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Oct 4, 2005 President Bush, increasingly concerned about a possible avian
flu pandemic, revealed Tuesday that any part of the country where the virus
breaks out could likely be quarantined and that he is considering
using the military to enforce it.
After the bungled initial federal response to Katrina, Bush
suggested putting the Pentagon in charge of search-and-rescue efforts
in times of a major terrorist attack or similarly catastrophic natural
disaster. He has argued that the armed forces have the ability to quickly
mobilize the equipment, manpower and communications capabilities needed in
times of crisis.
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The
possibility for aerosol transmission of influenza suggests an enormous
potential for bioterrorism.
A resuscitation of the Spanish flu is
neither necessary nor warranted from a public health point of view.
Recreating the Spanish Flu
This
briefing is extracted from: Emerging Technologies: Genetic
Engineering and Biological Weapons, Sunshine Project
Backgrounder #12, October 2003
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"...
this work was not triggered by a search for flu treatments, or the search
for a new biowarfare agent, but by a rather simple motivation:
Taubenberger and his team were just able to do it." |
October 9, 2003
Influenza as a bioweapon does not sound like a particularly grave threat.
Annual outbreaks kill many people, particularly the elderly; but a case of the
flu is generally perceived as an uncomfortable nuisance rather than a grave
threat. But flu viruses can be devastating. In 1918 and 1919, the so-called
"Spanish flu" killed an estimated 20-40 million people worldwide and, since
then, the highly changeable flu virus has resurfaced in a variety of
particularly virulent forms.
The strain of influenza virus that caused the 1918 global epidemic
("pandemic") was exceptionally aggressive. It showed a high capacity to cause
severe disease and a propensity to kill fit young adults rather than the
elderly. The mortality rate among the infected was over 2.5%, as compared to
less than 0.1% in other influenza epidemics (Taubenberger et al. 1997). This
high mortality rate, especially amongst the younger, lowered the average life
expectancy in the USA by almost 10 years (Tumpey et al. 2002). Creation of
this particularly dangerous influenza strain, as it is currently pursued by a
US research team, may thus pose a serious biowarfare threat.
A recent commentary in the Journal of the Royal Society of Medicine (Madjid et
al. 2003) noted that influenza is readily transmissible by aerosol and that a
small number of viruses can cause a full-blown infection. The authors
continued: "the possibility for genetic engineering and aerosol transmission
[of influenza] suggests an enormous potential for bioterrorism" The possible
hostile abuse of influenza virus is seen as a very real threat by public
health officials in the USA. Just two weeks ago, $15 million was granted by
the US National Institutes of Health to Stanford University to study how to
guard against the flu virus "if it were to be unleashed as an agent of
bioterrorism".[1]
US scientists led by a Pentagon pathologist recently began to genetically
reconstruct this specifically dangerous 1918 influenza strain. In one
experiment a partially reconstructed 1918 virus killed mice, while virus
constructs with genes from a contemporary flu virus had hardly any effect.
Attempts to recover the Spanish flu virus date to the 1950s, when scientists
unsuccessfully tried to revive the virus from victims buried in the permafrost
of Alaska.[2] In the mid 1990s, Dr Jeffrey Taubenberger from the US Armed
Forces Institute of Pathology started to screen preserved tissue samples from
1918 influenza victims. It appears that this work was not triggered by a
search for flu treatments, or the search for a new biowarfare agent, but by a
rather simple motivation: Taubenberger and his team were just able to do it.
In previous experiments they had developed a new technique to analyse DNA in
old, preserved tissues and for now looking for new applications: "The 1918 flu
was by far and away the most interesting thing we could think of"[3] explained
Taubenberger the reason why he started to unravel the secrets of one of most
deadliest viruses known to humankind.
A sample of lung tissue from a 21-year-old soldier who died in 1918 at Fort
Jackson in South Carolina[4], yielded what the Army researchers were looking
for: intact pieces of viral RNA that could be analysed and sequenced. In a
first publication in 1997, nine short fragments of Spanish flu viral RNA were
revealed (Taubenberger et al. 1997). Due to the rough tissue preparation
procedure in 1918, no living virus or complete viral RNA sequences were
recovered.
Genetic techniques helped to isolate more Spanish flu RNA from a variety of
sources. By 2002, four of the eight viral RNA segments had been completely
sequenced, including the two segments that are considered to be of greatest
importance for the virulence of the virus: the genes for hemagglutinin (HA)
and neuraminidase (NA). In the forthcoming issue of the scientific journal
Emerging Infectious Diseases, another article on the Spanish flu DNA sequence
will be published (Reid et al. 2003).
The project did not stop at sequencing the genome of the deadly 1918 strain.
The Armed Forces Institute of Pathology teamed up with a microbiologist from
the Mount Sinai School of Medicine in New York. Together, they started to
reconstruct the Spanish flu. In a first attempt, they combined gene fragments
from a standard laboratory influenza strain with one 1918 gene.[5] They
infected mice with this chimera, and it turned out that the 1918 gene made the
virus less dangerous for mice (Basler et al. 2001).[6]
In a second experiment, published in October 2002 (Tumpey et al. 2002), the
scientists were successful in creating a virus with two 1918 genes. This virus
was much more deadly to mice than other constructs containing genes from
contemporary influenza virus[7]. This experiment is only one step away from
taking the 1918 demon entirely out of the bottle and bringing the Spanish flu
back to life.
The scientists were aware of the dangers of their creation. The experiments
were conducted under high biosafety conditions at a laboratory of the US
Department of Agriculture in Athens, Georgia. Possible hostile use of their
work was an issue considered by the scientists:"the available molecular
techniques could be used for the purpose of bioterrorism" (Tumpey et al.
2002:13849).
There is no sound scientific reason to conduct these experiments. The most
recent experiments (Tumpey et al. 2002) allegedly seeked to test the efficacy
of existing antiviral drugs on the 1918 construct – but there is little need
for antiviral drugs against the 1918 strain if the 1918 strain would not have
been sequenced and recreated in the first place. It is true that biodefense
research – and any kind of civilian medical research – is always a race with
its counterpart, the evolution of naturally occuring infectious agents or the
development of biowarfare agents. But in this race it should be avoided to
create the threats that are allegedly the motivation for the research. A
vicious circle is created: "The technologies are in place with reverse
genetics to generate any influenza virus we wish ... studies are envisaged
using genes of the 1918 Spanish Influenza virus."[8] These arguments were
recently brought forward to justify another maximum biosafety laboratory for
biological defense work in Texas. Without Taubenberger’s pioneering work, the
money for the lab experiments might have been saved and better invested in
combating naturally occurring diseases such as tuberculosis, malaria, or HIV.
Other papers argued that the experiments may help to elucidate the mechanisms
of influenza evolution and virulence (Taubenberger et al. 1997, Basler et al.
2001), but this argument is also deeply flawed. Since 1918, a many different
influenza viruses with different virulence and pathogenicity properties have
been isolated and characterised by researchers around the world - a more than
abundant source for generations of scientists to study influenza evolution and
virulence. A resuscitation of the Spanish flu is neither necessary nor
warranted from a public health point of view.
There may be many reasons for the individual scientists to work on this
project, not least the scientific prestige - the" Spanish flu" subject matter
practically guaranteed a series of publications in prestigious journals. From
an arms control perspective it appears to be particularly sensitive if a
military research institution embarks on a project that aims at constructing
more dangerous pathogens - if Jeffery Taubenberger worked in a Chinese,
Russian or Iranian laboratory, his work might well be seen as the "smoking
gun" of a biowarfare program.
References
Basler CF, Reid AH, Dybing JK, Janczewski TA, Fanning TG, Zheng HY, Salvatore
M, Perdue ML, Swayne DE, García-Sastre A, Palese P, Taubenberger JK (2001)
Sequence of the 1918 pandemic influenza virus nonstructural gene (NS) segment
and characterization of recombinant viruses bearing the 1918 NS genes. PNAS
98:2746-2751
Madjid M, Lillibridge S, Mirhaji P, Casscells W (2003) Influenza as a
bioweapon. J Roy Soc Med 96:345-346
Reid AH, Janczewski TA, Raina M. Lourens RM, Elliot AJ, Rod S, CL Berry, JS
Oxford, JK Taubenberger (2003) 1918 Influenza pandemic caused by highly
conserved viruses with two receptor-binding variants. Emerg Infect Dis [serial
online] October 2003, available from: http://www.cdc.gov/ncidod/EID/vol9no10/02-0789.htm
Reid A, Fanning TG, Janczewski TA, McCall S, Taubenberger JK (2002)
Characterization of the 1918 "Spanish" Influenza Virus Matrix Gene Segment. J
Virol 76:10717-10723
Taubenberger JK, Reid AH, Krafft AE, Bijwaard KE, Fanning TG (1997) Initial
genetic characterization of the 1918 ‘Spanish’ influenza virus. Science
275:1793-1796
Tumpey TM, Garcia-Sastre A, Mikulasova A, Taubenberger JK, Swayne DE, Palese
P, Basler CF (2002) Existing antivirals are effective against influenza
viruses with genes from the 1918 pandemic virus. PNAS 99:13849-13854
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[1] Stanford University News Release 17 September 2003, online at http://mednews.stanford.edu/news_releases_html/2003/septrelease/bioterror%20flu.htm
[2] Spanish flu keeps its secrets. Nature science update at www.nature.com/nsu/990304/990304-5.html
[3] Profile: Jeffery Taubenberger at www.microbeworld.org/htm/aboutmicro/what_m_do/profiles/taubenberger.htm
[4] AFIP scientists discover clues to 1918 Spanish flu, www.dcmilitary.com/army/stripe/archives/mar28/str_flu032897.html
[5] The so called "nonstructural" gene (NS)
[6] It should be noted that for this experiments, a standard influenza strain
was used that was specifically adapted to mice and that was lethal to mice.
The scientists reasoned that the 1918 gene probably weakened the lethality for
the mice as it stemmed from a human-adapted strain.
[7] This time, the 1918 genes for hemagglutinin (HA), neuraminidase (NA) and
matrix (M) were used, single and in combination. Only the combination of the
1918 HA and NA genes caused a dramatic increase in lethality if compared to
constructs containing genes from a more recent human influenza virus. The
scientists concluded: "These data suggest that the 1918 HA and NA genes might
possess intrinsic high-virulence properties." (Tumpey et al. 2002:13853)
[8] Letter (4 February 2003) from Robert G. Webster, Professor of Virology at
St. Jude Children's Research Hospital to Stanley Lemon, Dean, School of
Medicine, University of Texas Medical Branch (UTMB) at Galveston, in support
of the UTMB application to contruct a National Biocontainment Laboratory.
Released to the Sunshine Project under the Texas Public Information Act
http://www.sunshine-project.org/publications/others/gmoflu.html