What is the treatment for rabies (Rabies virus infection)?

From the Guidelines

Rabies treatment should always include prompt and thorough wound cleansing followed by passive rabies immunization with human rabies immune globulin (HRIG) and vaccination with a cell culture rabies vaccine, as this approach is nearly 100% effective in preventing the disease when administered promptly before symptoms appear. The treatment regimen involves administering HRIG only once, at the beginning of antirabies prophylaxis, to provide immediate, passive, rabies virus neutralizing antibody coverage until the patient responds to the vaccine by actively producing antibodies 1. For persons who have never been vaccinated against rabies, postexposure antirabies vaccination should always include administration of both passive antibody (HRIG) and vaccine (human diploid cell vaccine [HDCV] or purified chick embryo cell vaccine [PCECV]).

Some key points to consider in rabies treatment include:

• Prompt and thorough wound cleansing with soap and water for at least 15 minutes
• Administration of HRIG (20 IU/kg body weight) with as much as possible infiltrated around the wound and the remainder given intramuscularly
• Vaccination with a cell culture rabies vaccine, such as HDCV or PCECV, administered intramuscularly in the deltoid for adults or anterolateral thigh for children
• A regimen of 5 1-mL doses of HDCV or PCECV should be administered intramuscularly to previously unvaccinated persons, with the first dose given as soon as possible after exposure (day 0) and additional doses given on days 3,7,14, and 28 after the first vaccination 1.

It is essential to note that once clinical symptoms of rabies develop, the disease is almost always fatal, which is why immediate treatment is crucial. The vaccine works by stimulating the immune system to produce antibodies against the rabies virus, while the immune globulin provides immediate passive immunity until the vaccine takes effect. Therefore, prompt medical attention and initiation of postexposure prophylaxis are critical in preventing rabies.

From the FDA Drug Label

The only documented cases of rabies from human-to-human transmission have occurred in patients who received corneas transplanted from persons who died of rabies undiagnosed at the time of death. The essential components of rabies post-exposure prophylaxis are wound treatment and, for previously unvaccinated persons, the administration of both human rabies immune globulin (RIG) and vaccine. Local Treatment of Wounds: Immediate and thorough washing of all bite wounds and scratches with soap and water is perhaps the most effective measure for preventing rabies. Active Immunization: Active immunization should be initiated as soon as possible after exposure (within 24 hours). A combination of active and passive immunization (vaccine and immune globulin) is considered the acceptable postexposure prophylaxis except for those persons who have been previously immunized with rabies vaccine and who have documented adequate rabies antibody titer.

Rabies Treatment involves:

• Immediate and thorough washing of all bite wounds and scratches with soap and water
• Active immunization with rabies vaccine as soon as possible after exposure (within 24 hours)
• Passive immunization with Rabies Immune Globulin (Human) in conjunction with rabies vaccine, for previously unvaccinated persons
• Tetanus prophylaxis and measures to control bacterial infection, as indicated Key considerations include:
• Animal species: the type of animal involved in the exposure
• Circumstances of the bite: whether the attack was provoked or unprovoked
• Vaccination status of the animal: whether the animal has been properly immunized
• Presence of rabies in the region: the local epidemiology of rabies 2, 3

From the Research

Rabies Treatment Overview

• Rabies is a fatal zoonotic disease that can be prevented through timely and adequate post-exposure prophylaxis (PEP) 4.
• PEP includes wound washing and antisepsis, a series of intradermal (ID) or intramuscular (IM) rabies vaccinations, and rabies immunoglobulin in WHO category III exposures 4.

Post-Exposure Prophylaxis (PEP)

• The 2010 WHO position on rabies vaccines recommended PEP schedules requiring up to 5 clinic visits over the course of approximately one month 4.
• Abridged schedules with less doses have potential to save costs, increase patient compliance, and thereby improve equitable access to life-saving PEP for at-risk populations 4.
• The 1-week, 2-site ID PEP schedule was found to be most advantageous, as it was safe, immunogenic, supported by clinical outcome data and involved the least direct costs compared to other schedules 4.

Vaccination Schedules

• Pre-exposure prophylaxis consists of 3 doses of an approved rabies vaccine administered either intramuscularly or intradermally on days 0,7, and 21 or 28 with periodic booster doses or titre determination depending on the level of risk of potential exposure to the virus 5.
• Postexposure prophylaxis consists of a multimodal approach to decrease an individual's likelihood of developing clinical rabies after a possible exposure to the virus, including wound cleansing, administration of the rabies vaccine, and administration of human rabies immune globulin 6.

Treatment of Clinical Rabies

• Once clinical manifestations of rabies have developed, treatment options for rabies are limited, and to date, only seven individuals have survived rabies virus infection 6.
• Treatment of clinical rabies consists of medical support in an intensive care unit, using a multifaceted approach that includes supportive care, heavy sedation, analgesics, anticonvulsants, and antivirals 6.

Human Rabies Immune Globulin (HRIG)

• The association of HRIG to the vaccine is recommended for postexposure rabies treatment in cases of severe exposure 7.
• The neutralizing antibody response in the vaccines was found to be identical with both vaccines, ruling out the role of the purification and confirming the excellent immunogenicity of both human diploid cell vaccines and the absence of inhibition of the active immune response by the association of HRIG to HDCV 7.