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The Smallpox Vaccination Plan: Challenges and Next
Steps
Bill Number: Oversight Hearing
Hearing Date: January 30, 2003
Witness:
William J. Bicknell, MD, MPH
Boston University School of Public Health
Boston, MA
Testimony:
Mr. Chairman, members of the committee, colleagues
and guests, it is an honor to be invited to testify
before the Health, Education, Labor and Pensions Committee.
My name is William J. Bicknell, I am a physician with
a public health degree, have served as Commissioner
of Public Health in Massachusetts, am Board Certified
in Public Health and Preventive Medicine and have
been a Professor of Public Health and International
Health at Boston University's Schools of Public Health
and Medicine for over 20 years. Most recently I have
been a proponent of careful, selective, progressive
and, ultimately, widespread, pre-exposure vaccination
as the best way to protect the nation against the
threat of a bioterrorist attack using smallpox as
a weapon.
Issues of national security, economics and economic
disruption, medicine, public health, and labor/management
issues often get confused as we discuss smallpox.
This is complicated by misunderstanding of the facts,
confusion of fact and opinion and, finally, honest
disagreements as to the correct course of action.
And, as we consider smallpox, it is important to remember
that it is just one of a number of bioterrorist threats.
CONTEXT
First let me provide some context. Smallpox (Variola)
is very contagious with a 30% overall fatality rate
in persons who have not been vaccinated. 60% to 80%
of survivors are disfigured. There is no treatment.
It is a terrible disease and an excellent weapon.
The threat is widely believed to be real but cannot
be quantified. However, as the consequences of a terrorist
release of smallpox on an unprepared nation have the
potential to be devastating, preparation is essential.
Many of us were vaccinated years ago. This decreases
the likelihood of vaccine complications and may provide
some very limited immunity to smallpox. From a personal
or public health perspective the only significant
benefit of vaccination 10 or more years ago is a further
reduction in the already low rate of vaccine complications
in adults. More about this shortly. The important
point is anyone who has been vaccinated over 10 years
ago cannot count on being protected from smallpox.
The nation is far better prepared today for a smallpox
attack than it was even a few months ago. The three
phase plan announced by the President in December
is prudent and makes excellent sense. A tremendous
amount has been accomplished and Drs. Fauci and Gerberding
deserve to be congratulated for their leadership and
excellent work. We now have sufficient vaccine to
protect everyone and Vaccinia Immune Globulin (VIG)
to treat the treatable complications of vaccination.
The President’s policy, as announced in December,
if it is fully and well implemented and if we move
rapidly with no discernable pause from Phase I to
Phase II, will give us the ability to rapidly control
a terrorist generated outbreak of smallpox. But we
are not yet ready. Before addressing the remaining
issues and problems, I would like to summarize some
facts about smallpox vaccination.
VACCINATION – SOME FACTS
Smallpox was eradicated in the 1970s after many years
of great effort. At that time the immunity level of
the general population was very high and most people
in Africa and Asia were far less mobile than our population
today. Today’s American population is substantially
non-immune and highly mobile. No one has any experience
in dealing with an outbreak of smallpox in this very
different and dangerous context. The unquantifiable
but real risk of attack and our highly mobile and
substantially non-immune population requires us to
plan for a worst-case scenario, not a desirable or
not too bad scenario. Managing less is easier. However,
terrorists can do their job well. We know this. Planning
for less than a worst case could be disastrous.
As we consider the possibility of attack, we must
think beyond the tragedy of deaths and disfigurement
and recognize the consequences of substantially shutting
down commercial activity for weeks or more. In addition
to domestic disruption, it would be reasonable for
other countries to ban all arrivals from and departures
to the United States. If panic, civil unrest and martial
law were to ensue, the adverse consequences to the
United States will be immense, horrible and incalculable.
My most fundamental message to the Committee is we
must rapidly complete Phase I and, without pause and
with contemporaneous evaluation of Phase I results,
move rapidly and without delay into Phase II of the
President’s plan. In my judgment, basic protection
of the nation will not be sufficient until Phase II
is completed.
As Dr. Henderson, former director of the worldwide
smallpox eradication program,
said in 1999: “One can only speculate on the
probable rapidity of spread of the smallpox virus
in a population where no one younger than 25 [now
~30] years of age has ever been vaccinated and older
persons have little remaining residual immunity."
Does vaccination work? Yes, it is very effective
and prevents smallpox. Dr. Henderson and his colleagues
demonstrated this dramatically with great benefit
to mankind.
The vaccine (vaccinia virus): We have enough for
everyone living in the United States. The new Acambis
product is expected to have a similar risk profile
to the “old” recently relicensed Dryvax
product. Newer vaccines that may be safer are still
2 or more years away. Drs. Fuci, Gerberding and Monath
know far more about this than I. They too are far
more qualified than I to comment upon the likelihood
and risks of genetically engineered smallpox variants.
How safe is the vaccine? 14,168,000 persons were
vaccinated in 1968, with 9 deaths, 7 of them in children.
The 2 deaths in persons over 10 were a teen (age 16)
with aplastic anemia and an adult (age 62) with leukemia.
Using today’s guidelines we would not vaccinate
any children, and we would screen out and not vaccinate
the teen and the adult. Deaths in children and sick
adults can be expected not to occur today. In 1968
there were 114 cases of accidental vaccination of
others with 1 death (a child). Mostly these were child-to-child
transmissions (70%) and the balance (26%), with 2
or 3 exceptions, were between parent/grandparent and
child. There is substantial historical evidence of
safety in adults from the US military since World
War II, the Israeli Military in the early to mid 1990s,
and the recent Israeli civilian experience, There
have been no reports of vaccine related deaths.
However, we do not have to rely entirely on historical
data or recent Israeli experience. As of January 27,
over 2000 military hospital workers have been vaccinated,
including staff at Walter Reed. This very sophisticated,
modern hospital has a hematology/oncology ward, transplant
unit and neonatal intensive care unit. These are all
areas where you would not want to accidentally spread
vaccinia virus from recently vaccinated workers to
patients. This has not happened. Vaccinated health
care workers continued caring for patients using semi-permeable
membrane dressings, long sleeves, and scrupulous hand
washing. The semi-permeable membrane dressing reduces
the shedding of vaccinia virus from the vaccination
site into the environment by 95% to 99%. In addition,
patient contact with recently vaccinated workers was
minimized in the hematology/oncology ward, transplant
unit and neonatal intensive care unit.
Primary or first-time vaccinees receive 3 jabs of
the special bifurcated needle and 97% have a successful
vaccination or take rate. Persons who had been vaccinated
years ago (revaccinees) receive 15 jabs and have a
99% take rate. Sick leave day(s) off are taken by
4% of primary and 1.5% of revaccinees. Almost all
sick leave has been 1 to 2 days off with 1 day being
the most common. The military use the semi-permeable
dressing for hospital workers but not for troops who
use a band-aid. This is consistent with the CDC guidelines.
Complications have been minor and are occurring at
the expected rates.
Full data on our military are still classified as
to numbers but CDC and FDA have this information and,
in terms of complications and absenteeism, there is
nothing to suggest anything much different from the
above.
It is very important to remember that many of the
military are first-time vaccinees, a group at higher
risk of vaccine complications than revaccinees, and
similar to a well screened group of civilian health
workers. In only a few weeks we will have recent hard,
current data on serous complications, minor complications
and absenteeism. However, everything to date suggests
that the widely reported fears of some health workers
either for themselves, their fmailies or for their
patients are not well founded.
As our recent experience with adult first-time vaccinees
is somewhat limited, the plan to vaccinate 500,000
military and 500,00 civilian first responders will
expand our experience base and, I believe, put to
rest many fears. We are observing and evaluating as
we go. We can contemporaneously, without pausing,
adjust policy if the risks are greater than expected.
Otherwise, we can and should rapidly move to 10,000,000
in Phase II, continue collecting data, recalibrate
if needed, and finally make vaccination available
to the general adult public. Anything less than completing
Phase II is half-built protection. If a hospital,
city or state chooses to do less, it is at higher
risk, becomes a preferred target and weakens national
defense.
It is worth remembering that those at greatest risk
of vaccine complications are also at greatest risk
of dying from smallpox. Thus, the more we do careful
screening, education and vaccination pre-attack, the
more the most vulnerable among us will be protected.
CHILDREN & SMALLPOX VACCINATION
Fatality rates from smallpox in children can approach
50%. Children are one of our most cherished assets.
Gareth, my 2 and 1/2 year old grandson is certainly
at the center of my life. So why not vaccinate children
now, before an attack? The reasoning goes like this:
1 – The worst complications and the most deaths
from vaccination, including deaths in otherwise healthy
children, occur in children under 10.
2 – Arguably the worst complication –
Post Vaccinal Encephalitis (PVE) - cannot be predicted
and cannot be treated. This is rare and occurs most
commonly in young children (15 of 16 cases in 1968).
In 1968, 4,900,000 children under 10 were vaccinated
for the first time, only 15 got PVE (0.0003%), but
4 died (26%) and 4 had complications including brain
damage and paralysis of the arms and legs.
3 – Children are most likely to be accidentally
infected or accidentally vaccinated by others. In
1968, with a total of 14,168,000 vaccinations (39%
primary vaccinees) there were only 114 reported cases
of accidental vaccination of others with 90 of these
cases (79%) occurring in children. Children are most
commonly infected by another child (70% of cases)
or by an adult caregiver. 96% of the cases where one
person accidentally vaccinated another were either
child-to-child or between caregiver and child. Only
one occurred in a hospital setting where a recently
vaccinated nurse cared for a child with active eczema.
This is also a good example of why it makes sense
to use the semi-permeable membrane dressing and schedule
recently vaccinated staff not to care for patients,
such as eczema and immune disorder patients, at high
risk of accidental immunization.
4 – Complications in children, ranging from
mostly minor to, very rarely, severe, are quite common.
For a mother often any complication is seen as severe,
even though in the grand scheme of things it may be
inconsequential. My own son had a smallpox vaccination
complication in the 1960s, I don’t remember
it, his mother does! Based on 1968 data, children
under 1 can expect to experience 1 complication for
every 8,900 vaccinated, for children from 1 through
9 years of age the expected complications would be
about 1 in 12,000. This is a lot of complications
even though the vast majority would not be severe.
5 – Post-attack, children are far easier to
isolate than adults. In a smallpox emergency we would
say stay home until your local vaccination point is
ready in somewhere between 1 and 5 days. Hopefully,
this will be closer to 2 or 3 days. Then children
will be rapidly vaccinated and protected before they
are infected. The benefits of vaccination would now
greatly exceed the risks.
6 – The more adults that are vaccinated pre-attack,
the less likely it is there will be widespread transmission
and transmission to children post-attack. In my judgment,
this is a good reason to modify Phase III of the President’s
plan and move from allowing adults in the general
public to be vaccinated to encouraging adults to be
vaccinated.
What would I do for my family? I want the adults
vaccinated or revaccinated so long as they had no
contraindications. I’d say no for any children
under 10. And I would want a tested and proven mechanism
in place for rapid post-attack vaccination of every
remaining unvaccinated adult and all children so that
smallpox deaths would be reduced to a minimum (In
a post attack scenario there are very few contraindications
to vaccination.). In my judgment this approach offers
the best protection with the least risk, pre- and
post-attack, for children, adults and the nation.
A NOTE ABOUT MODELS
There are many mathematical simulations or models
of a smallpox attack extant. They are confusing to
many. However, it is my understanding, with the possible
exception of one model, that, when the assumptions
are well understood and corrections are made so that
the populations being considered are comparable, the
results from various models are remarkably similar
and favor the President’s plan. If and as further
modeling takes place and is used to inform policy
and to test the feasibility of alternative program
structures at the federal and state levels, it is
vital that models be reality based and comprehensible
with clear and explicit assumptions. The work of Ed
Kaplan (Yale), Larry Wein (Stanford) and David Craft
(MIT) is exemplary and their expertise represents
a real national resource in this area.
JURISDICTIONAL ISSUES
These are non-trivial. The Homeland Security Act
may have eliminated these concerns at the federal
level, but perhaps not. At the state and local levels,
jurisdictional issues remain. A colleague (Ken Bloem
– He has led several leading academic medical
center hospitals across the country) and I have been
working on a concept that recognizes the unique problems
in coordinating a response to bioterrorism events
in the United States. Our constitutional division
of responsibilities between the federal government
and the states is only one complication. There are
overlapping agency jurisdictions at the federal, state
and local levels and we have a highly unusual blend
of private and public organizations whose activities
must be coordinated.
We are considering an approach that would use an
incident command structure with incident commanders
who may not be traditional public health professionals,
but would simultaneously be federal and state employees
reporting directly to the governor of a state and
to a deputy or under-secretary in Homeland Security.
These issues are not the subject of this hearing but
they are of vital importance and I mention them only
to highlight their importance. We now have all the
material things needed to control a smallpox attack.
It is time to imaginatively and realistically address
the organizational and human issues that are essential
for an effective response.
LIABILITY
I will not address liability as great progress has
been made in this area and others are far more expert
than I.
SERIOUS MYTHS & MISCONCEPTIONS
1 – The smallpox vaccine is so dangerous it
should not be used before an actual case of smallpox
occurs – WRONG.
There are differences of opinion. However, the historical
data and current experience demonstrate that with
careful screening, the use of the semi-permeable membrane
dressing and limiting vaccination to healthy adults,
the risks of severe vaccine complications and particularly
deaths can be reduced to extremely low levels. These
levels are far below the levels of many avoidable
risks we all accept on a daily basis and far lower
than what many health professionals are anticipating.
It is essential to distinguish between vaccine side
effects in children under 10 and all others as well
as between first-time vaccines and repeat vaccinees.
Children under 10 are at highest risk, repeat adult
vaccinees are at lowest risk. Deaths in healthy adults,
whether previously vaccinated or not, can be expected
to be extremely low.
2 - A contagious smallpox patient is always visibly
sick with a rash so there is no risk to health workers
if a person infected with smallpox is not obviously
sick with a rash – WRONG.
CORRECT – Transmission can occur without a
visible rash, with the person not feeling well but
not so sick as to preclude travel and walking around.
3 - Vaccinating within a 2, 3 or 4-day window after
exposure may/will prevent disease - WRONG.
CORRECT – Vaccination within 5 days of exposure
may prevent death, and probably results in less serious
disease (lower fatality rate), but there is little
to no evidence that vaccination after exposure prevents
disease.
4 - If doctors are just properly trained they will
be able to quickly identify the first case or two
of smallpox –WRONG.
First case(s) will be diagnosed late: Smallpox doesn’t
look like much until day 3 or 4. Confirming may take
another day or two. Once the first case is confirmed,
there will be over-diagnosis. No amount of training
can prevent this. As rapid diagnosis cannot be assured,
and it would not be surprising if it took longer than
3 or 4 days, this is an additional compelling reason
for rapidly completing Phase II of the President's
plan.
5 - Identifying individual cases, tracing contacts
with targeted vaccination of contacts, isolation and
quarantine (Often called “Ring Vaccination”)
is the preferred strategy to contain a smallpox attack
– WRONG.
In any serious terrorism scenario, this will not
work. See the comparison of post-attack ring vaccination
and immediate mass vaccination by Kaplan, et al. With
ring vaccination, we can also anticipate failure of
quarantine, serious disruption of commerce and quite
possibly civil unrest. As the first case or two are
identified and obvious case contacts are vaccinated,
we should simultaneously ramp up for local mass vaccination
in the area of the first case(s) and be ready for
more widespread national mass vaccination if a case
occurs in a second geographic area.
All of the above have substantial implications for
planning pre- and post-attack national control strategies.
I submit as part of my written testimony a recent
article by Dr. Ken James and myself that carefully
reviews and considers many of the issues I have been
raising during this hearing. It proposes a framework
not only for the US but also for other countries to
consider as they, too, face the possibility of smallpox.
I also include a recent article by Warren Kaplan,
Esq. that, although using Massachusetts as an example,
takes a national perspective on federal and state
legal issues as they impinge upon mounting an effective
response to the bioterrorism threat.
THE PREFERRED NATIONAL STRATEGY
1 – Pre-Attack: Implement the President’s
plan in a timely manner with real-time evaluation
of Phase I results as we move immediately to Phase
II. There is no argument for delay and protection
is not adequate until Phase II is complete. I would
more actively encourage vaccination of the general
population once first responders have been vaccinated.
This will decrease post-attack transmission, decrease
panic and make post-attack control much easier. I
would also consider using the semi-permeable membrane
dressing for everyone who is vaccinated not just hospital
workers. Why not decrease the risk of accidental vaccination
to the lowest possible levels?
2 – Post- Attack: With one or two cases in
the nation, I recommend: A) in the area where the
first case(s) occur immediately vaccinate obvious
contacts and simultaneously initiate mass vaccination;
B) mobilize for national mass vaccination; and C)
move to national mass vaccination if there are any
cases in a new geographic area. .
REMAINING PROBLEMS
Clear, concise, accurate information to the public
and to the medical and public health community is
needed. This is getting better but further improvement
is essential. Open, honest, direct and forthright
communication including acknowledging uncertainty
and errors are essential to gain and maintain the
trust of the public in government.
Although we have all the material to control an outbreak
of smallpox, administratively, we are far from ready.
Mass vaccination tomorrow would be chaotic. Who is
in charge and who should do what are often not clear.
Plans should emphasize simple methods and procedures
that recognize we will be vaccinating in a big hurry.
To do this well requires not just advance planning,
but the elegance that comes from simplicity.
Finally, the public health system is, by its nature
and culture, not an emergency response system and
never has been. We need to consider an integrated
federal-state incident command structure with Emergency
Medical Services and the acute care system taking
the lead role for mitigating the adverse health impact
of any bioterrorism event. In this conceptualization,
public health, particularly laboratories and epidemiologic
intelligence, would play an essential supportive,
but not directive, role.
Of the utmost importance, if smallpox or some other
bioterrorist threat becomes a reality, we must be
certain our plans will work. Therefore, we must move
to rapidly complete Phase II of the President’s
plan, and whatever our ultimate organizational structure,
we must realistically and regularly test our post-attack
plans.
CONCLUSION
This is a terrorist threat we have anticipated and
can largely prevent. The nation has made tremendous
strides in the past 16 months. The President’s
plan is sound, takes the teeth out of the smallpox
weapon and decreases the smallpox risk for us and
the rest of the world. But we must keep moving. We
can simultaneously be prudent, avoid needless risk
and move ahead rapidly.
Putting the President’s smallpox control plan
into effect is but one step in a long and arduous
journey on the road to improved national protection
against a variety of bioterrorist threats.
Finally, as was the case with the interstate highway
program and the space program, I believe we can look
forward to many positive and unanticipated benefits
to our bioterrorism preparedness initiatives.
Thank you for offering me the opportunity to testify.
I welcome questions.
William J. Bicknell, MD, MPH
Professor of International Health, Socio-Medical Sciences,
and Community Medicine
Department of International Health
Boston University School of Public Health
715 Albany Street, T4W
Boston, MA 02118-2526
USA
Cell Phone: (1) 617-283-5775 (with voice mail)
Email: <wbicknel@bu.edu>
Main Office Phone: (1) 617-638-5234
Fax: (1) 617-812-5834
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