These tiny ticks can cause some big problems. Both varieties, deer and nymphal ticks, have the potential to carry and transmit Lyme disease to a human host. Some people believe that Lyme disease is so particular about its deer tick host because it was manufactured to be that way. Yes, by actual manufacturing by men in a laboratory on Plum Island, New York. (Beginning in the 1950s, the U.S. government began conducting biological warfare research there.) Some conspiracy theorists think it's no coincidence that the first outbreak of Lyme disease was in Lyme, CT, some 20 miles from Plum Island.