Rabies outbreak traced to U.S. raccoon
More than 300 animals have tested positive for disease in Hamilton since 2015, but numbers have been on the decline
HAMILTON’S ONGOING outbreak of rabies was caused by a patient-zero-like raccoon that hitched a ride on a transport truck or ship to Hamilton from southeastern New York state, a newly released report says.
The multi-agency update — Raccoon Rabies Outbreak in Hamilton, Ontario: A Progress Report — says: “The viruses circulating just across the border in New York state, where raccoon rabies has been endemic since the late 1990s, were phylogenetically very distinct from those responsible for the Hamilton outbreak, supporting the conclusion that this ... represents a long-distance translocation into the area.”
The finding is interesting because other raccoon rabies outbreaks in Canada have been attributed to transborder migration, in that raccoons in the U.S. simply walked north into Canada, infecting raccoons on this side of the border.
“It appears that the disease was introduced after a long-distance translocation of a diseased raccoon, either by water (shipping) or by land (transport trucking),” the report says.
Hamilton Public Health Services is
continuing a public awareness campaign to warn people: “You may be transporting more than you think. Did you know that raccoons are great hitchhikers?”
The hope is to prevent sick raccoon stowaways from Hamilton taking the disease to other communities.
“We hear about it quite often that raccoons end up in transport trucks or ships, because the good folks in these companies report it,” said Connie DeBenedet, manager of vector-borne disease with the city and one of the authors of the report.
The rabies outbreak first surfaced in Hamilton in December 2015 when two bullmastiff dogs — named Lexus and Mr. Satan — got into a scuffle with a sick raccoon in the back of a city Animal Services van.
They were all in cages. But Lexus broke out of his container and attacked the raccoon that also became freed. In the end, both dogs suffered abrasions. Later tests showed the raccoon had rabies and the dogs were put into quarantine to look for signs they had been infected.
This led to the MNR testing all sick and dead raccoons collected by the city and it soon surfaced that many of them had raccoon rabies, a disease that had not been found in Ontario for more than a decade.
A public service campaign was launched by the city, along with the Ministry of Natural Resources, to warn people — and especially pet owners — about raccoon rabies being in the area.
Interestingly, though, the two bullmastiffs turned out to not have contracted raccoon rabies. At the time, a family member said she was not certain whether the dogs had been vaccinated against rabies.
Since 2015 in Hamilton, a total 303 animals have tested positive for the virus, 201 raccoons, 99 skunks, one fox and two stray cats.
“We are seeing the numbers slow down,” said DeBenedet, adding there have been a total of 25 cases so far in 2018 compared to 65 in all of 2017.
“With all the controls the Ministry of Natural Resources have done, we should be seeing the decline,” she said.
Over the past few years, the ministry has spread millions of raccoon vaccine baits in the Hamilton area in an effort to control the spread of the disease.
The report also noted Hamilton’s outbreak is “by far the largest to have occurred in Canada and the first raccoon rabies outbreak documented in a densely populated urban area.”
“Having it in an urban area is a lot more challenging to control with there being a greater risk for our population coming into contact with raccoons and skunks,” DeBenedet said.
The biggest outbreak prior to this in the province began in 1999 in eastern Ontario, with 132 confirmed cases detected over six years. The outbreak was eliminated in 2005 with Ontario being declared free of raccoon rabies in September 2007.
The report noted Hamilton’s outbreak of raccoon rabies is “by far the largest to have occurred in Canada and the first raccoon rabies outbreak in a densely populated area.”