WHO Meeting Warns of Flu Pandemic
Experts Say Countries Have Not Done Enough to Prevent the Spread of
By David Brown
Washington Post Staff Writer
Saturday, November 13, 2004; Page A04
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An influenza pandemic, when it arrives, will be an immediate threat to
the health of nearly everyone on Earth, but very little is being done to
prevent its potential devastation, say experts who met this week at the
World Health Organization's headquarters in Switzerland.
A vaccine is unlikely to prevent the global spread of a pandemic strain
of flu virus, but it could save millions of lives. To do so, the world
must be ready to make, test, pay for, distribute and probably share what
will be a scarce supply, the experts concluded.
"We have a unique window of opportunity now to get our homework done to
ensure that, when it matters most, vaccine production can happen
immediately," said Klaus Stohr, the leader of WHO's influenza
activities, who chaired the two-day, closed-door meeting that ended
yesterday. "That's our chance, and we don't want to miss that chance."
In a telephone news conference, Arlene King, an official in Canada's
public health agency, said a pandemic, or global epidemic, will be "a
national health/security issue. It will be the largest public health
infectious-disease emergency we ever face in most countries, and
Avian influenza -- "bird flu" -- is the latest strain of concern. The
A/H5N1 virus, which has spread widely among chickens and ducks, has
infected 44 people in Thailand and Vietnam this year, killing 32. Should
it adapt fully to humans and be capable of easy person-to-person
transmission, it would probably spread worldwide in three to six months.
"We have in Asia an H5N1 virus which is ready to cause a pandemic,"
If the three flu pandemics in the 20th century are models, one-fifth to
one-third of the world population might be infected in the next one.
Even if only 1 percent were to die, as some experts predict, it would
cause huge social and economic disruption. The "Spanish flu" pandemic of
1918-1919 killed at least 50 million people.
The meeting, attended by about 50 people from national health
ministries, drug regulatory agencies, and vaccine companies, was held to
lay out the obstacles to developing a pandemic vaccine and begin the
work of overcoming them.
WHO has no authority to compel countries or companies to act. There was
consensus that not nearly enough money is being spent on planning for a
pandemic -- and that governments must take the lead.
"Market forces have not brought companies into pandemic vaccine
development. That's something that has been clearly recognized," Stohr
At the moment, only the United States has ordered up production of
vaccine against bird flu -- a move that even on a small scale
constitutes an expensive gamble. The Department of Health and Human
Services has contracted with two companies to make about 2 million doses
of vaccine against the currently circulating H5N1 strain, but they might
not be usable when a pandemic hits. Tests of its safety and
effectiveness in people will be conducted by April.
The obstacles to making an adequate supply of vaccine are immense. They
span the spheres of science, technology, law, politics and ethics.
Scientists will need both widespread surveillance and rapid genetic
analysis of new strains if they have a chance of catching a pandemic
early enough to produce a useful vaccine. Scientists also need to know
whether much smaller doses than usual might still be protective, which
would stretch a limited supply of vaccine.
Vaccine companies will need to make "speculative" pandemic vaccines in
small quantities while not jeopardizing their annual production of
conventional flu shots, the experts said. They will also need access to
techniques -- some covered by patents -- that will let them rapidly
create vaccine seed through a process called "reverse genetics."
Government vaccine-licensing agencies, such as the Food and Drug
Administration, will need the ability to rapidly evaluate flu vaccines
made elsewhere -- or agree to let them in automatically once they are
approved elsewhere. Countries also must decide whether they are willing
to share vaccine, and in particular send their supply to the front line
of a foreign outbreak in hopes of slowing the virus's spread.
At home, governments will need to decide who will get flu shots when
there are too few to go around -- and when the stakes are much higher
than they are this season, when the United States is facing a similar
Asked who would need to be vaccinated, Stohr answered: "Practically
A pandemic vaccine would need to protect against only one strain of flu
virus -- the newly emerged one -- rather than three strains, as is the
case with the annual flu shot. However, because nobody on Earth would
have underlying immunity to the new strain, people would need to get two
shots to be protected.
Only about a dozen companies in the world make flu vaccine. Aventis
Pasteur, which has its headquarters in France, makes about half the
world's production, which last year totaled 292 million doses. It will
probably be less this year, as the second-largest producer, the American
biotech company Chiron, lost its license to sell 48 million doses
because of manufacturing problems at its plant outside Liverpool,
The industry's ability to make vaccine against a pandemic strain is
linked to its ability to make conventional flu vaccine. Plants that make
other vaccines -- such as for measles or hepatitis -- cannot be
converted to make one for influenza. For that reason, many experts
believe it is important that more people take yearly flu shots -- and
thereby encourage companies to add production capacity.
Making seed strains and test batches of vaccine for emerging flu
viruses, however, is financially risky because the pandemic strain that
emerges may be substantially different from any in development.
For example, the bird flu strain being used in the experimental U.S.
vaccine is different enough from H5N1 strains that killed people in Hong
Kong in 1997 and 2003 that virus seed from those earlier outbreaks could
not be used. It took months to make a new one that reflected the
continuing evolution of the virus.
Such ongoing preparation is "an investment without any return, which
costs millions of dollars or euros, which compete with other priorities
in the industry," said Luc Hessel, an Aventis Pasteur executive who
attended the Geneva meeting and spoke to reporters after it.