In 2015, 95% of confirmed Lyme disease cases were reported from 14 states:
- Connecticut
- Delaware
- Maine
- Maryland
- Massachusetts
- Minnesota
- New Hampshire
- New Jersey
- New York
- Pennsylvania
- Rhode Island
- Vermont
- Virginia
- Wisconsin
These states have areas where infected ticks are common. Infected ticks can also be found in neighboring states and in some areas of Northern California, Oregon and Washington.
Although Lyme disease cases are occasionally reported from most other states, this does NOT mean that infection was acquired in those states. Case reports reflect where a patient lives at the time of diagnosis, which can be different from the state where the patient was infected.
Lyme disease is the most commonly reported vectorborne illness in the United States. In 2015, it was the sixth most common Nationally Notifiable disease.