Tuberculosis Intensive November 17 20, 2015 San Antonio, TX

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1 Tuberculosis Infection Prevention in Health Care Settings Jeffrey L. Levin, M.D., M.S.P.H. November 18, 2015 Tuberculosis Intensive November 17 20, 2015 San Antonio, TX EXCELLENCE EXPERTISE INNOVATION Jeffrey L. Levin, M.D., M.S.P.H. has the following disclosures to make: No conflict of interests No relevant financial relationships with any commercial companies pertaining to this educational activity 1

2 Tuberculosis Infection Prevention in Health Care Settings Jeffrey L. Levin, M.D., M.S.P.H.* for Heartland National TB Center *Department of Occupational Health Sciences, The University of Texas Health Science Center at Tyler Tuberculosis Intensive EXCELLENCE EXPERTISE INNOVATION Jeffrey L. Levin, M.D., M.S.P.H. has the following disclosures to make: No conflict of interests No relevant financial relationships with any commercial companies pertaining to this educational activity 2

3 Objectives To describe the components of an effective infection prevention program including: Administrative controls to reduce risk of exposure Environmental controls to prevent spread and reduce concentration of droplet nuclei Personal respiratory protection in areas with increased risk of exposure Infection prevention in the operating room References & Resource Materials CDC: Tuberculosis Infection Control and Prevention in Health Care Settings last accessed on at Centers for Disease Control and Prevention. Guidelines for preventing the transmission of Mycobacterium tuberculosis in Health Care Settings, MMWR Recommendations and Reports, December 30, 2005, Vol. 54, No. RR 17; last accessed on at NIOSH Workplace Safety & Health Topics: Tuberculosis web page last accessed on at National Institute for Occupational Safety and Health. NIOSH respiratory protection program in health care facilities. September 1999; DHHS (NIOSH) Publication No OSHA: Tuberculosis web page last accessed on at 3

4 Fundamentals of TB Infection Prevention Early identification Prompt airborne infection isolation Effective treatment of persons with active TB Guidance: Centers for Disease Control and Prevention. Guidelines for preventing the transmission of Mycobacterium tuberculosis in Health Care Settings, MMWR Recommendations and Reports, December 30, 2005, Vol. 54, No. RR 17; What is the most dangerous type of TB to Health Care Workers? The Unsuspected Patient with TB disease!! 4

5 Transmission of Tuberculosis Aerosol (airborne droplet nuclei) transmits infection 21 23% of close contacts become infected Patient factors Disease in lung, airway, and/or larynx Coughing or cough inducing procedure Concentration of droplet nuclei (cavitary>non cavitary). Sputum smear Positive: transmission occurs Negative, but culture positive: transmission less often Environmental factors Duration of contact Small enclosed space Poor ventilation or recirculation of room air Other factors Susceptibility of the host Poorly understood bacteria characteristics Infection rate drops rapidly with treatment initiation How long should patients be isolated? 5

6 Traditional CDC Isolation Recommendations Patients are not considered infectious if they meet the following criteria: Adequate therapy for 2 or 3 weeks Favorable clinical response Sputum smear negative x 3 (consecutive, 8 24 hours apart, at least one early morning) Disconnect: Recommendation vs. Reality Amended CDC Isolation Recommendations Many patients released from strict isolation after 2 3 weeks (cough resolved, energy improved, smear grade, pan-susceptible organism, contagion reduced) 6

7 Outpatient or Inpatient Therapy? Guiding principle: Minimize transmission risk Inpatient therapy guidelines: Is it worth putting more people at risk? Clinical indications (e.g., massive hemoptysis, concurrent disease complications) High risk for poor adherence to therapy Recognition of Infectiousness In general, patients who have suspected or confirmed TB disease should be considered infectious if they have disease in the lungs, airway, or larynx, or are coughing, or are undergoing cough inducing procedures, or have positive AFB sputum smears, And are not on anti tuberculosis chemotherapy, or have just started chemotherapy, or have a poor clinical or bacteriologic response to chemotherapy. 7

8 Environmental Factors that Enhance Probability of Transmission Exposure in small, enclosed spaces Inadequate local or general ventilation that results in insufficient dilution or removal of infectious droplet nuclei Recirculation of air containing infectious droplet nuclei Inadequate cleaning of equipment Agency Oversight for HCWs Advisory CDC 2005 Guidelines NIOSH and respirators Regulatory Federal OSHA State OSHA (where applicable) State public health agency for reporting Accreditation The Joint Commission 8

9 Overview of Scope Difference 2005 versus 1994 CDC Guidelines Applies to entire health care setting rather than selected areas Scope of settings broader: laboratories, more outpatient & non traditional settings 9

10 Airborne Infection Isolation (AII) All patients with confirmed drug susceptible TB disease should remain in AII while hospitalized until they: have had three consecutive, negative AFB sputum smear results collected in 8 24 hour intervals (at least one should be an early morning specimen as respiratory secretions pool overnight). Will generally allow patients with negative smear results to be released from airborne precautions in 2 days; demonstrate clinical improvement; and are on adequate anti TB chemotherapy. Continued isolation for those with multi drug resistant TB TB Infection Prevention Program and Three Level Hierarchy of Controls 10

11 Administrative Controls Primary strategy for infection prevention intended to reduce risk of exposing uninfected persons to persons who have infectious TB Administrative Controls Assigning responsibility for TB infection prevention Conducting a TB risk assessment Developing and instituting a written TB infection prevention plan Ensuring the timely availability of lab Implementing effective work practices and work assignments Ensuring proper cleaning/disinfection of equipment Training and education of HCWs Screening and evaluating HCWs Applying epidemiologic principles Coordinating efforts with state/local health departments 11

12 Administrative Controls TB infection prevention programs for settings where patients with suspected or confirmed infectious TB disease might be encountered (whether or not kept beyond initial assessment or care) TB risk assessment (CDC 2005, Appendix B) Community rate of TB disease Number of patients with TB disease presenting for care Timeliness of recognition, isolation, and evaluation Evidence for transmission of MTB in the setting Types and condition of environmental controls present in facility Annual risk assessment TB Screening for HCWs (CDC 2005 Appendix C) Baseline testing for M. tuberculosis infection Serial testing for M. tuberculosis infection Serial screening for signs or symptoms of TB disease exempt HCWs who have a documented history of a positive screening test result or adequate therapy for TB infection or disease, from further testing unless symptomatic TB training and education Two step TST versus blood analysis for MTB (BAMT/IGRA) strengths and weaknesses to be considered 12

13 Risk Classification to Determine Need for HCW TB Screening and Frequency* *CDC Guidelines, 2005 Environmental Controls Environmental controls (the second level of the hierarchy) prevent the spread and reduce the concentration of infectious droplet nuclei. Environmental controls include technologies for the removal or inactivation of M. tuberculosis. 13

14 Primary Controlling the source of infection by use of local exhaust ventilation (hoods, tents, or booths) Diluting and removing contaminated air by use of general ventilation Secondary Environmental Controls Controlling the airflow to prevent contamination of air in areas adjacent to the source (Airborne Infection Isolation rooms or AII) Cleaning the air by use of high efficiency particulate air (HEPA) filtration CDC guidelines recommend the use of ultraviolet germicidal irradiation (UVGI) only with the simultaneous use of HEPA filters and high rates of purge airflow Environmental Controls General Ventilation Special Issues Two types of general ventilation system Single pass (preferred) Recirculation (use of air cleaning technologies like HEPA filtration) Constant air volume preferred over variable air volume systems as negative pressure differential easier to maintain Negative pressure Achieved by exhausting air at higher volumetric rates of 12 air changes per hour (ACH) in new facilities (> 6 ACH for AII in existing facilities) Move air from less to more contaminated Ceiling to floor one option to reduce HCW exposure Importance of monitoring and regular maintenance 14

15 HEPA High efficiency particulate air filtration Minimum removal efficiency of 99.97% of particles > or = to 0.3 microns in diameter Room Air Flow Pattern Designed to Provide Mixing of Air CDC Guidelines,

16 An ante room is always recommended, as this provides a barrier between the TB Room and hallways and limits the impact of opening doors and traffic. Helps to maintain Negative Isolation. HEPA Filter Patient Room Ante room Monitoring Room Air Flow Continuous Monitor with Pressure Alarm From CDC Guidelines,

17 Special Situation: Operating Room (OR) Normal OR Airflow: OR Hallway Bacterial contamination of surgical field But Dissemination of TB from surgical field Measures to prevent TB dissemination in OR Administrative: Schedule patient with TB disease during low use period (few other patients/staff, extended time after case for air purification) Environmental: OR w/ ante room; Ante room air flow pressure negative to OR & hallway; >95% efficiency filter on expiratory port vent/anesthesia machine Respiratory Protection: Staff wear N95 mask Personal Respiratory Protection The third level of the hierarchy is the use of personal respiratory protection in situations that pose a relatively high risk for exposure. 17

18 Respiratory Protection Measures Implementing a respiratory protection program Training HCWs on respiratory protection Training patients on respiratory hygiene and cough etiquette procedures Respirators Sequence of Events 1994 CDC Guidelines 10/17/1997 OSHA published a proposed standard for occupational exposure to MTB (29 CFR ) Respirator usage for TB regulated by OSHA under 29 CFR and compliance policy directive (CPL) (Enforcement Procedures and Scheduling for Occupational Exposure to Tuberculosis) and CPL 2 254A (Respiratory Protection Program Guidelines) 12/31/2003 OSHA announced termination of rulemaking for a TB standard Respirator usage for TB now regulated under the general industry standard for respiratory protection (29 CFR ) Consolidated Appropriations Act for 2005 and 2006 none of the funds appropriated to administer or enforce Respirator Standard to require annual fit testing beyond initial testing Restrictions removed in 2008 see OSHA at =

19 When Should Personal Respiratory Protection be Used? Entering areas in which patients with suspected or confirmed infectious TB disease are being isolated Present during cough inducing or aerosol generating procedures performed on patients with suspected or confirmed infectious TB disease In other settings where administrative and environmental controls are not likely to protect them from inhaling infectious airborne droplet nuclei While conducting aerosol producing procedures Respirator Program Steps (NIOSH) Conduct a TB risk assessment Select respirators Write Standard Operating Procedures (SOPs) Medically screen all users Provide training User seal check, fit test, and issue respirators Inspect, clean, maintain, and store respirators Evaluate the program 19

20 Respirator Selection Criteria for MTB At least N 95 particulate filter respirators certified by the National Institute for Occupational Safety and Health (NIOSH) should be used and is adequate in most situations Ability to adequately fit respirator wearers who are included in a formal respiratory protection program Ability to fit the different facial sizes and characteristics of health care workers. This can usually be met by making respirators available in different sizes In selecting respirator models, give preference to models shown by their manufacturers to have inherently well fitting characteristics OSHA s Respiratory Protection Standard 29 CFR

21 Filtering Face Piece A negative pressure particulate respirator with a filter as an integral part of the face piece or with the entire face piece composed of the filtering medium. Meets the CDC/NIOSH criteria for N95. Also includes other higher efficiency (99 and 100) models and different (P and R) mask materials. Classes of Non powered Air Purifying Particulate Filters Nine classes: three levels of filter efficiency, each with three categories of resistance to filter efficiency degradation due to the presence of oil aerosols N 95, 99, 100 ; N for Not resistant to oil R 95, 99, 100 ; R for Resistant to oil P 95, 99, 100 ; P for oil Proof 21

22 Powered Air Purifying Respirator (PAPR) An air purifying respirator that uses a blower to force the ambient air through air purifying elements to the inlet covering. Physician or Other Licensed Health Care Professional (PLHCP) An individual whose legally permitted scope of practice (i.e., license, registration, or certification) allows him/her to independently provide, or be delegated the responsibility to provide, some or all of the health care services required by paragraph (e), Medical evaluation. 22

23 Medical Evaluation: Procedures Must provide a medical evaluation to determine employee s ability to use a respirator, before fit testing and use Must identify a PLHCP to perform medical evaluations using a medical questionnaire or an initial medical examination that obtains the same information Medical evaluation must obtain the information requested by the questionnaire in Sections 1 and 2, Part A of App. C of the OSHA Standard Follow up medical examination is required for an employee who gives a positive response to any question among questions 1 through 8 in Section 2, Part A of App. C or whose initial medical examination demonstrates the need for a follow up medical examination Medical Evaluation Additional Medical Evaluations Annual review of medical status is not required At a minimum, employer must provide additional medical evaluations if: Employee reports medical signs or symptoms related to the ability to use a respirator PLHCP, supervisor, or program administrator informs the employer that an employee needs to be reevaluated Information from the respirator program, including observations made during fit testing and program evaluation, indicates a need Change occurs in workplace conditions that may substantially increase the physiological burden on an employee 23

24 Fit Testing Before an employee uses any respirator with a negative or positive pressure tight-fitting face piece, the employee must be fit tested with the same make, model, style, and size of respirator that will be used annual testing and training. Qualitative Fit Test (QLFT) A pass/fail fit test to assess the adequacy of respirator fit that relies on the individual s response to the test agent. Agents prescribed in Appendix A in OSHA Regulations Isoamyl Acetate Saccharin Sodium Denatonium Benzoate (Bitrex ) Stannic Chloride (Irritant smoke) Rainbow passage 24

25 Quantitative Fit Test (QNFT) An assessment of the adequacy of respirator fit by numerically measuring the amount of leakage into the respirator. (Rainbow passage) User Seal Check An action conducted by the respirator user to determine if the respirator is properly seated to the face. Positive Pressure Check Negative Pressure Check 25

26 Concluding Observations TB incidence in community & hospitals is decreasing, though resistant organisms have increased Risk to health care workers is decreasing ( but Risk for increased complacency!) What is the correct sequence for the application of control measures in a tuberculosis exposure prevention program? A. Administrative, Engineering, Respiratory Protection B. Respiratory Protection, Administrative, Engineering C. Engineering, Respiratory Protection, Administrative D. The sequence makes no difference E. None of the above Test Your Knowledge Question #1 26

27 What is the correct sequence for the application of control measures in a tuberculosis exposure prevention program? A. Administrative, Engineering, Respiratory Protection B. Respiratory Protection, Administrative, Engineering C. Engineering, Respiratory Protection, Administrative D. The sequence makes no difference E. None of the above Test Your Knowledge Question #1 Answer Test Your Knowledge Question #2 Appropriate administrative measures include: A. Conducting a TB risk assessment B. Testing and evaluating health care workers who are at risk for TB or may be exposed to TB C. Controlling the source of infection by use of local exhaust ventilation D. Diluting and removing contaminated air by use of general ventilation 27

28 Test Your Knowledge Question #2 Answer Appropriate administrative measures include: A. Conducting a TB risk assessment B. Testing and evaluating health care workers who are at risk for TB or may be exposed to TB C. Controlling the source of infection by use of local exhaust ventilation D. Diluting and removing contaminated air by use of general ventilation Test Your Knowledge Question #3 Personal respirators should be used in settings where administrative and environmental controls may not fully protect health care workers from infectious droplet nuclei. A. True B. False 28

29 Test Your Knowledge Question #3 Answer Personal respirators should be used in settings where administrative and environmental controls may not fully protect health care workers from infectious droplet nuclei. A. True B. False Questions? Thank You 29