SECTION I - INFECTIOUS AGENT


Name: Rabies virus.

SYNONYM OR CROSS REFERENCE: Rabies, Hydrophobia, Lyssa.

CHARACTERISTICS: Rhabdoviridae, genus Lyssavirus; ssRNA, enveloped with 10 nm spikes, 70 x 175 nm diameter.

SECTION II - HEALTH HAZARD

PATHOGENICITY: Invariably fatal acute viral encephalomyelitis; onset with apprehension, headache, fever, malaise and sensory changes referred to site of preceding animal bite wound; progresses to paresis or paralysis; spasm of muscles of deglutition on attempts to swallow leads to refusal to drink (hydrophobia); delirium and convulsions; duration of 2 to 6 days; death due to respiratory paralysis.

EPIDEMIOLOGY: Worldwide; uncommon in man (primarily a disease of animals); rabies free areas include Australia, New Zealand, Japan, Hawaii, Taiwan, UK, Ireland, Spain, Portugal, mainland Norway, Sweden, some West Indies and Atlantic islands.

HOST RANGE: Humans and animals as follows: urban rabies - dogs and cats; sylvatic or rural rabies - wild carnivores and bats, with sporadic disease among dogs, cats and livestock; in USA and Canada - primarily foxes, skunks and raccoons; in Europe - foxes.

INFECTIOUS DOSE: Unknown.

MODE OF TRANSMISSION: Virus-laden saliva of a rabid animal is introduced by a bite or rarely by a scratch (rarely into a fresh break in skin or through intact mucous membranes); airborne spread demonstrated in caves and in laboratory settings.

INCUBATION PERIOD: Usually 2 to 8 weeks, occasionally as short as 10 days or as long as 1 year or more; depends on the severity of the wound, site of the wound in relation to richness of nerve supply and distance from the brain, amount of virus introduced, protective clothing and other factors.

COMMUNICABILITY:
Transmission from person to person possible (saliva contains virus) but only documented via corneal transplants; dogs and cats infectious 3-5 days before onset of clinical disease; bats shed virus for 2 weeks before clinical symptoms.

SECTION III - DISSEMINATION

RESERVOIR: Many wild and domestic Canidae, including dogs, foxes, coyotes and wolves; also cats, skunks, raccoons and other biting mammals; bats. Rabbits, chipmunks, rats and mice are very rarely, if ever, infected.

ZOONOSIS:
Yes, directly transmitted from rabid animals to humans.

VECTORS: None

SECTION IV - VIABILITY

DRUG SUSCEPTIBILITY: N/A

SUSCEPTIBILITY TO DISINFECTANTS: Susceptible to 1% sodium hypochlorite (20% commercial bleach), 2% glutaraldehyde, 70% ethanol, formaldehyde.

PHYSICAL INACTIVATION: Inactivated on exposure to ultraviolet radiation, by heat (1 hour at 50o C), and by lipid solvents.

SURVIVAL OUTSIDE HOST: Inactivated rapidly in sunlight and does not survive for long periods out of host unless protected in a cool dark area.

SECTION V - MEDICAL

SURVEILLANCE: Monitor for symptoms; confirm serologically.

FIRST AID/TREATMENT: Immediate thorough cleansing and flushing with soap and water of all wounds followed by application of either 70% alcohol, tincture or aqueous solutions of iodine; suturing of wound should be avoided.

IMMUNIZATION: Pre-exposure immunization of individuals at high risk (including laboratory workers, veterinarians and other animal handlers) with Human Diploid Cell Vaccine (HDCV).

PROPHYLAXIS: Administration of rabies immune globulin (RIG) to neutralize virus in wound and vaccination with HDCV as soon as possible after exposure to develop active immunity.

SECTION VI - LABORATORY HAZARDS

LABORATORY-ACQUIRED INFECTIONS: Two documented lab infections from presumed exposure to high-titered infectious aerosols generated in a vaccine production facility and a research facility.

SOURCES/SPECIMENS: All tissues of infected animals with highest titers in CNS, salivary glands and saliva.

PRIMARY HAZARDS: Accidental parenteral inoculation, cuts or sticks with contaminated laboratory equipment bites by infected animals and exposure of mucous membranes or broken skin to infectious droplets of tissue or fluid.

SPECIAL HAZARDS: Naturally or experimentally infected animals, their tissues, and their excretions are a potential source of exposure to laboratory and animal care personnel.

SECTION VII - RECOMMENDED PRECAUTIONS

CONTAINMENT REQUIREMENTS: Biosafety level 2 (fixed virus) and Biosafety level 3 (street virus) practices, containment equipment and facilities are recommended for rabies virus for all activities utilizing known or potentially infectious materials (with vaccination); additional containment and precautions may be indicated for activities with high potential for droplet or aerosol production and for activities involving production of large quantities or high concentrations of infectious materials.

PROTECTIVE CLOTHING: Laboratory coat; gloves, gown with ties in back and tight wrists when working with infected materials.

OTHER PRECAUTIONS: Heavy protective gloves to avoid cuts from instruments or bone fragments; face shield to protect from infectious droplets or tissue fragments; HEPA filter mask may be indicated in some situations.

SECTION VIII - HANDLING INFORMATION

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

DISPOSAL: Decontaminate before disposal; chemical disinfection, steam sterilization, incineration.

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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