Lindsay Armstrong, Canadian Press, published on Wednesday, June 1, 2022, 5:54 AM EDT
The spread of ticks that can transmit Lyme disease is expected to be higher than ever in much of Canada this year, researchers say.
Vet Lloyd, a researcher and director of the Lloyd Tick Lab at Mount Allison University in New Brunswick, says that as the impact of climate change progresses, each tick season is likely to be worse than the last.
“As winters get milder and shorter, ticks survive better and have more time to feed and have a romance with ticks,” Lloyd said in a recent interview on Friday. “Once the female tick finds the male and the food, it can produce about 3,000 eggs. When this starts to happen, (the population) explodes very quickly. “
Nova Scotia has the highest tick-to-human ratio in Canada, Lloyd said, and is second only to Ontario in the number of ticks reported. But insects can be found all over Canada.
People will notice ticks, perhaps on their pets or in their hair, after spending time outside near long grass. They are active from late April to June and then usually rest during the hottest months, Lloyd said. Then the presence of ticks reaches its peak in late September to November.
The little bug is a cause for concern because it spreads Lyme disease, which is harmful to humans and pets. Not all ticks carry the Lyme disease bacterium, but black-legged ticks are more likely to be infected, Lloyd said.
Cases of tick-borne disease in Canada increased by 150 percent between 2020 and 2021, with nearly 2,900 cases reported to the federal government last year. The report notes that the number of Lyme cases may still be low, “as some cases have been undetected or undeclared”.
The most common sign of Lyme disease is an expanding skin rash that usually begins at the site of a tick bite. Other early symptoms include fever, chills, fatigue and headache. If left untreated, the infection can spread to the joints, heart and nervous system.
Justin Wood, chief executive of the Ontario-based tick-testing organization Geneticks, said tick activity continued to rise. “I think everyone will say they see more ticks every year,” Wood said in an interview Tuesday. The Geneticks lab has received more than 400 ticks for testing in the past six weeks, he said. About 1,600 ticks were sent to the laboratory throughout the 2021 tick season.
Lloyd agreed, “This is a bad year for ticks,” she said.
Ticks can breed locally and new tick populations are being introduced to migrating animals, usually by attaching birds, Lloyd said. Ticks also travel and spread locally to mammals such as deer or mice.
The Canadian Veterinary Association says on its website that ticks are expanding in parts of Canada at a speed of about 46 kilometers a year.
A 2019 Ontario University of Ottawa study found that one-third of black-footed ticks in the Ottawa region are carriers of Lyme disease.
Manisha Kulkarni, an associate professor at the University of Ottawa who studies ticks and tick-borne diseases, said in an interview that over the past five to 10 years, researchers have noticed a “large northward expansion” of black-footed ticks in the Ottawa region.
“Ticks are being found in more and more places around the city of Ottawa and closer to areas where people live, so there is a greater chance that people will come into contact with them,” she said on Tuesday. The city of Ottawa reported 180 cases of Lyme disease in 2019, 120 in 2020 and 290 in 2021.
The expansion of ticks to the north is also observed in Quebec. McGill University of Biology associate professor Virginia Million says the tick movement means they can now be found in suburban areas in the south of the province, where they didn’t live even five years ago.
About 10 years ago, there were several places in Quebec where researchers would find established tick populations, she said, all on the south side of the St. Lawrence River.
“Now they have crossed the river and the warmer it gets and the more humidity it has – the conditions are perfect for ticks,” Millien said Monday. “They are almost everywhere in southern Quebec. Including in my backyard. “
In Nova Scotia, ticks can be anywhere, but they are most densely populated in the areas of the south coast and the Annapolis Valley. They are also common in Halifax and the surrounding areas. Researchers collecting and sampling black-legged ticks have found that in Nova Scotia, 30 to 50 percent of them are carriers of Lyme disease.
In order for Lyme disease to be manageable for Canadians who may be infected, Lloyd would like to see enhanced testing for Lyme disease offered in the health care system. Early detection and treatment can dramatically improve the outcome of the disease, she said.
Health officials also advise people to be diligent when spending time outdoors, which means wearing long pants tucked into socks, using insect repellents and carefully checking for ticks when they return home.
This Canadian Press report was first published on June 1, 2022.
—
This story was created with the financial support of the Meta and Canadian Press News Fellowship.
Add Comment