By Ruby Pratka
Local Journalism Initiative
Quebec’s Ministry of Health and Social Services (MSSS) confirmed last week that a case of Rocky Mountain spotted fever (RMSF) – a rare, tick-borne bacterial infection almost unknown in the province until now – had been detected in the Estrie region.
The infection is spread by a bite from the American dog tick (Dermacentor variabilis) – a tick common in the U.S. midwest that is larger than the black-legged tick which causes Lyme disease. According to the U.S. Centers for Disease Control, symptoms of the disease include fever, headache, nausea, stomach pain, muscle pain and the distinctive rash which gives it its name; severe cases can lead to permanent brain damage, hearing loss or death. Early treatment with the antibiotic doxycycline can prevent severe illness. The disease cannot spread from one person to another.
The MSSS “is aware of the situation and is closely monitoring it to obtain further details on the presence of this disease in Quebec,” MSSS media relations co-ordinator Marie-Claude Lacasse told the BCN. “Generally speaking, mosquito- and tick-borne diseases are on the rise. This is an expected consequence of climate change.” She referred requests for further comment to the CIUSSS de l’Estrie–CHUS, which did not respond by press time.
Dr. Alex Carignan, a microbiologist and infectious diseases specialist at the CIUSSS, commented on the case on social media, noting that the patient was responding well to doxycycline treatment. “This infection causes high fevers, a distinctive rash, and can lead to death if not properly managed,” he wrote. “We knew this bacterium would arrive in the coming years, but unfortunately, it has arrived a little earlier than expected.”
Jade Savage is a professor of entomology at Bishop’s University and the creator of the eTick portal, which aggregates crowd-sourced tick data across Canada. She said the recent case of RMSF in Estrie was the first known human case in Quebec in many years, but that cases were not unheard of in Ontario. The eTick portal has recorded 100 to 200 sightings of dog ticks per year in Quebec over the past few years, Savage said.
Savage said RMSF is spread in the same way as Lyme disease, when a tick bites an infected animal – often a rodent – and then bites a human. Ticks need to latch on to their hosts for about 24 hours in order to spread infection. “Dog ticks are big and kind of flashy, and people tend to notice them more readily than the black-legged tick,” Savage said. “They prefer grassy, open areas and can withstand drought better than black-legged ticks.” The two tick species “are very different, but both will readily bite you.”
Savage is a Gen-Xer who grew up on the West Island of Montreal at a time when ticks were not a concern in Quebec. She said the prevalence of different species of ticks – and different, unfamiliar types of tick-borne infections – is an “evolving situation” in light of climate change.
“For a human, a tick bite itself is no big deal, but the concern is the pathogens,” she said. “Different types of pathogens will arise; some will get more common and some less common. Climate change and environmental changes have a quick impact on distribution, and the proportions of different ticks will change over time. There’s absolutely a climate connection, because they’re very adaptable. Most of the species have recently arrived from the U.S. and they just climb their way up.”
Savage advised people who are worried about tick-borne infections or who spend a lot of time outside to cover up well, wear closed-toed shoes, use DEET- or icaridin-based insect repellents and take precautions to keep rodents away from their property. Further tick bite prevention strategies can be found on the eTick portal at ticktool.etick.ca.