Anthrax

Question 1

What causes anthrax?

Answer 1

Bacillus antracis

• aerobic, Gram +, spore-forming rod

Question 2

What animals are most commonly affected by anthrax? How?

Answer 2

herbivores - cattle, sheep, goats

dehydrated spore with thick walls remains inactive in the environment for decades and germinates within the host and grow rapidly in the vegetative form –> fatal septicemia

• spores are resistant to heat, drying, and many disinfectants

Question 3

What is the most common sign of anthrax? What may precede this?

Answer 3

acute death

• staggering
• convulsions
• high fever
• extensive swelling
• cardiac or respiratory distress
• depression, stupor

Question 4

What are 4 key findings seen in cadavers that indicate anthrax?

Answer 4

1. bloody discharge from the nose, mouth, or anus
2. absence of rigor mortis
3. rapid bloating
4. dark blood that does not clot

Question 5

How is anthrax diagnosed? What is contraindicated?

Answer 5

submit blood or tissue sample in accordance with the procedures of the diagnostic lab

necropsy –> opening the carcass causes the more fragile vegetative bacteria to form resistant spores

Question 6

What are 3 ways of preventing anthrax?

Answer 6

1. rapid detection, reporting, and quarantine
2. vaccination –> given annually in endemic areas
3. post-exposure prophylaxis of asymptomatic animals for control in a herd

Question 7

How are carcasses with suspected anthrax properly disposed?

Answer 7

buried or burned without opening up the carcass and without moving the animal, which can spread the bacteria

Question 8

What are the 3 forms of anthrax seen in humans?

Answer 8

1. cutaneous (95%) - enters through a break in the skin, begins as papules and progresses to a vesicle then ulcerates –> black eschar
2. GI (rare) - from consumption of contaminated meat, begins as a sore throat and/or ulcerations with neck swelling and can progress to anorexia, vomiting, abdominal pain, and hemorrhagic diarrhea
3. inhalation - from breathing in the organism, severe respiratory disease with near 100% mortality, flu-like symptoms progress to massive bacteremia and shock

Question 9

What are 3 options for treating anthrax? How long?

Answer 9

1. Ciprofloxacin
2. Doxycycline
3. Penicilins

extended treatment up to 60 days to completely eradicate the organism