Rabies, also known as “hydrophobia” is a term that frightens many people. Rabies is a fatal disease that affects all mammals including human beings. It is caused by a virus that attacks the central nervous system causing inflammation of the brain.
The virus lives in the saliva of infected animals. The disease is most often transmitted through the bite of a rabid animal. Inhalation of rabies virus has been known to occur, but only in very special circumstances (such as inhalation in confined areas).
The incubation period, the time between exposure to the disease and the onset of symptoms, varies from a few days to several months. The rabid animal may appear healthy while incubating the rabies virus for several months before contracting clinical symptoms and spreading the virus.
Once symptoms begin, there is no treatment for rabies, and is almost always fatal. An animal that has contracted rabies will have flu-like symptoms, severe headache, and fever. As the disease progresses the animal becomes confused and hallucinates, the brain does not function properly. Many times the animals jaw will drop, this causes them to drool or foam at the mouth. Foxes and raccoons may be out during the daylight, they will not behave normally.
There are two forms of rabies illness displayed in animals. One form is called furious form rabies, animals with this type of rabies may exhibit early symptoms such as restlessness, agitation and increased aggressiveness. This is followed by depression, paralysis and eventually death. The other form of rabies is called dumb form rabies. These animals are lethargic, depressed, partially paralyzed, may appear unusually tame, they will eventually die. You cannot diagnose an animal with rabies by simply observing the animal and there is no test performed on a live animal that can detect the presence of the rabies virus. In order to test for the presence of rabies brain tissue must be sampled.
The disease can be effectively prevented in humans and many domestic animal species, but abundant and widely distributed reservoirs among wild mammals complicate rabies control. There are many different variants of the rabies virus (skunk-strain, fox-strain, raccoon-strain, bat-strain etc…). Each strain may infect any species of mammal. It is extremely important for people to stay away from wild animals such as bats, foxes, raccoons and skunks. It is also very important to make sure that all pets are vaccinated.
Most of the recent human rabies cases in the United States have been caused by bats.
Since the late 70s, 75% of human rabies cases in the United States have been caused by the bat strain of rabies. Bats have very small teeth, therefore, a bite from a bat may not be detected.
Raccoon strain rabies is a strain of rabies carried mainly by raccoons. Raccoon strain rabies is still rabies. It is spread to other wildlife species, domestic animals, pets and humans through the saliva of an infected animal in the same way as other strains of rabies. The only difference is that it is spread primarily by raccoons.
Raccoon rabies was virtually unknown prior to the 1950s. Florida experienced the first case of raccoon rabies. The disease then spread slowly during the next three decades into Georgia, Alabama, and South Carolina. In 1978 Virginia experienced an outbreak of raccoon strain rabies due to the translocation of raccoons from Georgia and Florida. The first cases appeared in West Virginia and Virginia in the late 1970s. Since then, raccoon rabies in the area expanded to form the most intensive rabies outbreak in the U.S.
The strain now occurs in all the eastern coastal states, as well as Alabama, Pennsylvania, Vermont, West Virginia, Ohio, Maine and even southern Ontario.
Raccoon strain rabies was first documented in Tennessee in June, 2003. Four positive cases were discovered in raccoons in Carter County and one positive case was found in a feral cat in Johnson County. A second occurrence of raccoon strain rabies was discovered in January, 2004. Seven raccoons tested positive for raccoon strain rabies in Hamilton County.
The United States Department of Agriculture, Animal and Plant Health Service, Wildlife Services launched an oral rabies vaccination program in 2002. The goal of the program is to stop the westward spread of the raccoon strain rabies. Oral rabies vaccine has been distributed by aircraft in East Tennessee. Following distribution of the oral vaccine, active rabies surveillance has been conducted in the baiting zone. The following is a list of counties in the baiting/surveillance zone: Anderson, Bledsoe, Blount, Bradley, Campbell, Carter, Claiborne, Cocke, Cumberland, Franklin, Grainger, Greene, Grundy, Hamblen, Hamilton, Hancock, Hawkins, Jefferson, Johnson, Knox, Loudon, Marion, McMinn, Meigs, Monroe, Morgan, Polk, Rhea, Roane, Scott, Sequatchie, Sevier, Sullivan, Unicoi, Union, and Washington Counties.
Raccoons and skunks may incubate rabies for long periods (many months) without becoming ill. They may shed the virus in saliva two weeks prior to showing symptoms. Within the baiting/surveillance zone (see figure 1), capturing an animal appearing normal and releasing it in another area later is extremely hazardous. An animal that appears healthy may later come down with clinical rabies. In order to efficiently protect the public and monitor the spread of rabies in wild populations, the translocation of all rabies vector species inside the oral vaccination baiting/surveillance zone has been terminated.
The Tennessee Wildlife Resources Agency is currently precluded by state law from undertaking any direct rabies control. The Tennessee Department of Health is responsible for the investigation of any potential human rabies exposure.