The most important host is the white-footed mouse. If the host is infected with the bacterium that causes Lyme disease, the larvae may become infected. Nymphs, which have eight legs and are the size of a pin head, are the least particular about their host. This stage, present in the summer, is the most likely to bite humans. It does take a tick several hours to attach itself to a body and 12 to 48 hours for an infected, feeding tick to transmit the Lyme disease bacterium.
Ticks molt into mature adults in the fall.
Adult ticks are twice as likely as larvae to have the bacterium because they have had two blood meals. However, the normal host of this stage is the white-tailed deer. If no deer are present, ticks may feed on a cow, horse, dog or human. In addition, this stage is associated with fewer cases of Lyme disease, partly because the ticks are larger and easier to spot and remove prior to transmission of the bacterium. Wear long sleeves and long pants tucked into boots or socks.