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Testimony
on Hepatitis C by David Satcher, M.D., Ph.D.
U.S. Surgeon General
Assistant Secretary for Health
U.S. Department of Health and Human Services
Before
the House Committee on Government Reform and Oversight,
Subcommittee on Human Resources
March 5,1998
Good
morning. I am David Satcher, the Surgeon General of the United
States and the Assistant Secretary of Health in the U.S.
Department of Health and Human Services. I am here today to
discuss a major public health crisis: the hepatitis C
epidemic. Mr. Chairman, I know how much this issue concerns
you, and I commend you and your staff for your diligent
pursuit of it.
Hepatitis
C is a grave threat to our society. About 170 million people
around the world are infected, and at least 4 million of them
reside in the United States. About 85 percent of those
infected develop chronic liver disease, and about 10 to 20
percent eventually develop cirrhosis of the liver, about 20
years after the onset of their infection. Hepatitis C is the
most common cause of liver failure in patients who require
liver transplantation. Although the incidence of hepatitis C
in the United States has declined by over 80 percent since the
1980s, there are still about 30,000 new cases each year, and
each year about 10,000 people in this country still die of
hepatitis C. We conservatively estimate the total cost of
hepatitis C to our society at $600 million dollars per year.
The
estimate that there are 4 million infected individuals in the
United States is based on tests of blood samples obtained
during the CDC's Third National Health and Nutrition
Examination Survey (NHANES). This is a very extensive survey
that the CDC conducts on a representative sample of the entire
population of the United States. The fourth NHANES, scheduled
to begin later this year, will contain additional questions
about potential risk factors for hepatitis C, so that we can
gain a more precise estimate of how this disease is actually
transmitted in our society. The estimate that there are still
about 30,000 new cases of hepatitis C each year is obtained
from the Sentinel Counties Study of Viral Hepatitis, which the
CDC has been conducting since 1979.
We
know that many Americans infected with hepatitis C are unaware
they have the disease. unfortunately, many of them cannot be
readily identified, because the disease does not cause
symptoms until it is far advanced. However, there is one group
that can be identified: the roughly one million people who
have received blood from a donor who subsequently tested
positive for hepatitis C. In 1996, this Subcommittee formally
recommended that steps be taken to ensure that these
individuals be notified of their potential infection so that
they might seek diagnosis and treatment. On January 28,
Secretary Shalala announced just such a plan to notify people
who received blood from a potentially infected donor of their
risk. I will be in charge of implementing this plan.
In
accordance with the Secretary's directive, we will first
attempt to notify directly those at greatest risk. There are
roughly 300,000 people who have somewhere between a 40 to 70
percent risk of hepatitis C. They have this risk because they
received blood from a donor who later tested positive for
hepatitis C after June of 1992, when an accurate screening
test for hepatitis C was introduced. A Guidance to Industry
from the FDA which will announce the details of this lookback
will be published soon in the Federal Register.
However,
lookback will not reach everyone at risk, no matter how
diligent our efforts. For example, it will not reach the 20
percent of recipients whose donors never return to give blood,
and are therefore never discovered to have hepatitis C. At the
present time we do not feel that lookback would be an
effective means of reaching those who received blood from a
donor who was never tested directly for hepatitis C or who was
only screened with the first generation test, which missed
many who were truly infected and falsely identified even more
who were not infected. Finally, lookback will also not reach
the large majority of those who acquired hepatitis C from a
source other than blood. This is a particularly important
consideration now, because we have reduced the risk of
hepatitis C from blood transfusion to less than 1 per 100,000
transfusions, and we expect this risk to decrease further in
the future. The procedures for eliminating hepatitis C virus
from clotting factors were introduced over a decade ago.
For
all these reasons, lookback alone is not enough. I have
therefore directed the CDC to lead the second component of our
plan, which is to develop educational programs for health care
professionals and the public at large to support recognition,
diagnosis, counseling, and testing of those at risk for
hepatitis.
The
third component of our plan is to evaluate carefully the
success of both our direct and general notification efforts,
and take additional steps to address unmet needs as we
identify them. We have proposed an aggressive time table for
implementing these programs, and we will actively monitor
their progress at the highest level of the Department through
the Public Health Service Blood Safety Committee, which I
chair.
Secretary
Shalala has made the Department's policy in this matter very
clear. As she said on January 28 of this year....... these
steps are only the first phase of a comprehensive plan to
address this significant public health problem. It is my
intention to reach effectively as many people at risk as we
can." I want to underscore these words. Everyone we
believe to be at risk of having hepatitis C will be targeted
by the Department's plan.
As
part of the Department's efforts to educate the public about
risk of hepatitis, we must be aggressive about discussing
prevention. Hepatitis C is transmitted by blood. Hemodialysis
patients are at high risk of hepatitis C infection, as are
those who have used injection drugs, even if only occasionally
and only in the distant past. Perinatal transmission occurs,
though much less efficiently than transmission of hepatitis B
or HIV. Sexual transmission within monogamous relationships
appears rare, but there may be greater risks for those with
multiple partners. The risk from transfusion is now very
small, less than 1 per 100,000 transfusions, and we will take
advantage of every opportunity available to reduce this risk
even further.
There
is no cure for hepatitis C. However, treatment is improving.
Recent experience with interferon alpha treatment indicates
that more prolonged therapy, and the combination of interferon
alpha with ribavirin, may provide substantial additional
benefit to certain patients. Although these new treatments
show promise, much better ones are needed. I am cautiously
encouraged by the commitment of the pharmaceutical industry to
the development of protease and helicase inhibitors of the
hepatitis C virus.
What
we really need, of course, is a vaccine against this disease.
There are vaccines against hepatitis A and hepatitis B, and
there is ongoing work on a vaccine against hepatitis C.
However, we cannot underestimate the complexity of this task,
particularly because of the rapid rate at which the virus
mutates, and we must nurture the basic and clinical research
that will be necessary to support vaccine development.
Research
is the foundation of our struggle against hepatitis C. As you
know, the hepatitis A and hepatitis B viruses were discovered
at the NIH. Dr. Baruch Blumberg, the discoverer of hepatitis
B, received the Nobel Prize for his work. This work led to the
appreciation that there was at least one more hepatitis virus
to be found. The major one of these, hepatitis C, was
identified in 1989.
The
discovery of the hepatitis C virus permitted the development
of progressively more sensitive tests for the presence of
hepatitis C in human blood. The first blood donor screening
test was licensed in May 1990, only a yeer after the virus was
identified. This test measured antibody to a single hepatitis
C antigen. This test identified nearly 90 percent of patients
with transfusion- associated non-A, non-B hepatitis. However,
this test had limitations, notably a 24 week window period
between the time a subject was infected with hepatitis C and
the time the test could detect antibodies to hepatitis C in
the subject's blood.
The
more effective blood donor screening test was introduced in
June of 1992. This "second generation" test measured
antibodies to three different hepatitis C antigens, and it
reduced the window between infection and detection from 24 to
12 weeks. The date at which this test was introduced is the
point in time around which our lookback and public education
efforts revolve.
Direct
funding for research on hepatitis C among all the institutes
at NIH will increase from $25.3 million in 1997 to $29.8
million in 1998 and $34.4 million in 1999. A steering
committee has recently been formed to provide more focused
oversight of the hepatitis C research effort. The dollar
amounts for NIH-sponsored hepatitis C virus research do not,
of course include funds spent on epidemiologic research by the
CDC and funds spent on both basic and applied research by the
FDA.
The
NIH intramural program is focused on virologic, immunologic,
and clinical studies which will support therapeutic and
vaccine development, as well as the advancement of basic
scientific knowledge. Dr. Stephen Feinstone of the FDA's
Center for Biologics Research and Review, who was a member of
the team that discovered hepatitis A, recently reported the
construction of an infectious clone of the hepatitis C virus,
an important step towards the eventual development of a
vaccine. Extramural programs include four newly established
Hepatitis C Cooperative Research Centers, which among their
other works conduct studies of the natural history of
hepatitis C in African Americans, Native Alaskans, and
children. Studies of the natural history of hepatitis C after
liver transplantation are also under way.
Let
me conclude by reemphasizing that the U.S. Department of
Health and Human Services joins in your concern regarding the
impact of hepatitis C on our nation's health. I want to thank
you for this opportunity to describe our efforts to control
and, ultimately, eradicate this terrible disease. I would be
delighted to answer any questions the Committee may have.
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