The USDA to continue field assessment of oral rabies vaccine for wildlife in 8 states

Wildlife Services rabies biologists collect a tissue sample from an anesthetized raccoon to assess whether the raccoon has ingested a sufficient amount of the oral rabies vaccine to be protected. (Photo courtesy of Anson Eaglin and the USDA-APHIS)

According to the United States Department of Agriculture (USDA), rabies poses a serious public health concern. Approximately 90% of rabies cases reported in the US come from wildlife, per the CDC.¹ Moreover, rabies is almost always fatal after symptoms begin. Still, this viral disease is 100% preventable.¹ Working towards preventing the spread of wildlife rabies in the United States, the Animal Plant and Health Inspection Service (APHIS) has announced that it will continue field assessment of the oral rabies vaccine bait—ONRAB—in 8 states as part of its collaborative broader rabies control program, titled the National Rabies Management Program, which aims to eventually eliminate terrestrial rabies in the country.^1,2

This year, the assessment will focus on examining ONRAB’s distribution techniques and its effectiveness in raccoons, skunks, and other wildlife species. The ONRAB rabies vaccine, coated with a sweet attractant to act as a bait for wildlife animals, is a blister pack filled with the liquid vaccine. The vaccine entices animals with a sweet coating made from vegetable-based fats, wax, icing sugar, vegetable oil, artificial marshmallow flavor, and dark-green food-grade dye. When animals bite into the bait, the vaccine gets released into their mouth, enabling them to develop immunity from rabies. According to the APHIS, the vaccine has been successfully used in Canada to immunize raccoons, skunks, and foxes against rabies.¹

The ONRAB blister pack. (Photo courtesy of Jordona Kirby, USDA-APHIS-Wildlife Services)

Starting in late July, the lead of the National Rabies Management Program—APHIS’ Wildlife Services (WS)—and its partners, will deploy approximately 3.3 million ONRAB oral rabies vaccine baits via airplanes, helicopters, and vehicles across regions in Maine, New Hampshire, New York, Ohio, Pennsylvania, Vermont, and West Virginia to test the vaccine's impact on targeted wildlife.

Throughout August, the distribution of this oral vaccine bait will cover parts of¹:

• Cattaraugus, Chautauqua, Clinton, Erie, Essex, Genesee, Jefferson, Lewis, Niagara, Oneida, Orleans, Oswego, St. Lawrence, and Wyoming counties in New York
• Addison, Caledonia, Chittenden, Essex, Franklin, Grand Isle, Lamoille, Orange, Orleans and Washington counties in Vermont
• Coos and Grafton counties in New Hampshire
• Franklin and Somerset counties in Maine
• Ashtabula, Belmont, Carroll, Columbiana, Geauga, Harrison, Jefferson, Lake, Mahoning, Portage, and Trumbull counties in Ohio
• Allegheny, Beaver, Crawford, Erie, Greene, Lawrence, Mercer, Washington, and Westmoreland counties in Pennsylvania
• Barbour, Brooke, Greenbrier, Fayette, Hancock, Harrison, Lewis, Marion, Marshall, McDowell, Mercer, Monongalia, Nicholas, Ohio, Pocahontas, Raleigh, Randolph, Summers, Taylor, Upshur, Webster, Wetzel, and Wyoming counties in West Virginia

In October, WS will distribute more than 73,000 ONRAB baits by helicopters and vehicles in southern Tennessee (Bradley, Hamilton, Marion, and Sequatchie counties) to further evaluate the effectiveness of the vaccine with these distribution methods. Approximately 6 to 8 weeks after the bait is distributed, WS personnel will collect samples from raccoons and skunks to determine vaccination rates.

A raccoon holding an oral rabies vaccine bait at a bait station in Florida. (Photo courtesy of Betsy Haley and USDA-APHIS-Wildlife Services)

“Humans and pets cannot get rabies from contact with the bait but are asked to leave the bait undisturbed if they encounter it,” wrote the APHIS in a news release.¹ “If contact with bait occurs, the contact area should be immediately washed with warm water and soap. Each bait carries a toll-free number that people can call if they have additional questions concerning a bait contact.”

According to the APHIS, the 2024 field assessment of ONRAB is a joint initiative involving the APHIS, the CDC, the vaccine producer Artemis Technologies Inc, and various state departments of agriculture, health, and natural resources.¹

Currently, the National Rabies Management Program is using another oral rabies vaccine, RABORAL V-RG, to control the disease in raccoons, coyotes, and foxes. To make the RABORAL V-RG vaccine appealing to animals, the vaccine sachets are either coated with fishmeal or embedded in solid blocks composed of fishmeal and polymer. According to the APHIS, in Florida, raccoon visitation rates to RABORAL V-RG bait stations have been recorded at more than 50%.¹

References

1. USDA continues field assessment of oral rabies vaccine for raccoons and other wildlife. Animal Plant and Health Inspection Service. July 29, 2024. Accessed July 29, 2024. https://www.aphis.usda.gov/news/agency-announcements/usda-continues-field-assessment-oral-rabies-vaccine-raccoons-other#:~:text=This%20year%27s%20field%20assessment%20will,also%20is%20100%20percent%20preventable.
2. National Rabies Management Program overview. Animal Plant and Health Inspection Service. March 11, 2024. Accessed July 29, 2024. https://www.aphis.usda.gov/national-wildlife-programs/rabies