The mention of rabies still causes alarm and exaggerated fears among many people, but the truth is that the virus presents much less of a danger to humans now than ever before. Largely thanks to widespread pet vaccinations, aggressive post-exposure treatment policies, and humans' relative resistance to the disease, the numbers of rabies-related human deaths in the United States has steadily declined to an average of only one or two per year. Human fatalities caused by lightning strikes and bad hamburgers far exceed the number of human deaths caused by rabies.
This doesn't mean you shouldn't be concerned about rabies. Sensible precautions should still be taken to protect yourself, your family, and your pets. Preventing exposure to rabies, vaccinating your companion animals, and seeking prompt post-exposure treatment when advised to do so by a physician or local health department are the best ways to guard against this disease.
What is Rabies?
Rabies (Lyssavirus) is an infectious disease that affects the central nervous system in mammals. Saliva provides the primary transmission medium when an animal is in the clinical stage of rabies. The virus is not transmitted through the blood, urine, or feces of an infected animal, nor is it spread airborne through the open environment.
For the rabies virus to get to the salivary glands, it must travel first from the site of entry (usually a bite wound), through the animal's nervous system, and then to the brain. This is what causes most rabid animals to exhibit abnormal behaviors, depending on what part of the brain is infected. Rabies may manifest in a "furious" form, in which an animal may be agitated, bite or snap at both imaginary and real objects, and salivate excessively. The "dumb" form of rabies manifests in animals as creeping paralysis; wild animals may appear "tame" and seem to have no fear of humans.
The rabies virus travels to the salivary glands during the final stage of the disease—this is the time when an animal is most infectious. But the virus cannot penetrate intact skin; people can get rabies only via a bite from a rabid animal or through scratches, abrasions, open wounds, or mucous membranes contaminated with saliva or brain tissue from a rabid animal. And the virus is short-lived when exposed to open air—it isn't viable after saliva dries up. If you are handling a companion animal who has been in a fight with a potentially rabid animal, take precautions such as wearing gloves to prevent any still-fresh saliva from entering an open wound.
Any warm-blooded mammal can carry or contract rabies, but the primary carriers in North America are raccoons, skunks, bats, foxes, and coyotes. Since 1960, rabies has been more frequently reported in wild than in domestic animals in the United States. Wildlife now account for more than 90 percent of all reported rabies cases. Raccoons suffer the most from this fatal disease in the eastern United States, while skunks are the dominant rabies victims in the north and south central states (although skunk rabies also occurs in the East). The occurrence of bat rabies is not limited to any particular geographic area, and cases are scattered widely across the continental United States. Strains of fox rabies occur in western Alaska, parts of Arizona and Texas, and the eastern United States. Coyote rabies has occurred in southern Texas in the past but has been very rare in recent years.
Vaccination programs targeting wildlife have been instituted in many regions over the past 15 years and are helping to reduce the transmission of rabies between wildlife and people. Administered by federal or state wildlife officials, these programs entail the strategic distribution of baits containing oral rabies vaccines for wildlife.
Human Deaths from Rabies
Given all the media attention that rabies regularly receives, it may be somewhat surprising to learn that very few people die from rabies nationwide each year. During the past 10 years, rabies caused a total of 28 human fatalities in the United States, largely because the victims failed to recognize the health risks associated with bite wounds and did not seek medical advice or treatment. Seven of those people died after contracting rabies in a foreign country; five others included an organ donor and organ transplant recipients who tragically succumbed to rabies after the donor was misdiagnosed.
The few human deaths resulting from rabies have been almost entirely due to a domestic bat strain or from a canine strain that victims contracted in a foreign country. Despite the fact that raccoons suffer from rabies more than any other mammal in the United States (about 35 percent of all animal rabies cases), only one human death from the raccoon strain of rabies has ever been recorded in the United States. Most of the bat cases have been of the silver-haired bat strain, which is surprising, since this solitary species is rarely found in or around human dwellings. Only a very small percentage of bats carry rabies—less than one-half of one percent of all bats in North America.
Despite the long odds, the remote possibility of infection exists and should not be taken lightly. If you suspect that a rabid bat has bitten you or if a bat is found in the room where a person is sleeping—scrub any visible bite wound with soap and water right away and seek immediate treatment from a physician or local health department. Immediate medical treatment for any bite wound is always advised. The Centers for Disease Control and Prevention recommend that any bat discovered to have been in a room with a sleeping person be captured and submitted to local or state health authorities for rabies testing. The reason for this is that the bite from a bat can be so insignificant that it could be overlooked by an adult or unreported by a child.
Often the mere sight of a wild animal during the day—such as a fox, raccoon, or skunk—is enough for some people to fear that the animal may have rabies. But wild animals haven't read the textbooks telling them they should be nocturnal. For example, it's actually quite common for foxes to be active during the day. And during the spring and early summer, mother raccoons who are hard pressed to feed their young adequately through their nightly forays often take to foraging during the daylight hours. You many also see orphaned animals active by day. (Learn more about how to recognize if a wild animal is orphaned or injured here.)
Some wild mammals, such as small rodents and rabbits, rarely get rabies. A more common, fatal problem for squirrels is the roundworm brain parasite, which infects the brain and results in clinical signs that look similar to rabies. And no one knows exactly why, but opossums are amazingly resistant to rabies. Hissing, drooling, and swaying are part of the opossum's bluff routine, which is intended to scare away potential predators.