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Microbe of the Week
Bacillus Anthracis
•Rod shape bacterim
•Gram positive
• Causative agent for anthrax
• Exists in two forms
Vegetative and Endospore
Bacillus anthracis
Spore form
• Soil dwelling
• Exceptionally viable. Can exists for
decades
• Dormant until an optimal
environment presents itself.
• Sporicides have the ability to kill
the spores.
Bacillus anthracis
Vegetative State
•Bacteremia- Blood pathogen
•Vaccine is available
•“Anthrax spore vaccine”
•Very easily killed
•Increased risks amongst
professionals that work with
livestock.
Background
• Bacillus anthracis was the first disease-causing
bacterium discovered
• Discovered in 1877 by Robert Koch
– Koch also discovered tuberculosis bacillus and
cholera vibrio
• Anthracis means “coal”, which refers to the black lesions
formed by the cutaneous form of the disease
Disease
Cutaneous Anthrax
• Organism enters through
a break in the skin
• Most common
• Causes swelling and
lesions
• Only a small percentage
of cutaneous infections
are fatal
Inhalation Anthrax
• Organism enters through the
respiratory tract
• Mortality rate is near 100%
• Initial flu-like symptoms that
progress to hypotension,
bacteremia and toxemia
Intestinal Anthrax
• Contracted from consumption of contaminated meat
• Symptoms include anorexia, nausea, vomiting and
abdominal pain along with hemorrhagic disrrhea
• Can become systemic and fatal
