Ticks were once so rare they were virtually non-existent in the fields and woods around Petrolia, older residents say.

Now, even a short walk in tall grass can leave you and your pets covered in the crawly bloodsuckers.

Andrew Peregrine, a pathobiology professor at the University of Guelph, says the sudden ubiquity of ticks can be blamed on three things: birds, bucks and climate change.

Deer ticks, which get all the attention because they can transmit Lyme disease, were unknown in Canada until the mid-1990s, he says.

A second species, the American dog tick, was probably already here. But little research has been done on dog ticks because they don’t seem to transmit anything dangerous to pets or people, at least in Canada, he says.

“I came here in 1997 and the number of people who had ever seen a deer tick –  ixodes scapularis –  was very, very small. I’m hearing from (veterinarians) all over Ontario about changes … even three years ago there were areas with no ticks, and now you go for a walk and the next day your dog has 20 engorged ticks.”

Public Health Agency of Canada maps show an upswing in human cases of Lyme disease as deer ticks spread north and west from the U.S. eastern seaboard. Lyme, in fact, is a place in Connecticut that gave the disease its name.

One source of the onslaught is migrating birds, Peregrine said. Deer ticks dropping off birds have already established breeding populations along the north shore of lakes Erie and Ontario.

White-tailed deer is another. They are the tick’s primary food source and their numbers are soaring.

“Climate change seems to be another strong driver, and it’s just going to get worse,” said Peregrine, who suspects warmer winters are also behind the dog tick explosion.

So far, Lambton has dodged a full-out infestation of the more dangerous deer ticks.

Residents turned in 184 ticks they found crawling on themselves last year – the highest number in years – but just five of them were deer ticks, said Lori Lucas, supervisor of health protection.

That’s almost certainly going to change.

“They are moving northwest, towards us, quite dramatically,” Peregrine said,

If that isn’t depressing enough a third species is also headed our way. The lone star tick has in just two decades spread from its Texas home north to Maine and New York State.

“I think you’re going to see it here within the next five years,” Peregrine predicted.

Lucas said Sarnia-Lambton had two “probable” but no confirmed human cases last year of Lyme, which is a potentially debilitating disease.

“Our messaging is always is to stick to the trails and avoid direct contact where you can. But we know that’s not always possible, which is why the buddy system and tick checks are so important.”

Tick tips:

* If walking in tall grass, tuck your shirt into pants and pants into socks. Light colours make ticks easier to spot.

* Apply insect repellent containing DEET to clothing or skin.

* Use a tick and flea collars on pets and check them over periodically.

* After an outing, shower and wash your clothes.

* Do a tick check on yourself, family and pets. Pay attention to scalp, groin and armpits.

* If you find an attached tick, grasp its head with tweezers as close to the skin as possible and pull straight out using steady pressure. Do not twist, squeeze or burn the tick, because that increases risk of infection.

For more, call Community Health Services at 519-383-8331, toll free 1-800-667-1839 or visit www.lambtonhealth.on.ca.

Source: Lambton Public Health

 – By George Mathewson