The Two Year Life-Cycle Of The Deer Tick
Life-cycle of Ixodes scapularis(a.k.a. blacklegged or deer tick) in the northeast/mid-Atlantic/upper mid-western United States.
Larval deer ticks are active in August and September but these ticks are pathogen-free. Ticks become infected with pathogens
when larvae (or nymphs) take a blood meal from infectious animal hosts. Engorged larvae molt over winter and emerge in May as
poppy-seed sized nymphal deer ticks. Please note that most cases of Lyme disease are transmitted from May through July, when
nymphal-stage ticks are active. Adult-stage deer ticks become active in October and remain active throughout the winter whenever
the ground is not frozen. Blood-engorged females survive the winter in the forest leaf litter and begin laying their 1,500 or
more eggs around Memorial Day (late May). These eggs hatch in July, and the life-cycle starts again when larvae become active