Lyme disease is a
bacterial infection that features a skin
rash, swollen joints and flu-like
symptoms. You get the disease from the
bite of an infected tick. Sometimes it
is hard to know if you have Lyme disease
because you may not have noticed a tick
bite. Also, many of its symptoms are
like those of other diseases. Symptoms
- A skin rash, often resembling a
- Muscle pain
- Stiff neck
- Swelling of knees and other
In the early stages, doctors look at
your symptoms and medical history to
figure out whether you have Lyme
disease. In the later stages of the
disease, lab tests can confirm whether
you have it.
Antibiotics usually cure early stage
Lyme disease. If not treated, the
disease can cause problems with the
joints, heart and nervous system.
In the early 1970s, a mysterious clustering of arthritis
cases occurred among children in Lyme, Connecticut, and
surrounding towns. Puzzled medical experts eventually
labeled the illness as a new disease, which they called
Lyme disease. By the mid-1970s, scientists were busy
describing signs and symptoms of Lyme disease to help
doctors diagnose patients. Scientists eventually learned
that antibiotics were an effective treatment, and that
the bite of the deer tick was the key to the spread of
None of these findings, however, happened overnight. In
fact, it wasn’t until 1981—through a bit of puzzle
solving and keen recollection—that the cause of Lyme
disease was identified and the connection between the
deer tick and the disease was discovered.
Lyme disease is still mistaken for other illnesses, and
it continues to pose many other challenges, including
It can be difficult to diagnose.
It can be hard to treat in its later phases.
A number of different ticks can transmit diseases with
symptoms like Lyme disease.
Deer ticks can pass on diseases other than Lyme disease.
This booklet presents the most recently available
information on the diagnosis, treatment, and prevention
of Lyme disease.
How Lyme DiseaseBecame Known
Lyme disease was first recognized in 1975 after
researchers tried to find out why unusually large
numbers of children were being diagnosed with juvenile
rheumatoid arthritis in Lyme, Connecticut, and two
neighboring towns. After considering several possible
causes, such as contact with germs (microbes) in water
or air, researchers focused their attention on deer
ticks. They realized that most of the affected children
lived and played near wooded areas.
Researchers knew that the children’s first symptoms
typically started during summer—the height of tick
season. Several of the children reported having a skin
rash just before developing their arthritis. Many of
them recalled being bitten by a tick where the rash
Before Lyme Disease Became Known
Around the same time, about 2,500 miles away from Lyme,
Willy Burgdorfer, Ph.D., was conducting research at
Rocky Mountain Laboratories (RML) in Hamilton, Montana,
part of the National Institute of Allergy and Infectious
Diseases (NIAID). Dr. Burgdorfer was studying Rocky
Mountain spotted fever, which is also caused by the bite
of a tick.
In the summer of 1977, Allen C. Steere, M.D., was
investigating the Lyme disease cases for the Yale
University School of Medicine in Hartford, Connecticut.
During conversations with Dr. Burgdorfer, Dr. Steere
mentioned the deer tick as the likely carrier for Lyme
Researchers in Europe had written about a skin rash
similar to that of Lyme disease in medical literature
dating back to the turn of the 20th century. Dr.
Burgdorfer wondered if the European rash, called
erythema migrans, and Lyme disease might have the same
As Dr. Burgdorfer and his RML colleague Alan Barbour,
M.D., continued to study spiral-shaped bacteria, or
spirochetes, from infected deer ticks, they eventually
achieved success. In late November 1981, the scientists
found the cause of both Lyme disease and the European
skin rash. The spirochete was later named Borrelia
burgdorferi in honor of Dr. Burgdorfer for his role in
Although Lyme disease may have spread from Europe to the
United States in the early 1900s, health experts only
recently recognized it as a distinct illness.
Small rodents and deer play an important role in a deer
tick’s life cycle. Today, scientists who study Lyme
disease are learning much more about that role.
Both nymphs (immature ticks) and adult ticks can
transmit Lyme disease-causing bacteria. The recent
increase of the deer population in the Northeast, and of
in rural areas where deer ticks are commonly found,
probably have contributed to the spread of the disease.
The numbers of cases of Lyme disease and of geographic
areas in which it is found have increased. Healthcare
providers have seen cases of Lyme disease in nearly all
states in the United States. However, most reported
cases are concentrated in the coastal Northeast, the
mid-Atlantic states, Wisconsin, Minnesota, and northern
California. Lyme disease is also found in large areas of
Asia and Europe.
Symptoms of Lyme Disease
Erythema migrans (EM) is usually the first symptom of
• The telltale rash starts as a small red spot at the
site of the tick bite.
• The spot gets larger over a period of days or weeks
and forms a red rash shaped like a circle or an oval.
Sometimes the rash looks like a bull’s eye, appearing as
a red ring surrounding a clear area with a red center.
The rash, which can range in size from that of a small
coin to the width of your back, appears within a few
weeks of a tick bite and usually at the place of the
bite. As infection spreads, rashes can appear at
different places on the body.
Other symptoms that often appear with EM can include:
• Stiff neck
• Body aches
Although these symptoms may be like those of common
viral infections such as the flu, Lyme disease symptoms
tend to continue longer or may come and go.
After several months of infection with Lyme bacteria,
slightly more than half of people not treated with
antibiotics develop recurrent attacks of painful and
swollen joints. These attacks last a few days to a few
months. The arthritis can move from one joint to
another. The knee is most commonly affected.
About 10 to 20 percent of people who have not taken
antibiotics will go on to develop chronic (long-lasting)
Lyme disease can also affect your nervous system,
causing symptoms such as the following:
• Stiff neck and severe headache (meningitis)
• Temporary paralysis of your facial muscles (Bell’s
• Numbness, pain, or weakness in your limbs
• Poor muscle movement
Lyme disease can also cause more subtle changes such as
• Memory loss
• Difficulty with concentration
• Change in mood or sleep habits
usually develop several weeks, months, or even years
following untreated infection. These symptoms often last
for weeks or months and may return.
Less commonly, people who have not taken antibiotics may
develop heart or other problems weeks, months, or even
years after they were infected with Lyme bacteria.
Fewer than 1 out of 10 people with Lyme disease develop
heart problems, such as irregular heartbeat, which can
start with dizziness or shortness of breath. These
symptoms rarely last more than a few days or weeks. Such
heart problems generally show up several weeks after a
person is infected with Lyme bacteria.
Less commonly, Lyme disease can cause eye inflammation,
hepatitis (liver disease), and severe fatigue. None of
these problems, however, is likely to appear without
other Lyme disease symptoms being present.
Disease Is Diagnosed
Your healthcare provider may have difficulty diagnosing
Lyme disease because many of its symptoms are similar to
those of other illnesses. In addition, the only symptom
that is unique to Lyme disease is the rash. That rash is
absent in at least one-fourth of the people who become
The results of recent research studies show that an
infected tick must be attached to the skin for at least
2 days to transmit Lyme bacteria. Although a tick bite
is an important clue for diagnosis, many people cannot
recall having been bitten recently by a tick. This is
not surprising because the deer tick is tiny, and a tick
bite is usually painless.
If you have Lyme disease symptoms, but do not develop
the distinctive rash, your healthcare provider will rely
on a detailed medical history and a careful physical
exam for clues to diagnose it. You will also be given
laboratory tests to help diagnose the disease.
If you don’t have the EM rash, your healthcare provider
will diagnose Lyme disease based on
• Whether your symptoms first appeared during the summer
months when tick bites are most likely to occur
• Whether you were outdoors in an area where Lyme
disease is common
• Whether you have been bitten by a tick
• Whether you have other symptoms of Lyme disease
In addition, your healthcare provider will rule out
other diseases that might be causing your symptoms.
It is difficult for healthcare providers to find the
bacterium that causes Lyme disease in lab tests of body
tissues or fluids. Therefore, most look for evidence of
antibodies against B. burgdorferi in the blood to
confirm that the bacterium is causing the symptoms.
Healthcare providers cannot always find out whether Lyme
disease bacteria absolutely are causing symptoms. In the
first few weeks following infection, antibody tests are
not reliable because your immune system has not produced
enough antibodies to be found. Antibiotics given early
during infection may also prevent antibodies from
reaching levels that a test can find, even though Lyme
disease bacteria are causing your symptoms.
The antibody test most often used is called an ELISA
(enzyme-linked immunosorbent assay) test. The Food and
Drug Administration (FDA) has approved two antibody
• Prevue B, a rapid test, can give results within an
• The C6 Lyme Peptide ELISA is very sensitive and
If your ELISA is positive, your healthcare provider
should confirm it with a second, more specific test
called a Western blot.
If you have nervous system symptoms, you may also get a
spinal tap. Using this test, your healthcare provider
can find any inflammation in your brain and spinal cord
and can look for antibodies or genetic material of
B. burgdorferi in your spinal fluid.
FDA has not approved tests for Lyme disease that use
urine or some other body fluids to diagnose infection
caused by Lyme bacteria.
New Tests Being Developed
Healthcare providers need tests to tell apart people who
have recovered from previous Lyme infection and those
who continue to suffer from active infection.
To improve the accuracy of diagnosing Lyme disease,
National Institutes of Health (NIH)-supported
researchers are re-evaluating current tests. They are
also developing a number of new tests that promise to be
more reliable than those currently available.
NIH-supported scientists are developing tests that use
the highly sensitive genetic engineering technique known
as PCR (polymerase chain reaction) as well as microarray
and high-throughput genomic sequencing technology to
detect extremely small quantities of the genetic
material of the Lyme disease bacterium or its products
in body tissues and fluids.
A bacterial protein, outer surface protein (Osp) C, is
proving useful for detecting specific antibodies early
in people with Lyme disease. Because researchers have
determined the genome of B. burgdorferi, there are now
new avenues for improving their understanding of the
disease and its diagnosis.
How Lyme Disease Is Treated
Using antibiotics appropriately, your healthcare
provider can effectively treat your Lyme disease. In
general, the sooner you begin treatment after you have
been infected, the quicker and more complete your
Antibiotics such as doxycycline, cefuroxime axetil, or
amoxicillin, taken orally for a few weeks, can speed the
healing of the EM rash and usually prevent symptoms such
as arthritis or neurological problems.
Doctors usually treat Lyme disease in children younger
than 9 years, or in pregnant or breast-feeding women,
with amoxicillin, cefuroxime axetil, or penicillin. They
do not use doxycycline in these groups because the
antibiotic can stain the permanent teeth developing in
young children or unborn babies.
If you have Lyme arthritis, your healthcare provider may
treat you with oral antibiotics. If your arthritis is
severe, you may be given ceftriaxone or penicillin
intravenously (through a vein). To ease any discomfort
and to help with healing, your healthcare provider might
also do one of the following:
• Give you anti-inflammatory drugs
• Draw fluid from your affected joints
• Perform surgery to remove the inflamed lining of those
In most people, Lyme arthritis goes away within a few
weeks or months following antibiotic treatment. In some,
however, it can take years to disappear completely. Some
people with Lyme disease who are untreated for several
years may be cured of their arthritis with the proper
The disease, however, does not always go away with
treatment. If it has lasted long enough, it may
permanently damage the structure of your joints.
If you have neurological symptoms, your healthcare
provider will probably treat you with the antibiotic
ceftriaxone given intravenously once a day for a month
or less. Most people recover completely.
Healthcare providers prefer to treat people with Lyme
disease who have heart symptoms with antibiotics such as
ceftriaxone or penicillin given intravenously for about
2 weeks. People with Lyme disease rarely have long-term
Problems After Treatment
Following treatment for Lyme disease, you might still
have muscle aches, and neurological problems such as
tiredness and trouble with memory and concentration.
NIH-sponsored researchers are doing research to find out
the cause of these symptoms and the best ways to treat
them. Research studies suggest that people who suffer
from post-Lyme disease symptoms may be genetically
predisposed to develop an autoimmune response that
contributes to their symptoms. Researchers are now
examining the significance of this finding in greater
Researchers also are trying to find out the best length
of time to give antibiotics for the various symptoms of
Unfortunately, having a bout with Lyme disease once is
no guarantee that you will not get the illness again. It
can strike more than once if you are reinfected with
Lyme disease bacteria.
How Lyme Disease Is Prevented
At present, the best way you can avoid Lyme disease is
to avoid deer ticks. Although generally only about 1
percent of all deer ticks are infected with Lyme disease
bacteria, in some areas more than half of the ticks have
More people with Lyme disease become infected during the
summer, when immature ticks are found most often. In
warm climates, deer ticks thrive and bite during the
winter months as well.