In the United States, the decision to give the rabies vaccine to a person who has been bitten by an animal depends on the type and status of the animal.
For people bitten by a pet dog, cat, or ferret: If the animal appears healthy and can be observed for 10 days, the vaccine is not given unless the animal develops symptoms of rabies. If the animal develops any symptom suggesting rabies, people are given the vaccine and rabies immune globulin immediately. Animals that develop symptoms of rabies are put to sleep (euthanized), and their brain is examined for the rabies virus. If the animal is still healthy after 10 days, it did not have rabies at the time of the bite, and vaccine is not needed.
If the status of an animal cannot be determined—for example, because it escaped—public health officials are consulted to determine how likely rabies is to be in that particular area and whether the vaccine should be given. If there are no local public health officials and rabies is possible, the vaccine is given immediately. Very rarely in the United States, if an animal has or appears to have rabies, the vaccine and the immune globulin are given immediately.
For people bitten by skunks, raccoons, foxes, most other carnivores, or bats: Such an animal is considered rabid unless it can be tested and the results are negative. Usually, the vaccine and the immune globulin are given immediately. Waiting to observe wild animals for 10 days is not recommended. When possible, these animals are put to sleep (euthanized), and their brain is examined for the rabies virus as soon as possible. The vaccine is stopped if the animal tests negative for the rabies virus.
Because people may not notice a bat bite, they are given the vaccine if a bite seems possible. For example, if someone awakens and a bat is in the room, the vaccine is given.
For people bitten by livestock, small rodents, large rodents (such as woodchucks and beavers), rabbits, or hares: Each biting incident is considered individually, and public health officials are consulted. People who are bitten by hamsters, guinea pigs, gerbils, squirrels, chipmunks, rats, mice, other small rodents, rabbits, or hares almost never require rabies vaccination.