Rabies

Rabies (hydrophobia) is an acute viral CNS infection of all warm-blooded animals including humans. Usually transmitted by bites of rabid animals; cats/weasels/raccoons/skunks/foxes/bats can also be reservoirs. Virus in saliva enters through the bite wound.

Common Symptoms

Healed bite wound...; somnolence; dyspnea; anorexia; Cheyne-Stokes respiration; restlessness; "three fears" (water sound...); convulsion; nausea; ataxia

Causes and Pathogenesis

Rabies virus (Rhabdoviridae, Lyssavirus) is bullet-shaped, 75-80 × 175-200 nm, with helical nucleocapsid and dense envelope with club-shaped surface projections (honeycomb hexagonal). Negative-sense ssRNA, 11,932 nt, 91% coding for 5 proteins: GP (glycoprotein), M2P (matrix), M1P (capsid matrix), NP (nucleoprotein), LP (polymerase). RNA binds 180 NP molecules as RNP. M2P links envelope/GP/nucleocapsid. GP binds acetylcholine receptors (neurotropism) and induces neutralizing antibodies/cellular immunity. NP is group-specific CFT antigen. Street virus (wild) has long incubation (15-30+ days intracerebral), replicates in salivary glands; fixed virus (after 50+ mouse brain passages) has 3-6 day incubation, nonpathogenic to humans/dogs, no Negri bodies—used for vaccine. UV/formalin/50-70% ethanol/benzalkonium kills; 56°C/30-60 min; survives lyophilized years. Pathogenesis: neurotropic; travels centripetally along nerves (~5 cm/day) to dorsal root ganglia → spinal cord → brainstem/cerebellum; centrifugal spread to salivary glands/taste buds/olfactory epithelium. Cranial nerve nuclei damage → hydrophobia/dysphagia/respiratory spasms; sympathetic overactivity → salivation/sweating; autonomic cardiac damage → sudden death.

Treatment

Drug therapy, supportive therapy

Preventive Measures

Effective treatment is lacking—prevention is key. Vaccinate dogs regularly. Personal: clean pets; wash hands after contact; treat fleas/mites. (1) Reservoir: kill stray dogs; register/vaccinate hunting/police/lab dogs; kill sick dogs/cats immediately; quarantine biting dogs/cats 10 days; brain-examine dead animals (burn/bury, never eat/skin). (2) Wound care: wash immediately with 20% soap water; deep wounds via catheter irrigation; inject anti-rabies serum around wound after negative skin test; do not suture/bandage. (3) Indications: bites by wolves/foxes/dogs/cats that died/escaped; exposure to rabid saliva; head/neck/deep wounds; lab personnel exposed. Hamster kidney cell vaccine: mild bites 2 mL IM days 0/7/14; severe/head/neck bites days 0/3/7/14/30. Equine anti-rabies serum 20 mL adults / 40 IU/kg children; half local, half IM; human rabies IG 20 IU/kg. Boosters at 10/20/90 days after vaccine. Tetanus toxoid/antibiotics as needed.

Department to Visit

It is recommended to visit the Infectious Diseases department; an appointment can be booked on this platform before the visit.

Warm reminder: The above information is for health science reference only and cannot replace professional medical diagnosis. If you have related symptoms, please seek medical attention at a regular hospital promptly.