PUHL101A MT Part 2

Page 1: Introduction to Biosafety

  • Definition of Biosafety:

    • A framework consisting of practices, training, safety equipment, and specially designed buildings.

    • Aims to protect workers, the community, and the environment from accidental exposure to infectious agents and toxins.

    • Encompasses rules and barriers to prevent biological risk.

  • Biological and Toxin Weapons:

    • Include microorganisms (virus, bacteria, fungi) and toxins produced by living organisms.

    • Intentionally released to cause disease and death in humans, animals, or plants.

  • Biosafety Programs:

    • Implement measures to identify biological hazards.

    • Evaluate health-related risks to humans, agriculture, wildlife, and the environment.

    • Identify ways to reduce health-related risks associated with biological hazards.

  • Laboratory Settings Using Biosafety Principles:

    • Human and veterinary clinical and diagnostic laboratories

    • Biological research and production laboratories (academia, industry, government)

    • Environmental research and analytical laboratories

    • Academic and teaching laboratories

  • Laboratory Biosafety:

    • Describes the use of biosafety principles and practices to minimize risks from handling infectious agents, toxins, etc.

    • Crucial for laboratories that handle infectious microorganisms affecting humans, animals, and plants.

  • World Health Organization (WHO) Definition of Biosafety:

    • A strategic and integrated approach to analyzing and managing risks to life and health in humans, animals, and the environment.

    • Recognizes interconnections between sectors affecting biological contamination.

  • Key Concepts in Biosafety:

    1. Biological Hazard: Potential risk from uncontrolled exposure to biological agents.

    2. Biocontainment: Measures to prevent the leakage of infectious diseases from research centers.

    3. Bioprotection: Measures to reduce risks of loss, theft or misuse of pathogens and toxins.

  • Elements of Biosafety:

    • Biosafety is complex and requires strict rules/barriers to prevent exposure to infectious agents.

Page 2: Laboratory Practices and Techniques

  • Containment Objectives:

    • Containment of harmful biological agents to reduce exposure to personnel and environment.

    • Vaccine use for personal protection.

  • Risk Assessment:

    • Determines the combination of factors needed for safe handling of specific agents.

  • Laboratory Practices and Technique:

    • Strict adherence to microbiological practices is vital.

    • Development of a biosafety manual to identify hazards and outline safety procedures.

  • Safety Equipment (Primary Barriers and PPE):

    • Safety Equipment Includes:

      • Biological Safety Cabinets (BSCs)

      • Enclosed containers and engineering controls.

      • Various personal protective equipment (e.g., gloves, gowns, respirators).

  • Types of Biological Safety Cabinets:

    1. Class I: Open-fronted BSCs for personnel protection.

    2. Class II: Provides protection from contamination of materials.

    3. Class III: Fully enclosed for maximum protection.

  • Facility Design and Construction (Secondary Barriers):

    • Essential for protecting workers, and surrounding community from biological hazards.

    • Appropriate facility designs vary according to recommended biosafety levels (BSLs).

  • Safety Requirements for Different BSLs:

    • BSL-1: Basic containment for well-characterized microorganisms not causing disease.

    • BSL-2: For moderate-risk agents, includes practices to minimize exposure.

    • BSL-3: For agents causing serious or potentially lethal infections, strict procedures are required.

    • BSL-4: Highest level for agents posing a significant risk of aerosol transmission.

Page 3: Detailed Biosafety Levels

  • Biosafety Level 1 (BSL-1):

    • Suitable for undergraduate and teaching labs.

    • Involves non-disease-causing microorganisms (e.g., Bacillus subtilis).

    • Basic level with standard microbiological practices required.

  • Biosafety Level 2 (BSL-2):

    • Clinical, diagnostic, and teaching labs; moderate-risk agents.

    • Requires personal protective equipment and safety measures against exposure through sharp instruments.

    • Examples include Hepatitis B, HIV, and Salmonella.

  • Biosafety Level 3 (BSL-3):

    • Work involving serious and potentially lethal respiratory pathogens (e.g., Mycobacterium tuberculosis).

    • Strict controls for aerosol and contact exposure. Controlled access is mandatory.

  • Biosafety Level 4 (BSL-4):

    • For work with dangerous agents with no known vaccine or treatment (e.g., Ebola virus).

    • Complete isolation from infectious materials, often requiring specialized facilities and personnel suits.

Page 4: Animal Biosafety

  • Animal Biosafety Overview:

    • Focus on hazards involved with administering infectious agents to research animals (e.g., bites, shedding).

    • Different animal biosafety levels are necessary for housing and using infected animals.

  • Animal Biosafety Levels (ABSL):

    • ABSL-1: Minimal hazard, agents that don't cause disease in health adults.

    • ABSL-2: Moderate hazards from agents associated with human disease.

    • ABSL-3: Potential for aerosol transmission, serious disease risk.

    • ABSL-4: High-risk agents, potential for aerosol transmission or unknown risks.

  • Roles of Laboratory Animals:

    • Enhance diagnostics, understanding microbial resistance, vaccine development, and advanced medical technologies.

  • Ethical Considerations:

    • Decisions to use animals should aim for significant contributions to welfare or knowledge.

    • Adoption of the 3Rs (Replacement, Refinement, Reduction) is essential for ethical animal research.

Page 5: Laboratory Animal Care and Management

  • The 3Rs of Animal Research:

    1. Replacement: Avoid using animals where possible.

    2. Refinement: Modify practices to enhance animal well-being and minimize pain.

    3. Reduction: Use fewer animals for similar scientific outputs.

  • Institutional Animal Care and Use Committee (IACUC):

    • Ensures compliance with regulations involving research with animals.

    • Conducts reviews of research proposals and monitors animal welfare standards.

  • Veterinarians' Role:

    • Promote animal welfare and ensure humane care through research activities.

Page 6: Environmental and Housing Requirements

  • Environmental Considerations for Laboratory Animals:

    • Climate Control: Temperatures should ideally match human tolerance, typically around 20-25°C.

    • Humidity: Maintain at around 50% to promote health, while tolerating up to 70% if conditions are stable.

  • Facility Management:

    • Must minimize noise levels to avoid stress on animals.

    • Odor control is necessary for a healthy environment.

  • Laboratory Animal Care Practices:

    • Ensure cleanliness and sanitation of cages and facilities to prevent disease.

    • Proper waste disposal and vermin control are critical for maintaining hygiene and health.

  • Emergency Care:

    • Continuous responsibility of staff; they must be prepared for emergency handling of animals.