Rabies is one of the most widely known zoonotic diseases (those which can be transmitted from animals to humans) due to its considerable health implications. Rabies is always present in Nebraska, but with cyclical peaks generally occurring every 5 to 7 years. Nebraska Department of Health and Human Services has had 51 reported cases of rabies in animals by mid-June (2009), making the current summer the highest since 2004 when 64 cases were reported for the year

The Centers for Disease Control and Prevention estimates an annual national cost of over $300 million dollars for rabies prevention and treatment. Although vaccination has proven remarkably efficient in reducing the disease among livestock and companion animals, producers still face exposure risk and economic loss when animals become infected. Human deaths from rabies in the United States are very rare because post-exposure treatment is both effective and safe, however, if untreated, rabies is almost always fatal.

With the development and widespread use of rabies vaccines, occurrence in domestic animals has greatly decreased, and in recent years rabies has been diagnosed more commonly in cats than dogs. Since the 1980s, 90% of rabies cases are in wild animals. All warm-blooded animals may become infected with rabies, but incidence is much higher in certain animals including raccoons, skunks, bats, and foxes which most often spread the disease to domestic animals and people. Rabies is best prevented through routine vaccination of companion animals and high risk livestock. In addition, stray and wild animal control can reduce the rate of rabies transmission because the virus spreads most easily when large numbers of animals are present in an area.

Rabies is caused by a bullet-shaped Rhabdovirus. People or other animals become infected when the virus is transmitted in saliva or tissue from the central nervous system (CNS), particularly the brain. Bites are the most common route of rabies virus transmission. In addition, rabies virus can infect through saliva contact with mucous membrane surfaces of the eyes, mouth, and nose, or through a wound in the skin. Rabies has rarely been transmitted through inhalation of the virus in laboratory settings and within caves with large bat populations. Food-borne exposure is theoretically possible but cooking or pasteurization makes this an unlikely route of exposure. Rabies is not transmitted via blood, urine, or feces.

Once an individual is infected, the virus follows nerves to the central nervous system (brain and spinal column). Following exposure the animal may not show signs of disease for weeks or months since incubation period is dependent on the site bitten and proximity to the brain. Once in the brain, the virus rapidly multiplies and nonspecific signs begin to develop including lethargy, fever and vomiting. The disease progresses rapidly with variable presentation including unprovoked aggression (furious rabies), unusual friendliness or sleepiness with a lack of normal responses (dumb rabies), incoordination and stumbling, abnormal vocalizations, and irregular behavior patterns such as nocturnal animals becoming active during the day. In addition, paralysis of the hind legs or the throat may occur. Involvement of the muscles of the throat produces the most well-known sign - an animal drooling or frothing at the mouth. Veterinarians have been exposed to rabies while examining cattle that appear to be choked. Suspect rabies in animals that appear choked, or with abnormal movement or behavior. Once signs are present, death usually occurs within 7 days.

If you suspect an animal has rabies, contact Nebraska Health and Human Services at 402-471-1374. Testing to confirm a rabid animal must be performed on a dead animal. If you suspect human exposure, consult your physician or the Nebraska Department of Health and Human Services 24-hour hotline at 402-471-2937 for more information. Rabies is a serious health concern; know the signs and ask your veterinarian how to minimize the risk to yourself and the animals under your care. Detailed information on rabies is available from the Centers for Disease Control and Prevention.