What Is Rabies?

Rabies is a zoonotic disease caused by a highly neurotropic RNA virus in the family Rhabdoviridae and genus Lyssavirus. More than a dozen lyssavirus species/genotypes have been identified. Most are human pathogens.1,2,*

*Pathogen: a microorganism that can cause disease.

Closeup of a medical chart marked, diagnosis rabies.

The Deadly Virus

Exposure is usually through a bite wound from a rabid mammal. However, the virus may also be transmitted when saliva or other potentially infectious materials, like neural tissue, contacts fresh, open wounds or mucous membranes. Once saliva enters the body, virions infect peripheral nerves and travel to the spinal cord and brain at a rate of 50 to 100 mm/day. The result is an acute, progressive encephalitis.1-3

Rabies is one of the oldest recorded diseases. It is almost always fatal.2,4

Circular diagram illustrating the process of rabies infection from exposure to hospitalization.

Stages & Signs of Rabies Infection

The clinical spectrum of rabies manifestation is divided into 3 phases4:

  • Prodromal phase
  • Acute neurologic (excitation) phase
  • Coma (terminal) phase
Pages flipping on a calendar.

Incubation Period for Rabies

Depending on the virus involved, the wound size, and the distance of the bite from the central nervous system, incubation may be as short as 5 days—or it may take years. In most cases, rabies incubation in humans ranges from several weeks to months.4

Rabies Prevention

With proper measures, rabies in humans is an entirely preventable disease.4


Preexposure prophylaxis (PrEP) relies on a prophylactic vaccination intended to simplify postexposure prophylaxis (PEP) after exposure to the virus.

PrEP should only be considered for persons at high risk of exposure to rabies, including:

  • People who work with wild animals in research facilities or accredited zoological parks
  • Anyone who frequently comes in contact with potentially rabid bats, raccoons, or other species known to be a risk for having rabies
  • People with high-risk occupations such as veterinarians, animal handlers, rabies researchers, and certain laboratory workers
  • International travelers who are likely to encounter animals in areas where rabies (like dog rabies) is enzootic and immediate access to appropriate medical care may be limited


For the prevention of rabies in humans exposed to rabies virus, the Advisory Committee on Immunization Practices (ACIP) and the World Health Organization (WHO) recommend PEP measures that include:

  • Immediate cleansing of the wound
  • Administration of human rabies immune globulin (HRIG)
  • Vaccination with cell culture rabies vaccines

Rabies Postexposure Prophylaxis Schedule1

Rabies postexposure measures from wound cleansing, to HRIG, vaccination, and notification of health department.

HDCV, human diploid cell vaccine; HRIG, human rabies immune globulin; PCECV, purified chick embryo cell vaccine.
*Remaining volume, if any, should be administered at an anatomical site distant from the vaccine site.
Vaccine exposure to HRIG in syringe may suppress production of active rabies virus antibody.

Discover How Rabies is Transmitted

Important Safety Information for HyperRAB® (rabies immune globulin [human])

Indication and Usage
HYPERRAB® (rabies immune globulin [human]) is indicated for postexposure prophylaxis, along with rabies vaccine, for all persons suspected of exposure to rabies.

Limitations of Use
Persons who have been previously immunized with rabies vaccine and have a confirmed adequate rabies antibody titer should receive only vaccine. For unvaccinated persons, the combination of HYPERRAB and vaccine is recommended for both bite and nonbite exposures regardless of the time interval between exposure and initiation of postexposure prophylaxis. Beyond 7 days (after the first vaccine dose), HYPERRAB is not indicated since an antibody response to vaccine is presumed to have occurred.

Important Safety Information

For infiltration and intramuscular use only.

Severe hypersensitivity reactions may occur with HYPERRAB. Patients with a history of prior systemic allergic reactions to human immunoglobulin preparations are at a greater risk of developing severe hypersensitivity and anaphylactic reactions. Have epinephrine available for treatment of acute allergic symptoms, should they occur.

HYPERRAB is made from human blood and may carry a risk of transmitting infectious agents, eg, viruses, the variant Creutzfeldt-Jakob disease (vCJD) agent, and, theoretically, the Creutzfeldt-Jakob disease (CJD) agent.

The most common adverse reactions in >5% of subjects during clinical trials were injection-site pain, headache, injection-site nodule, abdominal pain, diarrhea, flatulence, nasal congestion, and oropharyngeal pain.

Do not administer repeated doses of HYPERRAB once vaccine treatment has been initiated as this could prevent the full expression of active immunity expected from the rabies vaccine.

Other antibodies in the HYPERRAB preparation may interfere with the response to live vaccines such as measles, mumps, polio, or rubella. Defer immunization with live vaccines for 4 months after HYPERRAB administration.

Please see full Prescribing Information for HYPERRAB.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088


  1. Rupprecht CE, Briggs D, Brown CM, et al; Centers for Disease Control and Prevention (CDC). Use of a reduced (4-dose) vaccine schedule for postexposure prophylaxis to prevent human rabies: recommendations of the Advisory Committee on Immunization Practices. MMWR Recomm Rep. 2010;59(RR-2):1-9.
  2. Feder H, Petersen B, Robertson K, et al. Rabies: still a uniformly fatal disease? Historical occurrence, epidemiological trends, and paradigm shifts. Curr Infect Dis Rep. 2012;14:408–422.
  3. Rao AK, Briggs D, Moore SMM, et al. Use of a modified preexposure prophylaxis vaccination schedule to prevent human rabies: recommendations of the advisory committee on immunization practices—United States, 2022. MMWR Recommendation Rep. 2002. (71)18: 619-627.
  4. Kaur M, Garg R, Singh S, Bhatnagar R. Rabies vaccines: where do we stand, where are we heading? Expert Rev Vaccines. 2015;14(3):369-381.
  5. World Health Organization. Rabies. May 2021, https://www.who.int/news-room/fact-sheets/detail/rabies. Accessed September 15, 2022.