Anthrax is a bacterial infection caused by the spore-forming
bacterium Bacillus anthracis.
Where is anthrax
Anthrax exists naturally in wild and domestic animals, such
as cattle, sheep, goats, and other herbivores, it can also occur in humans who
are exposed to infected animals or tissue from infected animals.
can be found globally, but it is more common in developing countries or countries
without veterinary public health programs. Antrax is found parts of South and
Central America, Southern and Eastern Europe, Asia, Africa, the Caribbean, and
the Middle East.
How common is anthrax?
incidence is unknown, but outside of 'at risk' areas, anthrax is extremely rare.
In the United States, only 236 anthrax cases were reported between 1955 and 1999,
an average of about five per year. Most of those were in people who work with
Anthrax has, however been seen as a convenient and inexpensive
biological weapon, and this unquantifiable risk should be taken seriously.
is anthrax transmitted?
Anthrax affects humans via occupational exposure
to infected animals or their products. Workers in other counties, who are exposed
to imported dead animals and animal products, may become infected with B. anthracis
Anthrax can be transmitted in three different ways:
- Cutaneous (skin), B. anthracis spores can live in the soil for many
years, and humans can become infected by contact with the soil, or handling products
from infected animals
- Inhalationor of anthrax spores from contaminated
animal products. i, and .
- Gastrointestinal: Anthrax can be spread by eating
undercooked meat from infected animals.
anthrax be spread from person-to-person?
There is no evidence of unintended
infection, even from people with inhalation anthrax; ther is a risk of infection
from spores released into the atmosphere or air supply accidentally (eg from a
laboratory) or intentionally (eg terrorism)
Who is most
- People working with imported meat or hides from
- People travelling 'rough' in endemic areas
What are the symptoms of anthrax?
Infection usually occurs when spores enter via a cut or abrasion on the skin,
such as when handling wool, hides, leather or hair from infected animals. Skin
infection begins as a raised itchy bump that may be mistaken for an insect bite;
within 48 hours, it develops into a vesicle and then a painless ulcer, usually
1-3 cm in diameter, with a characteristic black necrotic (dead) area in the center.
Lymph glands in the adjacent area may swell. About one in five untreated cases
of cutaneous anthrax will result in death.
symptoms will progress over several days to severe breathing problems; inhalation
anthrax is usually fatal.
Gastrointestinal: Acute inflammation of
the gut shows as nausea, loss of appetite, vomiting, and fever. These usually
lead to abdominal pain, severe diarrhea, and vomiting of blood. Intestinal anthrax
has a death rate approaching 50%.
How is anthrax
Diagnosis is confirmed by isolating B. anthracis from
the blood, skin lesions, or respiratory secretions or by measuring specific antibodies
in the blood.
Tests are available to confirm the diagnosis within an hour;
testing is taking place in Switzerland for a test that will confirm the presence
of anthrax in a few minutes.
Is there a treatment
Antimicrobial treatment is usually effective
if commenced in good time. If left untreated,
the disease can be fatal. Treatment success
(and the time available) depends on the
form of the disease (cutaneous, inhalation
or intestinal). Ciprofloxacin is still the
antibiotic of choice ('first line therapy')
- but antimicrobial therapies are subject
to culture and sensitivity results from
the laboratory; doxycycline and procaine
penicillin may be used. In pregnant women,
drugs and dosages may need to be reviewed
to ensure the foetus gains maximum benefit
In 2012, the U.S. Food and
Drug Administration approved raxibacumab
injection to treat inhalational anthrax.
Raxibacumab is a monoclonal antibody that
neutralizes toxins produced by B. anthracis
that can cause massive and irreversible tissue
injury and death (FDA 2012).
there a way to prevent infection?
There is an animal vaccine, which is
not unioversally used; there is also an anthrax vaccine for use in humans, which
offers over 90% protection against anthrax.
In areas where anthrax is common
and animal vaccination levels are low, contact with livestock and animal products
must be avoided, meat that has not been properly slaughtered and thoroughly cooked
should also be avoided.
What is the mortality rate
Untreated cutaneous anthrax has
a mortality rate which varies
from five to twenty per cent. Deaths
are rare with early diagnosis and
appropriate antibiotic therapy.
What is the anthrax vaccine?
vaccine is a cell-free filtrate vaccine, which means it contains no dead or live
bacteria in the preparation. Mild local reactions, such as tenderness and redness
at the injection site, occur in almost a third of recipients. Severe local reactions,
involving extensive swelling of the forearm as well as the local reaction, are
infrequent. Systemic reactions are rare.
the protocol for anthrax vaccination?
The immunization consists of three
subcutaneous injections given two weeks apart followed by three additional subcutaneous
injections given at 6, 12, and 18 months. Annual booster injections of the vaccine
are recommended thereafter. Pregnant women are only vaccinated if absolutely necessary.
should get vaccinated against anthrax?
- People who work with the organism
- People who work with imported animal hides or furs where
there is a risk of exposure to anthrax spores.
- People who handle potentially
infected animal products in high-incidence areas.
- Military personnel posted
in high risk locations.
Are there adverse reactions
to the anthrax vaccine?
The most common reactions are temporary redness,
swelling or a small lump at the injection site; even these occurrancies have been
uncoomon, with about 100 reports after some 400,000 people had received the vaccine.
Can anthrax be controlled environmentally?
can survive in the ground as a spore for many years before being activated and
infecting animals or people; in its natural cylcle, the death of the infected
creature then allows reinfection of the ground. Until the next time.
there legal protection for workers and others?
Workers are entitled to
appropriate training and protective equipment
U.S. Food and Drug Administration, FDA
approves raxibacumab to treat inhalational anthrax [Press
Meaney-Delman D, et al; Prophylaxis and treatment of anthrax
in pregnant women, DJ.Obstet Gynecol. 2013 Oct;122(4):885-900 abstract
and Further Information Sources
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Article written by Andrew Heenan BA (Hons), RGN, RMN