What prophylaxis is recommended for a dog bite patient, considering rabies exposure and antibiotic coverage?

Dog Bite Prophylaxis

For dog bite patients, immediately initiate thorough wound washing with soap and water for 15 minutes, assess rabies risk based on local epidemiology and animal observation status, administer full post-exposure prophylaxis (PEP) consisting of human rabies immune globulin (HRIG) at 20 IU/kg plus a 4-dose vaccine series (days 0,3,7,14) if the dog is unavailable for observation or shows signs of rabies, and provide tetanus prophylaxis and antibiotic coverage as indicated for bacterial infection prevention. 1, 2

Immediate Wound Management

• Wash all bite wounds and scratches immediately and thoroughly with soap and water for 15 minutes, as this single intervention markedly reduces rabies risk in animal studies and is perhaps the most effective measure for preventing rabies infection 1, 3
• Follow wound washing with irrigation using a virucidal agent such as povidone-iodine solution if available 1, 2
• Avoid suturing wounds when possible, as this may increase infection risk; decisions regarding primary wound closure should be individualized based on wound size, location, and time since bite 1, 4

Rabies Risk Assessment

High-Risk Scenarios Requiring Immediate PEP

• Dog is unavailable for observation or testing 2
• Dog shows any signs of rabies or dies within 10 days of the bite 2
• Wild terrestrial carnivores (raccoons, skunks, foxes, coyotes) or bats - all bites must be considered rabies exposures requiring immediate PEP 5

Low-Risk Scenarios Allowing Observation

• Healthy-appearing owned dogs can be observed for 10 days - dogs do not shed rabies virus in saliva more than 10 days before showing clinical signs 2, 6
• If the dog remains healthy after 10 days of observation, PEP can be discontinued 2
• Small rodents (rats, mice, squirrels) almost never require rabies PEP, but consult local health department before deciding 5

Rabies Post-Exposure Prophylaxis Protocol

For Previously Unvaccinated Persons

Administer both HRIG and vaccine immediately upon recognition of rabies exposure:

Human Rabies Immune Globulin (HRIG)

• Dose: 20 IU/kg body weight given once on day 0 (the day first vaccine dose is administered) 1, 2, 7
• Infiltrate the full calculated dose around and into all wounds if anatomically feasible; inject any remaining volume intramuscularly at a site distant from vaccine administration 1, 2
• Never administer HRIG in the same syringe or at the same anatomical site as the vaccine 1, 2, 7
• Do not exceed 20 IU/kg - higher doses suppress active antibody production 1, 2
• HRIG can be administered up to and including day 7 after the first vaccine dose if initially missed; beyond day 7, HRIG is not indicated as vaccine-induced antibody response has begun 1, 2

Rabies Vaccine

• Administer 4 doses of HDCV or PCECV, 1.0 mL intramuscularly on days 0,3,7, and 14 1, 2, 7
• Inject in the deltoid muscle for adults and older children; use the anterolateral thigh for young children 1, 2, 7
• Never use the gluteal area - this produces inadequate antibody response and is associated with vaccine failures 1, 2, 7

For Previously Vaccinated Persons

• Administer only 2 doses of vaccine on days 0 and 3 1, 2, 7
• Do NOT give HRIG - it will inhibit the anamnestic antibody response 2, 7
• This applies to anyone who has completed a recommended pre-exposure or post-exposure vaccination series with a cell culture vaccine 1, 2

For Immunocompromised Patients

• Administer 5 doses of vaccine on days 0,3,7,14, and 28 plus HRIG at 20 IU/kg on day 0, even if previously vaccinated 2, 7
• This includes patients on corticosteroids, other immunosuppressive agents, antimalarials, or with HIV, chronic lymphoproliferative leukemia, or other immunosuppressive illnesses 2
• Mandatory serologic testing 1-2 weeks after the final vaccine dose to confirm adequate antibody response 2

Tetanus Prophylaxis

• Assess tetanus immunization status and administer tetanus prophylaxis as indicated 1
• Consider need for tetanus booster based on wound characteristics and vaccination history 1, 4

Antibiotic Prophylaxis

• Administer antibiotic prophylaxis to control bacterial infection as clinically indicated 1, 4
• Dog bites carry significant risk of bacterial infection, particularly when involving deep puncture wounds, hand injuries, or immunocompromised patients 4
• Immediate copious irrigation significantly decreases infection risk 4

Critical Timing Considerations

• Initiate PEP as soon as possible after exposure, ideally within 24 hours, though treatment remains indicated even if weeks or months have elapsed since exposure 2, 7
• There is no absolute cutoff for initiating PEP - rabies incubation periods can exceed one year, and the disease is uniformly fatal once symptoms appear 1, 2
• Delays of a few days for individual vaccine doses are unimportant and do not compromise protection 2

Common Pitfalls to Avoid

• Do not withhold PEP while waiting for animal observation results if the exposure occurred in a rabies-endemic area or the bite was severe; treatment can be discontinued if the animal remains healthy after 10 days 2
• Do not give HRIG to previously vaccinated persons - this is a critical error that suppresses the memory immune response 2, 7
• Do not administer vaccine in the gluteal area - this has been associated with vaccine failures 1, 2, 7
• Do not exceed the recommended HRIG dose of 20 IU/kg - higher doses suppress active antibody production 1, 2

Documentation

• Document the bite injury with photographs and diagrams when appropriate to support medical and legal records 4