Wildlife Services: What is Rabies

Background

Rabies is one of the oldest known viral diseases, yet today it remains a significant wildlife-management and public-health challenge. Rabies affects the central nervous system of unvaccinated animals that are exposed to the virus and is invariably fatal. Over the past 30 years, rabies management has grown in complexity in the United States, as wild animals, including skunks, raccoons, foxes, coyotes, and bats, have replaced the domestic dog as the primary reservoir for the disease. The Centers for Disease Control and Prevention reports that wildlife currently account for greater than 90 percent of reported cases of rabies in the United States.

The cost of living with rabies in America is high and growing, exceeding $300 million per year. Although rabies vaccinations have been available for domestic animals for many years, until recently no such preventive measure existed to control rabies in wildlife.

The Rabies Virus

Rabies is a bullet-shaped virus that affects the central nervous system of mammals, including humans. Rabies is passed along through saliva when an infected animal bites an uninfected animal. The virus then migrates through the central nervous system to the brain where it begins replicating. From the brain, the virus then begins to infect other tissues, including the salivary glands, where the virus can then be passed to another animal. As the virus replicates in the brain, the animal’s behavior changes and begins to show signs of rabies such as aggression or staggering. Time between the initial bite and death is variable among species and can range from 3 to 20 weeks. For a complete description of rabies, please visit the Centers for Disease Control and Prevention Web site

The Role of the Wildlife Services (WS) Program WS, a program within the U.S. Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS), helps alleviate or minimize wildlife damage to agricultural, urban, and natural resources. An important part of WS’ mission includes assisting in wildlife disease-management to protect public health and safety. Since 1997, WS has been working cooperatively with local, State, and Federal governments; universities; and other partners to manage rabies in wild carnivores through education, surveillance, and oral rabies vaccination (ORV). A vaccination zone has been established from Maine to Alabama to prevent the westward and northward spread of raccoon rabies.

Geographic features such as large lakes and rivers as well as the Appalachian Mountains act as natural barriers that help define the vaccination zone. In 2005, almost 9 million oral rabies vaccine-laden baits were distributed in 15 Eastern States, targeting raccoon rabies. In addition to working toward eliminating rabies where it already exists, WS also works with States to monitor uninfected areas near the vaccination zones. If a positive case were discovered, a contingency action plan would be implemented. The plan would include WS personnel and cooperators’ conducting enhanced rabies surveillance. WS might also trap raccoons to vaccinate them against the disease andthen return them to the wild. In addition, WS would consider distributing oral rabies baits containing vaccine where the first case or cases originated to create immunity and prevent rabies from spreading.

Additional Information

For more information, please visit the National Rabies Management Program’s Web site or call 1–866–4–USDA–WS to contact your WS State office.