Back to Basics: Rabies
Background
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viral disease caused by lyssaviruses
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transmission occurs when infected animal scratches or bites another animal or human
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globally over ninety percent of transmission is due to dogs; however in the US and other countries with canine control wild animals account for most cases (raccoons, skunks, bats, foxes, etc,)
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bat exposure without a documented bite may require rabies prophylaxis - ex: awakening in a room with a bat
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known dogs or cats should be observed for 10 days
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animals almost never found to be rabid include squirrels, chipmunks, rats, mice, and rabbits
Clinical
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incubation period : 20 - 90 days
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initial symptoms : fever, malaise, headache, anorexia, nausea, pain / paresthesia at bite site
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later symptoms : restlessness, agitation, muscle spasms, hydrophobia, opisthotonos, motor paresis, altered mental status
Diagnosis
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diagnosed clinically - no laboratory test
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confirmatory diagnoses made by postmortem brain tissue studies
Management
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initial assessment should focus on true risk for rabies, notification of public health / animal control, and administration of postexposure prophylaxis
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local wound care VIP
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human rabies immune globulin (HRIG) - administered once after exposure, 20 IU/kg (1/2 locally at exposure site, 1/2 intramuscularly)
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human diploid cell vaccine (HDCV) - administered intramuscularly on days 0, 3, 7, and 14
REFERENCES:
Tintinalli, JE. Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 8th ed. New York, NY: McGraw-Hill Education LLC, 2016.