Lyme disease is transmitted mostly by the nymphal deer tick. At this stage, the ticks are the size of a period at the end of a sentence. Many people are not aware when they’ve been bitten by a tick and may not make a connection when they begin to experience symptoms, which can be weeks, months, or even years after a tick bite. There are published cases of Lyme bacteria entering the human bloodstream within the hour of a bite, and some infections (Powassan Virus) can be transmitted in minutes or hours. This does not happen in every case. The longer the tick is attached, the greater the probability of disease transmission.