Rabies Virus: Taxonomy, Structure, and Pathogenesis

Rabies virus (RABV) is the prototype species of the genus Lyssavirus, family Rhabdoviridae, order Mononegavirales.

Virion Structure

• Bullet-shaped, ~180 × 75 nm.
• Single-stranded, negative-sense RNA genome (~12 kb).
• Nucleocapsid: N protein encapsidating RNA + P (phosphoprotein) + L (polymerase).
• Matrix (M) protein surrounds nucleocapsid.
• Envelope with glycoprotein (G) spikes – sole receptor-binding and neutralizing antigen.

Pathogenesis

Enters via peripheral nerves → retrograde axonal transport to CNS → encephalitis → centrifugal spread to salivary glands → transmission via bite. Incubation: weeks to months (site-dependent).