Bioterrorism

ACEM Fellowship

Table of Contents

Introduction

Release, or threat of release, of a biological agent with the intent to cause fear or harm
May be biologically produced toxins or infectious organisms
- Infectious agents may be contagious or non-contagious
- Contagious agents have greater ramifications for secondary exposure and propagation beyond target population
Class A agents
- The most severe potential and include Smallpox, B. anthracis and Yersinia pestis
Class B – Less potential for widespread illness
Class C – Possible future threats with improved technology
Typically, early symptoms can be attributable to many different agents e.g. athrax may present as influenza

Variola major
7-14 day incubation
Fever, myalgia, papular rash on face spreading to extremities (palms/soles) and then trunk
Vesicular then pustular
Can vaccinate within 4 days of exposure
Vaccinia immune globulin
- Best if given within 2-3 days of exposure. Consider use in those who cannot receive vaccination
Treatment is supportive

Bacillus anthracis
Cutaneous anthrax: Macule or papule then eschar with surrounding vesicles
GI anthrax: Abdo pain, vomiting, GI bleeding progressing to sepsis
Oropharyngeal anthrax: Sore throat, ulcers at base of tongue, unilateral neck swelling
Inhalational anthrax: Non-specific fever, dyspnoea, cough, headache, vomiting, chest pain, abdo pain then dyspnoea/diaphoresis/shock and haemorrhagic mediastinitis on CXR = widened mediastinum
Five-part vaccination possible
Prophylaxis: Cipro or doxy for 60 days
Three-drug IV regime for meningitis; Two-drug if no meningitis
Consider antitoxin (raxibacumab or anthrax Ig)

Yersinia pestis
Bubonic plague: Fever, chills, painful swollen lymph nodes, progressing to bubos (may be suppurative)
Pneumonic plague: Fever, chills, cough, gram-neg sepsis picture
Primary septicaemic plague: Gram-negative sepsis picture
Prophylaxis: Cipro or doxy for 10 days
Rx – Streptomycin or gentamicin

Clostridium botulinum
Foodborne: GI symptoms followed by symmetric cranial neuropathies, blurred vision and descending paralysis
Inhalational: Symmetrical cranial nerve palsies and descending paralysis
No prophylaxis
Antitoxin may preserve remaining neurological function but does not reverse paralysis

Filoviruses and arenaviruses (Ebola virus)
Non-specific febrile illness +- rash, progressing to bloody diarrhoea, bloody vomiting and shock

Activation of pre-planned all-hazards operation plan with bioterrorism-specific annex
Implementation of infection-control procedures
Information to all hospital departments and staff
Coordination of hospital media messages
Notification of public health agency

The most important assistance public health units can provide to all clinicians is the development of a community-wide patient evaluation and treatment protocol
This is crucial for subsequent predictable surge in non-specific presentations
Need clear and concise case definition imparting definitive clinical and diagnostic criteria for an individual patient
- Can separately define presumptive and confirmed case definitions

Medical surge response
Disease containment
- Need to identify precautions required for specific agent e.g. aerosol, droplet, body fluid
Decontamination if necessary
Screening on arrival
Supply management
- May need to provide smaller amounts of prophylactic antibiotics with view to later getting rest of course if in short supply
Printed instructions detailing level of risk and subsequent response with information on mode of transmission, measures that prevent spread and signs/symptoms with appropriate follow-up

Only indicated if recently exposed to suspected biological agent, not if symptoms have arisen
Derobing and washing with soap and water should be adequtae
Diluted bleach not indicated

Last Updated on November 23, 2021 by Andrew Crofton