Snapshot A 50-year-old male presents to the ED with dysphagia, hypersalivation, agitation, and generalized muscle twitching. Past medical history revealed patient had right arm pain and paraesthesia one week prior which had failed to resolve. Further questioning revealed the patient had been bitten by a racoon about three months ago while hiking in the woods. He didn't seek medical attention. During physical exam, the patient experienced cardiac arrythymia and hypotension and was resuscitated and mechanically ventilated. CT scan and lumbar puncture were unremarkable. Nuchal biopsy was carried out and samples of the patient's saliva and serum sent for DFA and PCR. Introduction Classification virus RNA negative-stranded rhabdovirus rabies Pathogenesis transmission animal bite animal contact aerosol corneal/organ transplant reservoir U.S. most commonly bats raccoons skunks internationally most commonly dogs molecular biology virus binds to peripheral nicotinic ACh receptors virus travels up axons to DRG via retrograde axoplasmic transport virus enters the spinal cord and rapidly infects the brain Incubation period is weeks to months allows for immunization after exposure Characteristics RNA single-stranded negative-sense linear bullet shaped capsid envelope helical Presentation Symptoms fever and flu-like malaise agitation photophobia hydrophobia brainstem infection leads to painful contractions of pharyngeal muscles when swallowing liquids leads to "foaming at the mouth" seizures disorientation hallucination paralysis coma death secondary to respiratory dysfunction Evaluation Negri bodies collections of virions in the cytoplasm typically occur in the hippocampus and cerebellum pathognomonic Diagnosis clinical Negri bodies on brain biopsy DFA, PCR Differential Herpes simplex encephalitis Seizure disorders Psychosis Tetanus Treatment Prophylaxis following exposure if bitten by a rabid animal (or a bite cannot be ruled out), stimulate immune response while the virus is still in its incubation phase via human rabies immunoglobulin (hRIG) passive immunization 5 doses of killed rabies virus vaccine active immunization Prognosis, Prevention, and Complications Prognosis active rabies is nearly always deadly only 1 confirmed case of recovery Prevention killed rabies vaccine indication animals high-risk individuals Complications cardiac arrest respiratory failure acute renal failure