If you notice a steady stream of items falling out of a low-flying plane, don’t worry: It’s not only intentional, it’s something that could prevent you or your pets from contracting rabies.

All week long, Ontario’s Ministry of Natural Resources and Forestry is airdropping bait packets containing the rabies vaccine – about 100,000 of them per day.

They’re doing it over an area stretching along the Highway 401 corridor from Toronto to Kitchener, and southeast as far as Niagara Region.

On Tuesday, they used the Brantford Municipal Airport as their takeoff and landing point.

Kevin Denston’s job is to fly the plane at low altitude along a series of parallel lines, spaced about 750 metres apart.

He’s part of a four-person crew. Two people at the back of the plane load bait packets onto a conveyor belt, which then drops them out of the bottom of the plane to the ground below, while a navigator ensures that the action stops as the plane passes over residential areas and bodies of water.

“It’s actually quite challenging, but enjoyable too,” Denston says.

Like many pilots, Denston has to communicate with other planes to ensure everyone gives each other space. He also has to steer clear of birds – often less of a challenge in higher-flying aircraft – and keep the flight smooth for the two people working at the back of the plane.

Rabies vaccine bait packets

Rabies had been considered eradicated in Ontario for a decade before it resurfaced in late 2015.

A raccoon that found its way into the province from upstate New York tested positive for the disease after getting into a fight with two dogs in the back of an animal control van in Hamilton.

Since then, hundreds of animals have tested positive for the virus, mainly in and around the Hamilton area. A separate strain of rabies has been present in midwestern Ontario, in an area stretching from Wallenstein to Blyth. No human cases have been reported.

While this week’s airdropping isn’t going west of Waterloo Region, a separate campaign is planned for late September stretching as far west as Lake Huron. Additionally, vaccine bait packets are being delivered to forested areas within urban centres by a ground crew.

Once all of that is complete, vaccine bait packets will have been distributed to all locations within 50 kilometres of known rabies cases.

The bait packets are small and vaguely yellowish in colour. They contain the Ministry of Natural Resources and Forestry’s name, a warning that they should not be eaten, and a scent that attracts raccoons, foxes and other animals.

“They have a waxy coating on the outside that smells like vanilla – very sweet-smelling,” says Beverly Stevenson, a ministry science transfer specialist who was part of Tuesday’s airdrop crew.

Dropping the packets at this time of year is particularly important, Stevenson says, because animals born in the spring are now old enough for the immunization to have an effect – and because it’s still too early in the year for wildlife to come across apples, corn or other crops it might find more attractive.

Anyone who finds a packet in their yard is encouraged to wrap their hands in a plastic bag – to keep the packet’s scent intact – and move it to an area where wild animals are more likely to be found.

If a packet is opened and a person is exposed to its contents, officials recommending contacting a doctor as a prescription.

As of July 31, there had been 88 positive rabies tests in Ontario this year. There were 288 positive tests in all of 2016.

In the 1980s, before the first airdropping program began, Ontario was seeing about 1,500 cases of the disease each year.

With reporting by Daryl Morris