Not all deer ticks are infected with the bacteria that cause Lyme disease.
Ticks can become infected if they feed on small animals that are infected.
The disease can be spread when a tick infected with the bacteria bites a person and stays attached for a period of time. Lyme disease cannot be spread from one person to another. Lyme disease can affect people of any age. People who spend time in grassy and wooded environments are at an increased risk of exposure. The chances of being bitten by a deer tick are greater during times of the year when ticks are most active.