To the Editor:
Lyme disease is caused by the bacterium Borrelia burgdorferi, which is transmitted by ticks feeding on infected animals, mainly rodents and birds. Ixodes scapularis, also known as the blacklegged tick, is the most common vector in eastern North America1. Humans can acquire the pathogen when an infected tick feeds on them.
Lyme disease was first recognized in the late 1970s in Connecticut, USA, where an epidemic of oligoarthritis occurred2. In the following years, expanding populations of I. scapularis were identified in northeastern and midwestern American states3. In the early 1990s, only one population of I. scapularis was documented in Canada, located in Ontario1. Since then, 13 established populations of I. scapularis have been progressively identified in Canada3.
Recent evidence suggests that the risk of exposure to Lyme disease is increasing in the province of Quebec1,3,4. Studies indicate that I. scapularis is establishing itself in southern regions, near …
Address correspondence to Dr. J. Bourré-Tessier, Division of Rheumatology, McGill University Health Center, 1650 Cedar Avenue, Montreal, Quebec H3G 1A4. E-mail: josiane.bourre.tessier{at}umontreal.ca