N.L.’s isolation not always a protection against disease

A suspected case of Lyme disease in Newfoundland and Labrador, if confirmed, would be the first one contracted in the province, and highlights how factors like increased travel and a warming climate are reducing the protection from common health concerns that comes with the province’s isolated location.

Four-year-old Kimmy Boland in Brigus is being tested for Lyme disease after her grandmother noticed a telltale bull’s-eye rash on the girl’s arm last month. Previous cases of Lyme diagnosed in the province were contracted from tick bites received elsewhere, but Kimmy has never left the island of Newfoundland, CBC News reported.

That means if she does have Lyme disease, she must have contracted it in the province, which has never before had a confirmed case of Lyme disease transmission, Dr. Hugh Whitney, the province’s chief veterinary officer, tells Yahoo Canada News.

Unlike other Atlantic provinces, such as Nova Scotia and New Brunswick, Newfoundland and Labrador has the distinction of not having a permanent tick population. This “could be the way we stay,” Whitney said. “It’s hard to know.”

One limiting factor for Lyme-carrying tick populations seems to be the existence of white-tailed deer in an area, which are a host for the tick, Whitney said.

The province doesn’t have a white-tailed deer population in Labrador or on the island, which offers some protection against ticks that do make their way here becoming more entrenched, he explained.

But the French islands of Saint-Pierre et Miquelon, just off Newfoundland’s southern coast, do have white-tailed deer. And while there is, to his knowledge, currently no overlap between caribou populations and Lyme-carrying ticks, Whitney said, caribou are in the deer family. So if the populations did overlap the ticks could conceivably use the province’s caribou population as a host.

If the ticks do find a host in the province, isolation won’t be a protection any longer. And the province has experience with how quickly a non-native species can become established. Its iconic moose are actually not native to Newfoundland and Labrador — they were first introduced in 1848, according to the provincial government.

Climate’s role

And sometimes, isolation itself isn’t the protecting factor, Whitney said. For example, Newfoundland and Labrador has no confirmed cases of West Nile transmission, according to the federal government, but that has more to do with its climate than its geographic location.

Surveys of the province’s mosquito population have shown that the key species for West Nile transmission is present, Whitney said. And the virus itself can easily make its way to Newfoundland and Labrador via migrating birds.

The province’s cool climate — in particular its lack of hot and humid summer weather — is likely the difference maker right now when it comes to West Nile, Whitney said.

“Short and cool summers with little bursts of higher temperatures isn’t what the virus needs,” he explained.

But it’s possible that an unusually warm and long summer could give the virus a foothold in the province, he said. And as climate change warms temperatures overall, the likelihood of West Nile being transmitted in Newfoundland and Labrador, and other cooler parts of the country, increases.

Previous research published in the International Journal of Parasitology showed that a similar expansion of the reach of Lyme-carrying ticks could occur as the overall climate warms.

On the other hand, the province’s cold winters could help the rabies that is found cyclically in Labrador’s Arctic foxes making their way south to Newfoundland if foxes cross the ice that forms between the two landmasses during the coldest months of the year, Whitney said.

Two cases of bat rabies have also been found in the province, one in Labrador in 2004 and another in Newfoundland in 1989, he said.

For now, Newfoundland and Labrador remains cautious and watching for signs of Lyme disease in any ticks that are found and reported. The province does test the small number of Lyme-carrying blacklegged (deer) ticks that are submitted, usually after being found on pets and occasionally on humans.

Those ticks generally get in the province either by dropping off migrating songbirds or perhaps arriving on dogs or cats that come in from outside Newfoundland and Labrador, Whitney said.

“Isolation is one factor, but certainly the birds are arriving here,” he said.