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Removing the Mask of Average Treatment Effects in Chronic Lyme Disease Research Using Big Data and Subgroup Analysis

Under-Detection of Lyme Disease in Canada

Department Biology, Mt. Allison University, Sackville, NB E4L 1E2, Canada
Division of General Internal Medicine, University of Calgary, South Health Campus, Calgary, AB T3M 1M4, Canada
Author to whom correspondence should be addressed.
Healthcare 2018, 6(4), 125;
Received: 31 July 2018 / Revised: 30 September 2018 / Accepted: 2 October 2018 / Published: 15 October 2018
Lyme disease arises from infection with pathogenic Borrelia species. In Canada, current case definition for confirmed Lyme disease requires serological confirmation by both a positive first tier ELISA and confirmatory second tier immunoblot (western blot). For surveillance and research initiatives, this requirement is intentionally conservative to exclude false positive results. Consequently, this approach is prone to false negative results that lead to underestimation of the number of people with Lyme disease. The province of New Brunswick (NB), Canada, can be used to quantify under-detection of the disease as three independent data sets are available to generate an estimate of the true human disease prevalence and incidence. First, detailed human disease incidence is available for the US states and counties bordering Canada, which can be compared with Canadian disease incidence. Second, published national serology results and well-described sensitivity and specificity values for these tests are available and deductive reasoning can be used to query for discrepancies. Third, high-density tick and canine surveillance data are available for the province, which can be used to predict expected human Lyme prevalence. Comparison of cross-border disease incidence suggests a minimum of 10.2 to 28-fold under-detection of Lyme disease (3.6% to 9.8% cases detected). Analysis of serological testing predicts the surveillance criteria generate 10.4-fold under-diagnosis (9.6% cases detected) in New Brunswick for 2014 due to serology alone. Calculation of expected human Lyme disease cases based on tick and canine infections in New Brunswick indicates a minimum of 12.1 to 58.2-fold underestimation (1.7% to 8.3% cases detected). All of these considerations apply generally across the country and strongly suggest that public health information is significantly under-detecting and under-reporting human Lyme cases across Canada. Causes of the discrepancies between reported cases and predicted actual cases may include undetected genetic diversity of Borrelia in Canada leading to failed serological detection of infection, failure to consider and initiate serological testing of patients, and failure to report clinically diagnosed acute cases. As these surveillance criteria are used to inform clinical and public health decisions, this under-detection will impact diagnosis and treatment of Canadian Lyme disease patients. View Full-Text
Keywords: Lyme disease; Canada; ticks; C6 ELISA; WCS ELISA; immunoblotting; canine seroprevalence; tick surveillance; Lyme disease prevalence; Lyme disease incidence Lyme disease; Canada; ticks; C6 ELISA; WCS ELISA; immunoblotting; canine seroprevalence; tick surveillance; Lyme disease prevalence; Lyme disease incidence
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MDPI and ACS Style

Lloyd, V.K.; Hawkins, R.G. Under-Detection of Lyme Disease in Canada. Healthcare 2018, 6, 125.

AMA Style

Lloyd VK, Hawkins RG. Under-Detection of Lyme Disease in Canada. Healthcare. 2018; 6(4):125.

Chicago/Turabian Style

Lloyd, Vett K., and Ralph G. Hawkins. 2018. "Under-Detection of Lyme Disease in Canada" Healthcare 6, no. 4: 125.

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