Page 117 - Journal of Special Operations Medicine - Fall 2015

An Ongoing Series

Rabies: 2015 Update

Mark W. Burnett, MD

ABSTRACT
Rabies is an almost universally fatal viral disease trans- peripheral nerves, then, eventually, to the central nervous
mitted to humans primarily by bites and scratches from system (CNS), where massive viral replication results in
infected animals, and less commonly through other a progressive encephalomyelitis. The reported time from
routes, including transplantation of infected organs, ex- inoculation to symptomatic infection has varied from
posure to infected neural tissue, and possibly through days to years. Facial and hand bites are thought to most
airborne and aerosolized routes. This disease is endemic quickly result in symptoms, because of the proximity of
to all continents worldwide except Antarctica, and only the CNS and large numbers of nerve synapses for entry.
a few islands elsewhere can be considered “rabies free.”
Special Operations Forces medical providers should be Common initial symptoms are paresthesia and intense
aware of this disease. Prevention and recognition of risk itching at the bite site, fevers, and mood swings. These
are key due to its extreme lethality. are often followed rapidly by hydrophobia and dysauto-
nomia, with death as the most usual outcome.
Keywords: rabies, vaccine

Diagnosis
Human diagnosis can be made by direct fluorescent an-
Introduction
tibody testing on skin biopsy samples taken from the
Rabies is one of the oldest described infectious diseases. nape of the neck, as well as by isolation of the virus
Its name is derived from the Sanskrit rabhas, meaning, in saliva and cerebrospinal fluid (CSF). Serum diagnos-
“to do violence.” The disease was described over 2000 tics can be made by detecting the presence of antibody
years ago and remains a worldwide threat today. Rabies in those who are not vaccinated. The presence of an-
is in the genus Lyssavirus (lyssa from the Greek meaning tibody in the CSF, regardless of previous vaccination
“mad rage”) in the Rhabdoviridae. status, suggests a rabies infection. Gathering laboratory
specimens should be done only after consultation with
Infections are transmitted from animals to humans or, experts at the US Centers for Disease Control and Pre-
more commonly, from animals to other animals, by in- vention (CDC) at 1-404-639-1050.
oculation of infected saliva through bites or scratches
that break the surface of the skin or through skin that is Treatment and Vaccination
otherwise not intact. Rarely, but tragically, humans have
been infected by receiving organ donations from donors Postexposure prophylaxis against rabies infection should
whose rabies infections went unrecognized. Airborne occur as soon as possible after the exposure, beginning
and aerosolized rabies virus has caused infection, as has with thoroughly cleaning the wound site to reduce or
infected neural tissue and saliva that came into contact eliminate any virus that may be present. Soap and water
with exposed mucous membranes. are sufficient. Wounds should not be sutured, if possible.
Tetanus prophylaxis should be considered.
Infection Process and Clinical Presentation
After thorough wound cleansing, Human Rabies Immune
Once infected, replication of the virus may occur locally Globulin (HRIG) (20IU/kg) should be administered only
in muscle, where it can transit from nerve synapse to in those who have not received a complete preexposure

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