Kiersten J. Kugeler
, Grace M. Farley, Joseph D. Forrester, and Paul S. Mead
Figure. United States counties with high incidence of Lyme disease by the period when they first met the designated high-incidence criteria, 1993–2012. High-incidence counties were defined as those within a spatial cluster of elevated incidence and those with >2 times the number of reported Lyme disease cases as were expected (based on the population at risk).