The Story of the Lyme Disease Vaccine
Scientists discovered the microbe that causes Lyme disease
and contributed other insights that led to the production of a safe and
effective vaccine for the prevention of Lyme disease. This achievement emphasizes
the importance of basic research in providing knowledge to mount a timely
response to emerging diseases.
Lyme Disease: The Timeline of Its Discovery and the
Development of a Vaccine
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1975 First cases
of Lyme disease reported.
1981 Microbe identified.
1989 The outer surface protein,
OspA, found and cloned.
Early 1990s Antibodies to OspA
found in many chronic Lyme disease patients.
1990-1992 Vaccinations with rOspA
found to protect mice against Lyme disease infection.
1992-1995 Vaccinations with rOspA
tested in other animals.
1995 Lyme vaccine found safe and
effective in persons with Lyme disease.
1995-1998 Vaccine found safe and
effective in people without Lyme disease.
1998 FDA approves Lyme vaccine.
2001 FDA withdraws Lyme vaccine from market.
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More than 100,000 cases of Lyme disease have been reported
in the United States, and the incidence is increasing each year. Approximately
12,500 new cases were diagnosed in 1997. Lyme disease can be difficult to
diagnose because it is easily mistaken for other ailments, and existing
laboratory tests can be inaccurate. Although Lyme disease can be treated
successfully in the early stages with antibiotics, patients who go untreated
or do not respond to antibiotics may develop significant complications months
or years later. These problems may include painful arthritis, especially
in the knees, nervous system difficulties, and heart complications. Treatment
of early-stage Lyme disease alone costs an estimated $60 million a year
in the United States.
Identification of an Emerging Disease
Lyme disease was first recognized in 1975, when researchers
investigated several cases of arthritis among children living in Lyme, Connecticut.
The researchers suspected that an unidentified infectious microbe caused
the illness, because the sick children lived near each other and became
ill at the same time. Many of the children also recalled being bitten by
a tick before becoming ill, and some developed a distinctive skin rash just
before other symptoms appeared. From these clues, the researchers suspected
that deer ticks, common arachnids the size of a pinhead, were involved in
transmitting an unknown infectious microbe.
Discovery of the Culprit
In 1981, as NIAID researchers were examining deer ticks
for microbes that cause tick-borne disease, the researchers serendipitously
found a new microbe. This spiral-shaped bacterium later was named Borrelia
burgdorferi, after the NIAID scientist, Dr. Willy Burgdorfer, who discovered
the microbe. The next year, NIAID researchers at the Rocky Mountain Laboratories
isolated B. burgdorferi from deer ticks and developed a method
to grow it in the laboratory. When scientists mixed the bacterium with blood
from people who had recovered from Lyme disease, they found that the microbes
reacted with a particular antibody produced during the immune response to
infection. Such antibodies were not present in people who had never had
Lyme disease, indicating that B. burgdorferi was the likely cause
of Lyme disease. In further tests, rabbits developed both a rash similar
to the typical Lyme disease rash as well as the same type of immune response
generated after being bitten by ticks infected with B. burgdorferi.
The following year, NIAID-supported scientists found B. burgdorferi
in the blood and other tissues of patients with Lyme disease.
In the mid-1980s, NIAID-supported and other researchers began to decipher
the makeup of the surface proteins of the microbe and made an important
discovery. They identified and analyzed a protein on the outer surface of
B. burgdorferi. This protein, outer surface protein A (OspA), causes
an immune response in humans. NIAID researchers then cloned the gene for
OspA and created recombinant OspA (rOspA). rOspA is an artificially manufactured
version of the natural OspA. This technique allows the protein to be produced
in large enough quantities for use in vaccine studies. In the early 1990s,
NIAID investigators and their collaborators found that antibodies against
OspA were able to neutralize B. burgdorferi in infected ticks,
thus preventing the transmission of infection from ticks to humans. As basic
research continued, other outer surface proteins as well as other parts
of B. burgdorferi were identified as potential candidate vaccines.
Development and Abrupt End of a Vaccine
Since these surface proteins produce an immune response,
researchers began to consider using them to develop vaccines against Lyme
disease. In the early 1990s, NIAID-supported researchers developed an OspA-based
vaccine that protected mice from infection.
Between 1995 and 1998, a vaccine based on rOspA, the component first made
by NIAID investigators, was tested by SmithKline Beecham in humans. The
vaccine was proven safe and effective for preventing infection for people
between the ages of 15 and 70. In 1998, the FDA approved a vaccine against
Lyme disease, LYMErix, produced by SmithKline Beecham. In 2001, the FDA
withdrew the vaccine from the market due to debilitating side effects.
Recommended Books:
Surviving Lyme Disease Using Alternative Medicine by David A. Jernigan
Outwitting Ticks : The Prevention and Treatment of Lyme Disease by Susan Carol Hauser
Everything You Need to Know About Lyme Disease and Other Tick-Borne Disorders by Karen Vanderhoof-Forschner
Source: Adapted from
the National Institute of Allergy and Infectious Diseases, National Institutes
of Health, Bethesda, MD 20892, January 2000 (updated April 2002).
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