Bioterrorism/Poxviruses

Question 1

What are possible indications of a biological attack?

Answer 1

Noticing an unusual clinical case:

• not usual disease in this area
• more virulent
• in a different patient population

Unusual epidemiology:

• season
• mode of spread
• number and clustering of cases

Question 2

Who might be the most important front-line defender of a biological attack?

Answer 2

An ED physician b/c early diagnosis and treatment are critical.

Question 3

What findings were missing in the October 2001 that indicated a biological attack?

Answer 3

Anthrax CXR normally shows characteristic widening of the mediastinum. This was missing from 4 of 11 cases.

Question 4

Definition of Bio-warfare

Answer 4

The offensive use of biological agents by nations to harm the military of the enemy

Question 5

Definition of Bioterrorism

Answer 5

The intentional release or use of viruses, bacteria, fungi or other products for the purpose of harming or killing humans, animals, plants, and to influence the conduct of government or to intimidate or coerce the civilian population

Question 6

Definition of Bio-crimes

Answer 6

The use of biological agents or their products to attack or assassinate individuals (ie Ricin with Bulgarian dissident George Markov on Waterloo Bridge)

Question 7

Where does ricin come from?

Answer 7

It is the residue that remains after caster beans are boiled down into caster oil.

Question 8

What defense exists before an attack?

Answer 8

• Intelligence (NSA, CIA)
• Contingency planning
• Develop detection, drugs, vaccines to suspected agents

Question 9

What defenses for after an attack?

Answer 9

• Prevent additional attacks
• Detect and identify the microbial threat
• Coordinate public health to respond to the disease
• Develop vaccines and drugs to prevent or treat
• Scale up!
• Deliver to at-risk people (Stockpile drugs and vaccines for later threats)

Question 10

Does your response differ between an intentional release or an emerging infectious disease?

Answer 10

No, you respond the same way in either case.

Question 11

What is an organism that looks like anthrax, behaves like anthrax, but is not anthrax?

Answer 11

Bacillus cerus G9241

• somehow acquired the gene for a very similar toxin to anthrax pXO1 plasmid
• did NOT have a pXO2 plasmid which carries the genes for the synthesis of the D-glutamic acid capsule of anthrax… however, it still made a capsule.

Question 12

Types of biothreat agents

Answer 12

Toxins and Microorganisms

Question 13

Category A agents

Answer 13

Anthrax, Botulinum, Small pox, Tularemia

• easily transmissible
• high mortality and public health impact
• panic and social disruption
• require special action for preparedness

Question 14

Category B agents

Answer 14

Q-Fever, B. mallei, Ricin, Mycotoxins, Cholera

• moderately easy to disseminate
• moderate morbidity rates and low mortality
• require enhanced diagnostic capacity
• could be genetically enhanced for use as a weapon

Question 15

What is the purpose of putting cultures of anthrax and B. mallei in sugar cubes?

Answer 15

Infect shipments of horses, mules, cattle, sheep and reindeer

Question 16

How much anthrax is required to kill 3 million people?

Answer 16

100 kg

Question 17

How do you decontaminate a 520 acre island (contaminated with anthrax)?

Answer 17

280 tons of formaldehyde diluted in 2000 tons of seawater

Question 18

What happened in Sverdlovsk?

Answer 18

Accidental release of a live vaccine strain of anthrax. It does not have the plasmid that encodes the enzymes to make a capsule

Question 19

Ecthyma gangrenosum

Answer 19

Cutaneous anthrax - pathognomonic of pseudomonas aeruginosa sepsis

Question 20

Can someone be infected with smallpox, transmit it, and be asymptomatic?

Answer 20

Yes, for 3-4 days they will be infectious but asymptomatic

Question 21

Smallpox kills ___% of people it infects

Answer 21

30%

Question 22

When was the last known fatal case of smallpox?

Answer 22

UK in 1978

Question 23

What makes smallpox transmission spread so wide?

Answer 23

A sneeze releases thousands of virus enriched particles that can travel far. The people are often asymptomatic as well because there is a long incubation period.

Question 24

Orthopox viruses are large ___ viruses that replicate in the ___ of infected cells

Answer 24

DNA viruses that replicate in the cytoplasm

Question 25

Are there other hosts for smallpox?

Answer 25

No, humans are the only host.

Question 26

Smallpox pathogenesis

Answer 26

Inhalation & cutaneous contact
Incubation period: 7-17 days; primary viremia 3-4 days and then 8 + days get symptoms
Onset: Lymphocytes –> primarily in skin mucosa
Progression: varies from recovery scarring in 10-20 days to fulminant death in

Question 27

Evolution of smallpox rash

Answer 27

Macules -> vesicles -> pearly vesicles -> Pustules -> Scabs -> Scars (can be confluent malignant or hemorrhagic)

Question 28

What is used for smallpox vaccine?

Answer 28

Cowpox

there were 6 deaths a year in the US from the vaccine

Question 29

What has been stockpiled for smallpox?

Answer 29

The vaccine - there is enough to vaccinate the entire population of the US (even when diluted it is effective)