The Deer Tick
All
ticks are parasites in that they must locate, attach to, and
feed from an animal or human in each stage of their life cycle.
The deer tick has a two-year life cycle, which can have a direct
bearing on your chances of becoming infected. Adult deer ticks
are active in October-November, and then again in April-May.
They commonly attach to white-tailed deer, dogs, horses, and
people if they are active out of doors in tick prone areas. In
Columbia County, adult ticks may be active anytime the temperature
is over 35 degrees, even with snow on the ground.
In late summer, the larval tick hatches from the egg and feeds on
mice and other small rodents, which serve as the reservoir for
the Lyme disease bacterium. The larva molts to the nymph stage
the following spring.
Nymphs,
which cause most of the cases of Lyme disease (about 80%), occur
in late spring and summer (May through September) and are about
the size of a poppy seed. The nymph waits in ambush on vegetation
from ground level to about 18 inches high. When a host brushes
against the vegetation, the tick clings to it and searches for
a suitable feeding site. By late summer, nymphs molt to the adult
stage, which feed in the fall and spring, and then lay their
eggs and the cycle begins again.