Volume 21, Number 8—August 2015
Geographic Distribution and Expansion of Human Lyme Disease, United States
|Location, period||No. counties||Relative risk, range†||Average annual incidence, range‡||No. counties added to high-incidence status||No. counties removed from high- incidence status|
*In the first period, 4 counties in the southeastern United States met high-incidence criteria but are not included in the geographic focus–specific data. NA, not applicable.
†Relative risk is observed number of cases over a period divided by expected number of cases for the population at risk (4). For this analysis, high-incidence counties had a relative risk of >2.0.
‡Incidence is reported cases per 100,000 residents per year; population used was average population at risk during a period (US census data for midpoint of each period).
- Page created: May 11, 2016
- Page last updated: May 11, 2016
- Page last reviewed: May 11, 2016
- Centers for Disease Control and Prevention,
National Center for Emerging and Zoonotic Infectious Diseases (NCEZID)
Office of the Director (OD)