Rabies in Animals
 | The rabies virus is a bullet-shaped RNA virus which cannot replicate by itself. It must invade a healthy cell and insert its genetic replication code into the host cell's genetic material. The affinity of rabies virus for specific types of tissue, particularly nervous system tissue and salivary glands, accounts for disease symptoms. |
| The virus is relatively fragile and does not live outside the host for extended periods of time. It is inactivated by disinfectants, soap, drying and sunlight. |
| Rabies is primarily a disease of wild carnivorous mammals
and bats. However, all mammals, including humans, are susceptible to
differing degrees.
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| Virtually all cases of rabies in domestic animals are caused by exposure to wild animals, usually raccoons, skunks or bats. Cats, dogs, cattle and horses are the most frequently affected species. |
| The rabies virus may be transmitted when an animal or human
is exposed to infectious saliva or central nervous system tissue in either
of the following ways:
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| The circumstances of a biting incident or non-bite exposure are important in assessing exposure risk. An unprovoked attack or unusual behavior in an animal indicates higher risk for rabies in that animal. An attack is considered provoked when the victim attempted to handle, feed, intervene in a fight, or restrain a healthy appearing animal, or assist an injured animal in pain. In other words, the animal bit for a reason. Provoked bites are considered lower risk for rabies, but each situation must be evaluated individually. |
Rabies should be suspected in any animal exhibiting behavioral changes. Rabid animals may show a lack of fear, seem disoriented, be paralyzed or partially paralyzed (particularly in the hind quarters), and have difficulty standing or walking normally. They may also be hyper-alert, nervous, aggressive, and salivate excessively, or they may show none of these symptoms. An infectious rabid animal may be healthy in appearance and behavior for a period of time prior to the onset of clinical rabies. Also, these symptoms are not unique to rabies and may be associated with other common diseases of wild and domestic animals.
Management of Animals that Bite People
A healthy dog, cat or ferret that bites a person or is involved in a potential rabies exposure of a person should be quarantined (confined) and observed for 10 days. The quarantine period is based on the length of time the virus may be excreted in the saliva prior to onset of rabies symptoms. If a dog, cat, or ferret shows no clinical signs of rabies during the next 10 days, there is reasonable assurance the animal was not shedding virus at the time of the bite or scratch. Rabies vaccine should not be administered to the animal during the quarantine period.
In lieu of a 10-day quarantine, a stray or unwanted animal that bites a person or domestic animal may be humanely killed and tested. If a stray dog, cat or ferret remains healthy throughout a 10-day quarantine and is then euthanized, there is no reason to test for rabies.
Because of the chance of false negative results, there is no generally acceptable antemortem test for rabies in animals. The DFA test on brain tissue is the standard test for detecting rabies. If the DFA test is negative, rabies virus is considered not to have been in the animal's saliva at the time of the exposure.