Lyme disease is a bacterial illness caused by a bacterium called a "spirochete." The actual name of the bacterium is Borrelia burgdorferi. Lyme disease is spread by ticks when they bite the skin permitting the bacterium to infect the body. Lyme disease can cause abnormalities in the skin, joints, heart and nervous system.
In the United States, Lyme disease is mostly localized to states in the northeastern, mid-Atlantic, and upper north-central regions, and to several counties in Northwestern California. In 1999, 16,273 cases of Lyme disease were reported to the Centers for Disease Control and Prevention (CDC). Ninety-two percent of these were from the states of Connecticut, Rhode Island, New York, Pennsylvania, Delaware, New Jersey, Maryland, Massachusetts, and Wisconsin.
Following are some prevention tips and information about what to do if you believe you may be infected:
- Avoid tick habitats: Whenever possible, avoid entering areas that
are likely to be infested with ticks, particularly in spring and summer when
nymphal ticks feed. Ticks favor a moist, shaded environment, especially
areas with leaf litter and low-lying vegetation in wooded, brushy or
overgrown grassy habitat. Both deer and rodent hosts must be abundant to
maintain the enzootic cycle of B. burgdorferi. Sources for
information on the distribution of ticks in an area include state and local
health departments, park personnel, and agricultural extension services.
- Use personal protection measures: If you are going to be in areas
that are tick infested, wear light-colored clothing so that ticks can be
spotted more easily and removed before becoming attached. Wearing
long-sleeved shirts and tucking pants into socks or boot tops may help keep
ticks from reaching your skin. Ticks are usually located close to the
ground, so wearing high rubber boots may provide additional protection.
The risk of tick attachment can also be reduced by applying insect repellents containing DEET (n,n-diethyl-m toluamide) to clothes and exposed skin, and applying permethrin (which kills ticks on contact) to clothes. DEET can be used safely on children and adults but should be applied according to Environmental Protection Agency (EPA) guidelines to reduce the possibility of toxicity.
- Perform a tick check and remove attached ticks: The transmission of
B. burgdorferi (the bacteria that causes Lyme disease) from an infected tick
is unlikely to occur before 36 hours of tick attachment. For this reason,
daily checks for ticks and promptly removing any attached tick that you find
will help prevent infection. Embedded ticks should be removed using
fine-tipped tweezers. DO NOT use petroleum jelly, a hot match, nail
polish, or other products. Grasp the tick firmly and as closely to the skin
as possible. With a steady motion, pull the tick's body away from the skin.
The tick's mouthparts may remain in the skin, but do not be alarmed. The
bacteria that cause Lyme disease are contained in the tick's midgut. Cleanse
the area with an antiseptic.
- Taking preventive antibiotics after a tick bite: The relative
cost-effectiveness of post-exposure treatment of tick bites to avoid Lyme
disease in endemic areas (areas where the disease is known to occur
regularly) is dependent on the probability of B. burgdorferi infection after
a tick bite. In most circumstances, treating persons who only have a tick
bite is not recommended. Individuals who are bitten by a deer tick should
remove the tick and seek medical attention if any signs and symptoms of
early Lyme disease, ehrlichiosis, or babesiosis develop over the ensuing
days or weeks.
- Strategies to reduce tick abundance: The number of ticks in endemic
residential areas may be reduced by removing leaf litter, brush- and
wood-piles around houses and at the edges of yards, and by clearing trees
and brush to admit more sunlight and reduce the amount of suitable habitat
for deer, rodents, and ticks. Tick populations have also been effectively
suppressed through the application of pesticides to residential properties.
Community-based interventions to reduce deer populations or to kill ticks on
deer and rodents have not been extensively implemented, but may be effective
in reducing the community-wide risk of Lyme disease. New approaches such as
deer feeding stations equipped with pesticide applicators to kill ticks on
deer, and baited devices to kill ticks on rodents, are currently under
- Early diagnosis and treatment: The early diagnosis and proper antibiotic treatment of Lyme disease are important strategies to avoid the morbidity and costs of complicated and late-stage illness.
For more information, please visit MedicineNet.com's Lyme Disease Center.
Portions of the above information was provided with the kind permission of the Centers for Disease Control.
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Last Editorial Review: 12/28/2004