Rabies & Post-Exposure Prophylaxis
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A child wakes up with a bat in the bedroom but no visible bite marks. The parents want to 'wait and see.' Once you see symptoms, you are planning a funeral.
Core Concept
Rabies virus (genus Lyssavirus) is a neurotropic RNA virus that travels via peripheral nerves to the central nervous system. Once it reaches the brain, the infection is nearly 100% fatal — fewer than 20 people have survived clinical rabies in recorded history. Transmission: bite or scratch from an infected mammal, or contact of saliva with mucous membranes or open wounds. In the US, bats are the most common source of human rabies (many bat bites are not felt — a bat found in a sleeping person's room is considered an exposure). Globally, dogs account for 99% of human rabies deaths. Incubation: typically 1–3 months but ranges from days to over a year, depending on bite location (closer to CNS = shorter incubation), wound severity, and viral load. Clinical rabies progresses through phases: prodromal (fever, malaise, paresthesia or pain at the bite site), acute neurologic (furious form — hydrophobia, aerophobia, agitation, autonomic instability, hypersalivation; or paralytic form — ascending flaccid paralysis), coma, and death. Hydrophobia — violent involuntary pharyngeal spasms triggered by swallowing or even seeing water — is pathognomonic for rabies. Post-exposure prophylaxis (PEP): 1) Immediate thorough wound washing with soap and water for at least 15 minutes. 2) Rabies immune globulin (RIG) — infiltrated as much as anatomically possible into and around the wound, remainder given IM at a site distant from the vaccine. 3) Rabies vaccine series: days 0, 3, 7, and 14 (4 doses for immunocompetent patients). Previously vaccinated individuals receive only 2 vaccine doses (days 0 and 3) and NO RIG. Start PEP immediately for high-risk exposures (bat contact, wild animal bite, unavailable animal) or when the animal is unavailable for testing or observation. For healthy dogs, cats, or ferrets that are available, consult public health — observation or testing may guide whether PEP is needed. Pre-exposure vaccination is recommended for veterinarians, animal handlers, laboratory workers, and travelers to endemic areas. Nursing: wound care is the first intervention, assess vaccination history, initiate PEP immediately when indicated, report to public health for animal investigation, and provide emotional support.
Watch Out For
PEP must start before symptoms — once clinical rabies develops, there is no effective treatment and the outcome is death. This is the single most important distinction. A bat in the bedroom of a sleeping or impaired person is an exposure requiring PEP even without a visible bite — bat bites can be undetectable. For domestic animals (dogs, cats, ferrets) that are healthy and available, public health consultation may guide whether PEP is needed versus observation. RIG is given only once, only at the time of first vaccine dose or within 7 days — it is not repeated. Do not confuse rabies hydrophobia (involuntary pharyngeal spasm from neurological damage) with simple fear of water.
Clinical Pearl
Bat in the bedroom, person was sleeping — that's an exposure. Don't wait for a bite mark you'll never find. Start PEP now.
Test Your Knowledge
3 quick questions — see how well you understood Rabies & Post-Exposure Prophylaxis