Environment and Climate Change Canada is predicting warmer than normal temperatures this summer. This prediction might be especially good news for the country’s tick population. Earlier this year, above-normal snowpack in parts of the country protected ticks from the cold, and spring started late. With warmer summer temperatures, tick activity is likely to be robust and to last well into fall.

Most clinicians are quite familiar with identifying and managing the telltale symptoms of Lyme borreliosis, which is caused by black-legged tick bites. But other tick types and pathogens have started to emerge in Canada, underscoring the need for increased clinical vigilance and patient education.

“The black-legged tick is our main culprit here in Canada; it’s the dirty needle of Canadian ticks and carries the vast majority of pathogens,” said Justin Wood, research scientist at the University of Guelph’s G. Magnotta Lyme Disease Research Laboratory in Ontario. Wood also is the founder and CEO of Geneticks Canada, a private lab providing tick testing services. “But several pathogens are emerging and becoming more abundant.”

“We have the lone star tick (Amblyomma americanum) coming into Canada now. Before, these ticks were adventitious, meaning they were coming in on the back of a migratory bird or traveling animal,” said Wood.

“In the last couple of years, we’ve started seeing a lot more in a lot of different life stages like nymphs and adults. What that tells me is that we likely have reproducing populations,” Wood told Medscape News Canada.

Crossing Borders

The lone star tick first obtained notoriety in the United States for its association with alpha-gal syndrome, a severe allergic reaction to red meat, meat products, and dairy. Some patients also develop a rash within 7 days after being bitten that mimics the erythema migrans rash seen with Lyme disease. Other symptoms include fatigue, fever, headache, and joint pain.

Several other tick species will soon be more pervasive in Canada, said Wood. They include the Asian longhorned tick (Haemaphysalis longicornis), which can cause severe fever with thrombocytopenia syndrome, babesiosis, and anaplasmosis. These ticks are the size of a sesame seed and are easily missed by patients looking for attached ticks or bites after being outdoors.

Not every tick bite causes symptoms. Still, nonspecific fevers, muscle aches, and headaches might be dismissed as a virus or summer flu instead of an early sign of Lyme disease, noted Evan Wilson, MD, assistant professor of medicine and program director of the Infectious Diseases Residency Training Program at Queen’s University in Kingston, Ontario.

“What is new and has been emerging in our area is a tickborne illness called anaplasmosis (also caused by the black-legged tick), which can present differently,” said Wilson, “but is treated with antibiotics, similar to Lyme disease.”

Anaplasmosis lacks the telltale, erythema migrans rash of Lyme disease. But symptoms might include high fever and chills, severe headache, muscle pain, fatigue, nausea, vomiting, diarrhea, or loss of appetite.

An Ounce of Prevention

Ticks live in grassy, brushy, or wooded areas. Most patients are aware of the risk of ticks but may not have a routine when they’re outdoors, especially those living or visiting Canada’s east coast. Nova Scotia has the highest incidence of Lyme disease in the country, according to Wood.

For clinicians, patient education is key, explained Wilson, noting the potential for reinfection, which makes diagnosis more challenging.

Clinicians should be aware if someone’s reinfected, he explained. “Testing becomes less useful because it relies on antibody production. If the antibodies remain positive [after the first bite], then you can’t really distinguish a new infection from a previous one. In these cases, you need an objective clinical assessment based on signs and symptoms.”

Findings from a recently published study also suggest that incorporating woodchips — treated or untreated with deltamethrin — into the landscape and along trails can reduce tick populations by as much as 48%-99%.

Additionally, clinicians and patients can bag and send any ticks found on their bodies or clothing to Geneticks Canada for rapid identification so that proper treatment can be initiated early.

Although hot temperatures are a harbinger of increased tick activity, high heat from the dryer can eliminate any ticks that travel into the home on clothing, noted Wood and Wilson.

Patients can be assured that “their infectious disease colleagues are just a phone call away if there’s something that’s not making sense,” said Wilson.

Wilson reported having no relevant financial relationships. Wood is founder and CEO of Geneticks.

Liz Scherer is an independent health/medical journalist who frequently reports on Canadian and global health news. She has reported extensively on emerging infectious diseases.