[Paleopsych] Experts fear escape of 1918 flu from lab
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Experts fear escape of 1918 flu from lab | New Scientist
http://www.newscientist.com/news/print.jsp?id=ns99996554
10:33 21 October 04
The 1918 flu virus spread across the world in three months and killed
at least 40 million people. If it escaped from a lab today, the death
toll could be far higher. "The potential implications of an infected
lab worker - and spread beyond the lab - are terrifying," says D. A.
Henderson of the University of Pittsburgh, a leading biosecurity
expert.
Yet despite the danger, researchers in the US are working with
reconstructed versions of the virus at less than the maximum level of
containment. Many other experts are worried about the risks. "All the
virologists I have spoken to have concerns," says Ingegerd Kallings of
the Swedish Institute for Infectious Disease Control in Stockholm, who
helped set laboratory safety standards for the World Health
Organization.
Work on the 1918 flu virus is not the only worry. Some experiments
with bird flu have also been criticised as dangerous (New Scientist
print edition, 28 February 2004).
Kallings and others are calling for international discussions to
resolve the issues related to such work. "It is time for influenza
scientists to find a consensus on containment," she says. John
MacKenzie of the University of Queensland in Australia, who
investigated how the SARS virus escaped from high-level containment
labs in east Asia on three occasions after lab workers became
infected, agrees. "A meeting would be beneficial."
Gene sequencing
The researchers working on the 1918 virus say their work is vital to
understand what changes make flu viruses dangerous. So far five of the
1918 flu virus's eight genes have been sequenced, using fragments
retrieved from victims of the pandemic. Several teams have added one
or more of these genes to modern flu viruses, or plan to - in effect
partially recreating the long-vanished pandemic virus.
The latest work was done by Yoshihiro Kawaoka at the University of
Wisconsin at Madison. His team showed that adding the 1918 gene for
the surface protein haemagglutinin to modern viruses made them far
deadlier to mice. The researchers also found that people born after
1918 have little or no immunity.
The team started the work at the highest level of containment, BSL-4,
at Canada's National Microbiology Laboratory in Winnipeg. Then they
decided the viruses were safe enough to handle at the next level down,
and did the rest of the work across the border in a BSL-3Ag lab in
Madison. The main difference between BSL-4 and BSL-3Ag is that
precautions to ensure staff do not get infected are less stringent:
while BSL-4 involves wearing fully enclosed body suits, those working
at BSL-3Ag labs typically have half-suits.
Kawaoka told New Scientist that the decision to move down to BSL-3Ag
was taken only after experiments at BSL-4 showed that giving mice the
antiviral drug oseltamivir (Tamiflu) in advance prevented them getting
sick. This means, he says, that if all lab workers take oseltamivir
"they cannot become infected".
Contradictory results
Yet this assumes that the mouse results apply to humans. And the
findings have not been published. In similar experiments, Terrence
Tumpey's team at the US Department of Agriculture's poultry research
lab in Athens, Georgia, got quite different results: they found that
mice given oseltamivir still got sick and 1 in 10 died. It is not
clear why Kawaoka's mice fared better.
What is more, all the safety precautions are aimed at preventing
escape, not dealing with it should it occur. If any of Kawaoka's lab
workers are exposed to the virus despite all the precautions, and
become infected despite taking oseltamivir, the consequences could be
disastrous.
"I experienced disbelief...regarding the decision to relocate the
reconstructed 1918 influenza strain from a BSL-4 facility to a BSL-3
facility, based on its susceptibility to antiviral medication," Ronald
Voorhees, chief medical officer at the New Mexico Department of
Health, wrote on ProMED-mail, an infectious diseases mailing list.
Yet Kawaoka's decision does comply with the US National Institutes of
Health guidelines for BSL-3 agents: those causing "serious or lethal
human disease for which preventive or therapeutic interventions may be
[its italics] available". In fact, he is considered unusually
cautious. "Kawaoka should be applauded for using BSL-4 at all," says
Richard Webby, a flu researcher at St Jude's Children's Hospital in
Memphis, Tennessee.
Exposing monkeys
By contrast, the team in Georgia, the first to experiment with
genetically engineered 1918 viruses, did all its work at BSL-3Ag.
Meanwhile, Michael Katze at the University of Washington at Seattle is
planning to expose monkeys to aerosols of 1918-type viruses at BSL-3,
a step down from BSL-3Ag. The recent SARS escapes were from BSL-3
labs.
"We would have to do any such work at BSL-4," says John Wood of the
UK's National Institute for Biological Standards and Control. In the
US, the differing standards applied by different groups are due to the
fact that experiments on engineered viruses such as the 1918 flu are
approved on a case-by-case basis by Institutional Biosafety Committees
(IBCs), composed of local scientists and officials. Critics say these
are free to interpret the official guidelines in a way that suits
them.
"There is no effective national system to ensure consistency,
responsibility and good judgement in such research," says Edward
Hammond of the Sunshine Project, a biosecurity pressure group in
Austin, Texas. In a review of IBCs published this month, he found that
many would not provide minutes of recent meetings as required by law.
He says the IBC that approved the planned 1918 flu study at the
University of Washington considered only one scenario that could
result in workers being exposed to airborne virus - the dropping of
samples. Its solution: lab workers "will be trained to stop
Debora MacKenzie
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