By Shannon Brownlee
Page 2 of 2 (Page
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Henderson worries that an outbreak of
smallpox in the United States today could be similarly explosive.
"We've looked at what would happen in a small outbreak,
100 cases, in Baltimore," he says. "The first place
you would see patients is in the hospital." There would
be little to do for them, he says, except provide comfort
and IV fluids, and place them under strict quarantine.
To prevent the outbreak from spreading,
health officials would need to vaccinate all people with whom
the patients had had face-to-face contact, a task that would
be more difficult than it was 30 years ago in Africa and on
the Indian subcontinent, where most people still traveled
on foot.
Today, Americans could be across the country,
if not in Paris or Tokyo, within a day after being exposed.
By the time they were tracked down, at least some of that
first round of contacts would already be sick, says Henderson.
It would be too late to vaccinate them.
"Our guess is that in four to five
weeks, all 8 million doses of vaccine in the current US stockpile
are gone," says Henderson. He tips back in his chair
for a moment before continuing: "By the second wave,
their contacts will be scattered all over the country. With
air travel what it is today, this is a global catastrophe.
And if it happens in Brazil, or Mexico, or wherever, it's
our problem, too."
How likely,
then, is a smallpox attack?
Jonathan Tucker, director of the Chemical
and Biological Weapons Nonproliferation Program at the Monterey
Institute of International Studies, and author of Scourge:
The Once and Future Threat of Smallpox, estimates that the
risk is minuscule -- even in light of September
11.
"The number of groups that could
use smallpox is very, very small," he says. "They
need a motive to cause widespread destruction" that could
eventually wash over them and their backers as well. And,
he said, "they have to be able to cloak their activities."
That is small comfort given what happened at the World Trade
Center and Pentagon.
But to use smallpox, they would also need
the highly technical expertise for culturing the virus, transporting
it either as a powder or suspended in liquid, and then dispersing
it into the air for intended victims to breathe. Anti-terrorism
experts, and Alibek and Henderson, believe that expertise
is available on the international market in the form of out-of-work
Russian biologists.
"In bioweapons, the most sensitive
product is knowledge," says Alibek. Several dozen of
his former colleagues from Vector and other Soviet bioweapons
labs remain unaccounted for. In the 1990s, Iranian officials
recruited former Biopreparat biologists and engineers, offering
as much as $5,000 a month -- a huge sum for Soviet scientists
at the time -- to bring their skills to Iran. It's unknown
how many, if any, scientists took the offer.
Most would-be terrorists, says Bill Patrick,
a former bioweaponeer who worked at Fort Detrick, Md., before
the American offensive biological weapons program was dismantled
in 1969, are incompetent when it comes to biology.
The Japanese cult Aum Shinrikyo, for
example, failed at repeated attempts to release anthrax before
finally managing in 1995 to poison several thousand commuters
and kill 12 in the Tokyo subway system with the nerve agent
sarin.
Only a state-sponsored
group or terrorists with a lot of money and connections would
be able, in Patrick's opinion, to acquire the smallpox virus
and the means for wielding it as a weapon.
No one is certain whether that would include
Osama bin Laden, leader of the al Qaeda terrorist group that
American officials say organized the September 11 attacks.
But if those hurdles were surmounted,
it would be quick work for a decent virologist to produce
enough virus for a limited assault.
Bioweaponeers in the US program, says
Patrick, had begun weaponizing smallpox before the US biological
weapons offensive effort was halted. "We made a beautiful
powder for smallpox," he says. "We used chemicals
to protect it during dissemination and aerosolization,"
which is the only effective way to spread it.
How much powdered virus would be needed
to infect 100 people with smallpox? Patrick thinks for a moment
and then replies: "A gram." That's about the equivalent
of a quarter of a teaspoon of baking powder.
When I relate Patrick's recipe for disaster
to Jonathan Tucker, he pauses for a moment before responding.
"The probability of a smallpox attack is extremely low.
But it is not zero. The potential consequences of a deliberate
release of the virus are so horrible, it's prudent to take
some precautionary measures."
The US government came to the same conclusion
in the mid-1990s, when it decided to begin rebuilding the
nation's supply of smallpox vaccine. The entire US vaccine
stockpile currently consists of 15 million doses of vaccine
manufactured 30 years ago by Wyeth-Ayerst Laboratories, though
as few as 8 million are
thought to be usable. It is stored in an undisclosed,
highly secure location, ready to be shipped at a moment's
notice.
The method used by Wyeth-Ayerst for making
its vaccine was virtually unchanged since the late 1700s,
when an English country doctor, Edward Jenner, discovered
vaccination. Jenner named his discovery after the Latin word
vacca, for cow, because his vaccine was made not from smallpox
virus, but from cowpox, a closely related virus that causes
a similar disease in cows.
As Jenner refined the vaccine, the virus
somehow transformed into a new organism, called vaccinia,
whose lineage remains uncertain to this day. Vaccinia might
be a crippled form of smallpox virus, or a hybrid between
the viruses that cause cowpox and smallpox.
The vaccine sitting in Wyeth-Ayerst's
freezers was made by first scratching the bellies of calves
and then rubbing some vaccinia virus into the skin. The virus
was allowed to thoroughly infect the calves' skin for several
days. The animals were then slaughtered, the pustules on their
bellies were scraped with a knife, and those scrapings were
freeze-dried.
The resulting
vaccine, called Dryvax, is basically freeze-dried, live vaccinia
virus, mixed with calf pus and a few stray calf hairs.
Dryvax was a great vaccine for its time
-- easily transported, stable even in hot climates -- but
it would never pass muster today with the Food and Drug Administration.
Modern vaccines must be manufactured in cell culture, or cells
that live in petri dishes inside the pristine environment
of a laboratory, and they are difficult to produce.
Nobody has
ever made smallpox vaccine in cell culture, at least not in
large quantities.
The US government is about to start. Six
years ago, the Department of Defense gave responsibility for
producing a vaccine for troops to a Pentagon office known
as JVAP, for Joint Vaccine Acquisition Program. JVAP, in turn,
contracted with a company called DynPort. Over the next 10
years, DynPort is scheduled to produce for the Pentagon 17
vaccines and antidotes against potential bioweapons, with
smallpox being the first in line.
The contract calls for the company to
deliver 300,000 doses of smallpox vaccine around 2005, at
a cost of more than $900,000.
The Pentagon's smallpox vaccine program
is described by many outside observers in less than glowing
terms. For one thing, JVAP provided DynPort with a strain
of vaccinia that traces its lineage to a vaccine never tested
in an actual epidemic.
For another, there are 2.4 million people
in the armed forces, not counting their dependents. Three
hundred thousand doses of smallpox vaccine won't be nearly
enough to protect them, says Peter Jahrling, chief scientific
adviser at the US Army Medical Research Institute of Infectious
Diseases, at Fort Detrick.
"I don't think anybody was thinking
about the fact that this is a contagious disease. They were
thinking about projecting forces into hostile areas. The fact
that those people might contract the disease and bring it
home, that wasn't really factored in."
The Pentagon has not commented on the
reasoning behind the decision. But DynPort officials say they
can make several billion doses if called upon, at a rate of
700,000 a month. The company is now poised to produce its
first test batch of vaccine. The first pilot doses will be
ready for testing on humans by March.
Just off I-270, near Rockville, the 60,000-square-foot
facility where the vaccine will be produced sparkles with
modernity. The working parts of the plant are sealed off from
the hallway where outsiders are permitted. Through a large
plate-glass window, a visitor can see inside a room where
a VW Bug-size stainless steel and glass box sits.
That's where vials will one day be filled
with vaccine. There are yellow glove-lined holes in the sides
of the box, for workers to reach their hands in and manipulate
vials of vaccine. Accordion-pleated hoses, six inches in diameter,
hang from the ceiling. The entire place is squeaky clean.
Even a fly couldn't get in, since the air flows outward at
each door to the building's exterior.
Within a year, DynPort plans to recruit
several thousand people, mostly firefighters and Peace Corps
volunteers, for a large-scale clinical trial to test its vaccine's
effectiveness. The Army has already conducted a small safety
trial, inoculating 80 healthy volunteers in Baltimore. Nobody
got sick, and everybody developed a painful pustule at the
site of the inoculation, just as people who got Dryvax did
30 years ago, suggesting the new vaccine may be as good as
the old one.
But there's no way to be absolutely sure,
short of an outbreak. The best DynPort will be able to do
is compare its version against the old vaccine. The company
will inoculate one group of volunteers with the old vaccine
and another group with the new. Then it will compare the two,
looking for antibodies and immune cells in the blood, and
the rates at which the two groups develop pustules.
The government's effort to produce a new
vaccine stockpile for American civilians has gotten off to
a slower start. It began in 1998, shortly after a public health
doctor named Peggy Hamburg arrived in Washington, fresh from
doing battle with an epidemic of drug-resistant tuberculosis
in New York.
As commissioner of health for New York
City, Hamburg had already begun preparing for the possibility
of a bioterrorism attack. When she took her new post as assistant
secretary for planning and evaluation at the Department of
Health and Human Services, Hamburg was concerned that a similar
public health effort did not appear to be underway at the
federal level.
"When I got to Washington, I called
a higher-up at HHS," Hamburg says. "I asked what
kinds of special, high-alert activities are we responsible
for in the threat of bioterrorism. He was stunned that the
department would even need to be involved in such a situation.
The department didn't view the issue as theirs."
Soon after, then-HHS Secretary Donna Shalala
gave Hamburg responsibility for reviewing the agency's role
in protecting the nation from bioterrorism, and coming up
with a road map. Hamburg began talking to other agencies,
and to security experts from the National Security Council,
the CIA and the Pentagon.
She found that few Washington officials
had grasped that a biological attack would most resemble an
infectious disease epidemic and would require a massive public
health effort. Some thought of a biological attack as a version
of a bombing.
"Somebody in the FBI told me firemen
were going to go in and defuse the pathogen," says Hamburg.
Other experts in the intelligence community were mired in
a kind of nuke-think, the misconception that preparing for
a biological threat is no different from combating nuclear
weapons.
A significant turning point came when
President Bill Clinton requested that HHS seek emergency funding
from Congress to combat bioterrorism. One of the first tasks
Hamburg set for herself was rebuilding the civilian smallpox
vaccine stockpile.
Initially, she hoped to piggyback on the
Pentagon's effort, and that DynPort could simply ramp up production
to make an additional 40 million doses for civilian use. "It
seemed like a no-brainer," she says. But representatives
from HHS, the Pentagon and DynPort found themselves, at a
series of meetings, stumbling over one reason after another
not to collaborate.
"DynPort wanted to charge us an unbelievable
amount of money if we piggybacked," Hamburg recalls.
"They claimed they would have to revamp their whole production
methodology to make millions of doses."
A former military scientist involved in
the negotiations says it was JVAP that balked, because the
military did not want its effort to be delayed by joining
forces with HHS. A spokesman for the Pentagon says that its
vaccine "remains a viable candidate for use in the civilian
stockpile" if there are problems with a civilian vaccine.
A DynPort official says the company did
not want to bid on the civilian vaccine contract because HHS
would not accept liability for civilians who would suffer
side effects from the vaccine. For every thousand people vaccinated
for smallpox, several will be hit with side effects ranging
in severity from giant, spreading pustules to gangrene. In
the past, one or two per million died from the vaccination.
After months of wrangling, Hamburg and
HHS abandoned the effort to collaborate with the military.
Last year, HHS signed a $343 million contract with a different
company, OraVax, a small biotech company based in Cambridge,
Mass., to produce 40 million doses of smallpox vaccine for
civilian use -- an amount that medical scientists believe
would be enough to stop an epidemic in the United States.
OraVax, which has since merged with Acambis,
is already making pilot-scale lots of vaccine. Originally,
it expected to produce its first 10 million doses by 2003,
with the final 30 million doses available two years later.
Now, that schedule has been speeded up, and by the second
half of 2002 a new stockpile of smallpox vaccine will be building
up.
Sometime next year, if things go according
to the current plan, the last official stocks of the smallpox
virus, the contents of the frozen vials in Atlanta and Novosibirsk,
will be destroyed. Half an hour at 250 degrees in a sterilizing
device called an autoclave ought to do it.
Similar deadlines have come and gone before.
For all the dread that smallpox inspires, and the terrifying
possibility of its reemergence as a terrorist weapon, scientists,
anti-terrorism experts and doctors remain deeply divided over
whether it would now be a colossal error to eliminate those
vials.
Peter Jahrling believes strongly that
the smallpox virus must be preserved to allow scientists to
test AIDS-era antiviral drugs against the virus for their
potential to treat victims in the event of an outbreak. Since
1995, Jahrling has led a team of scientists from Fort Detrick
to spend several months a year in the biocontainment laboratory
at the CDC in Atlanta, for such testing.
They now have a handful of candidate drugs
that can kill the smallpox virus effectively, at least in
a test tube. Jahrling also has recently succeeded in infecting
cynomolgus monkeys with variola, producing a disease resembling
human smallpox and providing an animal model for testing both
antiviral drugs and new generations of vaccine.
The need to test drugs on the actual virus
has been a persuasive argument against destruction in the
past. The virus was given its most recent stay of execution
by the WHO in 1999 in part to give Jahrling's teams more time.
DA Henderson objected vehemently to that
delay. "You have to
stretch your imagination and your pocketbook to even think
an antiviral will work," he says. He argues
that developing antiviral drugs for use with smallpox victims
will be expensive, time-consuming and ultimately pointless,
since there is no way to actually test the drug in humans
before an outbreak. In his view, the vaccine vanquished smallpox
before; it will do it again.
But Jahrling argues the ring method Henderson
used in the past won't work now. Back then, most of the population
was already immunized, so it was possible to surround a victim
with people who would not get smallpox. That is not the case
now. And these days, people are much more mobile. But the
most important reason to search for antiviral drugs, Jahrling
says, is the emergence of AIDS.
People infected with the AIDS virus have
compromised immune systems and will almost certainly resist
being vaccinated for smallpox, since the vaccine is a live
virus that could kill them. They also will be acutely vulnerable
to the smallpox virus itself, which reproduces explosively
in the body when its immune system is weakened.
In past epidemics, smallpox patients whose
immune systems were already debilitated by another illness
became human hot zones. Far more infectious than the average
smallpox patient, they sent millions upon millions of viral
particles into the air with every breath.
"With a family living in a thatched
hut in Africa exposed to one guy shedding smallpox virus,
it may be that you can successfully intervene with vaccine
four days later," says Jahrling. "But that may not
be true in an air-conditioned condo with recirculating air
where the exposed person also has HIV and is putting out a
hundred times as much virus. We just don't know."
Such uncertainties do not sway Henderson,
who wants more than anything to see the official stocks of
smallpox virus destroyed. He acknowledges that other countries
now have clandestine stocks of virus.
But the World Trade Center and Pentagon
attacks have only strengthened his belief that a ceremonial
destruction of the official stocks would serve as a moral
deterrent to rogue nations that might consider using variola
as a weapon.
It is hard to believe that moral suasion
alone can stop terrorists. Yet Henderson's wish is understandable.
His greatest accomplishment, indeed, one of the great achievements
of medical science, could be subverted by a few vials of a
tiny organism that were spirited out of Soviet bioweapons
laboratories and are now being kept alive in some unknown
freezer.
Henderson looks out the window of his
office, at a vast, dense cityscape of Baltimore. He turns
back toward the room and then says, "I thought both countries
could be trusted to keep it under lock and key."
Washington
Post October 28, 2001; Page W08