The Michigan Daily - Friday, January 27, 1995 -3
Detection
methods
help control
spread of
deadly virus
Stories By Kelly Feeney
Daily Staff Reporter
The HIV-antibody test is the one test that
can be called the ultimate "killer."
Uncontested in the fear, anxiety and stress
it causes, the test's eventuality cannot be
avoided.
Living in the age of AIDS, the reality is
that someone we know - and perhaps our-
selves included - will someday have to be
tested for this deadly virus.
The HIV-antibody test, commonly referred
to as the AIDS test, is a blood test that detects
HIV antibodies produced when the body has
been infected with the Human Immuno-defi-
ciency Virus (HIV).
Because HIV is the virus that can develop
into AIDS (Acquired Immuno Deficiency
Syndrome) the results - either HIV-positive
or HIV-negative - can have profound affects
on a person's future.
In 1992, 2.7 million HIV-antibody tests
were administered at public clinics in the
United States. Since the test was approved in
1985, the number of tests has annually in-
creased and has entered the mainstream of
health concerns.
At University Health Services (UHS) in
1993, 1,049 people were tested for the virus
- with 75 to 80 percent of the tested persons
being students.
The HIV-antibody test is important not
only because it detects the presence of HIV -
which, if detected early, can stop the threat of
AIDS developing - but also because of the
preventative measures the test takes.
As part of the testing process, patients
receive counseling on HIV risk factors, how
HIV is spread and safer sex guidelines. Stud-
ies have shown this counseling increases a
patient's knowledge of HIV transmission,
which can decrease the transmission of the
virus and other sexually transmitted diseases.
For college students, whose sexual prac-
tices are often "risky" - having multiple sex
partners and not practicing safe sex - the
HIV test takes on special importance. It not
only helps to educate, but it serves the imme-
diate need of allaying the fear of possibly
being infected.
The idea of being tested for a virus that can
cause death doesn't sit well with many stu-
dents-mortality and youth have never mixed.
Yet understanding how the HIV-antibody test
works is crucial. As the number of AIDS
rcases increases and a vaccine is still to be
found, knowing who carries the virus is the
only way to curb its spread.
Students and Testing
at the "U"
Since 1987, University Health Services has
provided free HIV-antibody testing and coun-
seling to students. Conducted anonymously or
confidentially, the test from the initial blood
work to lab analysis takes two week.
"Most of the students we test are average
college students, who have a sophisticated
knowledge as to how AIDS is transmitted,"
said Jen Stewart, a health promotions officer
who oversees testing and counseling at UHS.
Stewart indicated that students know how
Detecting a Debilitating Disease
Two tests for detecting HIV, the virus that causes AIDS, have become the first steps in recognizing the disease.
Both tests work off the theory that when HIV enters a person's body, the immune system immediately responds
by forming antibodies. Here's how they use the information.
The ELISA test
The enzyme-linked immunosorbent assay test detects the presence of HIV-1
collectively labeled HIV, in the patient's blood serum.
Actual HIV
antigens are
produced in
laboratories
and used
to coat the
inside of a
test tube.
v'~'
/'
Blood serum from the
patient is added to the
test tube. If HIV
antibodies are present,
they will bond to the
antigens.
t
and HIV-2 antibodies,
An anti-human
antibody, which is
labeled with an
enzyme, is injected
into the test tube
and will bond
with the HIV
antibodies.
6 u4
lust a Review
Here are some of the
important terms when
talking about AIDS.
AIDS - Acquired Immune
Deficiency Syndrome. It
attacks the body's -
immune system, making
it impossible to fight off
even the simplest
infections.
HIV - Human
Immunodeficiency Virus,
the disease that causes
AIDS. It is spread through
bodily fluids and cannot
survive outside the body
for any extended period
of time.
Antigen - Produced by
the body to fight a virus.
Appear early, but are
expensive to detect.
Antibody - Work through
antigens to kill a virus.
Develop later, but are
much easier to find in
chemical tests.
Where to get
tested
University Health
Services, 207 Fletcher
St., Ann Arbor. 763-
1320.
Planned Parenthood,
3100 Professional Dr.,
Ann Arbor. 973-0155.
Washtenaw County
Health Dept., 555
Towner, Ypsilanti,
484-6760.
AIDS Hotline, 1-800-
342-AIDS(24 hour).
CDC AIDS Hotline, 1-
800-342-2437.
A substrate, which "locks" to the enzyme, is added to the serum specimen and causes the solution to change
color. By measuring this color change, doctors can detect the HIV antibodies.
The Western Blot test
This test, used to confirm a positive ELISA test result, also relies on a color change.
Electric current is passed through the sample, which causes the HIV antigen fragments to separate
with the larger, darker bands to float to the top of the sample. The distance travelled by the dark
band determines if the sample contains HIV antigens.
False Positives
While these tests have become more accurate over the last few years, they are still only about 99 percent effective, meaning that 1 of every 100
tests will come back incorrect, possibly resulting in a positive test for someone who is HIV negative. Much rarer is a negative for someone who
is HIV positive. False readings may also occur if the test is performed less than six months after possible exposure. Doctors strongly
recommend anyone who tests positive seek medical evaluations.
JONATHAN BERNDT/Daily
to have safe sex, but "putting it into practice" is
where they have difficulty.
Consequently, students get tested because
they have doubts and concerns that they may be
infected.
Many students UHS tests indicate they've
had unprotected sex once or sex while under the
influence of alcohol. Some have had unpro-
tected sex numerous times. Some couples get
tested together before beginning a sexual rela-
tionship.
Before any blood is drawn and analyzed,
students are required by
state law to receive
counseling. UHS offers m ost
both a half- hour pri-
vate and an hour-long averag e,,
group session. In each
session, students and sophisic
counselors discuss -i
ways to reduce risk fac-
tors of becoming in-
fected, safer sex meth-
ods and any other con-
cerns or questions the
student has.
Ninety-five percent of students are tested
anonymously. No personal information is re-
quired of the student who chooses to be tested
anonymously, and no written record of the test
is kept. Test results are obtained by the student
using a number as identification. If the student
needs written confirmation of the test, usually
for employment purposes, a confidential test in
which the results are only released to the stu-
dent and kept in his/her's medical chart is
administered.
One LSA student, who was being tested
anonymously, expressed anxiety at not know-
ing whether she was HIV-positive. She decided
to take the test to confront reality and her fears.
"Knowing that I'm being ignorant is what's
making me get tested," said the student, who
had unprotected sex.
One night, about six months ago, after hav-
ing unprotected sex in a monogamous relation-
ship, the student sat up all night "checking my
calendar so that I could mark the date, six
months later, when I could be tested," she said.
She realized that she had to face reality her
partner's previous sexual relationships may
have infected him, and then her, unknowingly.
The reality that she might have HIV was too
overwhelming and stupid not to confront, she
said.
UHS tests results mirror the national aver-
age - about two in every 1,000 people test
positively.
Even though nearly all tests result nega-
tively - only 49 HIV-positive cases have
been reported to UHS during the past eight
years - the actual number of HIV cases may
of the students we test
college students who ht
ated knowledge as to h
fitted. "
UHS Hf
be higher, and increasing, but the people who
have it may not be getting tested.
And though a 1990 report issued on the
prevalence of HIV among college students
found the rate of infection to be only 0.2
percent, no one knows for certain the magni-
tude of the virus' threat.
"We can know the number of tests admin-
istered and the results, but we don't know the
prevalence in the population," Stewart said.
Though she said that not knowing the preva-
lence in the population is "the crux of testing,"
she said the test can help people to learn their
status and more importantly can educate them.
"But the important thing is to give people
the opportunity to learn. The key to prevent-
ing HIV is education," she said.
The Test and Results
The HIV-antibody blood testis not an AIDS
test - and the result, if it is positive, is not a
diagnosis for AIDS. The test only detects HIV
antibodies.
Clinical procedure of the test involves
drawing a small blood sample from the patient,
upon which two different tests are conducted.
The ELISA (Enzyme-Linked
Immunosorbent Assay) is the first test run on
the blood sample. As a sensitive screening
test, ELISA tests blood serum for HIV-I and
HIV-2 antibodies.
If antibodies are detected, the test is re-
peated a second time on a different blood
sample. If the second examination indicates
that antibodies are present, there is a high
probability that the person has been infected
with HIV. But a sec-
ond test is needed to
are confirm the ELISA
result.
ave a The Western
Blot test is the con-
ow AIDS firming factor in de-
tecting the presence
of HIV-antibodies in
- Jen Stewart the blood serum. It
not only detects the
V-testing officer presence of antibod-
ies mounting, but it
also gives insight into
what antigens the body has produced in re-
sponse to the virus entering the body.
A positive Western Blot result confirms
that the body has been infected with HIV and
is producing an antibody reaction. A negative
results mean antibodies are not present.
Because the Western Blot test is the more
conclusive of the two tests, a negative West-
ern Blot result can negate an ELISA positive
result. Though rare, an initial indication of
HIV-antibodies reported with the ELISA test
can turn out to be false.
In the beginning days of HIV testing the
discrepancy between the two test results was
greater. Today, the two tests give correct
result 99.8 percent of the time.
At UHS, Stewart said if a person tests
positively, another test is conducted to con-
firm the results, and partners can be notified
anonymously to learn if they are infected.
Yet, patients should beware of a negative
test result - they are not yet clear from risk.
Research indicates that a majority of people
will begin developing antibodies within three
months after infection - yet it can take up to
six months for antibodies to appear.
If a person is tested during the "window
period" - a time too early to begin detecting
antibodies - he or she may mistakenly think
the virus has not infected the body when'it
may have.
"During that window period, people think
that they're home free, but that might not be
true," said Barry England, director of the
Ligand Assay Laboratory at University Hqs-
pitals. "You may be infectious and infect
someone else when you think that you're safe.
"Most people don't get tested until they
think they may have been exposed and in-
fected," England said. But, he warned, "If you
get exposed, that's it.
"The implications are that you have to be
extremely careful all the time. What's so
terrible about the disease is that in the early
stages there are no symptoms," England said.
Also during the early stages, particularly
during the primary two months, a person is
most infectious, according to a study released
by a team of University researchers earlier
this month.
If a person engages in sexual activity, it is
important to realize the risk and plan to get
tested. If not, according to the study, the
person has a higher chance of spreading the
virus to more people if risky behavior contin-
ues.
"The most dangerous person is not
seropositive. The most dangerous person is
seronegative who is having outside relation-
ships," said James Koopman, a professor of
epidemiology and one of the three University
researchers who completed the study.
Until a cure is found ...
AIDS may well in fact prove to be the curse
of generations to come - and its presence
today seems to affect more and more people's
lives.
With a cure and vaccine still still to be
found, the only way to stop the spread AIDS
is through prevention.
The HIV-antibody test doesn't have to-be
a "killer" - but can be if people don't learn
the lessons of prevention.
AIDS Stats
'U' students trained in AIDS risk assessment
Number of tests administered at public clinics (1992): 2.7 million
Approximate number of people with HIV:1 million
Number of AIDS cases reported to the Center for Disease
Control (June 30, 1994): 401,749
Number of cases, ages 13-19: 1,768
Number of cases, ages 20-24: 15,204
Number of cases, ages 25-29: 60,042
Total AIDS related deaths: 243,23
Talking about sex with a stranger
makes many people feel uncomfort-
able- even when that stranger is a
doctor. Because of the uneasiness
and tension felt by both patient and
doctor toward the subject, the sexual
history examination is one of the
most uncomfortable aspects of as-
sessing AIDS risk.
Sometimes thought of as "uncar-
ing" and "cold" in their medical pro-
cedure, doctors face even more scru-
tiny when examining a patient's
the medical students to hone their
communication skills.
The program, titled "Introduc-
tion to the Patient," runs throughout
the four years of medical school.
The second year emphasizes taking
patient sexual histories and making
AIDS risk assesment.
"It's well known that it is diffi-
cult to broach this kind-of subject,"
said Dr. Andrew Zweifler, one of
the program's coordinators, adding
that students must be able to over-
take in their own lives to decrease
the risk of infecting, or becoming
infected, with HIV and other sexu-
ally transmitted diseases.
A simulated sexual history inter-
view with "patient instructors" - who
are usually other University students
- allows the medical students to prac-
tice different techniques.
During the interview, doctors
must ask the "patient" questions
about his orher sexual history, which
has been created for them.
and understand the problems the
patients are facing. AIDS risk aware-
ness is also very important on the
patient-instructors' eyes.
Lisa Lowery, a medical student
in the program, agreed.
"You have to remember that there
is a person behind the patient," she
said. For her, the interview is stress-
ful, but it provides a great opportu-
nity to practice the skills she and her
classmates are going to need in the
future.
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