Lyme Disease Causes
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 doctor 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.
Lyme disease is found most often in three geographic locations in the US. 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.
- Southern US—Ticks are active year-round.
- Other areas can be variable, based on the temperature.
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. Wear full length clothes and closed shoes for protection.
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.
American Lyme Disease Foundation website. Available at:
Griffith's 5-Minute Clinical Consult.10th ed. Lippincott Williams & Wilkins; 2001.
Lyme Disease Foundation website. Available at:
National Institute of Allergy and Infectious Diseases website. Available at: