Most Lyme disease cases are in east

TORONTO — Research for the Canadian Paediatric Surveillance Program found 81 per cent of Lyme disease cases involving kids and youth over a three-year study period were in Nova Scotia and Ontario.

Principal investigator and Halifax-based infectious disease specialist Joanne Langley says the number of incidents in general will increase 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 the median age 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 says 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, Zika virus and eating disorders.

Langley says the study period was not long enough to conclude the rate of increase among kids but she pointed to broader population statistics by the Public Health Agency of Canada that 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.

Langley notes reporting of incidents is also on the rise, “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 says projections expect cases to march north and further west.