What Is Lyme Disease?

Lyme disease is an infection that's spread by Ixodes (pronounced: iks-oh-deez) ticks (black-legged or deer ticks in the eastern United States, and western black-legged ticks in the west) that carry the bacterium Borrelia burgdorferi. These ticks acquire the bacteria from mice and then infect humans by biting them and passing the bacteria into a person's bloodstream. Sound gross? Maybe, but you can be sure that you won't witness this process: the ticks themselves are extremely difficult to detect. Immature ticks, or nymphs, are about the size of a poppy seed; adult ticks are about the size of a sesame seed.
Because the ticks are hard to find, it's important to be aware of the symptoms of Lyme disease. It's easy to overlook a tick bite. Many people who get Lyme disease don't remember getting bitten. The good news is that most tick bites don't result in Lyme disease.