Lyme disease in children examined in study

81 per cent of cases were in Ontario and Nova Scotia; number expected to rise as tick populations spread, research shows

TORONTO — Research for the Canadian Pediatric Surveillance Program found 81 per cent of Lyme disease cases involving children and youth over a threeyear study period were in Nova Scotia and Ontario.

Principal investigator and Halifax-based infectious disease specialist Joanne Langley says the number of incidents will rise as tick populations spread further into parts of southern Ontario, Quebec, Nova Scotia, New Brunswick and Manitoba.

The study involved 96 cases among patients younger than 16 between July 2014 and June 2017, with a median age of seven years old. More than half of the cases — 56 — were caught at a later stage when more serious symptoms such as arthritis can set in.

Langley said that’s likely because consultant pediatricians are more likely to see later stages, while acute cases are typically handled by primary care doctors or hospitals.

The study says 25 cases were found during the early stage, which typically includes a circular rash near the tick bite, and 15 cases were found just past that stage as the infection spread to other parts of the body.

The study was part of the surveillance program’s larger look at a host of hot-button issues, including the use of cannabis for medical purposes, the Zika virus and eating disorders.

Langley said the study period was not long enough to conclude the rate of increase among kids, but she said broader population statistics by the Public Health Agency of Canada found significant jumps over the past decade.

“It does seem to be creeping up in frequency. That tells me that we need to be sure that clinicians know how to recognize Lyme disease and that the general public knows how to prevent it where possible,” said Langley, a pediatric professor at Dalhousie University and an infectious disease specialist at IWK Health Centre.

The reporting of incidents is also on the rise, Langley said, “and that’s partly due to better recognition, increased testing and also we think that the disease is spreading over a wider geographic range in Canada, thought to be likely due to changing climate.”

She said cases are projected to march north and further west.

The study says Nova Scotia doctors reported 40 cases, while 37 came from Ontario.

Nine cases were reported from Quebec, with the remaining 10 cases spread among British Columbia, Alberta, Manitoba, New Brunswick and Newfoundland and Labrador.

The study says accurate estimates of the number of Canadian kids affected are not available.

We need to be sure that clinicians know how to recognize Lyme disease.

JOANNE LANGLEY

INFECTIOUS DISEASE SPECIALIST