by Col. Byron Weeks, M.D., Ret.
Monday, Oct. 15, 2001
Weeks has had a distinguished medical and military
career with the U.S. Air Force Medical Corps. Dr.
Weeks began military service as the youngest flight
surgeon in the U.S. Air Force during the Korean War.
After 15 years of military service, during which he
served in senior posts, including Hospital Commander at
Bitburg Air Force Base, Germany, Dr. Weeks retired and
entered private practice. During the past two decades,
he has focused his studies on the threat of biological
and chemical agents as weapons of war. Dr. Weeks
has lectured and written numerous articles on infectious
diseases and biological warfare.
Anthrax poses a significant threat to Americans and should not be
dismissed as an ineffective bio-weapon, as many media are portraying
it. Bacillus anthracis, the causative agent of anthrax, is a
Gram-positive, spore-forming rod. The spores are the usual infective
form. Anthrax is primarily a zoonotic (communicable from animals to
humans) disease of herbivores, with cattle, sheep, goats and horses
being the usual domesticated animal hosts, but other animals may be
Humans generally contract the disease when handling contaminated
hair, wool, hides, flesh, blood and excreta of infected animals and
from manufactured products such as bone meal. Infection is
introduced through scratches, abrasions and wounds, or by inhaling
spores, eating insufficiently cooked infected meat, or being bitten
The primary concern for intentional infection by this organism is
through inhalation after aerosol dissemination of spores. All human
populations are susceptible. The spores are very stable and may
remain viable for many years in soil and water. They resist sunlight
for varying periods.
Anthrax spores were weaponized by the United States in the 1950s and
1960s, before the old U.S. offensive program was terminated. Other
countries have weaponized this agent or are suspected of doing so.
Anthrax bacteria are easy to cultivate and spore production is
readily induced. Moreover, the spores are highly resistant to
sunlight, heat and disinfectants – properties which could be
advantageous when choosing a bacterial weapon.
Weaponized spores are heartier than ones that Western medical
experts have seen before; therefore, the risk from these spores is
greater than many may believe. Iraq admitted to a United Nations
inspection team in August of 1991 that it had performed research on
the offensive use of B. anthracis prior to the Persian Gulf War, and
in 1995 Iraq admitted to weaponizing anthrax. Dr. Ken Alibek, a
recent defector from the former Soviet Union's biological weapons
program, revealed that the Soviets had produced anthrax in ton
quantities for use as a weapon.
This agent could be produced in either a wet or dried form. Coverage
of a large ground area could theoretically be facilitated by
multiple spray bomblets containing desiccated spores disseminated
from a missile warhead at a predetermined height above the ground.
Anthrax presents as three somewhat distinct clinical syndromes in
form (also referred to as a malignant pustule) occurs most
frequently on the hands and forearms of persons working with
infected livestock. It begins as a papule (bump) followed by
formation of a fluid-filled vesicle (blister). The vesicle typically
dries and forms a coal-black scab (eschar); hence, the term
(from the Greek for coal). This local infection can occasionally
disseminate into a fatal systemic infection.
Gastrointestinal anthrax is rare in humans, and is contracted by the
ingestion of insufficiently cooked meat from infected animals. Endemic
inhalational anthrax, known as woolsorter's disease,
is also a rare infection, contracted by inhalation of the spores. It
occurs mainly among workers in industrial settings who handle
infected hides, wool and furs. Inhalational anthrax usually has an
incubation period of 1-6 days, although in an outbreak in Sverdlovsk
in the Soviet Union, one patient had a six-week interval between
exposure and onset. [See note at end for more on outbreak.]
Because the number of spores needed to kill an animal from
inhalational anthrax is much smaller than for a human, animals will
be the first to shows symptoms of the disease and die. Thus, the
unusual incidence of deaths of dogs, cats and other pets may serve
as an early warning of an anthrax outbreak. In humans, the mortality
of untreated cutaneous anthrax ranges up to 25 percent; in
inhalational and intestinal cases, the case fatality rate is 90
percent to 100 percent.
After an incubation period of 1-6 days, presumably dependent upon
the strain and number of organisms inhaled, the onset of
inhalational anthrax is gradual and nonspecific.
Fever, malaise and fatigue may be present, sometimes in association
with a nonproductive cough and mild chest discomfort. These initial
symptoms are often followed by a short period of improvement (from
hours to 2-3 days), followed by the abrupt development of severe
respiratory distress with sweating, shortness of breath, stridor
(sound of respiration when airways are obstructed) and cyanosis
(bluish color of skin due to insufficient oxygen in blood).
Septicemia (blood poisoning), shock and death usually follow within
24-36 hours after the onset of respiratory distress. Physical
findings are typically non-specific, especially in the early phase
of the disease. The chest X-ray often reveals a widened mediastinum
(chest cavity) with or without pleural effusions late in the disease
in about 55 percent of the cases, but typically is without lung
infiltrates. Pneumonia generally does not occur; therefore,
organisms are not typically seen in the sputum. Bacillus anthracis
will be detectable by Gram stain of the blood and by blood culture
with routine media, but often not until late in the course of the
Approximately 50 percent of cases are accompanied by hemorrhagic
meningitis, and therefore organisms may also be identified in
cerebrospinal fluid. Only vegetative encapsulated bacilli are
present during infection; spores are not found within the body
unless it is opened to ambient air.
Bacilli and toxin appear in the blood late on day 2 or early on day
3 post-exposure. Toxin production parallels the appearance of
bacilli in the blood and tests are available to rapidly detect the
toxin. Concurrently with the appearance of anthrax, the WBC (white
blood cell) count becomes elevated and remains so until death.
Almost all inhalational anthrax cases in which treatment was begun
after patients were significantly symptomatic have been fatal,
regardless of treatment. Penicillin has been regarded as the
treatment of choice, with 2 million units given intravenously every
2 hours. Tetracyclines and erythromycin have been recommended in
The vast majority of naturally occurring anthrax strains are
sensitive to penicillin in vitro (in the laboratory). However,
Russia has developed new strains that are resistant to penicillin,
tetracyclines, erythromycin and probably other antibiotics, through
laboratory manipulation of organisms. All naturally occurring
strains tested to date have been sensitive to erythromycin,
chloramphenicol, gentamicin, and ciprofloxacin (cipro).
In the absence of antibiotic sensitivity data, empiric intravenous
antibiotic treatment should be instituted with cipro at a dose of
400-800 mg IV twice daily at the earliest signs of disease.
U.S. military policy (FM 8-284) currently recommends ciprofloxacin
(400 mg IV every 12 hours) or doxycycline (200 mg IV load, followed
by 100 mg IV every 12 hours) as initial therapy, with penicillin (4
million units IV every 4 hours) as an alternative once sensitivity
data is available.
Published recommendations from a public health consensus panel
recommends ciprofloxacin as initial therapy. Recommended treatment
duration of the active case is 60 days, and should be changed to
oral therapy as clinical condition improves. Supportive therapy for
shock, fluid volume deficit and inadequacy of airway may all be
needed. Standard precautions are recommended for patient care. There
is no evidence of direct person-to-person spread of disease from
After an invasive procedure or autopsy, the instruments and area
used should be thoroughly disinfected with a sporicidal
(spore-killing) agent such as formaldehyde. Sodium or calcium
hypochlorite can be used, but with the caution that the activity of
hypochlorites is greatly reduced in the presence of organic
Vaccine: A licensed vaccine (Anthrax Vaccine Adsorbed) made
solely by BioPort Corp. is derived from sterile culture fluid
supernatant taken from an attenuated strain. Therefore, the vaccine
does not contain live or dead organisms. However, because of
numerous severe immunologic reactions to this vaccine, I cannot
Antibiotics: Both military doctrine and a public health
consensus panel recommend prophylaxis with ciprofloxacin (500 mg
orally twice a day) as the first-line medication in a situation with
anthrax as the presumptive agent. Ciprofloxacin recently became the
first medication approved by the FDA for prophylaxis after exposure
to a biological weapon (anthrax).
Bioweaponized anthrax is very likely to be resistant to alternatives
such as doxycycline (100 mg orally twice a day) or amoxicillin
(500mg orally every 8 hours). Should an attack be confirmed as
anthrax, antibiotics should be continued for at least 4 weeks in all
those exposed. Optimally, patients should have medical care
available upon discontinuation of antibiotics, from a fixed medical
care facility with intensive care capabilities and infectious
"Biohazard" by Ken Alibek, M.D.,
USAMRIID: Manual of Biological
In April 1979, an anthrax outbreak in the Soviet city of
Sverdlovsk, roughly 850 miles east of Moscow, killed 66 of
94 infected people. The first victim died after 4 days; the
last one died 6 weeks later.
The Soviet government claimed the deaths were caused by
intestinal anthrax from tainted meat. It was not until 1992
that President Boris Yeltsin admitted the outbreak was the
result of military activity at a suspected Soviet biological
weapons facility located in the city.