What is the treatment for rabies exposure?

Treatment of Rabies Exposure

For previously unvaccinated individuals exposed to rabies, immediately initiate postexposure prophylaxis consisting of thorough wound cleansing, rabies immune globulin (20 IU/kg), and a 4-dose vaccine series on days 0,3,7, and 14. 1, 2, 3

Immediate Wound Management (Critical First Step)

• Wash all bite wounds and scratches immediately and thoroughly with soap and water for approximately 15 minutes – this single intervention markedly reduces rabies risk in animal studies 1, 2, 3, 4
• Irrigate the wound with a virucidal agent such as povidone-iodine solution if available 1, 2
• Avoid suturing wounds when possible to prevent deeper viral contamination 3
• Administer tetanus prophylaxis and antibiotics as indicated for bacterial infection control 1, 2

Postexposure Prophylaxis for Previously Unvaccinated Persons

Passive Immunization (Rabies Immune Globulin)

• Administer human rabies immune globulin (HRIG) at exactly 20 IU/kg body weight as a single dose on day 0 1, 2, 3
• Infiltrate the full dose of HRIG thoroughly around and into all wounds if anatomically feasible 1, 3
• Inject any remaining HRIG volume intramuscularly at a site distant from vaccine administration 3
• Never administer HRIG in the same syringe or anatomical site as the vaccine 3
• HRIG can be given up to day 7 after the first vaccine dose if not initially available, but is not indicated beyond day 7 1, 3

Active Immunization (Vaccine Series)

• Administer rabies vaccine (HDCV, PCECV, or RVA) as a 4-dose series: days 0,3,7, and 14 1
• For adults, inject intramuscularly in the deltoid area 1, 3
• For children, the anterolateral thigh is also acceptable 1
• Never administer vaccine in the gluteal area – this results in lower neutralizing antibody titers 1
• The 2008 ACIP guidelines updated the regimen from 5 doses to 4 doses (eliminating the day 28 dose), which remains highly effective 1

Postexposure Prophylaxis for Previously Vaccinated Persons

• Administer only 2 doses of vaccine on days 0 and 3 1, 3
• Do not administer HRIG – it may blunt the rapid anamnestic antibody response 1, 3
• This applies to persons who received complete pre-exposure or postexposure vaccination with cell culture vaccines, or those with documented rabies antibody titers 1

Timing and Urgency

• Postexposure prophylaxis is a medical urgency, not a medical emergency – decisions should be made promptly but need not be delayed for consultation 1
• Begin treatment as soon as possible after exposure, ideally the same day 3
• Prophylaxis should be administered regardless of delay, even months after exposure, provided the person shows no clinical signs of rabies 1
• Once clinical rabies symptoms appear, postexposure prophylaxis is ineffective 1

Risk Assessment to Determine Need for Prophylaxis

High-Risk Exposures Requiring Prophylaxis

• Any bite from wild carnivores (skunks, raccoons, foxes, coyotes) or bats should be considered rabid unless proven negative by laboratory testing 2
• All bat exposures warrant prophylaxis unless the bat tests negative – even minimal injury from bat bites necessitates treatment 2, 3
• Consider prophylaxis when a bat is found in a room with a sleeping person, unattended child, mentally disabled person, or intoxicated individual who cannot reliably report contact 3
• Nonbite exposures: contamination of open wounds, abrasions, mucous membranes, or scratches with saliva or neural tissue from a rabid animal 1, 2, 3

Lower-Risk Exposures (Observation Possible)

• Healthy domestic dogs, cats, or ferrets can be confined and observed for 10 days 2, 3
• Do not begin prophylaxis unless the animal develops clinical signs of rabies during observation 2
• If the animal remains healthy for 10 days, prophylaxis is not needed 2
• If the animal becomes ill or dies during observation, immediately begin prophylaxis and submit the animal for testing 2

Exposures Not Requiring Prophylaxis

• Petting a rabid animal or contact with blood, urine, feces, or saliva on intact skin 1, 2, 3
• Bites from rodents (squirrels, hamsters, guinea pigs, gerbils, chipmunks, rats, mice) or rabbits almost never require prophylaxis 2
• Indirect contact or handling of animals without bite or mucous membrane exposure 2

Treatment of Clinical Rabies (Once Symptoms Develop)

• Rabies is not considered curable once clinical symptoms appear – only 6 documented human survivors exist, and 5 had received pre-symptom vaccination 1
• Focus on comfort care and adequate sedation in an appropriate medical facility 1
• Sedation is necessary because patients become extremely agitated with stimuli (loud noises, air currents, water) during the acute neurologic phase 1
• Experimental aggressive therapies (e.g., Milwaukee Protocol) may be considered in specialized tertiary care centers for young, healthy persons at early disease stages, but success rates remain extremely low 1, 5
• Survival, when it occurs, is often associated with significant neurologic deficits requiring lengthy rehabilitation 1

Critical Pitfalls to Avoid

• Failing to infiltrate HRIG directly into and around wounds – this provides crucial immediate passive immunity 1, 3
• Administering vaccine in the gluteal region, which produces inadequate antibody response 1
• Giving HRIG to previously vaccinated persons, which blunts their rapid memory response 1, 3
• Delaying treatment due to uncertainty – when documented or likely exposure occurred, initiate prophylaxis regardless of time elapsed 1
• Inadequate wound cleansing, which is the single most important initial preventive measure 1, 4
• Discontinuing prophylaxis prematurely if the exposing animal escapes or cannot be tested 2
• Failing to consult local or state health departments when uncertainty exists about exposure risk or animal rabies prevalence 1, 2

Efficacy of Postexposure Prophylaxis

• When properly administered, the combination of wound care, HRIG, and vaccine is nearly 100% effective 1, 5, 6
• No failures have been documented in the United States since current cell culture biologics were licensed, despite occasional improper administration 1
• The regimen has been used effectively worldwide on an estimated 10-12 million persons annually 1