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COMMON NAME:
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Blacklegged/deer/bear tick
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SCIENTIFIC NAME:
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Ixodes scapularis Say
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CLASS/ORDER/FAMILY:
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Arachnida/Acari/Ixodidae
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METAMORPHOSIS:
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Simple
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The common name
blacklegged refers to their dark legs which are in contrast to the paler body
and that of deer because the preferred adult host is the white-tailed deer; in
the midwest, it is called the bear tick. This tick is of medical importance
because it is an important vector of Lyme disease. Blacklegged ticks are found
primarily in the northeastern, midwestern, and southeastern states in the United
States, but extend into Mexico.Blacklegged/deer ticks climb grass and shrubs to
wait for a passing host, and move very little laterally. They concentrate on
such vegetation located in transitional areas/zones such as where forest meets
field, mowed lawn meets unmowed fence line, a foot/animal trail through high
grass or forest, etc. Because these transitional areas or edge habitats are
where most animals travel sometime each 24-hour period, this is where the ticks
are mostly likely to acquire a host.
The other habitat most likely to harbor ticks is the den, nest, or nesting area
of its host such as that of skunks, raccoons, opossums, but especially the
white-footed mouse. The white-footed mouse prefers woody or brushy areas. It
nests in any place that gives shelter such as below ground, in stumps, logs, old
bird or squirrel nests, woodpiles, buildings, etc. A favorite feeding area for
these ticks on humans is at the back of the neck, at the base of the skull; long
hair makes detection more difficult. However, the ticks will usually wonder
about for up to 4 hours or so before they attach. Then, a tick has to be
attached for a period of 6-8 hours before a successful transmission can take
place.
Most ticks spend the bulk of their life on or near the ground, waiting for a
suitable host animal. Since they cannot run, hop, fly or move quickly,
ticks must climb onto an appropriate object such as tall grass or weeds or up
onto fences and siding of buildings. It is from these advantageous
positions that they wait for a suitable host to pass by. When they detect
vibrations and chemical cues such as host odors or exhaled carbon dioxide, ticks
will fall from their perch or stretch out (holding on to their perch with only 2
or 4 of their rear legs) and hope to snag or attach onto a passing host (e.g., a
mammal with a fur coat or pants and socks worn by humans.) Ticks are
also capable of detecting shadows cast by a passing host. These tick
behaviors are important to understand and recognize in order to make thorough
and effective applications of acaricides, pesticide dusts or sprays labeled for
eliminating ticks and other arachnids. These behaviors also explain why
ticks crawl up exterior or interior surfaces of homes and often lodge in cracks
and crevices below shingles, clapboard siding, window molding, baseboards, etc.
In these latter cases, you must understand this aspect of tick behavior and
carefully inspect and treat all these crack and crevices with a good insecticide
dust.
- Sanitation, consists
of the following: (a) keep grass cut low including around fence lines, sheds,
trees, shrubs, swing sets and other difficult to cut locations; (b) remove
weeds, woodpiles, and other debris which are attractive to mice as nesting
areas, and leaf litter which is attractive to ticks, especially the nymphs;
(c) keep garbage can lids on tightly to discourage opossums, raccoons, and
skunks from coming into the yard to raid garbage cans for food because these
animals all harbor the ticks which transmit the Lyme disease pathogen; (d)
discourage feeding birds because the seeds attract deer mice, the major
reservoir host for the Lyme disease pathogen; and (e) install a chimney screen
to keep squirrels, raccoons, and birds away.
- Personal protection,
consists of: (a) use deet or permethrin containing repellent and tuck pants
into socks or boots when going into suspect areas; (b) check children for
ticks when they come into the house because it takes up to 4 hours, possibly
longer, for the tick to start feeding; (c) wear light colored clothing which
makes spotting ticks easier; (d) pets which go outdoors may increase the
chance of the occupant's encounter with these ticks, especially cats; and (e)
encourage the vet to check any pet's blood to determine if they are carrying
the Lyme disease spirochete.
- Inspection, is done
by performing a tick drag on a routine basis in areas where the ticks have
been reported or for homes adjacent to heavily wooded or uninhabited areas.
The drag consists of light colored heavy duty cloth, 7 feet long by 2 feet
wide, which is securely weighted at both ends. A rope is attached to one end
and this drag is walked around the suspect property.
LYME DISEASE.
The symptoms are usually divided into 3 stages, and they mimic several different
commonly occurring diseases. Symptoms: Spreading rash, fever, flu-like symptoms,
aches.
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Stage 1: |
Expanding rash (Erythema migrans or EM rashes). 3-30 days after bite. |
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Ringlike/bullseyelike
appearance to rash.
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One or more rash sites.
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May or may not have flu symptoms.
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May come and go or persist. |
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Stage 2: |
Complications or disorders of the heart or nervous system. |
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Heart. Varying degrees of blockage of the heart muscle.
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Nervous system. Meningitis, encephalitis, facial paralysis.
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"Bell's palsy," other conditions involving peripheral nerves.
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Migratory pain in joints, tendons, muscles, and bones, often without
joint swelling or redness. |
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Stage 3: |
Months to years after disease onset. |
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Arthritis that appears and disappears intermittently for several years.
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Enlarged knee joints.
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Erosion of cartilage and bone. |
The best way to
remove a tick is by using special forceps. You can buy these in every drugstore.
With these modified tweezers you can grab the tick by the head, as close to your
skin as possible. With a rotating motion the tick can be pulled out. The special
forceps make it much easier to rotate than normal tweezers. Make sure that no
parts of the tick's mouth-parts break off and remain in your skin.
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