Anthrax is a disease caused by the bacterium Bacillus anthracis. It can infect both animals and humans. In animals, it mainly infects herbivores like cattle and sheep. In humans it is usually contracted occupationally through contact with infected animals. The bacterium exists in both a vegetative state that causes infection and a dormant spore form that allows it to survive in the environment for years. Testing for anthrax infection includes bacterial cultures, antibody tests, and PCR DNA analysis of samples. Treatment involves antibiotics like ciprofloxacin or doxycycline and vaccination can protect at-risk groups such as those working with animals or animal hides.
2. www.nps.gov/public_health/info/ppt/basicanthrax.ppt
Causative Agent - Anthrax
• B. anthracis (Gk: anthrakis –
“coal”)
– Large, spore-forming
bacterium
• Gram-stain positive
• Rod-shaped bacillus
• Non-motile
– Two states
• Vegetative - causes infection via
toxin production
• Spores
– Protective in adverse
environments
– May subsist for years
3. www.nps.gov/public_health/info/ppt/basicanthrax.ppt
Historical Aspects of Anthrax
• Disease of antiquity
– Biblical days
• Fifth Plague – Anthrax in cattle?
• Sixth Plague – Anthrax in humans?
– “Black Bane” (Europe – 1600) – Anthrax?
• Important disease in Public Health History
– Robert Koch – 1st
disease to satisfy postulates
– Firmly established microbial etiology (1876)
– First immunization for bacterial disease (1881)
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Historical Aspects of Anthrax (continued)
• Outbreaks
– Zimbabwe Outbreak (October 1979 – March 1980)
• 6,000 cases
– Paraquay – 1987
• 25 cases of cutaneous anthrax
• Associated with slaughter of a single, infected cow
– Russia (Sverdlovsk)
• 77 cases
• 66 deaths (primarily inhalational)
Note: few cases have occurred in the US in last century
9. www.nps.gov/public_health/info/ppt/basicanthrax.ppt
Public Health – Geographic Distn
• B. anthracis found
globally
– Central and South
America
– Southern and Eastern
Europe
– Asia
– Africa
– Middle East
• Countries with poor
veterinary medicine &
public health programs
• Occurs in animals in
United States
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Public Health – Popn
at Risk
• No person-to-person transmission
• Historically associated with occupational exposures
– Animal handling
– Rendering plants
– Preparing animal hides – Woolsorter’s Disease
• Accidental exposures have occurred
– Russian experience (Sverdlovsk)
– Biological weapons production
– Laboratory exposures
• Bioterrorism – recent events
15. www.nps.gov/public_health/info/ppt/basicanthrax.ppt
Medical Prevention and Treatment
• All forms of anthrax
– Floroquinolones-oral (Ciprofloxacin)*
– Doxycycline-oral**
• 100 mg BID for adults
• 1mg/pound BID for children (less than 100 pounds)
– Penicillin
– Others available
• Antibiotics effective for exposed persons
• Antibiotics effective early
* Drug of choice
** Approved by FDA for Anthrax on 18 October 2001
16. www.nps.gov/public_health/info/ppt/basicanthrax.ppt
Anthrax Vaccine Adsorbed (AVA)
• Licensed by FDA in 1970
• Vaccine consists of:
– Noninfectious sterile
filtrate from B. anthracis
culture
– Adsorbed to aluminum
hydroxide adjuvant
– Formaldehyde stabilizer
(<0.02% conc.)
– Benzethonium chloride
preservative
– Impossible to contract
disease from vaccine
• Dosage schedule:
– Six (6) doses
• 0, 2, 4 weeks
• 6, 12, 18 months
– Annual booster required
• Administered to:
– Healthy people
– 18-65 years of age
17. www.nps.gov/public_health/info/ppt/basicanthrax.ppt
Who Should Be Vaccinated?
• Work directly with B.
anthracis in the laboratory
• Persons who work with
imported animal hides or furs
in areas where standards are
insufcient to prevent
exposure to anthrax spores.
• Veterinarians
• Handle potentially infected
animal products in high-
incidence areas.
• Military personnel
Source: The Advisory Committee on Immunization Practices (ACIP)
