One of the most confusing and controversial dangers to hikers is Lyme disease.
In western North America we did not think much about the risk until we heard of a hiker who got Lyme disease hiking the West Coast Trail — one of the most unlikely geographical locales possible.
Hike aware.
Hard-bodied … ticks are the primary Lyme disease vectors. In Europe, Ixodes ricinus, known commonly as the sheep tick, castor bean tick, or European castor bean tick is the transmitter. In North America, Ixodes scapularis (black-legged tick or deer tick) has been identified as the key to the disease’s spread on the east coast, while on the west coast the primary vector is Ixodes pacificus (Western black-legged tick). Another possible vector is Amblyomma americanum (Lone Star tick), which is found throughout the southeastern U.S. as far west as Texas, and increasingly in northeastern states as well.
The longer the duration of tick attachment, the greater the risk of disease transmission, but, typically, for the spirochete to be transferred, the tick must be attached for a minimum of 12 hours, … Unfortunately only 20% of those infected with Lyme by the deer tick are aware of any tick bite, making early detection difficult in the absence of a rash. Tick bites usually go unnoticed due to the small size of the tick in its nymphal stage, as well as tick secretions that prevent the host from feeling any itch or pain from the bite.
adult tick
I’ve just linked to 
besthike.com 