Validation of Random Sampling as an Estimation Procedure for Lyme Disease Surveillance in Massachusetts and Minnesota

Abstract

Many disease surveillance programs, including the Massachusetts Department of Public Health and the Minnesota Department of Health, are challenged by marked increases in Lyme disease (LD) reports. The purpose of this study was to retrospectively analyse LD reports from 2005 through 2012 to determine whether key epidemiologic characteristics were statistically indistinguishable when an estimation procedure based on sampling was utilized. Estimates of the number of LD cases were produced by taking random 20% and 50% samples of laboratory-only reports, multiplying by 5 or 2, respectively, and adding the number of provider-reported confirmed cases. Estimated LD case counts were compared to observed, confirmed cases each year. In addition, the proportions of cases that were male, were ≤12 years of age, had erythema migrans (EM), had any late manifestation of LD, had a specific late manifestation of LD (arthritis, cranial neuritis or carditis) or lived in a specific region were compared to the proportions of cases identified using standard surveillance to determine whether estimated proportions were representative of observed proportions. Results indicate that the estimated counts of confirmed LD cases were consistently similar to observed, confirmed LD cases and accurately conveyed temporal trends. Most of the key demographic and disease manifestation characteristics were not significantly different (P < 0.05), although estimates for the 20% random sample demonstrated greater deviation than the 50% random sample. Applying this estimation procedure in endemic states could conserve limited resources by reducing follow-up effort while maintaining the ability to track disease trends.

Surveillance for Lyme Disease — United States, 2008–2015

“…For example, several counties in New York have implemented a system in which 20% of positive laboratory reports are sampled and investigated to determine what proportion can be confirmed; these results are extrapolated to the remaining unsampled laboratory reports to arrive at an estimate of Lyme disease case counts in those counties ( 22 ). Several states are considering adopting similar methodologies to better manage public health surveillance for Lyme disease ( 23 ). In line with historical case-based surveillance systems, case estimates are not reported to CDC through NNDSS, one of several factors that contribute to underreporting of cases nationally.…”

Use of Commercial Claims Data for Evaluating Trends in Lyme Disease Diagnoses, United States, 2010–2018

“…However, as the frequency and geographic distribution of Lyme disease cases have grown, so too has the burden of conducting surveillance. Several high-incidence jurisdictions are pursuing alternative ways to reduce the associated human resource and fiscal burden of conducting Lyme disease surveillance (5)(6)(7). As more jurisdictions adopt alternative sampling, estimation, or triage methods, the comparability of information gained from notifiable disease surveillance decreases (5,7).…”

Characterizing Lyme Disease Surveillance in an Endemic State

“…The challenge in balancing the resource intensiveness of LD surveillance with the valuable knowledge gained from surveillance data further underscores the need to identify alternative approaches to conducting LD surveillance, instead of investigating each and every report. Potential approaches, such as investigating only a systematic sample of reports (Bjork and Brown, ; this issue; Lukacik and White, ; this issue) or querying billing databases for LD diagnoses (Rutz et al., , this issue), are being explored as options to alleviate the burden of LD surveillance on the public health system while retaining the insights gained from this essential public health function.…”