In the News
As published in the New Haven Register, July 5, 2006.
Ticks Carry More Than Lyme Disease
By Ti Badri
The first study of its kind in Southern
Connecticut has revealed that ticks may
carry up to half a dozen disease-causing
micro-organisms, which could explain why
some people with Lyme disease continue
to suffer mysterious symptoms for
decades despite long-term treatment.Researchers at the University of New
Haven are also developing a new type of
test to reveal these previously
unrecognized organisms, which may
complicate diagnosis and treatment of
Lyme disease.
The new test is designed to avoid the
protracted nightmare that Julie Hunter,
20, has suffered since she contracted
Lyme disease in 1999.
Physicians quickly diagnosed the
bacterium that causes Lyme disease, but
missed a more elusive germ that the tick
also injected into her bloodstream.
"Present test results are unreliable and
doctors stop as soon as the test comes
out negative," said Hunter’s father,
David Hunter of Southbury.
He said that if the UNH test works, "It
would greatly help the patient
community. Julie had a co-infection that
interfered with her Lyme disease
treatment."
Many people with lingering symptoms of
Lyme disease may actually be infected
with one or more previously unrecognized
bacteria, viruses, parasites and
protozoa, said Eva Sapi, assistant
professor of molecular biology at UNH
and senior author of the study, which is
being prepared for publication.
Doctors, infectious disease specialists
and Lyme disease experts said the
problems posed by stowaway pathogens are
significant. However, some scientists
said the new test could be impractical,
expensive and prone to poor quality
control.
Current Lyme disease tests depend on
antibodies produced by the patient in
response to the invading spirochete. The
test being developed by UNH’s molecular
biology department is intended to work
by identifying specific fragments of
foreign DNA generated by the infectious
organisms.
The Lyme disease project will shed light
on the types and frequencies of
tick-borne microorganisms in southern
Connecticut, Sapi said.
Researchers hope the new test kits will
provide a quick and reliable method of
diagnosing tick-borne diseases, enabling
doctors to better treat patients
suspected of having Lyme disease.
"Lyme patients will finally know what’s
going on. They will finally have
closure," Sapi said.
Experts see the potential benefits of
the new test, but question its
practicality. The test is based on
polymerase chain reaction, a standard
method of "amplying," or making
countless copies of a piece of DNA.
"PCR is doable in ticks, but researchers
have to keep track of emerging
infections," said Stephen Wikel,
professor of immunology at the
University of Connecticut Health Center.
"The test is feasible using real-time
PCR", said Connecticut’s chief
entomologist, Kirby Stafford III.
Real-time PCR can detect specific DNA
sequences as they happen in the reaction
chamber, allowing researchers to keep
track of quantities of reacting
materials at every stage of the process.
Other doctors aren’t so sure.
"Individual tests using PCR are quite
expensive and depend on quality
control", said Dr. John Shanley,
infectious diseases specialist at the
UConn Health Center.
Prior to the study carried out at UNH,
there were no in-depth studies carried
out in Southern Connecticut to determine
what kind of microorganisms ticks have
and what co-infections are present, Sapi
said.
These tick-transported pathogens include
Bartonella, Mycoplasma and the virus
that causes Colorado tick fever.
Bartonella causes cat scratch disease,
and Mycoplasma is a bacteria-like
organism associated with respiratory
illness.
Researchers found that some ticks
collected around Bridgeport and Hamden
over the course of a year were infected
with up to six different microorganisms.
"We always believed only one bacteria
was present in the ticks, now we know
that there are co-infections," Sapi
said.
Multiple infections are very difficult
to properly diagnose and treat, she
said. Patients with multiple infections
have significantly more complicated
symptoms and poorer outcomes because
different infections require different
treatments, Sapi said.
For example, antibiotics cannot be used
if a patient is found to have a viral
co-infection; anti-viral drugs must be
used instead. If left untreated, the
corkscrew-shaped Lyme disease spirochete
can cause fever, arthritis, swollen
lymph nodes, aches and pains, and
sometimes, a bull’s-eye rash. However,
not all patients will have all the
associated symptoms.
Whatever scientists can do to ameliorate
the anguish of Lyme disease should be
pursued, including new tests, said David
Hunter.
"I think it would be huge for the
patient community because many people
remain largely ignorant of the impact of
the disease," he said. |