56 Bioterrorism and its impact on the PACU

Aerosolization: A gaseous suspension of organisms that contains minute particles.

CBRNE: Chemical, Biologic, Radiologic, Nuclear, Explosive event.

Cohort: Group together with similar likenesses.

Dirty Bomb: A mix of explosives, such as dynamite, with radioactive powder or pellets. The dynamite explodes and carries material into the surrounding area (e.g., radioactive material, biologic agents).

Empiric Treatment: Broad-based antibiotic treatment based on prior experience with the microorganism.

Sepsis: The body’s response to an infection.

Septic Shock: Multiple organ failure resulting from advancement of severe sepsis.

Weapon of Mass Destruction (WMD): A former Soviet Union term that was used to denote nuclear, chemical, and biologic weapons. The term has been broadened to include radiologic weapons. Since the World Trade Center airliner attacks, the term includes any means to cause mass casualties.

Before September 11, 2001, terrorism did not have the full attention of the average American as it does today.¹ However, with our past experience and current knowledge, we must be able to define what bioterrorism is and how it impacts the postanesthesia care unit (PACU).

The Centers for Disease Control and Prevention (CDC) define bioterrorism as the intentional release (or threatened release) of viruses, bacteria, or their toxins for the purposes of harming or killing citizens.² Potential vehicles of releasing the biologic agents include aerosolization, insects, and food and water source contamination.² As a critical care unit, the PACU will be challenged to adapt usual care to supplement mass casualty victims of bioterrorism. The PACU must prepare immediately for this inevitable role, brainstorming scenarios by participating in mock disaster drills and augmenting staff competencies. The release of biologic weapons is specifically designed to promote or spread fear or intimidation upon an individual, a specific group, or the population as a whole for religious, political, ideological, financial, or personal purposes.³ Overwhelming terror and panic are just two of the psychological goals, with incapacitation and destruction as the ultimate objectives. Deliberate release of biologic agents is a growing and real threat, because the agents are easier to acquire and are more likely to be used. Unlike nuclear, radiologic, or chemical attacks, biologic attacks can be overt or covert and much easier to deploy. Covert attacks offer no immediate effects on victims because of a delay between exposure and onset of illness (incubation period).⁴ There are several advantages of covert biologic operations including: biologic agents are easier to hide, decreasing the chance of disclosure; biologic agents are cheaper, allowing small radical groups or single individuals access; and release might not be detected until the incubation period is completed, eliminating the “window of opportunity” for postexposure prophylaxis.⁵

* The views expressed in this manuscript are those of the author and do not reflect the official policy or position of the Department of the Army, Department of Defense, or the U.S. Government.

There is a plethora of biologic agents that could be used in bioterrorism. Rapid and accurate diagnosis may be hindered because of the commonality of symptoms (e.g., fever, body aches, lethargy) with other universal illnesses. With a delay in diagnosis, there is a greater the chance of infecting a much larger population. The goal of the perpetrator may include a multitiered reaction, including the initial release of a toxic substance and followed by fear and panic in the populace that could lead to a physical injury in conjunction to exposure to toxic biologic agents. It is critical to remember that when a civilian population is the target of a biologic attack, the diversity in age and health status influences overall outcomes. Victims of bioterrorism rely on health care providers to be cognizant of the rapid detection and proper treatment of exposure to a multitude of items.

Historical use of bioterrorism

Greek history documents one of the earliest written descriptions of biologic weapons being used. In 184 BC, Hannibal used snakes as a biologic weapon by casting pots of poisonous snakes into the midst of the Pergamene forces, ultimately defeating them. In 300 bc, the Greeks used decaying bodies to pollute the water supply of their enemies.¹ In the fourteenth century, bodies infected with plague were catapulted over the walls of cities in an attempt to infect the habitants and attenuate their defenses. Blankets that were once used to wrap smallpox victims were subsequently distributed to Native Americans in an effort to infect and incapacitate them. The use of biologic weapons continued into the 1900s, and stakes became higher as the sophistication of microbiology improved and travel became easier. During World War I, the Germans inoculated horses and cattle with anthrax and glanders before shipping them to France.⁶ In 1937, Japan started a biologic warfare program code named Unit 731. An investigation after World War II revealed that the Japanese used prisoners of war as research subjects for aerosolized anthrax and also dropped plague-infected fleas over China and Manchuria.⁶

In 1925, the Geneva Protocol called for the first multilateral agreement for the prohibition of biologic warfare.¹ This agreement served to describe biologic warfare, but did not address the prevention of their use. During World War II, there were accusations that the United States used biologic agents against the Eskimos in Canada and released the Colorado beetles on crops in Germany. In 1942 at a small National Guard airfield (Fort Detrick), the United States began a research and development program on the use of biologic agents. This program produced agents and conducted field testing on biologic agents until 1969, when President Richard Nixon stopped all offensive biologic and toxin weapon research and production by executive order. In 1953, the United States initiated a medical defensive program against biologic warfare at the U.S. Army Medical Research Institute of Infectious Disease that continues today.⁷ Over recent decades, the threat has changed from Cold War scenarios to the asymmetric and terrorist threat.⁵ In 1978 the toxin “yellow rain,” was used in the assassination of a exiled Bulgarian in London.⁶ Terrorist plots to use ricin were uncovered in England in January 2003, in a South Carolina postal office, and in the Dirksen Senate Office Building in Washington D.C.⁶ Lawmakers were directly affected in October 2001 when an anthrax contamination resulted in the closing the Hart Senate Office Building in Washington D.C. shortly after the terrorist attack on September 11, 2001.⁶ Radical groups or individuals can easily gain access to biologic agents. Iraq had a large biologic weapons program, and in 1995 they admitted to producing and deploying bombs, rockets and aircraft spray tanks containing Bacillus anthracis and botulinum toxin.⁷ In 1995, a cult in Japan released sarin gas in a Tokyo subway, resulting in significant injury. This same group had additional plans for biologic terrorism involving botulinum toxin, anthrax, and drone aircraft carrying spray tanks.⁷ They had also traveled to Zaire in 1992 to obtain Ebola virus.⁷ It is concerning that access to once highly protected biologic weapons is becoming easier for the highest bidder. In the former Soviet Union, one of the former biologic weapons laboratory facilities, highly protected in the 1980s, was left vulnerable with a few guards who had not been paid in months. The location of the smallpox, Ebola, Marburg, and hemorrhagic fever viruses that were stored there remain unknown.⁷ Today’s global economy, free and mobile society, instant Internet connectivity, and continued research indicate the most worrisome infections have yet to be recognized.⁶

Bioterrorism agents

The Centers for Disease Control and Prevention (CDC) classifies bioterrorism agents into three groups (Table 56-1). Category A includes high-priority agents that could pose a risk to national security because they can be easily disseminated, result in high mortality rates, have the potential for major public health impact, might cause public panic, and require special action for public health preparedness.⁸ Category B includes agents that are moderately able to be disseminated, resulting in moderate morbidity and low mortality rates, and require specific enhancements of the CDC’s diagnostic capacity and enhanced disease surveillance.⁸ Category C is the lowest priority and includes emerging pathogens that could be engineered for mass dissemination in the future because of the availability, ease of production, dissemination, and the high morbidity and mortality rates and major health impact.⁸

Table 56-1 CDC Categories of Bioterrorism Agents and Diseases

CATEGORIES	BIOTERRORISM AGENTS AND DISEASES
Category A	Anthrax (Bacillus anthracis) Botulism (Clostridium botulinum toxin) Plague (Yersinia pestis) Smallpox (variola major) Tularemia (Francisella tularensis) Viral hemorrhagic fevers (e.g., Ebola, Marburg, Lassa)
Category B	Brucellosis (Brucella species) Food safety threats (Salmonella species, Escherichia coli, Shigella) Glanders (Burkholderia mallei) Q fever (Caxiella burnetii) Ricin toxin Viral encephalitis (VEE, EEE, WEE)
Category C	Emerging infectious diseases Nipah Hantavirus SARS

CDC, Centers for Disease Control and Prevention; EEE, eastern equine encephalitis, SARS, severe acute respiratory syndrome; VEE, Venezuelan equine encephalitis; WEE, western equine encephalitis.

From Woods JB: USAMRIID’s medical management of biological casualties handbook, ed 6, Fort Detrick, Frederick, Md, 2005, U.S. Army Medical Research Institute of Infectious Disease, available at www.usamriid.army.mil/education/bluebookpdf/USAMRIID%20BlueBook%206th%20Edition%20-%20Sep%202006.pdf. Accessed April 10, 2011.