BIOLOGICAL TERRORISM
Edward L. Goodman, MD, Chief of Infectious Diseases Presbyterian Hospital of Dallas
December 14, 2005
Biological Terrorism
Use of biological agents to intentionally produce disease or intoxication in susceptible populations to meet terrorist aims Has been done in the past on a limited scale U.S. must be prepared to respond to this threat
History of Biological Warfare
In 1346, Tartar army hurled corpses of plague victims over the walls of Caffa, a seaport on the Crimean coast In 1718, Russians used same tactic against Sweden During the Pontiac Rebellion in 1763, the British army provided the Delaware Indians with blankets and handkerchiefs from the “Smallpox Hospital”
History of Biological Warfare
(cont.)
German program in WWI Japanese program in WWII In 1943, the U.S. began research into the offensive use of biological agents: Program stopped by President Nixon in 1969
History of Biological Warfare
(cont.)
In 1972, U.S. and many other countries signed the Biological Weapons Convention Former Soviet Union program began massive effort in 1970s Today, term “warfare” is outdated…terrorism of civilian populations major risk: Anthrax in 12 persons 2001
Why There was a Belief Bioterrorism in the U.S. Would Not Happen
Biologic weapons seldom used Their use is morally repugnant to most Technologically difficult? Concept of “nuclear winter” was “unthinkable” and thus dismissed until suicide hijackers and anthrax appeared
The “Coming of Age” and Bioterrorism
Perpetrators Availability of biological agents Methods of dissemination
The Spectrum of Terrorists
State-sponsored Insurgent/rebel Doomsday/cult-type group Non-aligned terrorists Splinter groups Lone offenders
Sources of Agents for Terrorism Use
World Directory of Collections of Cultures and Microorganisms
453 worldwide repositories in 67 nations 54 ship/sell anthrax 18 ship/sell plague
International black-market sales associated with governmental programs
Methods of Dissemination of Biologic Agents
Postal service: never previously reported Aerosol
Enclosed areas Community-wide
Mass produced food Water supplies
Ingestion
“You have to be lucky all the time. We have to be lucky just once!”
– Irish Republican Army
“The only difference between reality and fiction is that fiction has to make sense.”
– Tom Clancy
Syndromes Suggesting BT
Encephalitis Hemorrhagic mediastinitis Pneumonia with abnormal liver function Papulopustular rash Hemorrhagic fever Descending paralysis Nausea, vomiting +/- diarrhea
Biological Terrorism: Likely Agents
Bacterial:
Viral:
Toxin:
Anthrax Q fever Brucellosis Tularemia Plague Smallpox Viral encephalitides Viral hemorrhagic fever Botulism Ricin Staph, Enterotoxin B
Ideal Characteristics for Potential Biological Terrorism Agent
Inexpensive and easy to produce Can be aerosolized (1-10µm) Survives sunlight, drying, heat Cause lethal or disabling disease Person-to-person transmission No effective treatment or prophylaxis
Anthrax
Caused by Bacillus anthracis, a rod shaped, sporulating organism Is a zoonotic disease in cattle, sheep, and horses Transmission through scratches or abrasions of skin, wounds, eating insufficiently cooked infected meat, or inhalation of spores
Pathophysiology of Anthrax
Dixon, T. C. et al. N Engl J Med 1999;341:815-826
Cutaneous Anthrax Infection of the Hand and Cheek
Dixon, T. C. et al. N Engl J Med 1999;341:815-826
Anthrax (cont.)
Case fatality in untreated inhalational disease is almost 100%
In recent 2001 occurrence, “only” 3/6 died
Incubation 1 – 45 days, most within 21 days Initial flu-like symptoms are often followed by abrupt development of severe respiratory distress, shock, and death within 24 hours
Anteroposterior Chest Radiograph Obtained on Admission, Showing the Widened Mediastinum That Is Characteristic of Anthrax
Bush, L. M. et al. N Engl J Med 2001;345:1607-1610
Cerebrospinal Fluid Specimen Containing Many Polymorphonuclear White Cells and GramPositive Bacilli (Gram's Stain, x1000)
Bush, L. M. et al. N Engl J Med 2001;345:1607-1610
Differential Diagnosis of Clinical Manifestations of Anthrax
Dixon, T. C. et al. N Engl J Med 1999;341:815-826
Anthrax (cont.)
Medical management must be reserved for those with early symptoms or no symptoms Use of antibiotics for treatment (penicillin, ciprofloxacin, or IV doxycycline) and prophylaxis and vaccination No secondary transmission
Recommendations for Postexposure Prophylaxis
Swartz, M. N. N Engl J Med 2001;345:1621-1626
Recommendations for Antimicrobial Therapy of Clinical Inhalational Anthrax
Swartz, M. N. N Engl J Med 2001;345:1621-1626
Anthrax (cont.)
Weaponized by the U.S. in 1950s and 60s Major emphasis of USSR program Can be delivered as aerosol
Inhalational Anthrax Sverdlovsk, USSR, 1979
Incubation-Days Cases* Died Days to Death
0-6 7-13 14-20 21-27 28-44
6 28 9 6 11
6 25 7 6 5
4.5 2.5 3.0 4.5 3.5
* 15 additional cases without an exact date of onset; all died.
Shopping Mall Scenario - Denver
Anthrax aerosolized into shopping mall ventilation system; 10,000 people are present and 9,000 people are exposed; terrorist announces attack at 24 hours. 90% of exposed started on antibiotics by end of day 2, 10% cannot be found initially Total number hospitalized: 4,950; total requiring ICU care: 2,925; total deaths: 855; total ventilators required: 2601
Shopping Mall Scenario – Denver
(cont.)
The 13,000 military beds deployed for the Persian Gulf War would STILL not provide enough ICU beds (approximately 1,300) Even a small biological terrorism event completely overwhelms a city’s medical care resources
Smallpox
An even worse scenario
Smallpox
Killed more than 500 million persons in the 20th century despite being eradicated in 1978 Mortality of 30% in susceptible population Incubation period of 8 to 16 days
Smallpox (cont.)
Clinical manifestations begin acutely with fever, rigors, vomiting, headache and backache Approximately 10% of light-skinned patients exhibit erythematous rash during early phase Two to three days later, an enanthem appears on face, hands, and forearms
Smallpox (cont.)
Transmission begins with rash and lasts throughout convalescence Ongoing transmission is critical factor Most in the world are no longer protected by vaccination Currently vaccine and treatment limited
Date of Onset of Smallpox Cases by Two-Day Intervals Meschede Hospital, 1970
4
Cases
3
2 1
Hospital Stay Case 1
13
15
17
19
21
23
25
27
29
31
2
4
6
8
10
12
14
16
18
January
February
Plague
Not as likely but of concern
Botulism
Challenges in Recognizing a Bioterrorism Attack
Biologic agents with delayed onset Medical community is unfamiliar with many of these diseases Current surveillance system may not be adequate to detect attack
Epidemiological Clues to BT Event
Uncommon illness in epidemic form Explosive point source epidemic curve Unexplained high mortality Discordant attack rate: outdoor>indoor Sentinel illness – even one case of anthrax or smallpox
Syndromes Suggesting BT
Encephalitis Hemorrhagic mediastinitis Pneumonia with abnormal liver function Papulopustular rash Hemorrhagic fever Descending paralysis Nausea, vomiting +/- diarrhea
Ten Commandments Summary 1. Index of Suspicion 2.Protect Thyself and Thy Patients 3.Assess the Patient 4.Decontaminate 5.Diagnosis 6.Treatment 7.Infection Control 8.Alert 9.Epidemiologic Assessment 10. Spread the Gospel
Response Planning
Federal government State and local government Healthcare systems Media Infrastructure support
Impact on Healthcare System
Potential for widespread illness, in unprecedented numbers Limited therapeutic stockpiles Need special protective measures for medical care, clinical lab, and autopsy Panic/terror among the ill, the exposed, and healthcare providers
Other Critical Issues
Legal aspects
Criminal investigation Controlling civil disorder Quarantine
Continued public health activities
Planning Responses to Biological Terrorism
Are we ready? Should we get ready? Is it possible to be effectively prepared?
It’s not a matter of “if,” but when, which agent, and how bad it will be!
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