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| Center for Disease Control and Prevention. Lyme Disease Q & A.
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Questions and Answers About Lyme Disease
Questions and Answers About Lyme Disease. Center for
Disease Control and Prevention.
Q. How do people get Lyme disease?
A. By the bite of ticks infected with Lyme disease bacteria. (Deer tick)
Q. What is the basic transmission cycle?
A. Immature ticks become infected by feeding on small rodents, such as the
white-footed mouse, and other mammals that are infected with the bacterium
Borrelia burgdorferi. In later stages, these ticks then transmit the Lyme
disease bacterium to humans and other mammals during the feeding process. Lyme
disease bacteria are maintained in the blood systems and tissues of small
rodents.
Q. Could you get Lyme disease from another person?
A. No, Lyme disease bacteria are NOT transmitted from person-to-person. For
example, you cannot get infected from touching or kissing a person who has Lyme
disease, or from a health care worker who has treated someone with the disease,
or by sexual contact.
Q. What are the signs and symptoms of Lyme disease?
A. Within days to weeks following a tick bite, 80% of patients will have a red,
slowly expanding "bull's-eye" rash (called erythema migrans), accompanied by
general tiredness, fever, headache, stiff neck, muscle aches, and joint pain. If
untreated, weeks to months later some patients may develop arthritis, including
intermittent episodes of swelling and pain in the large joints; neurologic
abnormalities, such as aseptic meningitis, facial palsy, motor and sensory nerve
inflammation (radiculoneuritis) and inflammation of the brain (encephalitis);
and, rarely, cardiac problems, such as atrioventricular block, acute
inflammation of the tissues surrounding the heart (myopericarditis) or enlarged
heart (cardiomegaly).
Q. What is the incubation period for Lyme disease?
A. For the red "bull's-eye" rash (erythema migrans), usually 7 to 14 days
following tick exposure. Some patients present with later manifestations without
having had early signs of disease.
Q. What is the mortality rate of Lyme disease?
A. Lyme disease is rarely, if ever, fatal.
Q. Can a person be reinfected with Lyme disease?
A. Yes. Having had Lyme disease doesn't protect against reinfection. Some
persons have had Lyme disease more than once after re-exposure to infective tick
bites. This stresses the need for continued tick bite prevention activities such
as wearing appropriate clothing when in tick-infested areas, daily tick checks,
and quick removal of attached ticks.
Q. How many cases of Lyme disease occur in the U.S.?
A. Lyme disease is the leading cause of vector-borne infectious illness in the
U.S. with about 15,000 cases reported annually, though the disease is greatly
under reported. Based on reported cases, during the past ten years 90% of cases
of Lyme disease occurred in ten states: More information can be found in the
MMWR, March 16, 2001 / 50(10);181-5 (http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5010a1.htm).
| State |
Total Number Cases
Reported 1989-1998 |
Annual Incidence per
100,000 persons |
| New York |
39,370 |
21.6 |
| Connecticut |
17,728 |
54.2 |
| Pennsylvania |
14,870 |
12.3 |
| New Jersey |
13,428 |
16.9 |
| Wisconsin |
4,760 |
9.3 |
| Rhode Island |
3,717 |
37.5 |
| Maryland |
3,410 |
6.8 |
| Massachusetts |
2,712 |
4.5 |
| Minnesota |
1,745 |
3.8 |
| Delaware |
1,003 |
14.0 |
Q. How is Lyme disease treated?
A. According to treatment experts, antibiotic treatment for 3-4 weeks with
doxycycline or amoxicillin is generally effective in early disease. Cefuroxime
axetil or erythromycin can be used for persons allergic to penicillin or who
cannot take tetracyclines. Later disease, particularly with objective neurologic
manifestations, may require treatment with intravenous ceftriaxone or penicillin
for 4 weeks or more, depending on disease severity. In later disease, treatment
failures may occur and retreatment may be necessary. (The Medical Letter, Vol.
42(Issue 1077), May 1, 2000)
Q. Is the disease seasonal in its occurrence?
A. Yes, Lyme disease is most common during the late spring and summer months in
the U.S. (May through August) when nymphal ticks are most active and human
populations are frequently outdoors and most exposed.
 Map:
Reported cases of Lyme disease in the United States, 1999.
Q. Where is Lyme disease most common?
A. Click on the map at right that shows reported cases of Lyme disease in 1999
by patient's county of residence. Generally, most Lyme disease is endemic in the
northeastern and upper midwest states. (See "Lyme Disease—United States, 1999."
MMWR. March 16, 2001;50:181-185.)
Q.Who is at risk for getting Lyme disease?
A. Persons in endemic areas who frequent sites where infected ticks are common,
such as grassy or wooded locations favored by white-tailed deer in the
northeastern and upper midwest states, and along the northern Pacific coast of
California.
Q. Is there a vaccine against Lyme disease?
A. As of February 25, 2002 the manufacturer announced that the LYMErix™ Lyme
disease vaccine will no longer be commercially available.
Q. Does the Lyme disease vaccine cause arthritis? Are individuals with
certain HLA-DR4 genetic subtypes more susceptible to getting arthritis from the
vaccine?
A. An association between naturally acquired treatment-resistant Lyme disease
arthritis, certain HLA-DR4 genetic subtypes, and high levels of antibody to OspA
of naturally acquired Borrelia burgdorferi has been described in the medical
literature (1, 2, 3). Because of the relationship between OspA antibodies and
treatment-resistant arthritis from naturally acquired infection, CDC’s Advisory
Committee on Immunization Practices (ACIP) has stated that the vaccine should
not be given to persons with treatment-resistant Lyme arthritis (4). However, at
this writing there is no scientific evidence that the currently licensed Lyme
disease vaccine increases the recipient’s risk of arthritis. To the contrary,
there is good evidence that the risk of arthritis in vaccine recipients is not
significantly different from the risk in individuals who have received placebo
without OspA (5). ACIP has not recommended screening of HLA type prior to
vaccination. In the absence of evidence that the vaccine causes arthritis,
screening for HLA-DR4 subtypes before vaccination would not seem to be a
beneficial use of health resources.
1. Kalish RA, Leong JM, Steere AC. Association of treatment-resistant
chronic Lyme arthritis with HLA-DR4 and antibody reactivity to OspA and OspB of
Borrelia burgdorferi. Infect Immun 1993;61:2774-2779.
2. Akin E, McHugh GL, Flavell RA, et al. The immunoglobulin (IgG) antibody
response to OspA and OspB correlates with severe and prolonged Lyme arthritis
and the IgG response to p35 correlates with mild and brief arthritis. Infect
Immun 1999;173-181.
3. Gross DM, Forsthuber T, Tary-Lehmann M, et al. Identification of LFA-1
as a candidate autoantigen in treatment-resistant Lyme arthritis. Science
1998;281:703-706.
4. Centers for Disease Control and Prevention. Recommendations for the Use
of Lyme Disease Vaccine - Recommendations of the Advisory Committee on
Immunization Practices. MMWR 1999;48:1-17.
(Also available in PDF format [742 KB, 39 pages].)
5. Steere AC, Sikand VK, Meurice F, et al. Vaccination against Lyme
disease with recombinant Borrelia burgdorferi outer-surface lipoprotein A with
adjuvant. N Engl J Med 1998;339:209-216.
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