Information for Veterinarians
Compendium of Animal Rabies Prevention and Control, 2007
The recommendations in this compendium serve as a basis for animal rabies-prevention and -control programs throughout the United States and facilitate standardization of procedures among jurisdictions, thereby contributing to an effective national rabies-control program. This document is reviewed annually and revised as necessary. These recommendations do not supersede state and local laws or requirements. Principles of rabies prevention and control are detailed in Part I; recommendations for parenteral vaccination procedures are presented in Part II, and all animal rabies vaccines licensed by the U.S. Department of Agriculture (USDA) and marketed in the United States are listed in Part III.
Click on the links below for veterinarian frequently asked questions:
- What should I do with an animal that has bitten a person?
- What should I do if my patient was exposed to a rabid or potentially rabid animal and has an up-to-date rabies vaccine?
- What should I do if my patient was exposed to a rabid or potentially rabid animal and DOES NOT have an up-to-date rabies vaccine?
- Should my staff and I be vaccinated against rabies?
- Are veterinarians the only personnel able to give rabies vaccines?
- When can an animal be considered immunized against rabies?
- What rabies vaccination schedule should I follow for my patients?
- What rabies vaccines are licensed in the United States?
- What are the requirements for rabies vaccination if an animal is traveling to another state?
- Can serologic titers be used in lieu of vaccination?
- What samples are needed for rabies testing?
- What tests are performed to diagnose rabies?
- What are the clinic signs of rabies in animals?
- What are the rabies reservoirs in my state?
- What should veterinarians do regarding rabies if responding to manmade or natural disasters?
What should I do with an animal that has bitten a person?
- Dogs, Cats, and Ferrets: Rabies virus might be excreted in the saliva of infected dogs, cats, and ferrets during illness and/or for only a few days before illness or death. A healthy dog, cat, or ferret that bites a person should be confined and observed daily for 10 days. Administration of rabies vaccine to the animal is not recommended during the observation period to avoid confusing signs of rabies with possible side effects of vaccination. Animals in confinement should be evaluated by a veterinarian at the first sign of illness. Any illness in the animal should be reported immediately to the local health department. If signs suggestive of rabies develop, the animal should be euthanized and the head shipped for testing. Any stray or unwanted dog, cat, or ferret that bites a person may be euthanized immediately and the head submitted for rabies examination.
- Other Animals: Other biting animals that might have exposed a person to rabies should be reported immediately to the local health department. Management of animals other than dogs, cats, and ferrets depends on the species, the circumstances of the bite, the epidemiology of rabies in the area, the biting animal's history, current health status, and the animal's potential for exposure to rabies. Previous vaccination of these animals might not preclude the necessity for euthanasia and testing.
What should I do if my patient was exposed to a rabid or potentially rabid animal and has an up-to-date rabies vaccine?
- Dogs, Cats, and Ferrets: Dogs, cats, and ferrets that are currently vaccinated should be revaccinated immediately, kept under the owner's control, and observed for 45 days. Any illness in an isolated or confined animal should be reported immediately to the local health department. If signs suggestive of rabies develop, the animal should be euthanized and the head shipped for testing.
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Livestock: Livestock exposed to a rabid animal and currently vaccinated with a vaccine approved by USDA for that species should be revaccinated immediately and observed for 45 days.
- If an exposed animal is to be slaughtered for consumption, it should be done immediately after exposure. Barrier precautions should be used by persons handling the animal, and all tissues should be cooked thoroughly. Historically, federal guidelines for meat inspectors have required that any animal known to have been exposed to rabies within 8 months be rejected for slaughter. USDA Food and Inspection Service (FSIS) meat inspectors should be notified if such exposures occur in food animals before slaughter.
- Multiple rabid animals in a herd or herbivore-to-herbivore transmission is uncommon; therefore, restricting the rest of the herd if a single animal has been exposed to rabies is usually not necessary.
- Other Animals: Other mammals exposed to a rabid animal should be euthanized immediately. Animals maintained in USDA-licensed research facilities or accredited zoological parks should be evaluated on a case-by-case basis.
What should I do if my patient was exposed to a rabid or potentially rabid animal and DOES NOT have an up-to-date rabies vaccine?
- Dogs, Cats, and Ferrets: Unvaccinated dogs, cats, and ferrets exposed to a rabid animal should be euthanized immediately. If the owner is unwilling to have this done, the animal should be placed in strict isolation for 6 months. Rabies vaccine should be administered to the animal upon entry into isolation or 1 month before release to comply with preexposure vaccination recommendations. No USDA biologics are licensed for postexposure prophylaxis of previously unvaccinated domestic animals, and evidence exists that the use of vaccine alone will not reliably prevent the disease in these animals. Animals with expired vaccinations need to be evaluated on a case-by-case basis.
- Livestock: Unvaccinated livestock should be euthanized immediately. If the animal is not euthanized, it should be kept under close observation for 6 months. Any illness in an animal under observation should be reported immediately to the local health department. If signs suggestive of rabies develop, the animal should be euthanized and the head shipped for testing. Multiple rabid animals in a herd or herbivore-to-herbivore transmission is uncommon; therefore, restricting the rest of the herd if a single animal has been exposed to or infected by rabies is usually not necessary.
- Other Animals: Other mammals exposed to a rabid animal should be euthanized immediately. Animals maintained in USDA-licensed research facilities or accredited zoological parks should be evaluated on a case-by-case basis.
Should my staff and I be vaccinated against rabies?
Preexposure vaccination should be offered to persons in high-risk groups, such as veterinarians, animal handlers, and certain laboratory workers. Pre-exposure vaccination does not eliminate the need for additional therapy after a rabies exposure, but it simplifies therapy by eliminating the need for RIG and decreasing the number of doses of vaccine needed. Pre- exposure prophylaxis might protect persons whose postexposure therapy is delayed and might provide protection to persons at risk for unapparent exposures to rabies. Preexposure vaccination an be given either intramuscularly or intradermally and consists of three injections, one injection per day on days 0, 7, and 21 or 28.
Veterinarians and their staff are classified in either the frequent or infrequent risk categories based on whether they are in rabies enzootic areas. Persons in the rabies enzootic areas are considered to be in the frequent-risk category and should have a serum sample tested for rabies antibody every 2 years; if the titer is less than complete neutralization at a 1:5 serum dilution by the RFFIT, the person also should receive a single booster dose of vaccine. Veterinarians, veterinary students, and animal-control and wildlife officers working in areas with low rabies rates (infrequent exposure group) do not require routine preexposure booster doses of vaccine after completion of primary preexposure vaccination.
Are veterinarians the only personnel able to give rabies vaccines?
Parenteral animal rabies vaccines should be administered only by or under the direct supervision of a veterinarian. Rabies vaccinations also may be administered under the supervision of a veterinarian to animals held in animal-control shelters before release. Any veterinarian signing a rabies certificate must ensure that the person administering vaccine is identified on the certificate and is appropriately trained in vaccine storage, handling, administration, and in the management of adverse events. This practice ensures that a qualified and responsible person can be held accountable for properly vaccinating the animal.
When can an animal be considered immunized against rabies?
Within 28 days after initial vaccination, a peak rabies virus antibody titer is reached, and the animal can be considered immunized. An animal is considered currently vaccinated and immunized if the initial vaccination was administered at least 28 days previously or booster vaccinations have been administered in accordance with recommendations. Because a rapid anamnestic response is expected, an animal is considered currently vaccinated immediately after a booster vaccination.
What rabies vaccination schedule should I follow for my patients?
Vaccination of dogs, ferrets, and livestock can be started at no sooner than three months of age. Some cat vaccines can be given as early as two months of age. Regardless of the age of the animal at initial vaccination, a booster vaccination should be administered 1 year later.
- Dogs, Cats, and Ferrets: All dogs, cats, and ferrets should be vaccinated and revaccinated against rabies according to product label directions. If a previously vaccinated animal is overdue for a booster, it should be revaccinated. Immediately following the booster, the animal is considered currently vaccinated and should be placed on a vaccination schedule according to the labeled duration of the vaccine used.
- Livestock: Consideration should be given to vaccinating livestock that are particularly valuable. Animals that have frequent contact with humans (e.g., in petting zoos, fairs, and other public exhibitions) and horses traveling interstate should be currently vaccinated against rabies.
- Confined Animals:
- Wild: No parenteral rabies vaccines are licensed for use in wild animals or hybrids (i.e., the offspring of wild animals crossbred to domestic animals). The AVMA has recommended that wild animals or hybrids should not be kept as pets (14--17).
- Maintained in Exhibits and in Zoological Parks: Captive mammals that are not completely excluded from all contact with rabies vectors can become infected. Moreover, wild animals might be incubating rabies when initially captured; therefore, wild-caught animals susceptible to rabies should be quarantined for a minimum of 6 months. Employees who work with animals at exhibits and in zoological parks should receive preexposure rabies vaccination. The use of pre- or postexposure rabies vaccinations for handlers who work with animals at such facilities might reduce the need for euthanasia of captive animals that expose handlers. Carnivores and bats should be housed in a manner that precludes direct contact with the public (12)
What rabies vaccines are licensed in the United States?
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What are the requirements for rabies vaccination if an animal is traveling to another state?
Before interstate movement (including commonwealths and territories), dogs, cats, ferrets, and horses should be currently vaccinated against rabies. Animals in transit should be accompanied by a valid 
NASPHV Form 51 (PDF – 53 KB), Rabies Vaccination Certificate. When an interstate health certificate or certificate of veterinary inspection is required, it should contain the same rabies vaccination information as Form 51.
Can serologic titers be used in lieu of vaccination?
Titers do not directly correlate with protection because other immunologic factors also play a role in preventing rabies, and the ability to measure and interpret those other factors are not well developed. Therefore, evidence of circulating rabies virus antibodies should not be used as a substitute for current vaccination in managing rabies exposures or determining the need for booster vaccinations in animals.
What samples are needed for rabies testing?
Rabies testing should be performed in accordance with the established national standardized protocol for rabies testing by a qualified laboratory that has been designated by the local or state health department. Euthanasia should be accomplished in such a way as to maintain the integrity of the brain so that the laboratory can recognize the anatomical parts. Except in the case of very small animals, such as bats, only the head or brain (including brain stem) should be submitted to the laboratory. To facilitate laboratory processing and prevent a delay in testing, any animal or animal specimen being submitted for testing should preferably be stored and shipped under refrigeration and not be frozen. Chemical fixation of tissues should be avoided to prevent substantial testing delays and because it might preclude reliable testing. Questions regarding testing of fixed tissues should be directed to the local rabies laboratory or public health department.
What tests are performed to diagnose rabies?
The direct fluorescent antibody test (dFA) is the test most frequently used to diagnose rabies. This test requires brain tissue from animals suspected of being rabid and can only be performed post-mortem. This test has been thoroughly evaluated for more than 40 years, and is recognized as the most rapid and reliable of all the tests available for routine use. All rabies laboratories in the United States perform this test on animals suspected of having rabies. Other tests for diagnosis and research, such as electron microscopy (EM), histologic examination, immunohistochemistry (IHC), RT-PCR, and isolation in cell culture are useful tools for studying the virus structure, histopathology, molecular typing, and virulence of rabies viruses.
What are the clinic signs of rabies in animals?
Rabies virus causes an acute encephalitis in all warm-blooded hosts and the outcome is almost always fatal. The first symptoms of rabies may be nonspecific and include lethargy, fever, vomiting, and anorexia. Signs progress within days to cerebral dysfunction, cranial nerve dysfunction, ataxia, weakness, paralysis, seizures, difficulty breathing, difficulty swallowing, excessive salivation, abnormal behavior, aggression, and/or self-mutilation.
What are the rabies reservoirs in my state?
Although all species of mammals are susceptible to rabies virus infection, only a few species are important as reservoirs for the disease. In the United States, several distinct rabies virus variants have been identified in terrestrial mammals, including raccoons, skunks, foxes, and coyotes. In addition to these terrestrial reservoirs, several species of insectivorous bats are also reservoirs for rabies.
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What should veterinarians do regarding rabies if responding to manmade or natural disasters?
Animals might be displaced during and after manmade or natural disasters, and they might require emergency sheltering. Animal rabies vaccination and exposure histories often are not available for displaced animals, and disaster response can create situations in which animal caretakers might lack appropriate training and previous vaccination. In such situations, the following rabies-prevention and -control measures should be used to reduce the risk for rabies transmission and the need for human postexposure prophylaxis. Coordinate relief efforts of persons and organizations with the local emergency operations center before deployment; examine each animal for signs of rabies at a triage site; isolate animals exhibiting signs of rabies, pending evaluation by a veterinarian; ensure that all animals have a unique identifier; administer a rabies vaccination to all dogs, cats, and ferrets unless reliable proof of vaccination exists; adopt minimum standards for animal caretakers that include personal protective equipment, previous rabies vaccination, and appropriate training in animal handling; maintain documentation of animal disposition and location (e.g., returned to owner, died or euthanized, adopted, relocated to another shelter, address of new location); provide facilities to confine and observe animals involved in exposures; report human exposures to appropriate public health authorities.
Content Source: National Center for Zoonotic, Vector-Borne, & Enteric Diseases (ZVED)