Working as a Engineering Tech - we sometimes have to go out into the field with survey crews. I have found that the ONLY thing that ticks cannot penetrate is....pantyhose!!! Those things are the only material that the little suckers seemingly cannot penetrate because of the fine mesh -- so whenever I have to go into the field in summer, I wear hose under my jeans.... works every time --
BUT....can't convince the guys to wear pantyhose! HA!!
I bet many a Civil War soldier had either Rocky Mountain Spotted Fever or Lyme Disease caused by tick bites, but they didn't know what it was back then....