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2024-4-26 13:44:45


Easing bio-security on reconstituted 1918 killer virus raises concerns
submited by kickingbird at Oct, 22, 2004 12:0 PM from yahoo news and PromedMail

The decision by a team of U.S. researchers to ease bio-security precautions for a reconstituted version of the 1918 pandemic flu virus - the most lethal killing machine in viral history - is sparking debate within the international scientific community. 

Fears that a genetically engineered cousin of the virus responsible for the infamous Spanish flu might accidentally escape from a lab have led to calls within the scientific world for a international meeting to iron out the conditions under which it can be studied.

"Obviously any chance of escape of a virus of that nature would be really very worrying indeed," Australian virologist John Mackenzie said Thursday. The virus was made at the National Microbiology Laboratory in Winnipeg.

The head of the World Health Organization (news - web sites)´s global influenza program said he isn磘 certain that work on the virus needs to be restricted to the most secure facilities, but the agency would be open to hosting a forum on the issue.

"What we mustn磘 forget is that what they磖e working on is not the 1918 virus," Dr. Klaus Stohr cautioned in an interview from Geneva.

"(But) if we find ... some disagreement internationally on which level of bio-safety is the appropriate one, then we would definitely consider pulling a group of experts together and come up with a WHO opinion on this subject."

The WHO estimates the 1918-19 pandemic, caused by an H1N1 influenza virus, claimed between 20 million and 50 million lives worldwide.

Scientists drawn into the debate are quick to insist they are not accusing lead researcher Yoshihiro Kawaoka of the University of Wisconsin of bad judgment. Kawaoka has a reputation for caution among his peers.

"It´s not like he´s sort of the cowboy running around doing these experiments," said Richard Webby, an influenza virologist at St. Jude Children´s Research Hospital in Memphis, Tenn.

Webby praised Kawaoka for building the recombinant virus in a bio-security level 4 facility (the most secure level) at the Winnipeg lab. Other teams that have worked on variations of the 1918 virus have done so in level 3 facilities, he pointed out.

Still, Webby said his institution wouldn磘 work with a 1918 variant in anything less than a level 4 lab. It´s a view shared by Dr. Frank Plummer, director of the Winnipeg lab.

"We磖e more comfortable working on it in level 4," Plummer said. Asked why, he simply answered: "Concerns about safety and just being ultra cautious."

Kawaoka, who was travelling in Asia and not available Thursday, is based at the University of Wisconsin in Madison. His work continues at a Level 3Ag - basically a Level 3-plus - laboratory there.

Before moving to that level, his team tested the virus´s susceptibility to anti-viral drugs in mice. They also tested the protection offered by flu vaccines, determining that vaccines for contemporary H1N1 strains protected about 70 per cent of exposed mice from developing disease.

"We essentially reassessed the risk of the (future) experiments based on the new information," Kawaoka told a meeting of the U.S. National Institutes of Health  recombinant DNA advisory committee in late September.

"I should mention that the experiments were done only in mice and we do not know to what extent the mouse data can be extrapolated."

The decision to work on the virus in a Level 3 lab is in complete accord with U.S. recommendations.

 

"You may criticize the regulations, but he´s certainly acting within the U.S. regulations," Plummer said. "That may change. I know there has been debate in the U.S. about what level of containment is appropriate."

That debate has been reflected in a thread on ProMed, an electronic forum maintained by the International Society for Infectious Diseases.

"A valid risk assessment of the consequences of release would dictate that this research be carried out in a certified maximum containment (BSL4) facility," wrote biosafety consultant M.E. Kennedy, former biosafety director of the Laboratory Centre for Disease Control, the precursor to the Winnipeg lab.

There is precedent for concern. Two lab accidents in China earlier this year sparked a new cluster of SARS cases. And it is believed the H1N1 influenza virus, which stopped circulating in 1957, was reintroduced into humans in 1977 through a lab accident.

Still, all involved in the debate know adding theoretical protection will come at a practical cost.

"It certainly would impede science. It would slow it down considerably," Plummer said.

"So that´s what you have to balance it against. The biosafety-biosecurity dimension versus the speed of progress on understanding this virus better."


Weeks before, hot debate of the biosafety issue took place on Promedmail. here is some of the comments.--------Moderator

Date: Fri 8 Oct 2004
From: Karl M Johnson <KarlMJohnson@aol.com>

A comment on appropriate level of containment
---------------------------------------------
Professor Kawaoka´s team is to be congratulated for successful recreation
of the 1918 influenza virus with it apparent increased virulence for mice.
But if that virulence transfers to humans, I am deeply concerned about his
decision to take the agent from BSL-4 [biosafety level 4] containment to
BSL-3 [biosafety level 3] after finding that level of pathogenicity. We
have already experienced 3 breaks in technique and containment of the SARS
coronavirus this year. Escape of this influenza strain could lead to a
repeat of history that would be completely preventable if that virus were
"put back in its box".

Personally, I would never permit work with this agent under conditions
lower than BSL-4. The University of Wisconsin and appropriate federal
agencies should convene an emergency meeting to sort this out, ensuring
that Dr Kawaoka has ongoing access to BSL-4 containment so that he can
continue this undeniably important work.

--
Karl M Johnson
<KarlMJohnson@aol.com>

[Dr Johnson expresses valid concerns about the disease security aspects of
Dr Kawaoka´s research, particularly in view of the finding of the enhanced
pathogenicity of the construct containing the 1918 HA subunit. His call for
a reassessment of the situation should be heeded. - Mod.CP]


Date: Fri 8 Oct 2004
From: Myron Pulier "<pulierml@umdnj.edu>

Further comment on the disease security issue
---------------------------------------------
In the press report cited in the ProMED-mail post archived as "Influenza A
virus, virulence, 1918 pandemic strain 20041007.2754", Dr Kawaoka seems to
indicate that the possibility of treatment of other influenza type A
strains with "Tamiflu" (oseltamivir) makes biosafety level 3 containment
sufficiently prudent for his new 1918 pandemic-like one.

However, shortening duration of symptoms once they appear and preventing
development of clinical illness by initiating treatment shortly after
exposure does not necessarily amount to maintaining sufficient control of
person-to-person spread to prevent another pandemic, should the virus
infect someone. Even in clinical research, few drugs are 100 per cent
effective; and in actual clinical use, effectiveness is less than efficacy,
so that some patients may not respond well to treatment. Prophylaxis
against illness is not the same as prevention of infection and leaves open
the potential for transmission by an asymptomatic carrier.

Furthermore, oseltamivir has not been tested clinically against any
comparably virulent strain, and potential of the virus for rapid extension
throughout the lungs might overwhelm the protection offered by the drug,
however unlikely that may seem at present. Presumably Dr Kawaoka has
determined through experiment that his particular strain happens not to be
one that is resistant to oseltamivir at pharmacologic concentrations, and
hopefully there will be no opportunity for his viruses to pick up or
develop alleles that confer resistance.

Nonetheless, with stakes so high, it may pay to return the reconstructed
virus to a level 4 facility... and to take special steps to secure that
facility against bioterrorists.

--
Myron L Pulier, MD
Clin Assoc Prof Psychiatry
UMDNJ-NJ Medical School
<pulierml@umdnj.edu>


Date: Sun 10 Oct 2004
From: Mark Hughes <mthughes@colostate.edu>


The inhibitor sensitivity of constructs containing 1918 HA, NA or M genes
-----------------------------------------------
The HA, NA, and M gene products from the 1918 strain of influenza A
(H1N1) virus have been tested for sensitivity to oseltamivir,
zanamivir, and amantadine/rimantidine. The reference is: Tumpey TM,
Garcia-Sastre A, Mikulasova A, Taubenberger JK, Swayne DE, Palese P,
Basler CF. Existing antivirals are effective against influenza
viruses with genes from the 1918 pandemic virus. Proc Natl Acad Sci
USA. 2002 Oct 15;99(21):13849-54.

--
Mark Hughes, Ph.D.
Arthropod-Borne and Infectious Disease Laboratory
Colorado State University,
Fort Collins, CO
<mthughes@colostate.edu>

[ProMED-mail is indebted to Mark Hughes for drawing attention to this
paper. In the paper, the authors report similar experiments to those
of Kawaoka and colleagues and state that: "The potential impact of a
re-emergent 1918 or 1918-like influenza virus, whether through
natural means or as a result of bioterrorism, is of significant
concern. The genetic determinants of the virulence of the 1918 virus
have not been defined yet, nor have specific clinical prophylaxis
and/or treatment interventions that would be effective against a
re-emergent 1918 or 1918-like virus been identified. Based on the
reported nucleotide sequences, the authors have reconstructed the
hemagglutinin (HA), neuraminidase (NA), and matrix (M) genes of the
1918 virus. Under biosafety level 3 (agricultural) conditions, we
have generated recombinant influenza viruses bearing the 1918 HA, NA,
or M segments. Strikingly, recombinant viruses possessing both the
1918 HA and 1918 NA were virulent in mice. In contrast, a control
virus with the HA and NA from a more recent human isolate was unable
to kill mice at any dose tested. The recombinant viruses were also
tested for their sensitivity to U.S. Food and Drug
Administration-approved anti-influenza virus drugs in vitro and in
vivo. Recombinant viruses possessing the 1918 NA or both the 1918 HA
and 1918 NA were inhibited effectively in both tissue culture and
mice by the NA inhibitors, zanamivir and oseltamivir. A recombinant
virus possessing the 1918 M segment was inhibited effectively, both
in tissue culture and in vivo, by the M2 ion-channel inhibitors
amantadine and rimantadine. These data suggest that current antiviral
strategies would be effective in curbing the dangers of a re-emergent
1918 or 1918-like virus." - Mod.CP]


Date: Tue 12 Oct 2004
From: Ronald Voorhees <Ron.Voorhees@DOH.STATE.NM.US>


The antiviral sensitivity of 1918-1919 influenza virus and biosafety
-----------------------------------------------
I read with great interest the research pinpointing the virulence
factors of the 1918-1919 influenza virus. I also experienced
disbelief, and a great deal of discomfort, regarding the decision to
relocate the reconstructed 1918-1919 influenza strain from a BSL4
facility to a BSL3 facility, based on its susceptibility to antiviral
medication. I would like to raise several concerns and, hopefully,
spark a prompt revisiting of this decision.

1. Given the limited extent to which antiviral drugs shorten the
duration and severity of disease due to the currently circulating
strains of influenza, is there solid clinical evidence of the extent
to which these drugs would modify the clinical course of the vastly
more virulent 1918-1919 strain? What would be the pattern and
rapidity of resistance to these drugs? What would be the
recommendations for their use in prophylaxis and treatment?

2. Even if these antiviral agents were found to be extraordinarily
effective against the 1918-1919 virus, there is a totally
insufficient supply of these drugs to cope with an accidental
release. (We have just researched this question in light of the
2004-05 vaccine shortage: the current national supply of all the
antiviral drugs combined would be nowhere near enough to effectively
cope with an outbreak, should one occur.)

3. What security measures are in place to absolutely preclude the
release of the 1918-1919 virus? (Given the evidence that released
strains of anthrax, plague, and other agents may have originated from
highly secure facilities, is there evidence that this is even
possible?)

4. What emergency response plans are IN PLACE to prepare for the
potential release of this virus?

These are not simply academic questions, they are the essential
public health and policy questions that must be answered in order to
safeguard the public from the unleashing of a pandemic. Unless they
can all be answered in a robust fashion that assures that public
health is now being protected, and will be in the future (and I do
not believe that they can be), the decision to relax the biosafety
level for this virus seems to be extremely short-sighted; hopefully
it will not also prove disastrous.

Experience, and the fact that, ultimately, all systems rely on human
beings with all of our inherent limitations, would suggest that if
this virus is to be maintained, it should only be maintained in a
BSL4 facility and then only with extraordinary physical and human
security measures that substantially exceed those used in the past
for maintaining variola virus. I strongly support Dr. Karl Johnson´s
suggestion for an emergency revisiting of this decision.

--
Ronald E. Voorhees, M.D., M.P.H.
Chief Medical Officer
New Mexico Department of Health
USA
<Ron.Voorhees@DOH.STATE.NM.US>

[The data obtained by Tumpey and colleagues provide reassurance that
constructs containing the hemagglutinin gene (the putative virulence
factor) of the 1918/19 pandemic influenza A virus will remain
sensitive to currently available antivirals. The deployment of these
drugs is likely to provide adequate protection for laboratory staff
and diminish, but not eliminate, risk of transmission of influenza
virus to others. If influenza virologists are convinced that the
1918/19 pandemic influenza virus was as lethal as generally assumed,
it would seem prudent, in my view, to confine experimental work to
biosafety level 4 facilities as advised by Karl Johnson and Ronald
Voorhees. - Mod.CP]


Date: Sun 10 Oct 2004
From: M.E. Kennedy <kenne58@attglobal.net>


Further comment on the appropriate containment level
-----------------------------------------------
There should be no question as to the containment level for work with
this strain of influenza A virus. The differences between containment
level 3 (BSL3) and containment level 4 (BSL4) are significant, both
in the physical aspects of the laboratory, and, perhaps more
importantly, in the operational practices.

A valid risk assessment of the consequences of release would dictate
that this research be carried out in a certified maximum containment
(BSL4) facility.

--
M.E. Kennedy
Consultant in Biosafety
Ashton, Ontario Canada
<kenne58@attglobal.net>
(Formerly Director Office of Biosafety,
Laboratory Centre for Disease Control
Health Canada, Ottawa, Ontario, Canada)


Date: Wed 13 Oct 2004
From: Jocelyn Kaiser <jkaiser@aaas.org>


The Kawaoka Lab´s Justification
-------------------------------
I磎 wondering whether those discussing the Kawaoka lab´s experiments
have seen a presentation Dr. Kawaoka recently gave on the risk
assessment that led to the decision to move from a BSL-4 facility to
a BSL-3:
<http://www.webconferences.com/nihoba/21_sep_2004.html>?

The direct link to Dr. Kawaoka´s slides is the following:
<http://www.webconferences.com/nihoba/ppt/Biosafety%20final%20Kawaoka.pdf>

Does the information here change anyone´s conclusions?

--
Jocelyn Kaiser
Science Magazine
1200 New York Avenue NW
Washington, DC 20005
<jkaiser@aaas.org>

******
[2]
Date: Thu 14 Oct 2004
From: Edward Hammond <hammond@sunshine-project.org>


On Responsibility for Assignment of Containment Levels
---------------------------------------------------
The most critical issue raised by the Kawaoka work with the 1918
chimera at BSL-3 is not that of the assignment of containment levels
for specific experiments, rather, it is that there is no effective
national system ensuring consistency, responsibility, and good
judgment in such research.
In addition to reverse genetic engineering of influenza, Dr. Kawaoka
has NIAID funding to perform reverse genetic engineering of Ebola
virus. Similarly, Dr. Katze of the University of Washington in
Seattle has proposed to conduct aerosol challenge of primates with
influenza containing up to 5 of the 1918 genes at BSL-3.  (These
grants may be viewed in the NIH CRISP database.)

As was noted in the Sunshine Project´s recent report on IBCs, even
the 1st reported creation of a 1918 chimera and subsequent
experiments at the USDA BSL-3ag facility in Athens, GA were not
reviewed by any IBC. Thus, it is unclear how USDA arrived at its
determination of BSL-3ag containment (not BSL-4) for its experiments
with 1918 constructs.

It is reasonable to suspect that more laboratories will become
interested in pandemic influenza and other experiments involving
manipulation of very dangerous viruses (e.g. SARS). As such
experiments proliferate in the absence of binding rules, there is a
distinct danger that the lowest containment level assigned by any IBC
will become a de facto standard for similar experiments elsewhere. To
wit, the University of Washington is presently trying to convince
USDA to release 1918 constructs to it, despite the fact that
UW-Seattle does not have a BSL-3ag facility. (That´s not an
endorsement of USDA´s BSL-3ag designation -- it is an illustration of
how biosafety levels are being dragged down.)

Unfortunately, several years after the 1918 construct experiments
began, the formal federal advice for containment in pandemic
influenza experiments remains BSL-2.  At a recent meeting of the NIH
Recombinant DNA Advisory Committee (RAC), it was stated that the RAC
will not use its abilities to effectively compel compliance with its
advice (through limiting access to funding). Rather, the RAC will
provide voluntary "points to consider" to Institutional Biosafety
Committees which, as the Sunshine Project recently demonstrated, are
frequently dysfunctional.  This is woefully inadequate.

At the RAC meeting, the Sunshine Project submitted 11 written
questions concerning the absence of an enforceable system imposing
responsibility on PIs, IBCs, and institutions conducting such
research.  These included a pointed question about national and
international availability of tamiflu. Sadly, none of the questions
was answered by the RAC and, in fact, when I spoke at the meeting,
the RAC Chair deemed my concern about its reticence to flex its
muscle to ensure safety with pandemic influenza and other experiments
as "irrelevant", because the RAC has (by means unknown) already
decided it will produce nothing more than 磒oints to consider?in
response to concerns raised about safety in experiments such as Dr.
Kawaoka´s.

Responsibility is needed that extends beyond the moral responsibility
that some PIs accept.  I mean laboratory safety regulation (not
guidelines) that establish potential criminal and civil liability for
PIs, IBCs, institutions, and funders in the event of an accidental or
deliberate release.  30 years ago at Asilomar, biotechnology
practitioners agreed to an accountable and responsible IBC system,
and thereby they forestalled regulation.  But now, that system is no
longer accountable and, in too many cases, no longer responsible.

The answer is not to quarrel over biosafety levels for a particular
experiment, rather, it is to impose accountability and liability
through comprehensive laboratory safety legislation, something the US
does not have.

--
Edward Hammond, Director
The Sunshine Project
P.O. Box 41987
Austin  TX  78704
USA
<hammond@sunshine-project.org>

[No support has been expressed so far by correspondents for the
decision to conduct reverse genetic experiments with the 1918/19
pandemic strain of Influenza A (H1N1) virus at containment level 3
rather than containment level 4. It is hoped that those conducting
this type of research will take note of the concern expressed by
ProMED-mail correspondents and will reconsider their risk
assessments. This thread is now cut. - Mod.CP]


New  Scientist Article
Source: http://www.newscientist.com/news/news.jsp?id=ns99996554

Experts fear escape of 1918 flu from lab

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 breathing”.

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