Written by Janet McConaughey
NEW ORLEANS – The US Department of Agriculture has begun dispersing millions of oral rabies vaccine packages from helicopters and planes in 13 states from Maine to Alabama.
Field trial coordinator Gordona Kirby said the main goal is to prevent raccoons from spreading their strain of the deadly virus to countries where it has not been found or has not been widely spread.
Kirby of Wildlife Services, which is part of the USDA’s Animal and Plant Health Inspection Service, said the USDA is also continuing tests of a vaccine approved in Canada to immunize skunks as well as raccoons.
Rabies is spread through the saliva of an infected animal, usually via bites. However, saliva that enters the eyes, nose, or mouth can also infect a person, according to the Centers for Disease Control and Prevention.
Dr. Michael Newlet, the state’s veterinarian, said 13 people in South Carolina considered possible exposure in March because they were bottle-fed or given medication to a sick calf that turned out to have rabies.
Globally, the virus kills 60,000 people a year, most of them bitten by dogs, according to the World Health Organization.
That’s about the same number that gets rabies prevention shots in the United States after being bitten or scratched by an infected or potentially infected animal, according to the CDC.
State and local pet vaccination laws mean that the virus is mostly spread by wildlife in the United States
Kirby said the national rabies control program began in 1997 in Texas, where wolves were spreading the canine type of virus.
She said vaccine drops eliminated this alternative in 2004. Three years later, the CDC declared the nation free of rabies in dogs.
This does not mean that unvaccinated pets are safe. Rabies is among more than 20 different species — seven found in terrestrial mammals and more than 13 in bat species, said rabies control program coordinator Richard Chipman.
A bite from an infected animal of any kind can infect any other mammal. Scratches sometimes do this, because animals lick their paws.
Kirby said a three-year program in Arizona and New Mexico has eradicated the bat strain of rabies in foxes. And Texas, with help from the U.S. Department of Agriculture, dropped 1.1 million baits along the Mexican border in January to prevent coyotes from bringing the dog type back.
Raccoons are the main reservoir for rabies in 18 states along and near the East Coast and skunks in 21 other countries, according to data for 2020, the latest year available.
Bats made up 31% of the approximately 4,500 animals found to have rabies in 2020. But since all of the more than 40 bat species in the United States eat insects and the rest drink nectar or eat fruit, oral vaccinations will be more difficult.
Some scientists have speculated that bats could be pollinated during hibernation, Chipman said, possibly with a fine mist or with a gel that can be transferred from bats to bats. Early research is testing the idea in vampire bats, which live in Mexico and Central and South America and might spread such a vaccine within a colony by brushing each other.
Rabid wildlife is not just a rural problem. A rabid fox was caught on Capitol Hill less than 24 hours after the first report in April. By that time, about half a dozen people had reported bites or gnaws to the US Capitol Police, but others may have gone to other agencies, a Capitol Police spokesperson said via email.
Raccoon rabies campaigns began in August in parts of northern Maine, western Pennsylvania, West Virginia, and southwestern Virginia. 348,000 Raboral V-RG baits were dropped in Maine and 535,000 in the other three states from aircraft in rural areas and from vehicles in urban and suburban areas.
In all, about 3.75 million packages — coated with fishmeal attractant or coated with 1-inch cubes of fishmeal — will be distributed in nine states, ending when 1.1 million drop in Alabama in October.
The vaccine has been found to be safe for more than 60 species of animals including pet dogs and cats. APHIS says that ingesting too many packets of the vaccine may cause an upset stomach for dogs but will not cause any lasting problem.
About 3.5 million doses of the experimental Onrab vaccine are distributed in parts of Pennsylvania, West Virginia and Tennessee — which also get the approved vaccine — as well as four other states.
Onrab comes in blister packs covered with a green coating and flavored with marshmallows. Wildlife Services hopes to have it approved next year despite ongoing delays associated with the pandemic.