Q: My impression after watching NOVA's program "Bioterror" is that the U.S. is
largely responsible for the proliferation of potentially deadly agents
worldwide through private sector market outlets. What do you think the
domestic, political, and legal implications will be if it is proven that
international terrorists are purchasing materials from businesses and agencies
right here at home?
A: The challenge in preventing the spread of biological weapons is that most of
the necessary materials and production equipment are "dual-use," meaning that
they have legitimate commercial applications as well as potential military
uses. This fact makes the relevant technology extremely difficult to keep out
of the wrong hands. Nevertheless, the United States is a member of the
Australia Group, an informal forum of 33 industrialized countries that seek to
harmonize their national controls on exports of dual-use materials and
equipment to countries believed to be pursuing chemical and/or biological
Q: In the program it was mentioned that Bacillus anthracis is very
similar to Bacillus thurengensis, the active agent in some GMO corn. Is
it possible that terrorists could use the same technology to genetically modify
crops to produce anthrax to be carried in their pollen and other plant parts?
Has the corn genome been mapped well enough to know where to look if such was
A: Even if terrorists had the technical sophistication to incorporate genes for
anthrax toxins into genetically modified corn, which is unlikely, they would
have little reason to do so. Cooking would presumably inactivate the protein
toxins. Even if it did not, the ingestion of contaminated food would result in
gastrointestinal anthrax, which is considerably less deadly than the
inhalational form of the disease.
Q: For about the last two weeks I have been opening my mail out of doors and
disposing of the envelopes in a trash container outside of my home. Once having
opened my mail I wash my hands. I have been doing this to reduce possible
exposure to residual traces of anthrax that could be passed by cross
contamination in the postal
system. Is this a prudent precaution to take until irradiation of postal
content becomes commonplace? Thank you.
A: Although there is no harm in taking reasonable precautions when handling
mail, the risk that letters sent to your home in Michigan could be
cross-contaminated with anthrax spores is extremely low. To date, all of the
anthrax-tainted letters were sent to prominent individuals in politics or the
media, and only postal workers in New York, New Jersey, and Washington, D.C.
have been exposed by cross-contamination. (The one exception is the mysterious
case of inhalation anthrax in New York, which does not appear to have involved
exposure to mail.)
Q: I understand that the U.S. government keeps tight security on its chemical
and biological weapons, but what about foreign powers like the former Soviet
Union? Do they have the security necessary to keep the weapons out of terrorist
hands or from having them sold to the terrorists to pay for the country's
A: The U.S. government is concerned about the physical security of chemical
weapons and biological pathogens stored in former Soviet states, such as
Russia, Kazakhstan, and Uzbekistan. Although the Pentagon is providing
assistance to these countries to upgrade their security measures, much more
needs to be done.
Q: What exactly does it mean to "weaponize" a biological agent. How do
weaponized and nonweaponized anthrax differ?
If the terrorists in the recent anthrax attack wanted to maximize the loss of
life in our population, what prevented them from using some sort of aerosol to
spread the anthrax spores over a wider area than a mail room?
A: "Weaponization" refers to a variety of activities aimed at rendering a
biological pathogen more virulent, enhancing its stability and shelf-life, and
processing it so that it can be more readily delivered as a fine-particle
aerosol capable of infecting the targeted population through the air.
Non-weaponized anthrax would be in the vegetative (non-spore) form, which would
die off rapidly after dispersal. Weaponized anthrax would be in the spore form
and probably dried and milled to a fine powder, with chemicals added to reduce
clumping and to enhance aerosolization. It is possible that the perpetrators of
the recent anthrax attacks had only a few grams of weaponized anthrax, making
delivery through the mail the only practical means of delivery. Alternative
explanations are that they do not want to kill indiscriminately but simply to
terrorize the U.S. population, or that they plan to escalate gradually to more
Q: I first saw the movie "The Andromeda Strain" when just a kid in the '70s,
and I have always wondered if the book/movie has any basis in fact. Has our
government or other world governments sought out space-born biological agents?
Also, do we have "Wildfire" facilities to combat new disease organisms?
A: Michael Crichton's novel The Andromeda Strain appears to have no
basis in historical fact. Nevertheless, the Centers for Disease Control and
Prevention (CDC) in Atlanta and the U.S. Army Medical Research Institute of
Infectious Diseases (USAMRIID) at Fort Detrick, Maryland, do have
maximum-containment (Biosafety Level 4) laboratories for working with deadly
pathogens that resemble the "Wildfire" facility portrayed in the book.
Q: This may be a microbiologist question: If a bacteria or viral germ can
mutate to become contagious via the host by acquiring the genetic makeup, then
why could it not be a realistic possibility that anthrax or other such agents
that can become infectious through microbes also mutate to become contagious?
Also, how unlikely would it be for "terrorists" or groupings of them already in
the United States in various employment positions to taint our supplies of
food, water, etc. (such as individuals working on-site at large factories that
would have direct access to processing, packaging, or bottling facilities) with
anthrax or other viral/bacterial/chemical toxic agents?
A: I am not a microbiologist, but it appears to me extremely unlikely that a
non-contagious agent could mutate spontaneously into a contagious one. The
reason is that multiple genes are involved in the transmissibility of a
disease. As for contamination of water or food supplies with a biological
agent, the former is unlikely because of the combined effects of dilution,
chlorination, and filtration in water treatment plants. Food contamination
could be a problem, however, particularly at large plants that process
hamburger meat. For this reason, the U.S. government should substantially
increase the number of inspectors for meat and produce while consolidating the
various agencies with overlapping food-inspection responsibilities.
Q: In the offices and post offices where anthrax was found, is it possible that
some of the substance went home with people on their clothes, in their lunch
bags, etc.? If that happened, can the anthrax find a place to multiply, such as
in the soil of house plants? If someone unknowingly brought home a very small
amount from a contaminated site before the anthrax was discovered there, can
his or her home or car be a place where the anthrax can increase? Could it
later cause illness in family members and pets?
Chris Boston, MA
A: Small numbers of anthrax spores that were carried home on a person's clothes
would not germinate or multiply spontaneously. They could, however, cause a
cutaneous anthrax infection if an individual came in direct contact with the
spores and had a cut or abrasion on the skin.
Q: The NOVA program mentioned that both the U.S. and USSR had developed
agricultural weapons for purposes of disrupting economies. Is there any
evidence suggesting that an attack (w/foot and mouth, BSE, VEE, or others) on
our food supply could be a future move of any group?
A: The U.S. Department of Agriculture is very concerned about the possibility
that terrorists could deliberately release an anti-crop or anti-livestock agent
as a means of harming the U.S. economy. For example, an outbreak of
foot-and-mouth disease would be devastating for cattle ranchers and meat
Q: I noticed that the detection time for B. anthracis (airborne form) is
about four to seven days and that by that time the person with the infection is
too far along for antibiotics to help. If that's true, is anyone working to
find a quicker method of detection? After all, it seems as though the first 24
to 48 hours is crucial after inital contact with this particular
A: More rapid methods exist for detecting the presence of anthrax bacteria, but
they are prone to false-positive results. For this reason, all initial
detections must be confirmed by culturing the bacteria, which can take several
Q: I am very suspicious that AIDS was a product of experiments to modify
viruses for bioterror. Did it ever occur to people studying the disease that we
didn't have such a disease until the same era that Sergei Popov and others
(including Americans, to be fair to him) were involved with "genetic tweaking?"
The Australian government used such a sexually transmitted disease to eliminate
rabbits from the entire continent. What is the probability of statistics that
such a disease would come into being on its own or cross over from one species
A: Absolutely no evidence suggests that the HIV/AIDS virus was developed as a
biological warfare agent. In fact, the virus would make an exceedingly poor
weapon because it generally takes about a decade to cause serious illness. It
is certainly possible that HIV/AIDS originated as a disease of monkeys that
jumped the species barriers to humans. Indeed, many so-called "zoonotic"
pathogens cause illness in both animals and people.
Q: What is the difference between Pasternella pestis and Yersia
pestis? How many people in the U.S. and how many people in the world die
from bubonic plague? Is there an antidote? Is there an inoculation against it?
A:Pasteurella pestis is the old name for Yersinia pestis
(bubonic plague). According to the U.S. Centers for Disease Control and
Prevention, the last epidemic of plague in the United States took place in Los
Angeles in 1924-25. Since then, scattered cases of human plague have occurred
in rural areas, with an average of 10 to 15 cases per year. The disease is
endemic in wild rodents in parts of the western United States (the Four Corners
region, California, and Nevada) and occasionally spreads to humans, sometimes
via domestic cats that hunt infected rodents. Plague is also present in parts
of Africa, Asia, and South America. Worldwide, the World Health Organization
reports 1,000 to 3,000 cases of plague each year.
Q: I am a 10th grader in high school , and I am doing a report on bioterrorism.
An email from you answering some of my questions would greatly aid my grade.
Plus it would cure some of my curiosity.
People are taking medicine to protect them from anthrax and smallpox. If
they get one of these diseases, and they already took the medicine, wouldn't
the germs just mutate and eventually become immune to the medicines?
What would be the targets if the terrorists would have gotten hold of some
germs? (I live in Lockport, a small town south of Chicago, 35 miles away.)
Would it be possible to drop the germs on the south side of Chicago, and some
would actually cover my town?
I heard that anthrax is more deadly and cheaper than nuclear warheads. Is
If you have any really vital information about germ warfare or some astonishing
fact, it would be greatly appreciated. Thank you in advance.
A: (1) People who have not been exposed to anthrax should not self-administer
antibiotics such as Cipro for two reasons: the risk of serious side-effects,
and the fact that inappropriate use of antibiotics will hasten the evolution of
antibiotic-resistant strains of anthrax and other bacteria, making these
life-saving drugs ineffective when they are really needed. (2) Large quantities
(kilograms) of dried anthrax spores would have to be disseminated into the air,
probably from an aircraft, to cover an urban area. Depending on the method of
dissemination, the time of day, and the weather and atmospheric conditions, a
light wind might carry the "plume" of aerosolized anthrax several miles
downwind. (3) If roughly 100 kilograms of anthrax spores were disseminated over
a densely populated city under optimal weather and atmospheric conditions, and
the resulting cases of inhalation anthrax were left untreated, they could
potentially kill as many people as an atomic bomb. Because an anthrax weapon
would be much cheaper than a nuclear device, biological weapons have been
termed "the poor man's atom bomb."
Q: I don't believe any longer that this anthrax problem in the U.S. was the act
of a "loner." I believe it was the act of a well-organized group. Well, anyway
since we now know that bioterriorists have anthrax as a potential weapon, what
are the other possible deadly "bioattacks" that could occur? What is your best
guess as to what will be the next bioattack?
Also, what do you recommend that "ordinary" people have in their medical
supplies at home? What is the best and least expensive informational source and
possibly free places where one can get up-to-date pamphlets etc.?
Glen Burnie, MD
A: It seems hard to imagine that an individual working alone would have the
know-how and resources to acquire or produce the high-grade anthrax used in the
letter attacks. What the perpetrator(s) will do next depends on their
motivations and their technical capabilities, which remain unknown. Thus, we
must be prepared for a range of contingencies. Accurate scientific information
on bioterrorism is available from the Web site of the U.S. Centers for Disease
Control and Prevention at the following address: http://www.bt.cdc.gov
Q: What is the real danger to the American public from airborne and waterborne
A: In addition to the threat of bioterrorism, a variety of natural infectious
disease agents threaten the health of U.S. citizens. A subset of these
pathogens are transmissible through the air (e.g., measles, influenza) or water
(e.g., E. coli, Shigella, Giardia).
Q: I am particularily interested in a concept that was introduced during the
last NOVA broadcast. The concept explained that it is currently possible
through the melting of DNA, that DNA from myelin-producing cells can be
attached within plasmids of certain infectious bacteria such as pneumococcus.
The condition created is one in which the host's body will overcome the
bacteria but then turn its immunoresponse to its own myelin, therefore killing
the host by destroying its neurological system.
To your knowledge, has this been done, and what is the process at the DNA
level? The reason for my question is that I am currently working towards a
masters of science and in one of my classes we used PCR to melt and study DNA.
I wondered if the processes learned in an intermediate class could be used to
A: Recombinant DNA technologies, such as those taught in your class, could
potentially be used to develop more deadly pathogens for malicious purposes,
although doing so would require a high level of expertise as well as
considerable trial and effort. Molecular biologists need to be aware of the
potential misuse of these powerful technologies and to do everything in their
power to prevent it.