Risk Assessment for the TB Laboratory

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2 Risk Assessment for the TB Laboratory Wisconsin Mycobacteriology Laboratory Network (WMLN) Annual Confererence November 4, 2015 Erin Bowles

3 A National Biosafety and Biosecurity System in the United States A WHITEHOUSE blog Summary of a memorandum issued 10/19/15 By continuing to review inventories, lab safety procedures, and security best practices, facilities can help achieve a laboratory culture of responsible conduct. Therefore we continue to strongly encourage the application, at non-federal as well as Federal facilities, of core principles, best practices, and the recommendations released today. 2

4 Be Aware! Attainment of competency Increased workload Repetitive nature of work Leads to complacency Increased risk of exposure 3

5 Risk Assessment Experience Which of the following statements best describes your experience with risk assessment? A.) I don t have a clue what risk assessment is and have never done one. B.) I have heard of risk assessment and know what it is, but have never participated in a laboratory risk assessment. C.) I have heard of risk assessment and have participated as part of a group in performing a risk assessment. D.) I understand risk assessment very well, have performed several risk assessments and incorporate it into my daily work. 4

6 Lab Safety Begins With Risk Assessment Assess biological risks Identify hazards Consider the agent, the host, and the environment Estimate risk based on likelihood and severity of the occurrence Risk mitigation and exposure avoidance Identify and implement controls and work practices Monitor effectiveness Review all accidents, exposures and near misses Review effectiveness of control measures Identify training needs Modify procedures 5

7 Beginning Your TB Risk Assessment Infectious Agent Perform a risk assessment to identify the infectious agents you are likely to be working with and the likely route of exposure. Infectious agents: Mycobacteria tuberculosis complex Non-tuberculous mycobacteria Infectious dose As few as 1-10 organisms causes disease Route of infectious: Aerosols inhalation Needle stick percutaneous inoculation 6

8 Beginning Your TB Risk Assessment Facility Perform a risk assessment to determine the biosafety level your TB laboratory has been designed to meet. My TB laboratory is designed as a? A.) BSL-2 laboratory B.) BSL-3 laboratory 7

9 Beginning Your TB Risk Assessment Facility Mycobacteriology is performed in? A.) A separate BSL-3 facility B.) A separate room that is BSL-2, but is negative pressure from the rest of microbiology. C.) Within the BSC that is in the main microbiology area. We don t have a separate room. 8

10 TB Laboratory Biosafety Level MMWR: Guidelines for Safe Work Practices in Human and Animal Medical Diagnostic Laboratories If your laboratory manipulates AFB cultures for identification and characterization: Separate TB laboratory Ideally would meet BSL-3 requirements BSL-2 plus negative airflow and use of respiratory precautions may be used, provided a risk assessment has been conducted. 9

11 Recommendations Before opening any TB specimen container, disinfect the outside of the container with gauze soaked in a tuberculocidal disinfectant. TB decontamination, propagation and culture manipulation are performed in a BSL-3 lab. If a laboratory is unable to retrofit a BSL-2 lab to a BSL- 3, work may be performed in the BSL-2 if it is performed in a BSC, only if: Risk assessment determines work can be done safely in a separate BSL-2 lab using BSL-3 practices and procedures. Both the BSC and the exhaust air from the room are vented to the outside of the building. The laboratory director approves the practice. 10

12 Beginning Your TB Risk Assessment - Tasks Perform a risk assessment to determine the risks for all tasks that are performed in your TB laboratory. My TB laboratory performs the following? A.) AFB processing and smear only. B.) AFB processing, smear, direct NAAT on AFB positive smears only. C.) AFB processing, smear, direct NAAT on AFB positive smears and full culture identification. D.) AFB processing, smear, direct NAAT on AFB positive smears, full culture and susceptibility testing. E.) Some other combination of tasks. 11

13 Which of the following is true regarding BSL-2 Enhanced Precautions? A) BSL-2 enhanced is used when an organism is isolated that would require a BSL-3 laboratory (such as Mtb) and there isn t a BSL-3 laboratory available. B) BSL-2 enhanced practices include controlling access to the immediate area C) BSL-2 enhanced practices include wearing additional PPE such as a solid-front gown, double gloves and a N-95 respirator D) BSL-2 enhanced practices include decontaminating all materials before removing from the hood and all waste before it leaves the facility. E) All of the above 12

14 Mitigating Risk : Engineering Controls Containment: Primary barriers designed to protect the laboratory worker (i.e. BSC, capped centrifuge carriers, clean and dirty sinks, hands-free sinks, sufficient air changes) Secondary barriers designed to protect those outside the laboratory(i.e. unidirectional airflow into the laboratory, exhaust air filtering, use of an anteroom) 13

15 Centrifuges Centrifuges have been associated with a number of LAIs low incidents but aerosols generated can contaminate the entire laboratory Critical to load, balance and operate according to manufacturers directions Requires proper maintenance, regular inspection, daily cleaning and at least monthly disinfection Should have lockable lids, sealed rotors or safety cups when used for infectious materials that are opened inside a BSC after centrifugation The centrifuge shouldn t be place inside the BSC because it may disrupt the laminar airflow of the BSC when in operation. If suspect tube breakage, do not open rotor lid or safety cups for 30 min. open in a BSC 14

16 Mitigating Risk : Administrative and Work Practice Controls Require strict adherence to SOPs. Provide training and perform yearly competency on employees. Require strict adherence to posted warning signs. BSC requirements: Monitor and document that the BSC is functioning properly Perform and document annual certification and cleaning Placement of BSC and training in the proper use of a BSC Keeping BSC free of clutter so functions properly and disinfect after use Work on towel soaked in disinfectant. Heat fix slides before removing from BSC. Disinfect all waste including liquid waste before removing from BSC and disposing of waste. Autoclave reusable gowns before laundering. Perform annual TB skin testing. Report and monitor all exposures. Wash hands before leaving room. 15

17 Mitigating Risk : Personal Protective Equipment N-95 Respirator or PAPR with N-95 Training and Annual Fit Testing/PAPR training and maintenance. Eligibility to participate in a respiratory program includes a medical evaluation and a pulmonary function test. Solid front disposable gown that closes in the back with snug (knit) cuffs. Gloves long enough to overlap the sleeves of the gown (double gloving is often preferred). Remove all PPE before exiting the laboratory. Caution: Self contamination most often occurs when doffing PPE improperly. 16

18 Summary While risk can never be zero due to the potential for human error, we can reduce the risk through risk assessment and the application of mitigation strategies to improve the culture of biosafety in our labs. Risk Assessment Mitigation strategies 17

19 Resources CDC: Biosafety in Microbiological and Biomedical Laboratories, 5 th Edition, CDC MMWR: Guidelines for Safe Work Practices in Human and Animal Medical Diagnostic Laboratories, Supplement, Vol. 61, January 6, CDC MMWR: Guidelines for Biosafety Laboratory Competency, Supplement, Vol. 60, April 15, CLSI: M29-A4 Protection of Laboratory Workers From Occupationally Acquired Infections ; Approved Guideline 4 th Edition, May 2014 ASM Press: Manual of Clinical Microbiology, 10 th Edition, Versalovic, J., Vol. 1,

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