Early detection
of and response to a bioterrorist attack are crucial to
decrease illness and deaths, especially in the event of a
covert attack with a biologic agent. In all reality any
disease or bacteria agent can be used as a biological agent,
however difficulty in delivering the agent in a widespread
manner limits the choices of terrorists. Below are the agents
that have been developed and are most likely agents used in a
possible atack. Along with smallpox, anthrax, plague,
botulism, and tularemia, hemorrhagic fever viruses are among
the six agents identified by the Centers for Disease Control
and Prevention as the most likely to be used as biological
weapons.
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Bioterrorism : Main Agents and Diseases: |
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Anthrax |
| a
serious disease caused by
Bacillus anthracis,
a bacterium that forms spores. A bacterium is a very
small organism made up of one cell. Many bacteria can
cause disease. A spore is a cell that is dormant
(asleep) but may come to life with the right
conditions. |
There
are three types of anthrax:
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skin (cutaneous)
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lungs (inhalation)
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digestive
(gastrointestinal)
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Anthrax
is not known to spread from one person to another |
| Anthrax
also can be used as a weapon. This happened in the
United States in 2001. Anthrax was deliberately spread
through the postal system by sending letters with
powder containing anthrax. This caused 22 cases of
anthrax infection. |
What Are the
Symptoms?
The symptoms (warning
signs) of anthrax are different depending on the type
of the disease:
- Cutaneous: The
first symptom is a small sore that develops into a
blister. The blister then develops into a skin ulcer
with a black area in the center. The sore, blister
and ulcer do not hurt.
- Gastrointestinal:
The first symptoms are nausea, loss of appetite,
bloody diarrhea, and fever, followed by bad stomach
pain.
- Inhalation: The
first symptoms of inhalation anthrax are like cold
or flu symptoms and can include a sore throat, mild
fever and muscle aches. Later symptoms include
cough, chest discomfort, shortness of breath,
tiredness and muscle aches. (Caution: Do not assume
that just because a person has cold or flu symptoms
that they have inhalation anthrax.)
Symptoms can appear
within 7 days of coming in contact with the bacterium
for all three types of anthrax. For inhalation
anthrax, symptoms can appear within a week or can take
up to 42 days to appear
How Is Anthrax Treated?
Antibiotics are
used to treat all three types of anthrax. Early
identification and treatment are important.
Prevention after
exposure.
Treatment is different for a person who is exposed to
anthrax, but is not yet sick. Health-care providers
will use antibiotics (such as ciprofloxacin,
levofloxacin, doxycycline, or penicillin) combined
with the anthrax vaccine to prevent anthrax
infection. Treatment after infection.
Treatment is usually a
60-day course of antibiotics. Success depends on the
type of anthrax and how soon treatment begins
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Plague |
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| Plague
is a disease caused by Yersinia pestis (Y. pestis), a
bacterium found in rodents and their fleas in many
areas around the world. |
| Yersinia
pestis used in an aerosol attack could cause cases of
the pneumonic form of plague. One to six days after
becoming infected with the bacteria, people would
develop pneumonic plague. Once people have the
disease, the bacteria can spread to others who have
close contact with them. Because of the delay between
being exposed to the bacteria and becoming sick,
people could travel over a large area before becoming
contagious and possibly infecting others. Controlling
the disease would then be more difficult. A bioweapon
carrying Y. pestis is possible because the bacterium
occurs in nature and could be isolated and grown in
quantity in a laboratory. Even so, manufacturing an
effective weapon using Y. pestis would require
advanced knowledge and technology. |
What are
the signs and symptoms of pneumonic plague?
Patients
usually have fever, weakness, and rapidly developing
pneumonia with shortness of breath, chest pain, cough,
and sometimes bloody or watery sputum. Nausea,
vomiting, and abdominal pain may also occur. Without
early treatment, pneumonic plague usually leads to
respiratory failure, shock, and rapid death. |
Can a person exposed to pneumonic plague avoid
becoming sick?
Yes. People who have had close contact with an
infected person can greatly reduce the chance of
becoming sick if they begin treatment within 7 days of
their exposure. Treatment consists of taking
antibiotics for at least 7 days. |
Can
pneumonic plague be treated?
Yes. To prevent a high risk of death,
antibiotics should be given within 24 hours of the
first symptoms. Several types of antibiotics are
effective for curing the disease and for preventing
it. Available oral medications are a tetracycline
(such as doxycycline) or a fluoroquinolone (such as
ciprofloxacin). For injection or intravenous use,
streptomycin or gentamicin antibiotics are used. Early
in the response to a bioterrorism attack, these drugs
would be tested to determine which is most effective
against the particular weapon that was used. |
How long can plague bacteria exist in the environment?
Yersinia pestis is easily destroyed by
sunlight and drying. Even so, when released into air,
the bacterium will survive for up to one hour,
depending on conditions |
What should someone do if they suspect they or others
have been exposed to plague?
Get immediate medical attention: To prevent
illness, a person who has been exposed to pneumonic
plague must receive antibiotic treatment without
delay. If an exposed person becomes ill, antibiotics
must be administered within 24 hours of their first
symptoms to reduce the risk of death. Notify
authorities: Immediately notify local or state health
departments so they can begin to investigate and
control the problem right away. If bioterrorism is
suspected, the health departments will notify the CDC,
FBI, and other appropriate authorities.
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| Botulism:
Video: "The History of Bioterrorism: Botulism" |
| Botulism is a muscle-paralyzing
disease caused by a toxin made by a bacterium called
Clostridium botulinum. |
There are three
main kinds of botulism:
- Food borne botulism
occurs when a person ingests pre-formed toxin that
leads to illness within a few hours to days.
Foodborne botulism is a public health emergency
because the contaminated food may still be available
to other persons besides the patient.
- Infant botulism
occurs in a small number of susceptible infants each
year who harbor C.
botulinum in their intestinal tract.
- Wound botulism
occurs when wounds are infected with
C. botulinum
that secretes the toxin.
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| With
food borne botulism, symptoms begin within 6 hours to
2 weeks (most commonly between 12 and 36 hours) after
eating food that contains the toxin. Symptoms of
botulism include double vision, blurred vision,
drooping eyelids, slurred speech, difficulty
swallowing, dry mouth, and muscle weakness that moves
down the body, always affecting the shoulders keep
descends first, then the upper arms, lower arms,
thighs, calves, etc. Paralysis of breathing muscles
can cause a person to stop breathing and die, unless
assistance with breathing (mechanical ventilation) is
provided |
| Botulism
is not spread from one person to another. Food borne
botulism can occur in all age groups. |
| A supply
of antitoxin against botulism is maintained by CDC.
The antitoxin is effective in reducing the severity of
symptoms if administered early in the course of the
disease. Most patients eventually recover after weeks
to months of supportive care. |
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Smallpox
Video: "The History of Bioterrorism : Smallpox" |
| Smallpox
is a serious, contagious, and sometimes fatal
infectious disease. There is no specific treatment for
smallpox disease, and the only prevention is
vaccination. The pox
part of smallpox
is derived from the Latin word for “spotted” and
refers to the raised bumps that appear on the face and
body of an infected person.
Is
smallpox fatal? The majority of patients with
smallpox recover, but death may occur in up to 30% of
cases. Many smallpox survivors have permanent scars
over large areas of their body, especially their face.
Some are left blind |
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Generally, direct and fairly prolonged face-to-face
contact is required to spread smallpox from one person
to another. Smallpox also can be spread through direct
contact with infected bodily fluids or contaminated
objects such as bedding or clothing. Rarely, smallpox
has been spread by virus carried in the air in
enclosed settings such as buildings, buses, and
trains. Humans are the only natural hosts of variola.
Smallpox is not known to be transmitted by insects or
animals. |
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Bioterrorism preparationsThere
are concerns that the smallpox virus could be used for
bioterrorism. The risk for smallpox occurring as a
result of a deliberate release by terrorists is not
known, but is considered very low. On May 8-9, 2002, a
joint working group consisting of members of the
Advisory Committee on Immunization Practices (ACIP)
and the National Vaccine Advisory Committee (NVAC),
two groups that provide recommendations to CDC and the
Department of Health and Human Services (DHHS) on
vaccine use and policies, met in Atlanta as part of
their review of the current smallpox vaccine
recommendations. This working group was convened to
review the June 2001 ACIP recommendations on smallpox
vaccination in light of recent events, including the
expected availability of about 286 million doses of
smallpox vaccine by the end of the year. As a result,
we now have in the stockpile, enough vaccine to
vaccinate every person in the United States.
If smallpox is released
in aerosol form, how long does the virus survive?
The smallpox
virus is fragile. In laboratory experiments, 90% of
aerosolized smallpox virus dies within 24 hours; in
the presence of ultraviolet (UV) light, this
percentage would be even greater. If an aerosol
release of smallpox occurs, 90% of virus matter will
be inactivated or dissipated in about 24 hours.
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Is there any treatment for smallpox?
Smallpox can be prevented through use of the smallpox
vaccine. There is no proven treatment for smallpox,
but research to evaluate new antiviral agents is
ongoing. Early results from laboratory studies suggest
that the drug cidofovir may fight against the smallpox
virus |
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Tularemia |
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Tularemia is a potentially serious illness that occurs
naturally in the United States. It is caused by the
bacterium Francisella
tularensis found in animals (especially rodents,
rabbits, and hares). |
What are the
Symptoms of Tularemia?
Symptoms of tularemia
could include:
- sudden fever
- chills
- headaches
- diarrhea
- muscle aches
- joint pain
- dry cough
- progressive
weakness
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How Does
Tularemia Spread?
People can get
tularemia many different ways:
- being bitten by an
infected tick, deerfly or other insect
- handling infected
animal carcasses
- eating or drinking
contaminated food or water
- breathing in the
bacteria, F.
tularensis
Tularemia is not known to be spread from person to
person
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How Is Tularemia Treated?
Your doctor will most
likely prescribe antibiotics, which must be taken
according to the directions supplied with your
prescription to ensure the best possible result. Let
your doctor know if you have any allergy to
antibiotics.
A vaccine for
tularemia is under review by the Food and Drug
Administration and is not currently available in the
United States.
Can Tularemia Be Used As a Weapon?
Francisella
tularensis is very infectious. A small number
(10-50 or so organisms) can cause disease. If
F. tularensis
were used as a weapon, the bacteria would likely be
made airborne for exposure by inhalation. People who
inhale an infectious aerosol would generally
experience severe respiratory illness, including
life-threatening pneumonia and systemic infection, if
they are not treated. The bacteria that cause
tularemia occur widely in nature and could be isolated
and grown in quantity in a laboratory, although
manufacturing an effective aerosol weapon would
require considerable sophistication. |
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Viral hemorrhagic fevers
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| Viral
hemorrhagic fevers (VHFs) are diseases caused by several
distinct viral families usually found in animals,
especially certain rats and mice, or insects, such as
ticks and mosquitoes. However, the origins of some viruses
are not yet known, such as the Ebola and Marburg viruses.
Viral hemorrhagic fevers
affect multiple organs in the body and range from mild to
life-threatening. The symptoms of viral hemorrhagic fevers
vary, but often include:
- Fever.
- Fatigue or exhaustion.
- Dizziness.
- Muscle aches.
- Weakness.
When the illness is
severe, symptoms may include bleeding (hemorrhage) under
the skin, in internal organs, or from body orifices such
as the mouth, eyes, or ears. Other symptoms of severe
illness include shock, coma, and seizures.
Although some treatments,
such as the antiviral drug ribavirin, may help relieve
some symptoms, no standard cure exists for viral
hemorrhagic fevers. In addition, vaccines are available
for only two strains of viral hemorrhagic fevers: yellow
fever and Argentine hemorrhagic fever. Avoiding contact
with the animals and insects known to carry viral
hemorrhagic fevers is the main form of protection |
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Related Web links
Biological Terrorism - General Guidance (2003)
Botulinum Toxin as a Biological Weapon: Medical and
Public Health Management |
