Tickborne Disease Metadata: Incidence


Tickborne disease data are from the Maine CDC Division of Infectious Disease.  Population data are from the U.S. census for state and county level analyses. Population data for town level analyses are from the Maine CDC’s Office of Data, Research, and Vital Statistics.

Dates Available:

2001 - 2022

Geographic Resolution:

State, County, Town


The Maine EPHT program receives tickborne disease data from the Infectious Disease Epidemiology Program at the Maine CDC.  Tickborne disease cases among Maine residents are analyzed, stratified by geographic resolution, age-group and sex.

The dataset contains the following measures:

1. Crude rate of anaplasmosis per 100,000 population
2. Number of anaplasmosis cases
3. Crude rate of babesiosis per 100,000 population
4. Number of babesiosis cases
5. Crude rate of Lyme disease per 100,000 population
6. Number of Lyme disease cases


This data set supports efforts to improve public health in Maine and contributes to the U.S. CDC’s National Environmental Public Health Tracking (EPHT) Network. A key activity of participants in this network is to track and make available environmental health measures on state and national data portals. Measures derived from the data set described here can be used to compare tickborne disease incidence across the state, between groups of people, over time, and in relation to risk factors, exposures, and health outcomes.

The Maine Tracking Network, a member of the National EPHT Network, connects communities, public health professionals, policy makers, state agencies, and others to the data they need to monitor public health, respond to health concerns, prioritize resources for public health action, and evaluate prevention activities. Maine tracks certain health effects, exposures, and environmental hazards that have known relationships, as well as some health effects and environmental hazards that have suspected relationships. By making health and environmental data available through the Maine Tracking Network, more people have access to data they need to think critically and hypothesize about health outcomes and their relationships to conditions in the environment.

Supplemental Information:

Anaplasmosis, babesiosis and Lyme disease are nationally notifiable conditions in the U.S.  The tickborne disease measures on the EPHT portal enable surveillance functions including the monitoring of trends over time and the identification of high risk groups.

Tickborne disease cases are classified according to the Council of State and Territorial Epidemiologists’ case definitions.  Case definitions have changed over time; anaplasmosis, babesiosis and Lyme disease cases are classified according to the most current case definition at the time of report.

Entity and Attribute Overview:

The dataset includes the following fields: year of disease onset, geographic resolution, sex, and age group, rate and number.

Data Limitations:

  • Surveillance data are reported by place of patient residence, which is not necessarily the place where the tickborne disease was acquired.
  • The Lyme disease case definition was established in 1991 by the federal CDC, and modified in 1996, 2008, 2011 and 2022. Changes may impact surveillance and must be considered when attempting to interpret trends.
  • The data do not include the nature of clinical manifestations or the health outcomes associated with anaplasmosis, babesiosis or Lyme disease.
  • Town level tickborne disease rates are calculated using town level population estimates. Currently, population estimates are unavailable for 2022. As a preliminary solution, 2021 town-level population estimates were used to calculate 2022 rates.

Access Constraints:

Publicly available data are suppressed in accordance with the Maine CDC Privacy Policy to protect confidentiality.

More Information:

Suggested Citation for Data Displays:

Maine Center for Disease Control and Prevention, Maine Tracking Network. Tickborne disease: Incidence. Available online: https://data.mainepublichealth.gov/tracking/.  Accessed on [date accessed].