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<text id=89TT1118>
<title>
May 01, 1989: Coming Soon--Safer Blood
</title>
<history>
TIME--The Weekly Newsmagazine--1989
May 01, 1989 Abortion
</history>
<article>
<source>Time Magazine</source>
<hdr>
MEDICINE, Page 66
Coming Soon: Safer Blood
</hdr><body>
<p>A new test can detect an elusive and dangerous hepatitis virus
</p>
<p> Many people who get blood transfusions these days are
understandably nervous. Transfusions have saved countless
lives, but they have sometimes transmitted serious blood-borne
diseases, including AIDS. While public health officials point
out that careful testing has all but eradicated the AIDS virus
from the blood supply, they have not been able to claim that
transfusions are perfectly safe. Reason: about 5% of patients
who receive transfusions are exposed to a virus that can cause
a potentially deadly liver infection called non-A, non-B
hepatitis.
</p>
<p> The mysterious malady is so named because it is not caused
by the widely recognized A and B strains of hepatitis viruses.
Symptoms include fever, nausea and fatigue and, in chronic
cases, cirrhosis of the liver. About 5% of the U.S. population
harbors non-A, non-B viruses. The majority of those who are
exposed show no symptoms, but of the patients who come down with
chronic liver disease, an estimated 10% die within five years.
About 150,000 new infections occur each year because of blood
transfusions.
</p>
<p> This last major threat in the U.S. blood supply may soon be
greatly reduced. After six years of research, scientists at
Chiron, a genetic-engineering firm in Emeryville, Calif., have
developed a test for the presence of a non-A, non-B hepatitis
virus in blood samples. According to papers published last week
in the journal Science, trials have shown that Chiron's test is
highly reliable. It can now help eliminate the virus from the
blood supply. The inexpensive test (about $2 per blood sample)
is expected to be approved by the Food and Drug Administration
this year and marketed early in 1990 by Chiron and Ortho
Diagnostics Systems, a subsidiary of Johnson & Johnson. Said Dr.
S. Gerald Sandler, medical director for blood services of the
American Red Cross: "This is a very significant scientific
achievement that virtually closes the chapter on
post-transfusion hepatitis."
</p>
<p> Chiron's initial breakthrough was to isolate a viral
protein from blood samples taken from patients with non-A, non-B
hepatitis. By cloning large quantities of the protein, the
company was able to develop a test to detect its presence in
blood. Chiron called the pathogen the "hepatitis-C virus." In
clinical studies done at the National Institutes of Health, the
Centers for Disease Control and laboratories in Italy and Japan,
blood samples from patients thought to have non-A, non-B
hepatitis were screened using Chiron's test. At least 80% of the
samples tested positive for the hepatitis-C virus.
</p>
<p> The fact that the test did not detect non-A, non-B
hepatitis 100% of the time suggests that there may be still more
viruses at large that can cause hepatitis. But the A, B and C
viruses seem to cause the large majority of cases, and so
researchers are confident that they can now almost eliminate the
risk of contracting hepatitis from a blood transfusion.
</p>
<p> Eradicating the disease is another matter. Like the AIDS
and hepatitis-B viruses, hepatitis C is spread by sexual contact
and, among drug addicts, through contaminated needles. But
Chiron's work offers hope that the disease can be controlled.
Isolating a protein from the hepatitis-C virus has made it
possible to develop a vaccine to ward off the infection. Chiron
biochemist Michael Houghton cautions that hepatitis C could be
"one of those awkward viruses like herpes and AIDS" for which
vaccines are elusive. But, he says, the C virus resembles the
one that causes German measles, which can be prevented by one
of the "best vaccines ever developed." Chiron plans to test
potential hepatitis-C vaccines in animals later this year.
</p>
</body></article>
</text>