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SECTION I - INFECTIOUS AGENT
NAME: Leptospira interrogans
SYNONYM OR CROSS REFERENCE: Leptospirosis, Weil's disease, Canicola fever, Hemorrhagic jaundice, Mud fever,
Swineherd's disease.
CHARACTERISTICS: Spirochete; 170 serovars in 20 serogroups; including icterohaemorrhagiae, canicola, autumnalis,
hebdomadis, australis, pomona.
SECTION II - HEALTH HAZARD
PATHOGENICITY: Fever, headache, chills, severe malaise, vomiting, myalgia and conjunctival suffusion;
occasionally meningitis, rash and uveitis; sometimes jaundice, renal insufficiency, anemia and hemorrhage of the
skin; clinical illness lasts 3 days to few weeks, often biphasic; may have asymptomatic infection; low case fatality
rate but increases with age. Recent outbreaks in Korea, Central America had prominent pulmonary and hemorrhagic
manifestations without jaundice.
EPIDEMIOLOGY: World wide; in urban and rural, developed and primitive areas, except for polar regions; occupational
hazard to rice and sugar cane field workers, farmers, veterinarians, miners, animal husbandpeople, lab workers
handling infected rodents or dogs; outbreaks occur among those exposed to river/lake contaminated by urine of animals.
HOST RANGE: Humans; domestic and wild animals (see Reservoir).
INFECTIOUS DOSE: Not known.
MODE OF TRANSMISSION: Contact of the skin or mucous membranes with contaminated water, soil or vegetation;
direct contact with urine or tissues of infected animals; occasionally through ingestion of contaminated food.
INCUBATION PERIOD: Usually 10 days with a range of 4-19 days.
COMMUNICABILITY: Direct transmission from person to person is rare; may be excreted in urine for usually
I month but has been observed as long as I I months after the acute illness.
SECTION III - DISSEMINATION
RESERVOIR: Farm and pet animals, including cattle, dogs, horses and swine; rats and other rodents act
as the normal carrier host- wild animals, including deer, squirrels, foxes, skunks and even reptiles and amphibians
may be infected; in
Europe, field mice, voles, shrews and hedgehogs are common reservoirs; in carrier animals, an asymptomatic infection
occurs.
ZOONOSIS: Yes - direct and indirect contact with urine, abortion products, and materials contaminated with
urine from infected animals.
VECTORS: None.
SECTION IV - VIABILITY
DRUG SUSCEPTIBILITY: Sensitive in vitro to penicillin, streptomycin, erythromycin and tetracyclines;
doxycycline of value for treatment of human disease when given within 4 days of onset.
SUSCEPTIBILITY TO DISINFECTANTS: Susceptible to 1% sodium hypochlorite (20% commercial bleach), 70% ethanol,
glutaraldehyde, formaldehyde.
PHYSICAL INACTIVATION: Sensitive to moist heat (121o C for at least 15 min.).
SURVIVAL OUTSIDE HOST: Soil contaminated with infected urine - many weeks; in water passed through infected
soil up to 19 days; surface water of lakes up to 10 days depending on salinity; sludge - 5 days; urine of infected
rats stored at room temperature - 5 hours only.
SECTION V - MEDICAL
SURVEILLANCE: Monitor for symptoms of illness; confirm serologically; isolation of leptospires from blood,
CSF or urine.
FIRST AID/TREATMENT: Penicillin or doxycycline treatment within 4 days of onset.
IMMUNIZATION: Vaccines are not commercially available for use in humans, however, immunization of man has
been carried out against occupational exposures to specific serovars in Japan, China, Spain, Israel and Italy.
PROPHYLAXIS: Doxycycline administered orally during periods of high exposure may prevent disease.
SECTION VI - LABORATORY HAZARDS
LABORATORY-ACQUIRED INFECTIONS: Well documented laboratory hazard with 67 reported cases and 10 deaths
up to 1976; an experimentally infected rabbit was identified as a source of infection of L. interrogans
serovar icterohemorrhagiae.
SOURCES/SPECIMENS: Urine, blood, and tissues of infected animals and humans.
PRIMARY HAZARDS: Ingestion, accidental parenteral inoculation, and direct contact of skin or mucous membranes
with cultures or infected tissues or body fluids (especially urine); importance of aerosol exposure not known.
SPECIAL HAZARDS: Direct and indirect contact with fluids and tissues of infected mammals during handling,
care, or necropsy is a source of infection; in animals with chronic kidney infections, the agent is shed in urine
in enormous numbers for long periods of time.
SECTION VII - RECOMMENDED PRECAUTIONS
CONTAINMENT REQUIREMENTS: Biosafety level 2 practices, containment, and facilities for activities involving
the manipulation of known or potentially infectious tissues, body fluids, and the housing of infected animals (for
all serovars).
PROTECTIVE CLOTHING: Laboratory coat; gloves for the handling and necropsy of infected animals and when
there is the likelihood of direct skin contact with infectious materials.
OTHER PRECAUTIONS: None.
SECTION VIII - HANDLING INFORMATION
SPILLS: Allow aerosols to settle; wearing protective clothing, gently cover spill with an absorbent material
(paper towel) and apply 1% sodium hypochlorite (20% commercial bleach), starting at perimeter and working towards
the center; allow sufficient contact time (30 rain) before clean up.
DISPOSAL: Decontaminate before disposal; steam sterilization, incineration, chemical disinfection.
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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