Lyme Disease: Important Facts to Know

What Is Lyme Disease?

Lyme disease is a bacterial infection caused by Borrelia burgdorferi and, rarely, Borrelia mayonii bacteria.

What kind of ticks carry Lyme disease?

Infected backlegged ticks (also called deer ticks) can transmit the bacteria when they bite. The bacteria then travel through your bloodstream. When not treated early, the infection can turn into an inflammatory condition that affects multiple parts of your body, including the skin, joints, and nervous system.

How small are the ticks?

Ticks come in three sizes depending on their stage of life. They can be the size of a grain of sand, a poppy seed, or an apple seed.

What are my chances of getting Lyme disease?

The chances you might get Lyme disease from a tick bite depend on the kind of tick, where you were when it bit you, and how long it was attached. You’re more likely to get Lyme disease if you live in the Northeastern United States. The upper Midwest is also a hot spot. But it affects people in all 50 states and the District of Columbia. The chance of infection is higher the longer an infected tick stays attached, around 36-48 hours.

Which areas are more likely to have Lyme disease?

The tick that causes Lyme disease has been moving from the Northeast and upper Midwest into the Southern and Western U.S., Mexico, and Canada.

According to the CDC, the states with the most reported cases in 2020 were Pennsylvania, New Jersey, New York, Wisconsin, and Maine.

In the Southern U.S., where it’s hotter, ticks stay under leaves so they don't dry out. This means people in the South don’t get Lyme from ticks very often because the ticks don't usually come out to bite.

Even though people only report about 30,000 cases of Lyme infection in the U.S. each year, there are actually around 476,000 a year. The same tick also can spread other diseases, including babesiosis, anaplasmosis, and Powassan virus. Those diseases are also on the rise in the U.S.