OCCUPATIONAL EXPOSURE TO BIOLOGICAL HAZARDS

AND

POST-EXPOSURE MANAGEMENT

INTRODUCTION

• Healthcare workers routinely exposed to biological hazards while caring for patients, handling laboratory specimens,

managing healthcare risk waste and cleaning contaminated environments.

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• Occupational exposure to infectious agents may result in:

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• Occupationally acquired infections.

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• Serious illness.

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• Long-term disability.

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• Psychological distress.

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• Absenteeism.

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• Increased healthcare costs.

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• Transmission of infection to patients, colleagues and family members.

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• Preventing occupational exposure is a shared responsibility involving healthcare workers,

management, Infection Prevention and Control Practitioners, Occupational Health Services and

Environmental Health Practitioners.

SCOPE

• What is biological hazard?

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• Common biological hazards in healthcare.

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• Routes of occupational exposure.

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• High-risk departments.

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• Factors increasing occupational exposures.

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• Preventing occupational exposures.

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• Standard precautions.

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• Sharps and needle-stick injuries.

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• Factors contributing to sharps injuries.

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• Preventing sharps injuries.

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• Immediate management following occupational exposure.

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• Medical evaluation.

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• Post-exposure prophylaxis

SCOPE (Cont….)

• Follow-up after exposure.

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• Whey healthcare workers do not report exposures.

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• Root cause investigation.

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• Occupational exposure to airborne, droplets and contact-transmitted diseases.

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• Modes of disease transmission.

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• Airborne diseases.

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• Occupational Tuberculosis.

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• Droplet-transmitted diseases.

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• Occupational immunization.

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• Screening programmes.

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• Biological spill management.

WHAT IS BIOLOGICAL HAZARD?

• A biological hazard (biohazard) is any biological agent that has the potential to cause disease in humans.

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• Example includes:

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• Bacteria.

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• Viruses.

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• Fungi.

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• Parasites.

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• Prions.

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• Biological toxins.

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• Healthcare workers may be exposed through direct patient contact, contaminated equipment,

environmental surfaces or occupational accidents.

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COMMON BIOLOGICAL HAZARDS IN HEALTHCARE

• Bloodborne pathogens

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• Hepatitis B virus (HBV)
• Hepatitis C virus (HBV)
• Human Immunodefiency Virus (HIV)

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• Commonly associated with sharps injuries and exposure to blood and certain body fluids.

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• Airborne pathogens

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• Mycobacterium tuberculosis
• Measles.
• Varicella-zoster virus

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• Organisms may remain suspended in the air and be inhaled by susceptible individuals.

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• Droplet-transmitted pathogens

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• Influenza virus
• SARS-CoV-2
• Neisseria meningitides

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• Transmission through respiratory droplets generated during coughing, sneezing or certain medical

procedures.

COMMON BIOLOGICAL HAZARDS IN HEALTHCARE (Cont….)

• Contact-transmitted pathogens

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• Staphylococcus aureus (including MRSA)
• Acinetobacter species.
• Norovirus

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• Are spread through direct contact or contaminated surfaces and equipment.

ROUTES OF OCCUPATIONAL EXPOSURE

• Percutaneous exposure

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• Needle-stick injuries.
• Scalpel injuries.
• Broken glass injuries.
• Other sharp medical devices.

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• One of the highest risk routes for bloodborne pathogen transmission.

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• Mucous membrane exposure

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• Occurs when infectious material contacts eyes, nose or mouth.

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• Blood splashes.
• Body fluid splashes.
• Laboratory accidents.

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• Non-intact skin exposure

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• Occurs when contaminated material contacts

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• Cuts.
• Abrasions.
• Dermatitis.
• Burns.

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ROUTES OF OCCUPATIONAL EXPOSURE (Cont….)

• Inhalation

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• Tuberculosis.
• Aerosol-generating procedures.
• Laboratory work.
• Environmental cleaning in contaminated areas.

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• Ingestion

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• Poor hand hygiene.
• Eating in clinical areas.
• Contaminated hands.

HIGH-RISK DEPARTMENTS

• Emergency Departments.

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• Operating Theatres.

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• Intensive Care Units.

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• Isolation Units.

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• Laboratories.

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• Dialysis Units.

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• Dental Clinics.

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• Mortuaries.

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• Laundry Services.

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• Healthcare Risk Waste Storage Areas

FACTORS INCREASING OCCUPATIONAL EXPOSURE

• Inadequate hand hygiene.

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• Failure to wear PPE.

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• Unsafe sharps handling.

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• Inadequate environmental cleaning.

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• Poor waste segregation.

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• Overcrowding.

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• Inadequate ventilation.

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• Fatigue.

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• Poor supervision.

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• Lack of training.

PREVENTING OCCUPATIONAL EXPOSURE

• Elimination

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• Eliminate unnecessary needle use.
• Remove unsafe equipment.

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• Substitution

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• Use needle-free systems where appropriate.
• Introduce safer sharps devices.

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• Engineering controls

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• Safety- engineered sharps.
• Sharps disposal containers.
• Biological safety cabinets.
• Negative-pressure isolation rooms.
• Local exhaust ventilation.

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• Administrative methods

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• SOP’s.
• Staff education.
• Vaccination programmes.
• Exposure reporting systems.
• Safe work practices.
• Routine audits.

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PREVENTING OCCUPATIONAL EXPOSURE (Cont….)

• Personal protective equipment

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• Gloves.

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• Masks.

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• Respirators.

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• Eye protection.

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• Face shields.

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• Gowns.

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STANDARD PRECAUTIONS

• Standard precautions apply to the care of all patients, regardless of diagnosis or presumed infection status.

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• Hand hygiene.

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• Appropriate PPE.

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• Respiratory hygiene and cough etiquette.

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• Safe injection practices.

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• Safe handling of sharps.

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• Environmental cleaning.

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• Safe handling of linen.

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• Healthcare risk waste management

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ENVIRONMENTAL HEALTH PERSPECTIVE

• EHP’s support biological hazard prevention by:

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• Conducting workplace risk assessments.

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• Inspecting environmental conditions.

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• Monitoring ventilation.

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• Evaluating healthcare risk waste management.

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• Auditing environmental cleaning.

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• Supporting Water Safety Programmes.

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• Advising management on biological risk reduction.

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• Participating in outbreak investigations.

PRACTICAL EXERCISE

• An EHP conducts a routine inspection of a district hospital’s Emergency Department.

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• The inspection identifies the following:

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• Sharps containers filled above the recommended level.
• Used PPE discarded in general waste bins.
• Inadequeate hand hygiene facilities at one treatment area.
• Overflowing clinical waste bins.
• Staff recapping needles.

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• A biological hazard risk assessment is undertaken.

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• Immediate corrective actions include:

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• Replacing sharps containers.
• Reinforcing safe sharps practices.
• Improving waste segregation.
• Restocking hand hygiene supplies.
• Providing refresher training on Standard Precautions.

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• Interventions reduce occupational exposure risks and strengthen Infection Prevention and Control.

SHARPS AND NEEDLE-STICK INJURIES

• Sharps injuries remain one of the most common occupational incidents in healthcare facilities.

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• Sharps injuries occurs when the skin is penetrated by a contaminated sharp object capable of transmitting infectious agents.

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• Hollow-bore needles.
• Suture needles.
• Scalpels.
• Lancets.
• Broken glass contaminated with blood or body fluids.
• Dental instruments.
• Orthopedic wires.

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• Injuries may expose healthcare workers to bloodborne pathogens (Hepatitis B virus, Hepatitis C virus or HIV)

FACTORS CONTRIBUTING TO SHARPS INJURIES

• Recapping needles.

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• Overfilled sharps containers.

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• Passing sharps by hand during procedures.

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• Inadequate lighting.

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• Fatigue.

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• Inexperience.

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• Rushing.

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• Inadequate training.

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• Unsafe disposal practices.

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• Poorly designed work areas.

PREVENTING SHARPS INJURIES

• Engineering controls

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• Safety-engineered needles,
• Needle-free intravenous systems.
• Puncture-resistant sharps containers.
• Sharps containers located close to the point of use.

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• Safe work practices

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• Never recap used needles except in the situation where an approved one-handed technique is used.
• Dispose of sharps immediately after use.
• Never overfill sharps containers.
• Avoid passing exposed sharps directly from person to person.
• Use forceps or instruments instead of fingers where appropriate.

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• Environmental controls

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• EHP’s should monitor for:

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• Availability of sharps containers.
• Appropriate placement of containers.
• Waste segregation practices.
• Safe transport of healthcare risk waste.
• Compliance during workplace inspections.

IMMEDIATE MANAGEMENT FOLLOWING OCCUPATIONAL EXPOSURE

• Step 1 – Stop the procedure safely Ensure the patient’s safety is maintained before attending to exposure.

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• Step 2 – Perform immediate first aid

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• For needle-stick injuries:

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• Wash the affected area immediately with soap and running water.
• Do not scrub aggressively.
• Do not squeeze or “milk” the wound.

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• For splashes to the eyes:

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• Rinse thoroughly with clean water/sterile saline.

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• For splashes to the nose or mouth:

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• Flush thoroughly with water.
• Do not swallow the rinse water.

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• NEVER USE HARSH CHEMICALS SUCH AS BLEACH OR DISINFECTANTS DIRECTLY TO

THE WOUND

IMMEDIATE MANAGEMENT FOLLOWING OCCUPATIONAL EXPOSURE (Cont…)

• Step 3 – Report the incident immediately

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• The immediate supervisor.
• Occupational Health Services.
• The designated Infection Prevention and Control or Occupational Health representative.

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• Step 4 – Document the incident

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• Reports should include:

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• Date and time of incident.
• Department.
• Type of exposure.
• Device involved.
• Activity being performed.
• Source patient information (confidentiality still to be maintained).
• Immediate actions taken.
• Witnesses (if applicable).

MEDICAL EVALUATION

• Following an occupational exposure, a qualified healthcare professional should conduct a medical evaluation:

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• Assessment should consider:

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• Type of exposure.

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• Severity of exposure.

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• Source patient information (where applicable).

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• Vaccination status of the exposed worker.

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• Previous occupational exposure.

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• Existing medical conditions that may influence management.

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• Medical evaluation should occur ASAP after exposure.

POST-EXPOSURE PROPHYLAXIS (PEP)

• PEP may reduce the risk of infection following certain occupational exposures.

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• PEP most effective when initiated promptly after exposure.

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• Depending on circumstances and current clinical guidelines, this may include:

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• HIV PEP.
• Hepatitis B vaccination and or Hepatitis B immunoglobulin where indicated.
• Follow-up testing and counselling.

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• Organisational protocols and national clinical guidelines for post-exposure management must be followed.

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• EHP’s should understand PEP process and ensure that system is in place for rapid referral and reporting.

FOLLOW-UP AFTER EXPOSURE

• Occupational Health Services should provide:

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• Follow-up clinical assessment.

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• Laboratory testing as indicated.

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• Counselling and psychological support.

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• Monitoring for signs and symptoms of infection.

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• Documentation of outcomes.

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• Clearance for return to work where appropriate.

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• Confidentiality should be maintained throughout the process.

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WHY HEALTHCARE WORKERS DO NOT REPORT EXPOSURES

• Fear of blame.

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• Lack of awareness.

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• Time pressures.

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• Belief that the injury is insignificant.

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• Fear of discrimination.

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• Lack of confidence in the reporting process.

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• Creating a positive safety culture encourages timely reporting

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ROOT CAUSE INVESTIGATION

• Every occupational exposure be investigated to identify underlying system failure.

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• Questions to be asked:

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• What happened?

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• Why did it happen?

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• Were Standard Precautions followed?

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• Was appropriate PPE available?

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• Was suitable equipment provided?

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• Were staffing levels adequate?

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• Could engineering controls have prevented the incident?

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• What corrective actions are required?

ENVIRONMENTAL HEALTH PERSPECTIVE

• EHP’s contribute by:

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• Monitoring sharps disposal practices.

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• Auditing healthcare risk waste management.

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• Identifying unsafe environmental conditions.

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• Participating in incident investigations.

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• Recommending engineering and environmental improvements.

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• Monitoring compliance with safe work practices.

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• Analysing exposure trends to identify recurring risks.

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• Role focuses on preventing future occupational exposures bmo improving the systems and

workplace environment.

PRACTICAL EXERCISE

• During a monthly OHS review, the EHP notes an increase in needle-stick injuries in the Emergency Department.

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Investigation findings

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• Several sharps containers were overfilled.
• Safety-engineered devices were not consistently available.
• Staff shortages resulted in increased workload.
• Some temporary staff had not received education and training.
• Near misses had not been reported.

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Improvement plan

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• The OHS Committee recommends:

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• Replacing sharps containers before they reach the recommended fill level.
• Increasing the availability of safety-engineered devices.
• Strengthening induction and refresher training.
• Reinforcing immediate reporting of exposures and near misses.
• Conducting monthly audits of sharps management.

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• Three months later, number of reported sharps injuries has decreased substantially.

OCCUPATIONAL EXPOSURE TO AIRBORNE, DROPLETS

AND CONTACT-TRANSMITTED DISEASES

• Healthcare workers at increased risk of exposure to infectious diseases because they provide direct patient care, handle

contaminated materials and work in environments where infectious agents may be present.

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• Understanding modes of transmission is essential for selecting appropriate preventive measures and protecting both

healthcare workers and patients.

MODES OF DISEASE TRANSMISSION

• Occupational exposure may occur through:

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• Airborne transmission.

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• Droplet transmission.

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• Contact transmission.

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• Blood and body fluid exposure.

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• Environmental contamination.

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• Different modes of transmission require different control measures.

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AIRBORNE DISEASES

• Airborne transmission occurs when infectious particles remain suspended in the air and are inhaled by susceptible individuals.

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• Examples include:

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• TB.

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• Measles.

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• Varicella (chickenpox)

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• Airborne pathogens remain suspended for prolonged periods and travel considerable distances within enclosed environments.

OCCUPATIONAL TUBERCULOSIS

• TB remains one of the most important occupational diseases affecting healthcare workers in SA.

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• Healthcare worker particular vulnerable because they:

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• Provide care for undiagnosed patients.

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• Perform aerosol-generating procedures.

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• Work in overcrowded healthcare facilities.

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• Spend prolonged periods in poorly ventilated environments.

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• EHP’s should regard tuberculosis prevention as a priority Occupational Health and Infection Prevention and Control activity.

PREVENTING OCCUPATIONAL TUBERCULOSIS

Reduce opportunities for transmission.

Reduce the concentration of infectious

particles.

DROPLET-TRANSMITTED DISEASES

• Droplet transmission occurs when infectious respiratory droplets are expelled during:

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• Coughing.
• Sneezing.
• Talking.
• Certain medical procedures.

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• Examples:

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• Influenza.
• Covid-19.
• Meningococcal disease.

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• Droplets generally travel short distances before settling onto surfaces.

PREVENTING DROPLET TRANSMISSION

• Control measures include:

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• Prompt identification of symptomatic patients.

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• Appropriate patients placement.

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• Respiratory hygiene.

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• Medical masks where indicated.

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• Eye protection based on risk assessment.

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• Hand hygiene.

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• Environmental cleaning.

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• Vaccination programmes where available.

CONTACT-TRANSMITTED DISEASES

• Contact transmission may occur through:

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Direct contact

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• Skin-to-skin contact.
• Direct patient care.

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Indirect contact

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• Contaminated equipment.
• Environmental surfaces.
• Linen.
• Medical devices.
• Shared patient-care equipment.

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Examples of organisms include:

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• Methicillin-resistant Staphylococcus aureus (MRSA).
• Norovirus.
• Multidrug-resistant Gram-negative organisms.

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OCCUPATIONAL IMMUNISATION

• Vaccination one of the most effective methods of preventing occupationally acquired infections.

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• Healthcare facilities should maintain comprehensive immunization programmes in accordance with national recommendations

and organizational policies.

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• Vaccination programmes may include:

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• Hepatitis B.
• Seasonal influenza.
• Covid-19.
• Measles.
• Varicella.
• Other vaccines based on occupational risk.

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SCREENING PROGRAMMES

• Occupational health screening may include:

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• Tuberculosis screening.

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• Health questionnaires.

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• Respiratory health assessments.

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• Immunisation status review.

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• Medical surveillance for high-risk staff.

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• Screening assist with early detection and protects both healthcare workers and patients.

ENVIRONMENTAL HEALTH PERSPECTIVE

• EHP’s support biological hazard prevention by:

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• Assessing ventilation systems.

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• Monitoring indoor environmental conditions.

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• Participating in TB Infection Prevention and Control programmes.

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• Evaluating environmental cleaning.

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• Monitoring waste management.

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• Supporting outbreak investigations.

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• Conducting workplace inspections.

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• Advising on environmental control measures.

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PRACTICAL EXERCISE

• An EHP investigates repeated reports of staff developing tuberculosis in a primary healthcare clinic.

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Investigation findings

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• Assessments identifies:

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• Poor natural ventilation.
• Overcrowded waiting areas.
• Delayed identification of patients with chronic cough.
• Limited staff awareness of respiratory hygiene.
• Inconsistent use of respiratory protective equipment during high-risk activities.

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Corrective actions

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• The multidisciplinary team implements:

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• Improved patient triage.
• Enhanced natural ventilation.
• Reorganisation of waiting areas to reduce crowding.
• Staff education on respiratory hygiene.
• Strengthened respiratory protection programme.
• Routine monitoring of ventilation and Infection Prevention and Control practices.

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• Follow-up evaluations demonstrate improved compliance and a reduction in occupational expose risk.

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BIOLOGICAL SPILL MANAGEMENT

• Biological spills involving blood, body fluids or other potentially infectious material be managed promptly and safely to minimize

occupational exposure and environmental contamination.

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• Examples include:

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• Blood spills.

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• Body fluid spills.

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• Laboratory specimen spills.

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• Culture spills.

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• Contaminated sharps incidents.

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• Every healthcare facility should have written biological spill management procedures.

BIOLOGICAL SPILL RESPONSE PROCEDURE

• The following general principles apply:

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Step 1 – Secure the area

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• Restrict access.
• Display warning signage if required.
• Prevent unnecessary movement through the contaminated area.

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Step 2 – Perform a risk assessment

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Consider:

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• Type of biological material.
• Quantity spilled.
• Location.
• Potential for aerosol generation.
• Number of people exposed.

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Step 3 – Wear appropriate personal protective equipment

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Depending on the risk assessment, PPE may include:

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• Gloves.
• Fluid-resistant gown or apron.
• Eye protection.
• Face shield.
• Respiratory protection where aerosol generation is a concern.

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BIOLOGICAL SPILL RESPONSE PROCEDURE (Cont….)

Step 4 – Clean and disinfect

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Follow organizational procedures for:

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• Safe removal of contaminated materials.
• Cleaning the affected area.
• Application of an appropriate disinfectant at the recommended concentration and contact time.
• Disposal of contaminated cleaning materials as healthcare risk waste.

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• Staff should always follow facility policies and manufacturer instructions for disinfectants.

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Step 5 – Waste disposal

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Dispose of:

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• Used PPE.
• Cleaning materials.
• Absorbent materials.
• Absorbent materials.
• Contaminated sharps.

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Step 6 – Report and document

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Document:

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• Date.
• Location.
• Material involved.
• Personnel involved.
• Corrective actions.
• Follow-up required

BIOLOGICAL HAZARD AUDITS