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Blood Safety Summary - August 1997
Advisory Committee on Blood Safety and Availability
Summary of Meeting
Second Meeting August 11-12, 1997
The Chairman called the meeting to order at 9:00 AM. Members present were Dr.
Caplan, Dr. Albrecht, Mr. Allen, Dr. AuBouchon, Dr. Busch, Dr. Gilcher, Dr.
Gomperts, Dr. Guerra, Dr. Haas, Dr. Hoots, Ms Jones, Dr. Kuhn, Ms. OConnor,
Dr. Penner, and Mr. Walsh. Ex Officio representatives present were Dr. Goosby,
Dr. McCurdy, Dr. Chamberland, Dr. Snyder, and Captain Rutherford; Dr. Wycoff
attended in place of Ms. Pendergast.
Dr. Eric Goosby, on behalf of Dr. John Eisenberg, the Principal Deputy Assistant
Secretary of Health, welcomed the participants and introduced the newly appointed
Executive Secretary of the Committee, Dr. Stephen Nightingale.
Mr. Jim McPherson, representing Americas Blood Centers, was the first person
to address the Committee. Mr. "...
donor lookback will not identify" the majority of patients who have
[been] infected ...; nevertheless,
it is difficult to argue that blood centers in possession of information about
a recently acquired infectious state of a donor should not perform lookback
for HCV as they already do for HIV and HTLV." Mr. McPherson requested that
a limit be placed on the time of any prospective lookback program, that the
government provide funding for any prospective lookback program, and that
provider and patient educational initiatives be considered in lieu of a retrospective
lookback program.
Ms. Fay Lamb, representing the Cooleys Anemia Foundation, requested the Committee
support a lookback system which would notify~" patients "...
that there is a reasonable probability that they have received tainted
blood" and that adequate counseling be provided to those so notified.
Dr. Paul Mied of FDA then summarized FDA policies regarding product retrieval
and recipient notification in transfusion lookback programs for HIV, HBV,
HCV, and HTLV-I. Current policy, established in June
1996, is that product quarantine and recipient notification are recommended
for HIV; for the others, only product quarantine is
recommended. Dr. Mied noted that in June 1993, after introduction of the second-generation
antibody and the REBA-2 confirmatory tests for HCV, the FDA Blood Products
Advisory Committee (BPAC) had recommended consignee notification for purposes
of recipient notification of possible HCV exposure by a vote of 5 to 4, but
that BPAC had expressed reservations about the benefit of this activity.
Dr. Harold Margolis of CDC reviewed the PHS Plan for the Prevention and Control
of Hepatitis C. Dr. Margolis emphasized the need for education of both providers
and the public. He mentioned the March 1997 NIH Consensus Conference on HCV
the planned November 1997 CDC teleconference on this subject, and the contributions
of non-governmental organizations to the educational effort. Dr. Margolis
also expressed concern over the high prevalence of HCV infection in prison
populations and the difficulties in providing HCV testing to medically indigent
populations. In response to questions, Dr. Margolis noted that about 3.9 million
Americans (about 2%) are thought to be infected with HCV, about 8,000 to 12,000
deaths each year in the United States are attributable to HCV, that the incidence
of HCV has decreased by about 90% since 1990.
After a recess, Dr. James AuBouchon presented a cost-effectiveness analysis
of HCV Iookback. Using American Red Cross data, he estimated that between
1990 and 1995 88
% of donors were repeat donors, that there were approximately 91,000
donors who were identified as HCV-infected at a repeat donation, and that
about 5 blood
components would have been derived from each donor between 1985 and the time
the donor was found to be HCV-infected. He estimated that approximately 60
% of the 450,000 potential recipients of these potentially infectious components
would be dead, that only 33 % of the survivors would be traceable, that 40
% of those traceable would not be infected either because the HCV test of
the donor was a false positive or because the recipient was either never infected
or spontaneously recovered, that 70 % of those found to be truly positive
would be candidates for therapy, and that 15 % of these would benefit from
therapy. Dr. AuBouchon estimated it would cost $137 to identify~" each donor
or $27 per component, and that the age of the average recipient would be 60.
Dr. AuBouchon found that, in his model, the cost-effectiveness of lookback
was most sensitive to the benefit he assigned to interferon therapy, to how
recent the transfusion was, and to the age of the patient. He felt that the
average cost-effectiveness of lookback in his model ($88,000 per year of life
extended) was comparable to other therapies; however, he concluded that only
I per hundred in the original pool of 450,000 recipients would benefit from
a Iookback.
Ms. Lisa Ungerer then addressed legal issues surrounding lookback, focusing
on "avoidable lawsuits". She recommended a standard and easily understandable
notification format, and cautioned that ad hoc approaches to notification
might increase exposure to litigation.
Dr. Ronald Gilcher then discussed differences in Iookbacks for the periods
prel99O, 1990-present, and present onward to the future. He acknowledged that
his analysis was very similar to that previously presented by Drs. Margolis
and AuBouchon.
Dr. Harold Kaplan followed with a discussion of the impact of lookback on
hospital transfusion services. He estimated that for a hospital with a computerized
transfusion record system, about 90 minutes work time would be required per
notification attempt. At his 1000 bed hospital he estimated about 1500 notifications,
which would consume the efforts of 1.3 full-time-equivalent workers for one
year. Dr. Kaplan noted the impact of such a lookback would be ameliorated
if it could be spread over one year.
After a lunch break, Dr. Stuart Gordon and Dr. Leonard Seeff described clinical
aspects of hepatitis C infection in their practices. Dr. Gordon studied 627
consecutive patients with HCV infection. He found more severe disease in older
patients, and in patients who had acquired HCV by transfusion rather than
by intravenous drug use. In Dr. Seeff's own cohort of 568 cases, 53% of patients
have persistently elevated liver enzymes at 15 to 18 years after infection;
10 % no longer have antibody, and 28% no longer have PCR-detectable antigen
at this point. In contrast, 13 % have symptomatic liver disease, and I % have
developed hepatoma.
Dr. Angela Robinson then described the British experience with HCV Iookback.
She noted the differences between the British and American health care systems,
and the fact that Britain began HCV screening with the second generation HCV
test with REBA confirmation. The decision to perform a lookback was made in
1994 on the basis of "duty of care". In Britain, with a population of about
50,000,000, about 3,000 HCV-infected donors and about 12,000 blood components
from these donors were identified. About 6,000 recipients were identified,
of which 4,000 had died; 75 % of the survivors were located. At present 581
of these are HCV positive, 369 HCV negative, 75 indeterminate. Twenty of the
581 HCV positive patients have symptomatic liver disease.
Dr. Peter Gill then described the Canadian experience with HCV Iookback.
Canada also initiated a HCV lookback program in 1994. A provider and public
education program was implemented, including brochures and toll-free hotlines
for providers and public. Canada introduced the first generation HCV test
at the same time (March 1990) as the United States, and the second generation
test in 1991. The yield of lookback was very similar to the British yield.
The day concluded with a general discussion of the issue of HCV Iookback.
At the conclusion of this discussion, the minutes of the previous meeting
were approved unanimously. The meeting recessed at 5:32 PM.
Dr. Caplan called the Committee to order at 8:00 AM on August 12. Dr. Michael
Busch discussed the risks of transfusion, and how they had decreased in recent
years. At present, he stated that potential failure to interdict infection
can be due to preseroconversion windows, viral variants, silent carriers (non-seroconverters),
and technical error. For HCV, the pre-seroconversion window is roughly 80
days from exposure to seroconversion, and viremia occurs during this period.
HCV viral variants are very rare. Silent carriers occur in about 1:10,000
HCV infections. Dr. Busch estimated test error at a rate of 0.067%; however,
this error must occur in processing a contaminated specimen for it to be clinically
significant, and the combined probability of these events is small. The cumulative
risk at present fro HCV transmission by any of these mechanisms is now about
1 in 5000, and for any of HIV, HBV, HCV, or HTLV-I it is about 4 in 10,000.
Mr. Edward Maibach of Porter Novelli then gave a presentation about dealing
with and communicating risk. He enumerated several cognitive strategies humans
use to process concepts of risk and uncertainty, for example the tendency
to overestimate the frequency of rare events, and he made several suggestions
for communicating information about risk, for example use of language appropriate
for the target audience.
The remainder of the meeting was taken up with formulation of specific recommendations.
The discussion began with a draft proposal of Dr. Hoots; numerous modifications
were proposed. After a luncheon recess, Dr. Busch suggested a modification
of Dr. Hoots proposal. After further discussion, the Busch modification of
the Hoots proposal was approved by a vote of 13 to 0, with Dr. Penner abstaining
and Dr. Caplan, the Chair, not voting. The approval was with the understanding
that the proposal would be edited for grammar and clarity, with modifications
submitted to the Committee members for their approval. The final text of this
Resolution is amended to these minutes.
Following the vote, Dr. Penner stated that he agreed with what the Committee
had done so far, but felt it had not gone enough because it did not support
lookback for first generation-positive donations. Dr. Penner stated he hoped
the Committee would return to this issue at a future time. Dr. Caplan stated
that he would consider Dr. Penners request, and that he leaned in the direction
that Dr. Penner was articulating.
The meeting was adjourned at 3:00 PM.
respectfully submitted,
Stephen D. Nightingale, MD
Executive Secretary
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