Rabies Transmission, Pathogenesis, and Post-Exposure Prophylaxis

Transmission

Rabies virus (Lyssavirus) enters via saliva of infected mammal through bite, scratch, or mucous membrane exposure. Bats, raccoons, skunks, foxes, dogs (endemic areas) are reservoirs.

Pathogenesis

1. Virus replicates locally in muscle
2. Enters peripheral nerves → retrograde axonal transport to CNS
3. Encephalitis: neuronal dysfunction, inflammation
4. Centrifugal spread to salivary glands, skin, cornea

Clinical

Incubation: weeks–months (site-dependent). Prodrome: fever, paresthesia at bite site. Neurologic: agitation, hydrophobia, aerophobia, paralysis, coma. Nearly 100% fatal once symptomatic.

Prevention

• Pre-exposure vaccination: High-risk occupations, travelers
• Post-exposure prophylaxis (PEP): Wound cleaning + rabies immune globulin (RIG) + 4-dose vaccine series (Days 0, 3, 7, 14). Start immediately—do not wait for symptoms.

Any potential exposure → urgent medical evaluation for PEP determination.