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Science
Friday > Archives
> 1999
> April
> April 2, 1999:
Hour One: The Fate of Smallpox / "Melissa" Virus
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Almost twenty years ago, the World Health
Assembly declared the human population free of
smallpox - but the virus has lived on, sleeping in
freezers in two labs in the US and Moscow. On June
30th, the remaining stores of the virus are
scheduled to be destroyed, baked into oblivion
inside an autoclave. But experts are still debating
whether or not that's a good idea.
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Image courtesy CDC
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Some scientists say that there are valid scientific
reasons for preserving the virus, including the information
it might provide about immunity and infection. Smallpox is
believed to use several unusual tricks to sidestep immune
defenses. Without access to the virus, they claim, knowledge
about those tricks could be lost - and that knowledge could
be used to help fight other diseases. Some researchers think
that the tricks smallpox uses to hide from the immune system
could also be used to prevent rejection of organ
transplants.
Others feel that all stockpiles of the virus should be
eliminated, saying destruction of the virus will make it
more difficult for bioterrorists to develop weapons. In
addition, they argue, most of the information available from
the virus has already been extracted - or can be obtained
without need for the live virus. And both sides of the
debate agree that there are probably other sources of the
virus than the two "official" repositories - rogue labs,
possible animal sources, and tissues from the bodies of
infected people.
What are the pros and cons of saving the remaining smallpox samples...
and what do YOU think? Talk about it on this segment of Science Friday.
Plus...
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Last Friday, word began to spread about a new kind of computer
virus called "Melissa" (or, more technically, W97M/Melissa). And
the virus began to spread, too - affecting thousands of computer
users and clogging email servers at several large corporations.
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As you've probably heard by now, if you get a piece of e-mail with a Microsoft
Word document attached, you should use extreme caution in opening it.
The Melissa virus uses a macro programming language built into Microsoft
Office to open up the address books of infected machines and send itself
out to the first fifty entries in each address book. It also changes the
base template for all future Word documents created on that machine -
so any letter or report written on that machine afterwards will contain
the virus. If that document is later opened on an uninfected machine,
the process will start again (potentially sending your letter to Aunt
Minnie to 50 of her friends, too!)
The virus depends on several widely-used pieces of Microsoft software,
Word and Outlook, to survive and spread. But it also depends on users
turning off security features to allow Word to open the infected documents.
Variants of the virus have been appearing as well. One, called Papa,
uses similar principles to infect Excel documents. Others use Melissa
code but tweak it a little, using different subject lines to try to
step around efforts to block the virus.
On this segment of Science Friday, we'll talk about how the virus has
been spreading, and about efforts to track down its creator through
identifying marks left in the viral code itself.
Guests:
D.A. Henderson
Professor, Epidemiology
Director,
Center for
Civilian Biodefense
Johns Hopkins
University
Baltimore, Maryland
R. Palmer Beasley
Professor, Epidemiology
Dean, School of Public Health
University of Texas-Houston Health
Science Center
Houston, Texas
Eric Allman
Chief Technical Officer
Sendmail, Inc
Books/Articles Discussed:
Related Links:
Immunization
Practices Advisory Committee: Smallpox
"Lessons
Learned from the Eradication of Smallpox"
Epidemics:
Smallpox
Centers for Disease Control
World Health Organization
CERT
advisory
Microsoft
advisory
ZDNet
Coverage
This segment produced by:
Annette Heist
Web producer:
Charles Bergquist
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