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IN OUR OCTOBER NEWSLETTER
WE FOCUS ON
What is anthrax?
Anthrax is an acute infectious disease caused by the spore-forming
bacterium Bacillus anthracis. Anthrax most commonly occurs in wild and
domestic lower vertebrates (cattle, sheep, goats, camels, antelopes, and
other herbivores), but it can also occur in humans when they are exposed
to infected animals or tissue from infected animals.
Why has anthrax become a current issue?
Because anthrax is considered to be a potential agent for use in biological
warfare, the Department of Defense (DoD) has begun mandatory
vaccination of all active duty military personnel who might be involved in
conflict.
How common is anthrax and who can get it?
Anthrax is most common in agricultural regions where it occurs in animals.
These include South and Central America, Southern and Eastern Europe,
Asia, Africa, the Caribbean, and the Middle East. When anthrax affects
humans, it is usually due to an occupational exposure to infected animals
or their products. Workers who are exposed to dead animals and animal
products from other countries where anthrax is more common may
become infected with B. anthracis (industrial anthrax). Anthrax in wild
livestock has occurred in the United States.
How is anthrax transmitted?
Anthrax infection can occur in three forms: cutaneous (skin), inhalation,
and gastrointestinal. B. anthracis spores can live in the soil for many years,
and humans can become infected with anthrax by handling products from
infected animals or by inhaling anthrax spores from contaminated animal
products. Anthrax can also be spread by eating undercooked meat from
infected animals. It is rare to find infected animals in the United States.
What are the symptoms of anthrax?
Symptoms of disease vary depending on how the disease was contracted,
but symptoms usually occur within 7 days.
Cutaneous:
Most (about 95%) anthrax infections occur when the
bacterium enters a cut or abrasion on the skin, such as when handling
contaminated wool, hides, leather or hair products (especially goat hair) of
infected animals. Skin infection begins as a raised itchy bump that
resembles an insect bite but within 1-2 days develops into a vesicle and
then a painless ulcer, usually 1-3 cm in diameter, with a characteristic
black necrotic (dying) area in the center. Lymph glands in the adjacent
area may swell. About 20% of untreated cases of cutaneous anthrax will
result in death. Deaths are rare with appropriate antimicrobial therapy.
Inhalation:
Initial symptoms may resemble a common cold. After
several days, the symptoms may progress to severe breathing problems
and shock. Inhalation anthrax is usually fatal.
Intestinal:
The intestinal disease form of anthrax may follow the
consumption of contaminated meat and is characterized by an acute
inflammation of the intestinal tract. Initial signs of nausea, loss of appetite,
vomiting, fever are followed by abdominal pain, vomiting of blood, and
severe diarrhea. Intestinal anthrax results in death in 25% to 60% of
cases.
Where is anthrax usually found?
Anthrax can be found globally. It is more common in developing countries
or countries without veterinary public health programs. Certain regions of
the world (South and Central America, Southern and Eastern Europe, Asia,
Africa, the Caribbean, and the Middle East) report more anthrax in
animals than others.
Can anthrax be spread from person-to-person?
Direct person-to-person spread of anthrax is extremely unlikely to occur.
Communicability is not a concern in managing or visiting with patients with
inhalational anthrax.
Is there a way to prevent infection?
In countries where anthrax is common and vaccination levels of animal
herds are low, humans should avoid contact with livestock and animal
products and avoid eating meat that has not been properly slaughtered
and cooked. Also, an anthrax vaccine has been licensed for use in humans.
The vaccine is reported to be 93% effective in protecting against anthrax.
What is the anthrax vaccine?
The anthrax vaccine is manufactured and distributed by BioPort,
Corporation, Lansing, Michigan. The vaccine is a cell-free filtrate vaccine,
which means it contains no dead or live bacteria in the preparation. The
final product contains no more than 2.4 mg of aluminum hydroxide as
adjuvant. Anthrax vaccines intended for animals should not be used in
humans.
Who should get vaccinated against anthrax?
The Advisory Committee on Immunization Practices has recommend
anthrax vaccination for the following groups:
Persons who work directly with the organism in the laboratory
Persons who work with imported animal hides or furs in areas where
standards are insufficient to prevent exposure to anthrax spores.
Persons who handle potentially infected animal products in
high-incidence areas. (Incidence is low in the United States, but
veterinarians who travel to work in other countries where incidence
is higher should consider being vaccinated.)
Military personnel deployed to areas with high risk for exposure to
the organism (as when it is used as a biological warfare weapon).
The anthrax Vaccine Immunization Program in the U.S. Army
Surgeon General's Office can be reached at 1-877-GETVACC
(1-877-438-8222). http://www.anthrax.osd.mil
Pregnant women should be vaccinated only if absolutely
necessary.
What is the protocol for anthrax vaccination?
The immunization consists of three subcutaneous injections given 2 weeks
apart followed by three additional subcutaneous injections given at 6, 12,
and 18 months. Annual booster injections of the vaccine are recommended
thereafter.
Are there adverse reactions to the anthrax vaccine?
Mild local reactions occur in 30% of recipients and consist of slight
tenderness and redness at the injection site. Severe local reactions are
infrequent and consist of extensive swelling of the forearm in addition to
the local reaction. Systemic reactions occur in fewer than 0.2% of
recipients.
How is anthrax diagnosed?
Anthrax is diagnosed by isolating B. anthracis from the blood, skin lesions,
or respiratory secretions or by measuring specific antibodies in the blood
of persons with suspected cases.
Is there a treatment for anthrax?
Doctors can prescribe effective antibiotics. To be effective, treatment
should be initiated early. If left untreated, the disease can be fatal.
Where can I get more information about the recent Department
of Defense decision to require men and women in
the Armed Services to be vaccinated against anthrax?
The Department of Defense recommends that servicemen and women
contact their chain of command on questions about the vaccine and its
distribution. The anthrax Vaccine Immunization Program in the U.S.
Army Surgeon General's Office can be reached at 1-877-GETVACC
(1-877-438-8222). http://www.anthrax.osd.mil
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Robert Koch
His original micrographs of
Anthrax Bacillus.
I am glad you are taking the time to educate yourself about anthrax. However,
there is a large
amount of hysteria about this illness because of recent events so I thought I
would share some
important points about anthrax.
1.
Anthrax is not contagious. The only way to get the disease is to be exposed
to spores of
the microbe.
2.
Not much will kill these spores. Microwaving, baking, and disinfectant have
no effect. If
you burn your mail, that will work, but then you can't read that letter from
Aunt Marge.
3.
Getting spores in an envelope is not a real threat. Anthrax spores need to
be dispersed in
the air with very advanced equipment to become the dangerous form, pulmonary
anthrax,
that is lethal. Since whoever is doing this is mailing the stuff, it's obvious
we are dealing with
amateurs who really don't understand what they are doing. In that you can take
some
comfort. If you do recieve a suspicious package report it to your local
authorities and
consult your physician. However, it will be very unlikely that you will recieve
one of these
letters. Think about how many pieces of mail go out and how many people there
are. Your
chances are very low.
4.
Cutaneous antrax only occurs when the spores encounter broken skin creating
an easily
recognized boil. Even then the illness is rarely fatal.
5.
Anthrax is easily treated with antibiotics if it is caught early enough.
The only time I would
be worried about this is if everyone around you is coming down with the flu at
the same
time. Believe me the government will be all over something like that and has a
stock pile of
antibiotics for such an occasion.
6.
You should not try to get vaccinated nor buy antibiotics just in case.
First, your chances of
contracting the disease are less than getting hit by lightning or winning the
lottery, so you
would be wasting your money. Second, you are depleting the stores of
antibiotics that are
available to treat people who may end up having the illness. Finally, the
antibiotics will go
bad over time and not be effective anyway. No responsible physician should be
filling
prescriptions to people who have not been exposed to anthrax, just in case. If
you find a
doctor willing to do this, can you trust them? What's to say that they are not
just selling you
sugar pills or something worse?
7.
The disease is caused by a bacterium not a virus as reported by some news
agencies. (By
the way some journalists are woefully ignorant of medicine and microbiology -
be careful
what you believe.)
The anthrax bacillus was the first bacterium shown to be the cause of a
disease. In 1877,
Robert Koch grew it in pure culture, demonstrated its ability to form
endospores, and produced
experimental anthrax by injecting it into animals.
Information Paper
Anthrax as a Biological Warfare Agent
Anthrax is the preferred biological warfare agent because:
It is highly lethal.
100 million lethal doses per gram of anthrax material (100,000 times deadlier
than the deadliest chemical warfare agent).
Silent, invisible killer.
Inhalational anthrax is virtually always fatal.
There are low barriers to production.
Low cost of producing the anthrax material.
Not high-technology. Knowledge is widely available.
Easy to produce in large quantities.
It is easy to weaponize.
It is extremely stable. It can be stored almost indefinitely as a dry powder.
It can be loaded, in a freeze-dried condition, in munitions or disseminated as
an
aerosol with crude sprayers.
Currently, we have a limited detection capability.
Humans can contract anthrax in three ways:
1.
Through cuts or breaks in the skin resulting from contact with an infected
animal (cutaneous anthrax), resulting in local and possibly systemic
(bloodstream) infection.
2.
From breathing anthrax spores (termed "woolsorters" disease) resulting in an
infection of the lungs (inhalational anthrax).
3.
From eating infected meat, resulting in gastrointestinal infection
(gastrointestinal anthrax). Gastrointestinal anthrax is generally not considered
a threat to U.S. forces.
What are the symptoms?
Symptoms of anthrax begin after a 1 to 6 day incubation period following
exposure.
For contact or cutaneous anthrax, itching will occur at the site of exposure
followed by the formation of a lesion. Untreated contact anthrax has a fatality
rate of 5-20 percent, but with effective antibiotic treatment, few deaths occur.
Initial symptoms for inhalational anthrax are generally non-specific: low grade
fever, a dry hacking cough, and weakness. The person may briefly improve
after 2 to 4 days; however within 24 hours after this brief improvement,
respiratory distress occurs with shock and death following shortly thereafter.
Almost all cases of inhalational anthrax, in which treatment was begun after
patients have
exhibited symptoms, have resulted in death, regardless of post-exposure
treatment.
What is the medical countermeasure?
Prior to exposure, prevention through vaccination, using the FDA-licensed
vaccine.
Otherwise, antibiotics such as penicillin, ciprofloxacin, and doxycycline are
the drugs of
choice for treatment of anthrax.
Treatment with antibiotics must begin prior to the onset of symptoms and must
include
vaccination prior to discontinuing their use.
The use of antibiotics keep the patient alive until their body can build an
immunity to
anthrax via vaccination. After symptoms appear however, inhalational anthrax is
almost
always fatal, regardless of treatment.
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