Microbial Forensics and Bioterrorism

Overview

• Microbial Forensics: The science that combines epidemiology with genomics and microbiology to investigate incidents involving biological agents.
• Sample Collection: Strategies and challenges in collecting microbial samples.
• Biological Weapons: Discussion on the nature, spread, and threat posed by biological weapons.
• Biocrime and Bioterrorism: Definitions and distinctions between biocrimes and bioterrorism.
• Case Studies on Anthrax: Examination of notable anthrax incidents.

What Is Microbial Forensics?

• Extends epidemiological principles to explore unlawful acts involving biological agents.
• Combines multiple scientific disciplines to attribute causes of incidents involving harmful pathogens.
• Defined as analyzing evidence from bioterrorism or biocrime for attribution purposes (Rasko et al., 2011).

Key Concepts in Microbial Forensics

• Attribution: Assigning origin of microbial samples to a known source with high certainty while excluding others.
• Comparison to conventional forensics: traditional evidence includes fingerprints and fibers; microbial forensics includes microbial evidence.

Key Investigative Questions

• Did a crime occur?
• What happened, and how did it occur?
• When, where, and why did it occur?
• Who was involved, and what evidence exists?
• How reliable is the evidence, and what alternative explanations are possible?

Microbial Evidence Collection

• Establish a chain of custody for evidence.
• Differences in handling microbial evidence compared to traditional evidence (e.g., fingerprints).
• Important to protect evidence during collection, transport, and storage to prevent contamination and ensure reliability.

Biological Weapons Overview

• Considered weapons of mass destruction with the ability to cause large-scale harm.
• Capable of injuring or killing thousands, spreading fear and panic, and serving as force multipliers in conflicts.

Availability of Biological Weapons

• Potential acquisition by rogue states and the black market (notably ex-Soviet states).
• Numerous research institutes and clandestine labs advance accessibility.

Characteristics of Weapons of Mass Destruction (WMD)

• Advantages:
  • Inexpensive to produce
  • Easy to manufacture and deliver
  • Highly lethal in small quantities
  • Difficult to detect due to possible long incubation periods
  • Few forensic signatures; can obscure attack traces

Agriculture and Bioweapons

• Unique vulnerabilities include low technical barriers for weaponization and minimal security around targets.
• Lower moral barriers may facilitate the use of biological agents in agricultural contexts.

Biocrime vs Bioterrorism

• Biocrime: Acts targeting individuals using biological agents; motivated often by revenge or financial gain.
• Bioterrorism: Using biological weapons with goals similar to conventional terrorism (e.g., mass harm, societal disruption).

Biological Agents

• Pathogens: Microorganisms causing disease (viruses, bacteria, fungi, etc.).
• Toxins: Poisonous chemicals produced by living organisms; differ from pathogens as they are non-replicating.
• Categorized by the CDC into three classes based on risk and spread potential:
  • Category A: High risk (e.g., Anthrax, Smallpox).
  • Category B: Moderate risk (e.g., Brucellosis, Typhus).
  • Category C: Emerging pathogens (e.g., Nipah virus)

Modes of Dissemination of Biological Agents

• Aerosol Transmission: Effective for respiratory agents.
• Water Contamination: Municipal supplies may dilute pathogens but can still be targeted.
• Food Contamination: High risk for attacks targeting uncooked or heat-stable food.

Consequences of Biological Agent Attacks

• Delayed onset of symptoms complicates early detection.
• Distinguishing between a biological attack and a natural outbreak can be challenging.

Anthrax Case Studies

The Kameido Incident

• Associated with Aum Shinrikyo's attempts to use Bacillus anthracis spores.
• Investigations into symptoms reported by locals raised concerns about possible aerosolized anthrax.

The Amerithrax Task Force

• After 9/11, there was heightened concern for biological attacks: anthrax letters sent to various media outlets and politicians.
• Analysis of extracted anthrax identified it as Ames strain, linked to lab research, suggesting deliberate action.
• Detailed forensic approaches, including carbon dating and genetic analysis, narrowed down suspects, ultimately implicating Dr. Bruce Ivins posthumously.

Review

• Microbial forensics involves detailed investigative techniques for biocrimes and bioterrorism, especially concerning evidence handling and analysis to attribute biological attacks effectively.