http://ofid.oxfordjournals.org/content/ ... l.pdf+html
Oxford JournalsMedicine & Health Open Forum Infectious Diseases Advance Access10.1093/ofid/ofw269
Geographic Expansion of Lyme disease in Michigan, 2000-2014
Paul M. Lantos, MD, MS GIS1, Jean Tsao, PhD2, Lise E. Nigrovic, MD MPH3, Paul G. Auwaerter, MD MBA4, Vance Fowler, MD MHS5, Felicia Ruffin, RN5, Erik Foster, MS6 and Graham Hickling, phD7
1Divisions of Pediatric Infectious Diseases and General Internal Medicine, Duke University Medical Center, Durham, NC 2Department of Fisheries & Wildlife; Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, MI 3Division of Emergency Medicine, Boston Children’s Hospital, Boston, MA 4 Fisher Center for Environmental Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, MD 5Division of Infectious Diseases, Duke University Medical Center, Durham, NC 6Michigan Department of Health and Human Services 7 Center for Wildlife Health, University of Tennessee Institute of Agriculture, Knoxville, TN
Received December 20, 2016.
<Snip from full text>Abstract
Background. Most Lyme disease cases in the Midwestern United States are reported in Minnesota and Wisconsin. In recent years, however, a widening geographic extent of Lyme disease has been noted with evidence of expansion eastwards into Michigan and neighboring states with historically low incidence rates.
Methods. We collected confirmed and probable cases of Lyme disease from 2000 through 2014 from the Michigan Department of Health and Human Services, entering them in a geographic information system. We performed spatial focal cluster analyses to characterize Lyme disease expansion. We compared the distribution of human cases with recent Ixodes scapularis tick distribution studies.
Results. Lyme disease cases in both the Upper and Lower Peninsulas of Michigan expanded more than five-fold over the study period. While increases were seen throughout the Upper Peninsula, the Lower Peninsula particularly expanded along the Indiana border north along the eastern shore of Lake Michigan. Human cases corresponded to a simultaneous expansion in established I. scapularis tick populations.
Conclusions. The geographic distribution of Lyme disease cases significantly expanded in Michigan between 2000 and 2014, particularly northward along the Lake Michigan shore. If such dynamic trends continue, Michigan can expect a continued increase in Lyme disease cases, as may neighboring areas of Indiana, Ohio, and Ontario, Canada.
Our study is primarily limited by challenges and biases in current Lyme disease surveillance. Physicians report only a small minority of Lyme disease cases, perhaps as little as 10% in some states, and underreporting is most likely not spatially uniform. On the other hand surveillance definitions leave room for false positive misclassification of cases due to a variety of factors. Finally, the ability of a state public health program to address these biases can be strongly influenced by resource allocation and labor.
While we acknowledge these limitations, our approach uses data from more than 1,000 Lyme disease cases over a 15 year period. These data illustrate a trend of northeastward expansion around the shore of Lake Michigan into the Lower Peninsula of Michigan, as well as expansion within the Upper Peninsula. These trends are consistent with both national and local trends demonstrating expansion of the endemic range for Lyme disease in other geographic regions. These trends are also supported by recent expansion in the national distribution of seropositive canines. We do not fully understand the environmental and biological factors that have facilitated spread of this tick and pathogen, nor which factors may ultimately constrain it. In the meantime, further study is needed to optimize both ecological and case surveillance methods in order to best understand these changes in geographic range of this common disease.
Acknowledgements and Financial Disclosures
PML was supported by the National Center for Advancing Translational Sciences of the NIH under award number KL2 TR001115. LEN was supported by a Boston Children’s Hospital Pilot research grant, Harvard Catalyst, and the Bay Area Lyme Foundation. PGA was supported by the Ken and Sherrilyn Fisher Center for Environmental Infectious Diseases and has performed expert medical-legal reviews concerning Lyme disease. VGF and FR were supported by the National Institute for Allergy and Infectious Diseases of the National Institutes of Health under award number K24 AI093969. GH and JT were supported by the Michigan Lyme Disease Association. In addition, GH was supported by cooperative agreement cI00171-01 from the Centers for Disease Control and Prevention.
The three things that I find encouraging are:
1) The interesting and somewhat unusual collaboration between conventional mainstream Lyme researchers and the Michigan Lyme Disease Association and the Bay Area Lyme Foundation. This demonstrates that people on both sides of the controversy can work together. We need more of this.
2) The last sentence in the full text acknowledges that both ecological and case surveillance methods need to be optimized in order to best understand the changes in geographic range. Publicly acknowledging that surveillance methods are sub-optimal would seem to be a step in the right direction.
3) It may seem like a very small thing, but I suspect this is the first time a research article of this type has actually suggested that Lyme is a "common disease". It would definitely seem to be something of a departure from the usual "Hard to catch" side of the false cliché.
Hooray.......at long last! Goodbye to this nonsense from 2001.
http://www.nytimes.com/2001/06/13/us/ly ... finds.html
If I were to express just one criticism of this paper, it is that the authors did not put this acknowledgement somewhere in the abstract where people might be inclined to read it, but instead waited to include it in the very last sentence of the full text.