For the first time, researchers have confirmed the existence of deer ticks at nine national parks in the eastern United States.

The survey of nine parks — including Acadia National Park in Maine, Fire Island National Seashore in New York, Gettysburg National Military Park in Pennsylvania and Shenandoah National Park in Virginia — is the first large-scale survey of this type.

Analysts say while the presence of the black-legged tick has long been suspected, it had not been previously confirmed.

They add ticks infected with Lyme disease are present in other parks in areas where Lyme disease cases are prevalent.

The National Park Service advises visitors to use insect repellent continuing deet and apply it to exposed skin and clothing, as well as check yourself, your pets and your gear for ticks and remove any on yourself or your pet.

If you get ticks on your clothing, you can kill them by throwing the clothes in the dryer at high heat for 10 minutes.

Findings appear in the Journal of Medical Entomology.