Chapter 9: Bioterrorism

INTRODUCTION AND EPIDEMIOLOGY

Bioterrorism is the release, or the threat of a release, of a biologic agent among a civilian population for the purpose of causing illness or death in humans, animals, or agriculture that results in the spread of fear and disruption of daily life. Such an occurrence is a low-probability but high-impact event. In the past century, the specter of bioterrorism was largely monitored by concerned government and military leaders, but in 2001, civilian emergency responders and healthcare institutions in the United States were thrust into the medical, psychological, and public health response to a real bioterrorist incident with very little training or preparation. In 2001, the U.S. Postal Service was used to deliver letters containing spores of Bacillus anthracis. The ensuing environmental contamination and health impact was widespread, resulting in 22 diagnosed cases of anthrax infections: 11 cases of inhalational and 11 cases of cutaneous anthrax.¹ Five patients died as a direct result of this intentional release of anthrax spores that was determined to have unnatural particle size characteristics.² Communities on the eastern seaboard of the United States were severely affected, with thousands of people receiving prophylaxis for anthrax.³ Fear then spread across the nation, as concern increased for a wider delivery of anthrax. In this century, there is growing angst in the scientific and medical communities regarding the potential for biologic agents to be modified using now common gene-editing tools such as CRISPR, resulting in the creation of organisms with an even greater potential to cause harm and spread fear.⁴

Preparedness efforts against emerging or resurging infectious diseases, including the pandemic H1N1 influenza response in 2009 and the international Ebola campaign in 2014, have enhanced our individual and systemic ability to effectively care for patients with austere infectious diseases. However, the intentional aspect of bioterrorism and the specter of directed harm to the public and to healthcare providers creates a different playing field that may hinder detection and response efforts, create a greater psychological burden to the public and responders, and possibly confound the treatment of patients due to organism enhancements or atypical presentation of naturally occurring infections.⁵

Biological agents with the potential to be used for bioterrorism are classified into two groups: biologically produced toxins and infectious organisms. Biologic toxins generally have properties similar to chemical agents. The health impact does not depend upon an incubation period to manifest disease in humans. Infectious organisms are further subdivided into two categories: contagious (propagating person to person) and noncontagious. Contagious agents have additional ramifications, both for protection of the healthcare workforce as well as propagation of the disease beyond the initially exposed population. The contagious agents of greatest concern, such as smallpox, plague (pneumonic), and certain viral hemorrhagic fevers, are infectious from person-to-person through airborne or droplet transmission. Until proven otherwise, however, the primary response to a suspected biological agent release should consider the agent to be ...