A risk factor is something that increases your likelihood of getting a disease or condition.

It is possible to develop Lyme disease with or without the risk factors listed below. However, the more risk factors you have, the greater your likelihood of developing Lyme disease. If you have a number of risk factors, ask your healthcare provider what you can do to reduce your risk.

Anyone who lives in an area where there are ticks has a risk of being bitten by a Lyme disease-infected tick. An increased risk is usually directly related to the amount of time a person spends outdoors in areas where there are a lot of ticks.

Geographic Location

Lyme disease is found most often in three geographic locations in the United States. These are:

  • The northeastern and mid-Atlantic region: Maine to Maryland
  • The upper north-central region: Minnesota and Wisconsin
  • The northwest: northwestern California and Oregon

Time of Year

Ticks are most active during the warmer months of the year. Peak at-risk times vary from region to region, based on the temperature.

  • Northeast and north-central US – Increased risk is between April and November, with the peak occurring in July.
  • West coast – The risk is higher between November and April.
  • Non-coastal Western States – The risk is higher between January and May.
  • Southern US – Ticks are active year-round.


People who work outdoors in jobs such as surveying, landscaping, forestry, gardening, and utility service have a higher risk of Lyme disease. Participating in outdoor recreational activities such as hiking, camping, hunting, and gardening can also increase your risk.


The ticks that carry Lyme disease are more likely to live in wet, green, brushy, or wooded areas. They are less likely to be near pruned, well-cared-for plants, but more likely near unmaintained shrubby or brushy plants. Living near or visiting wooded or brushy areas can increase your risk.


Lyme disease occurs more often in children under age 15, and adults between 25-44 years old. This is most likely due to outdoor activities that expose them to ticks.