Lyme Disease
What is it?
Lyme disease is an infection that is caused by
the Borrelia burgdorferi bacterium, which is
transmitted by the bite of the tiny deer tick. It
is called Lyme disease because it was first
diagnosed in Lyme, Connecticut, in 1975. The
organism that causes it was discovered by Willy
Burgdorfer.
Who gets it?
Since it made its appearance in Connecticut,
Lyme disease has been reported in most states, as
well as in other parts of the world. The highest
number of cases, however, have been reported in
the eastern portion of the United States. It is
important to note that not everyone who is bitten
by a tick that carries Borrelia burgdorferi
bacteria will develop Lyme disease, and it cannot
be transmitted from person to person.
What causes it?
Lyme disease is a vector-borne disease. This
means it is transmitted from one host to another.
When a tick carrying the Borrelia burgdorferi
bacterium bites a person, the bacteria enter the
skin and eventually spread through the lymph
system or through the bloodstream. It is the ticks
in the second stage of their development, the
nymph, that are more likely to transmit Lyme
disease to people. The nymphs are less than 2 mm
in size, roughly the size of a pinhead, so they
can attach themselves to the skin and not be
noticed for hours or even days. A tick must feed
on its host's blood for at least 18 to 24 hours in
order to transmit Borrelia burgdorferi. Nymphs are
active from spring through the early summer.
What are the symptoms?
Lyme disease can be localized, meaning it has
not yet spread through the bloodstream or lymph
system, or disseminated, meaning the bacteria have
spread through the body. The first sign of Lyme
disease is usually a red spot, or rash, that
develops around the site of the bite within 3 to
30 days of infection. The rash usually expands so
it looks like a bullseye, with a red spot in the
middle surrounded by a larger red ring. Many
people with Lyme disease also experience flu-like
symptoms, including chills and fever, headache,
fatigue, stiff neck, swollen lymph nodes, and
joint and muscle pain. When the disease is
diagnosed and treated within its early stages,
these types of symptoms usually last from two
weeks to two months. Some people will have periods
where they are symptom-free, followed by flare
ups. When this continues for months or years, it
is called chronic Lyme disease. If Lyme disease is
not treated early, it can become disseminated.
This stage of the disease usually occurs 2 to 12
weeks after a tick bite. Symptoms can include
forgetfulness, confusion, irritability, mood
swings, and fatigue. Some people can develop
abnormalities in their nerve function, resulting
in numbness; unexplained pain; facial paralysis,
or palsy; and an infection of the lining of the
brain, called meningitis.
Although it is less common, some patients
develop heart disorders, including irregular
heartbeats (arrhythmias) and inflammation of the
sac around the heart (pericarditis). The tissues,
muscles, nerves, and cornea of the eye can swell.
Patients who do not receive treatment anywhere
from six weeks to two years after a tick bite,
often because they have no symptoms, are more
likely to develop painful arthritis, which is
inflammation of the joints that leads to swelling
and stiffness. If Lyme disease is treated quickly,
it will not progress beyond the initial symptoms.
How is it diagnosed?
There is no way to grow the Borrelia
burgdorferi bacteria in a culture in a laboratory.
There is also no definitive test for Lyme disease.
A diagnosis is usually made based upon the
patient's symptoms. Doctors will also look closely
at the patient's activities in the period of time
leading up to the symptoms, specifically those
that would expose the patient to a tick bite. A
blood test can reveal an elevated level of
disease-fighting Borrelia burgdorferi antibodies
in the bloodstream. Sometimes, Borrelia
burgdorferi bacteria can be seen in the
cerebrospinal fluid. Cerebrospinal fluid is the
clear fluid found around the brain and spinal
cord. It is removed through a process called a
lumbar puncture, or spinal tap. The area around
the spine is numbed with a local anesthetic. Then,
a long, thin needle is inserted to withdraw a
small sample of fluid for examination under a
microscope.
What is the treatment?
Lyme disease is treated with antibiotics. The
earlier the treatment, the lower the risk of
complications. The most commonly used antibiotics
include doxycycline, amoxicillin, penicillin, and
erythromycin. In the early stages of Lyme disease,
the antibiotics are taken orally, usually for 14
to 21 days. In severe cases, where the disease has
been diagnosed in its later stages or is chronic,
antibiotics may be given intravenously for 14 to
30 days. This means the antibiotic is introduced
directly to the bloodstream through a needle in a
vein. In this case, the antibiotic of choice is
usually ceftriaxone. If the eyes are involved, an
eye specialist may prescribe a corticosteroid to
reduce inflammation and swelling. Arthritis
symptoms are treated with nonsteroidal
anti-inflammatory drugs (NSAIDs), such as
ibuprofen, which are available over-the-counter
and are effective in relieving pain and swelling.
Your doctor will also recommend that you avoid
drinking alcohol and get plenty of rest. It is not
uncommon for people on an extended course of
antibiotics to develop yeast infections. Eating
foods that contain active cultures, such as
yogurt, can help fight yeast infections.
Alternative treatments, such as vitamin and
nutritional supplements, as well as herbal
treatments such as spilanthes, may be helpful in
treating the symptoms of Lyme disease. Check with
your doctor, however, before trying any
alternative therapies. Even with treatment,
Lyme disease symptoms can flare up after months
and even years of exposure.
Self-care tips
It is extremely important to get treatment as
soon as possible if you have been exposed to a
tick bite and begin to have symptoms of Lyme
disease. If you have Lyme disease, follow your
doctor's recommendations for antibiotic treatment,
rest, and nutrition. If you live in an area that
is known to have a large tick population, or spend
a great deal of time in wooded areas, use
precautions to prevent tick bites. Wear light
colored clothing on which ticks are more easily
seen; wear a hat and tuck pant legs into your
socks or boots to keep ticks out; use a tick
repellent that contains the chemical DEET before
going outdoors (if you are using the repellent on
a child, make sure it is child safe); and check
yourself and any children for ticks frequently,
particularly around the ankles, neck, armpit,
groin, behind the ears, and on the scalp. If you
do find a tick on yourself or your child, remove
the tick as quickly as possible. Use tweezers to
grasp the tick as close to the skin as possible,
then pull it straight out in a gentle, steady
motion. Do not squeeze the tick so hard that you
crush it, and do not jerk or twist, or you will
not remove the entire tick.
While many people believe you can make a tick
come out by using a lit match, petroleum jelly, or
alcohol, this is actually not a good idea and may
make the tick more difficult to remove. Keep the
removed tick in a closed container if you want to
have it identified, or just flush it down the
toilet. It's also a good idea to use a tick
defense treatment on your dog if he or she spends
a lot of time outdoors in an area that is known to
have a large tick population. Despite all the
media attention, the possibility of developing
Lyme disease, even after being bitten by a deer
tick, is actually very low.
This information has been designed as a comprehensive and quick reference
guide written by our health care reviewers. The health information written
by our authors is intended to be a supplement to the care provided by your
physician. It is not intended nor implied to be a substitute for
professional medical advice.
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