GRAND ISLE, Vt. – Two raccoons caught in live traps here last week acted normal and appeared healthy.

U.S. Department of Agriculture Wildlife Specialist Robert Acabbo tranquilized them, drew blood, vaccinated them for rabies and then put on two ear tags. After they woke up, he released them in the same location where they’d been caught.

The blood will be tested to see if the animals had ingested any of the rabies vaccine that has been spread across northern Vermont, New York, New Hampshire and parts of Maine. One of the goals of the program, which began in 1997, was to try to stop a raccoon strain of rabies from crossing the border into Canada.

For years, rabies was contained well south of the border, but last year – for the first time – rabies was found in Canada along the Richelieu River near St. Jean, Quebec, about 30 miles north of the border.

“Now that we’ve had positives in Franklin County, [the goal] is to build up the population of vaccinated animals, remove any animals that are sick to fight against the rabies spreading further,” Acabbo said.

A similar process is under way in Quebec around the location where the first case was reported last year. Since then, there have been a handful of other cases, said Dennis Slate, the USDA’s national rabies management coordinator, who works out of Concord, N.H.

Since February, Acabbo and other technicians have trapped, vaccinated and released more than 1,000 raccoons along Lake Champlain. In addition, thousands of doses of raccoon bait laced with vaccine has also been spread by hand or dropped from airplanes along a 30-mile-wide swath south of the Canadian border from the Connecticut River valley into upstate New York. There’s another program in eastern Maine.

Now the USDA is working with 17 states and three Canadian provinces to stop the spread of rabies.

“We live in a sea of rabies,” Slate said.

Rabies can infect any mammal, including humans, and when caught by people it is almost always fatal, although human cases are rare.

The rabies strain the USDA and officials from the other states and Canadian provinces are fighting first appeared in Vermont in 1994. It originated in Florida. The disease escaped northward in 1977 when infected raccoons were moved from Florida to West Virginia, apparently by hunters, Slate said.

Raccoon rabies is distinct from a strain of rabies more prevalent in foxes that swept the area a decade ago and has since disappeared.

Slate said raccoon rabies had been moving northward at a rate of about 25 to 30 miles a year until it approached the border. The oral rabies vaccine zone across New York, Vermont and New Hampshire was established in 1997.

It worked for years.

“Had intervention not taken place, based on the spread rates, it should have been way north of there,” Slate said.

Officials don’t know how the rabies made it through the vaccine zone last year.

Rabies doesn’t just spread animal to animal. One of the most common ways infected animals are moved around is when people catch a nuisance raccoon in their garage or elsewhere and then take it somewhere else to be released.

And Acabbo said that he has seen raccoons scramble out of garbage trucks from southern Vermont that were dumped at northern Vermont landfills.

“It happens all the time,” Acabbo said. “It’s not that people are trying to break the law or being negligent about it. They don’t know.”