Abstract
Background
Lyme disease is a multi-system illness with a broad spectrum of clinical manifestations. Infection is caused by the tick-borne bacterium Borrelia burgdorferi. Over the past ten years, the incidence of Lyme disease has increased in Canada due to the spread of its vector, the blacklegged tick, most recently into the eastern region of Ontario. Increase in temperature with climate change and tick range expansion suggest that this trend will continue. Clinicians and the public need to be aware of the increased risk of Lyme disease among patients with outdoor exposures in suitable tick habitat as its region of endemicity expands.
Objectives
To describe the epidemiology of paediatric and adult Lyme disease in Eastern Ontario.
Design/Methods
Detailed local public health data on the incidence of Lyme disease in the general population in a large urban community in Eastern Ontario were analysed from 2009 to 2018.
Results
The incidence rate of locally-diagnosed Lyme disease in the region of study in children 0–18 years of age increased from 0.0/100,000 residents (0 cases) in 2009 to 6.4/100,000 (13 cases) in 2018. Among adults, incidence rates increased from 0.9/100,000 residents (6 cases) to 9.5/100,000 (77 cases). Peak incidence was 15.4/100,000 (31 cases) in children and 20.0/100,000 (159 cases) in adults in 2017 (see Figure). In 2018, 90 cases were diagnosed, median age 50 years, 41% female, 14% in children 0–18 years. The highest paediatric incidence rates were among children 6–10 years of age, and lowest in children 5 and under. Lyme disease diagnoses began in mid-May 2018 and continued until early December with a peak in mid-July.
Conclusion
The incidence of Lyme disease has increased significantly in Eastern Ontario, with highest paediatric incidence noted in children 6–10 years of age. The implications for children with at-risk outdoor exposure in the region are that paediatricians and child health providers must consider Lyme disease as a possible diagnosis for compatible clinical presentations with a history of outdoor exposure to tick habitat in spring through fall months, and a need for ongoing targeted disease prevention strategies.
