to their birth products is a documented hazard to personnel.

SECTION VII - RECOMMENDED PRECAUTIONS

CONTAINMENT REQUIREMENTS: Biosafety level 2 practices and containment for nonpropagative laboratory procedures, including serological examinations and staining of impression smears; biosafety level 3 practices and facilities for activities involving the inoculation, incubation, and harvesting of embryonated eggs or tissue cultures, the necropsy of infected animals and the manipulation of infected tissues.


PROTECTIVE CLOTHING: Laboratory coat; gloves and gown (tight wrists and fastened in back) when working with the agent; masks may also be used.


OTHER PRECAUTIONS: Since infected guinea pigs and other rodents may shed the organisms in urine or feces, experimentally infected rodents should be maintained under Animal Biosafety Level 3.

SECTION VIII - HANDLING INFORMATION

SPILLS: Allow aerosols to settle; wear protective clothing; gently cover spill with paper towels and apply 1% sodium hypochlorite (20% commercial bleach), starting at perimeter and working towards the center; allow sufficient contact time (30-60 min) before clean up.


DISPOSAL: Decontaminate all wastes before disposal; incineration (animal wastes), steam sterilization,


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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