PLAN FOR THE PREVENTION OF TRANSMISSION OF TUBERCULOSIS
UNIVERSITY OF ALABAMA
OFFICE OF ENVIRONMENTAL HEALTH AND SAFETY
AUGUST, 1996
TABLE OF CONTENTS
Preface
I. Introduction
II. Exposure Control
III. Methods of Compliance
Glossary
Attachment A - Risk Appraisal Survey
Attachment B - Model Exposure Control Plan
Attachment C - PPD skin Test Consent Form
Figure 1
Figure 2
PREFACE
The Plan For the Prevention of Transmission of Tuberculosis has been developed as a basic guideline to aid departments and individuals in their development of protective measures to reduce the risk of transmitting TB in U of A health-care facilities. The formulation of the plan is based on federal regulations and CDC guidelines available from the Office of Environmental Health and Safety (EHS).
As an initial step, each department/area supervisor in a health-care facility should evaluate the risk of TB exposure for all health-care workers (HCW). Supervisors should document their assessments of the level of exposure associated with job titles. Supervisors shall be responsible for developing an exposure control plan (using the model presented in these guidelines) for any employees within their jurisdiction who are at risk of TB exposure.
The Office of EHS will serve to assist with risk assessment determination and the implementation of exposure control plans.
I. INTRODUCTION
In recent years, TB has become a rapidly spreading disease that has brought about new federal regulations, strict public health codes and concern among health-care workers and risk managers. Once thought to be nearly eradicated, TB and new strains of drug-resistant Mycobacterium tuberculosis have emerged in at least 40 states.
Tubercle bacilli are transmitted in airborne droplets that are generated when people with active TB disease of the lungs or air passages cough, sneeze, speak, spit, or sing. These very small droplets (1-5 u) remain airborne for extended periods of time in normal air currents, easily spreading throughout the environment. Whenever the airborne droplets of TB bacteria are inhaled deep into the lungs of a person, the result is infection of the alveoli. From these tiny air sacs, the TB infection can spread to various organs and tissues.
The probability of becoming infected with TB depends on the concentration of TB infected airborne particles, the duration of exposure and the immune state of those persons exposed. In people with a normal immune system, the body's natural defenses control the infection within 2-10 weeks. However, for people who are immuno-compromised, the threat of TB transmission is increased. Transmission of Mycobacterium tuberculosis infection to persons with HIV infection, young children and the elderly is of particular concern because their risk of developing active TB if infected is considerably higher than the general population. Thus, health-care facilities should be particularly alert to the need for preventing TB transmission wherever persons with these risk factors receive care or work.
The University of Alabama Plan For the Prevention of Transmission of TB shall employ the following control measures: (1) the use of administrative measures to reduce the risk of exposure to active TB; (2) the use of engineering controls to prevent the spread and reduce the concentration of infectious airborne droplets and (3) the use of personal respiratory protective equipment by persons working on tasks that subject them to the risk of TB infection exposure.
II. EXPOSURE CONTROL
Research indicates that health-care facilities are often at high risk of TB transmission. Included among those affected are medical staff, lab and x-ray personnel, some receptionists and others. The risk may be higher in areas where health-care providers encounter patients with TB before diagnosis or treatment or in areas where high hazard procedures are executed. Examples of high-hazard procedures include:
* Aerosolized medication treatment
* Sputum induction
* Bronchoscopy or endotracheal intubation
* Suctioning procedures
* Procedures that stimulate coughing.
Any HCW whose normal routine involves high-hazard procedures, is automatically considered to be at a minimum at the "intermediate" risk level.
A. Step 1: Identifying employee's risk to TB transmission. (Figure 1)
Between July-August each year, designated representatives of each U of A health-care facility will be responsible for conducting risk appraisal surveys within their area of supervision to identify and classify all employee's risk to TB transmission. This survey will be conducted using a survey form (Attachment A) that is developed and revised as appropriate. The designated representative will evaluate all physical areas and worker activities on the basis of job descriptions and classify areas and job titles according to risk of TB exposure. Classification of risk as minimal, very low, low, intermediate, and high in a specific area and for a specific occupational category shall be based on (1) the profile of TB in the community,(2) the number of infectious TB patients admitted to the area or the estimated number of infectious TB patients to whom health-care workers (HCW) in an occupational category may be exposed, and (3) on the results of analysis of health-care workers' Purified Protein Derivative (PPD) skin test conversions and possible patient-to-patient TB transmission. The initial step for risk evaluation is to require and provide the means for all HCWs to receive Tuberculin PPD skin tests. The index of suspicion for infectious TB among patients, the frequency of HCW skin testing, the number of TB isolation rooms and other factors will vary according to the risk of TB transmission in the facility, area or occupational group. Risk assessment should be conducted by a qualified person or group of persons, should be conducted for the entire facility and for specific areas within the facility and in addition, should be conducted for groups of HCWs who work throughout the facility rather than in a specific area. A profile of TB in the community that is served by the facility should be obtained from the public health department. This profile should include the incidence of active TB in the community and the drug-susceptibility patterns of M. tuberculosis isolates from patients in the community. In Risk Assessment, a positive response to any single criteria within each category, automatically designates risk at that level. These risk groups are defined as:
"MINIMAL" - applies only to an entire facility. A "minimal-risk" facility does not admit TB patients to inpatient or outpatient areas and is not located in a community with TB.
"VERY LOW" - a facility in which (a) patients with active TB are not admitted to inpatient areas but may receive initial assessment and diagnostic evaluation or outpatient management in outpatient areas (e.g. emergency areas) and (b) patients who may have active TB and need inpatient care are promptly referred to a collaborating facility. The "very low-risk" category may also be appropriate for outpatient facilities that do not provide initial assessment of persons who may have TB, but do screen patients for active TB as part of a limited medical screening before undertaking specialty care (e.g., dental settings).
"LOW" - It includes those areas or occupational groups in which:
(1) the PPD skin test conversion rate is not greater than that for areas or groups in which occupational exposure for M. tuberculosis is unlikely or than previous conversions rates for the same area or group.
(2) there are no clusters of PPD test conversions;
(3) there is no evidence of person-to-person transmission of M. tuberculosis.
(4) there are fewer than 6 TB patients examined or treated per year.
"INTERMEDIATE" - It includes those areas or groups in which:
(1) the PPD test conversion rate is not greater than that for areas or groups in which occupational exposure to M. tuberculosis is unlikely or than previous conversion rates for the same area or group,
(2) there are no clusters of PPD test conversions.
(3) there is no evidence of person-to-person transmission of M. tuberculosis.
(4) there are greater than or equal to 6 active TB patients examined or treated per year.
"HIGH" - those areas or occupational groups in which:
(1) the effects of high hazard procedures pose potential exposures
(2) the PPD test conversion rate is significantly greater than for areas or groups in which occupational exposure to M. tuberculosis is unlikely or than previous conversion rates for the same area or group;
(3) there is a cluster of PPD test conversions, and epidemiologic evaluation suggests nosocomial transmission of M. tuberculosis.
(4) there is evidence of person-to-person transmission of M. tuberculosis.
Upon request, a staff member from the U of A Office of EHS will meet with those individuals charged with completing the surveys in order to provide guidance and assistance. The completed surveys will be returned to the Office of EHS for review and comment.
Based on the results of the risk assessment, a written TB infection-control plan should be developed and implemented for each area of the facility and for each occupational group of HCWs not assigned to a specific area of the facility. Health-care facilities are likely to have a combination of low-, intermediate-, and high- risk areas or occupational groups during the same time period. The appropriate protocol should be implemented for each area or group. Areas in which cough-inducing procedures are performed on patients who may have active TB should, at the minimum, implement the intermediate-risk protocol.
B. Step 2 - Develop a specific Exposure Control Plan for each department/area within the health-care facility and for occupational groups not assigned to a specific area.
Written exposure control plans shall be developed by each Administrative Unit in which there are employees at risk for occupational exposure to TB transmission. The plan should be individualized for each Administrative Unit. The model plan available from the Office of EHS (or in Attachment B of this policy) may be used as a guideline in developing each individual plan.
a. Risk Appraisal Survey (Attachment A) which contains the following:
(1) For each area of the facility, compile a list of all job classifications and indicate the level of risk for TB transmission assessed for that specific job description.
(2) A list of all tasks and procedures in which occupational exposure to TB occurs and that are performed by employees at respective hazard levels.
(3) Exposure determination shall be made without regard to the use of personal protective equipment.
b. Methods of compliance with the plan including schedules for implementing and maintaining the compliance procedures.
c. Method of accomplishing Tuberculin skin tests (purified protein derivative) for all employees who work in a health-care facility.
d. Response to employees who demonstrate a positive PPD skin test.
e. Response to employees who demonstrate a positive test after having previously had a negative test. This constitutes a "conversion".
f. Method of communication of hazards to employees.
g. Method of record-keeping as required by this Policy.
h. Methods for providing information and training.
2. The Exposure Control Plans should be submitted for review to the Director of the Office of EHS by November 1 following the July-August risk appraisal.
3. The Plans should be reviewed annually by the supervisor in each Administrative Unit who is designated as having responsibility for implementing this policy.
4. At any time when an employee assumes responsibilities that would place them at risk for exposure, all the exposure control procedures in the Plan shall apply.
5. A copy of the Exposure Control Plan shall be accessible in the work place to all employees at risk for occupational exposure.
6. All provisions of the Exposure Control Plan shall be applicable immediately from the time an employee assumes his/her duties.
III. METHODS OF COMPLIANCE
A. Administrative
The TB control program is based on a hierarchy of control measures. Of highest priority is the use of administrative measures to reduce the risk of exposure to persons with infectious TB. This includes developing and implementing effective written policies to ensure the rapid detection, isolation, diagnostic evaluation and treatment of persons likely to have TB, as well as implementing effective work practices by persons working in the health-care facility.
1. Early identification and treatment of persons with TB infection.
The tuberculin skin test is the only method currently available that demonstrates infection with M. tuberculosis in the absence of active TB. Persons at increased risk of TB (e.g. the very young/old or immunocompromised) or for whom the consequences of TB may be especially severe, should be screened for TB infection to identify those for whom preventive treatment is indicated.
2. Early identification and treatment of persons with active TB.
An effective means of preventing tuberculosis transmission is preventing the generation of infectious droplet nuclei by persons with infectious TB. This can be accomplished by early identification, isolation and treatment of persons with active TB. A diagnosis of TB should be considered for any patient with persistent cough or other symptoms compatible with TB, such as weight loss, anorexia or fever. Diagnostic measures should include a medical history, physical exam, tuberculin skin test, chest radiograph and microscopic examination and culture of sputum or other appropriate specimen. The need for other diagnostic methods may be indicated. The probability of TB is increased by finding a positive reaction to a tuberculin skin test or a history of a positive skin test, a history of previous tuberculosis, membership in a group at high risk for TB or a history of exposure to TB. Active TB is strongly suggested if the diagnostic evaluation reveals Acid-fast Bacilli (AFB) in sputum, a chest radiograph is suggestive of TB or the person has symptoms highly suggestive of TB.
3. Determining infectiousness of TB patients.
The infectiousness of a person with TB correlates with the number of organisms that are expelled into the air, which in turn, correlates with the following factors:
(a) anatomic site of disease
(b) presence of cough or other forceful expirational maneuvers
(c) presence of AFB in the sputum smear
(d) willingness or ability of the patient to cover his/her mouth when coughing
(e) presence of cavitation on chest radiograph
(f) length of time the patient has been on adequate chemotherapy
(g) duration of symptoms
(h) procedures that enhance coughing e.g. sputum induction.
Infectiousness is greatest among patients who have a productive cough, pulmonary cavitation on chest radiograph and AFB on sputum smear. Infection is more likely to result from exposure to a person who has unsuspected pulmonary TB and who has not received anti-tuberculosis therapy or from a patient who is not receiving adequate therapy, because of patient noncompliance or the presence of drug-resistant organisms. Administering effective anti-tuberculosis medications has been shown to be strongly associated with a decrease in infectiousness among persons with TB. In general, persons suspected of having active TB and persons with confirmed TB should be considered infectious if cough is present, if cough-inducing procedures are performed or if sputum smears are known to contain AFB, and if these patients are not on chemotherapy, have just started chemotherapy or have a poor clinical or bacteriologic response to chemotherapy. Most TB experts agree that noninfectiousness in pulmonary TB can be established by finding sputum free of AFB by smear examination on three consecutive days for a patient on effective chemotherapy. Even after isolation precautions have been discontinued, caution should be exercised when a patient with TB is placed in a room with another patient, especially if the other patient is immunocompromised.
B. Engineering and source controls:
The second level of the hierarchy is the use of engineering controls to prevent the spread and reduce the concentration of infectious droplet nuclei. See Supplement 1 for detailed information regarding specific engineering controls for specific situations. Controls for areas involving high risk of TB transmission include the following:
C. Personal Respiratory Protective Equipment
Administrative and engineering controls minimize the number of areas in the health-care facility where exposure to infectious TB may occur, and they reduce, but do not eliminate the risk in those few areas (e.g. TB isolation rooms and treatment rooms where cough-inducing procedures are performed) where exposure may still occur. However, since persons entering isolation and treatment rooms may be exposed to M. tuberculosis, the third level of hierarchy needed is the use of personal respiratory protective equipment to further reduce exposure in these areas. The respiratory protective devices used in these settings should have characteristics that are suitable for the organism they are protecting against and the settings in which they are used. Respiratory protective devices used in health-care settings for protection against M. tuberculosis should meet the following standard criteria:
1. The ability to filter particles 1 um in size in the unloaded state with a filter efficiency of >95%(i.e., filter leakage of <5%), given flow rates of up to 50L per min.
2. The ability to be qualitatively or quantitatively fit tested in a reliable way to obtain a face-seal leakage of <10%.
3. The ability to fit the different facial sizes and characteristics of HCWs, which can usually be met by making the respirators available in at least three sizes.
4. The ability to be checked for facepiece fit by HCWs each time they put on their respirators.
* Masks must be worn by HCWs entering isolation and treatment rooms where there is potential exposure to M. tuberculosis.
* Masks must be worn during all high-hazard procedures (e.g. sputum induction, suctioning, intubation, bronchoscopy, autopsy and administration of aerosol medications).
* All respiratory protective devices used in the workplace must be certified by NIOSH and approved by EHS. The NIOSH certification procedures have recently been revised. Effective July 10, 1995, several new classes of air-purifying, particulate respirators (PR) may be used instead of respirators with HEPA filters.
* Each mask must be custom fitted to the individual who will wear it.
* The fit must be tested by a qualified party i.e. an industrial hygienist.
Those facilities that do not have isolation rooms for TB, that do not perform cough-inducing procedures and refer all potential TB patients, need NOT have a respirator program. Such facilities must perform a periodic risk assessment, have protocols for referral, and an infection control plan that is periodically reviewed.
RESPIRATORY PROTECTION PROGRAM
POLICY -in the control of the occupational/infectious diseases caused by breathing air contaminated with gases, aerosols or infectious agents, the primary objective is to prevent harmful exposures. This is accomplished as far as feasible by accepted engineering control measures (e.g. ventilation, cautious work practices). When engineering controls are not feasible, or while they are being instituted, appropriate respirators may be required. The U of A Respiratory Protection Plan is available through the Office of EHS.
PROCEDURE
1. RESPONSIBILITY
(a) The Office of Environmental Health and Safety will be responsible for:
(1) Determining the ability of HCW to wear a respirator.
(2) Implementing fit-testing and training programs.
(3) Annual evaluation of the respiratory protection programs.
(4) Surveillance of work area conditions.
(5) Approval of respirators for use.
(b) Supervisor Personnel are responsible for:
(1) Ensuring that respirators are available as needed and at no cost to employees.
(2) Ensuring that employees wear respirators as required.
(3) Ensuring that employees receive initial and on-going training on the use of and need for respirators.
(4) Maintaining health and medical surveillance records.
(c) Employees are responsible for:
(1) Using the respirator supplied to him/her in accordance with the instructions and training.
(2) Reporting a respirator malfunction or defect to the supervisor.
(3) Participating in mandatory fit-testing, in-services and medical surveillance as required by the employer.
(a) Medical Surveillance
(1) is used to evaluate an employee's ability to function while wearing a respirator.
(2) is required for any employee required to work in an area where respirators are worn.
(3) is to be performed prior to wearing a respirator.
(4) will include a questionnaire and physical exam.
(5) is the responsibility of and documented by the dept./area supervisor.
(6) is provided at no cost to the employee.
(b) Fit-Testing
(1) is used to evaluate the face to face-piece seal of the respirator, assuring the optimum performance from the respirator.
(2) is used to evaluate the face to face-piece seal of the respirator, assuring the optimum performance from the respirator.
(3) is to be performed after medical surveillance information is completed, prior to wearing a respirator and annually thereafter.
(4) will not be performed on HCW when conditions prevent a good face seal. Such conditions may include a beard or sideburns, absence of one or both dentures or facial deformity.
(c) Respirator Training is required prior to or at the time of initial job assignment and annually thereafter. It must include:
(1) information about the nature and extent of the hazard which necessitates respiratory protection;
(2) an explanation of why engineering controls may not be adequate to eliminate the need for personal respiratory protection;
(3) an explanation of why a particular type of respirator has been selected for a particular use;
(4) an explanation of the operation, capabilities and limitations of the respirator provided;
(5) instruction in how the respirator should be inspected, worn, checked for proper fit, stored and disposed of or maintained and cleaned, if appropriate;
(6) instruction in how to recognize an inadequately functioning respirator.
A health-care facility's risk assessment may identify a limited number of selected settings (e.g., bronchoscopy performed on patients suspected of having TB) where the estimated risk for transmission of M. tuberculosis may be such that a level of respiratory protection exceeding the standard criteria is appropriate.
D. Worker training and counseling
HCWs must have completed TB training before they are assigned to a position that involves the risk of exposure and annually thereafter. Workers must understand the risk, the protective measures in place and how to work safely to avoid exposure to TB. The training must be appropriate to the worker's risk. For example, training for nurses and dietary aids would cover the same topics but in different depth.
Counseling is to be available for workers with immune-system deficiencies or medical conditions that may lead to impaired immunity, those at risk for HIV infection and those with PPD test conversions. These workers should be counseled about optimizing safety practices, the risks associated with caring for patients with infectious diseases, and possible alternative job assignments.
(1) TB training and counseling is the responsibility of the dept./area supervisor.
(2) Documentation of annual TB training for all HCWs is the responsibility of the dept./area supervisor.
(3) TB training shall include:
(a) Concepts of TB transmission, pathogenesis and diagnosis.
(b) The difference between TB infection and active TB disease.
(c) Symptoms of TB.
(d) The possibility of reinfection in persons with a positive PPD test.
(e) The potential for exposure to TB in the facility.
(f) Situations with increased risk of exposure to TB.
(g) A hierarchy of TB control measures.
(h) The facility's written TB infection-control plan.
(i) The purpose of PPD skin testing for TB and the significance of PPD test results.
E. Worker medical screening and follow-up
Skin testing to detect TB infection using the Mantoux PPD test is a critical component of HCW protection.(see Figure 2) All HCWs should be tested at the time of employment and at least annually thereafter. A positive skin test indicates the presence of TB infection or TB disease or previous vaccination with BCG (used in developing countries but not generally in the U.S.)
If a HCW is exposed to TB, he/she must report the exposure to the dept./area supervisor and then be referred for medical evaluation. Exposure is defined as "potential exposure to the exhaled air of an individual with suspected or confirmed TB disease" without the protection of a respirator.
Evaluation shall include details of the exposure, a baseline PPD skin test and a follow-up PPD skin test 12 weeks later. Evaluation and any further treatment shall be provided at no cost to HCW.
Any HCW with persistent cough, especially in the presence of other symptoms or signs compatible with TB, will be evaluated promptly for TB. The HCW will not return to work until TB is excluded or the HCW is on therapy and documented to be noninfectious.
F. Worker medical treatment
All HCWs with newly recognized positive PPD tests or PPD test conversions will be promptly evaluated for clinically active TB. Those HCWs determined to be without active TB should be evaluated for preventive therapy. HCWs with TB infection, but not active TB, may be allowed to continue their work routines.
If HCWs have active TB of the lungs or airway, they are to be restricted from working until they are no longer infectious. Criteria for return to work include three consecutive daily sputum smears that test negative for TB, the absence of coughing and a faithful adherence to the anti-TB medication therapy.
G. Coordination with the Public Health Department
As soon as a patient or HCW is known or suspected to have active TB, the patient or HCW should be reported to the public health department so that appropriate follow-up can be arranged and a community contact investigation can be performed.
H. Recommendations specific for Medical Offices
In general, the symptoms of active TB are symptoms for which patients are likely to seek treatment in a medical office. Furthermore, the populations served by some medical offices, or the HCWs in the office, may be at relatively high risk for TB. Thus, it is likely that infectious TB will be encountered in a medical office. Because of the potential for M. tuberculosis transmission, the following recommendations should be observed:
* A risk assessment should be conducted at least annually, and TB infection-control policies based on results of the risk assessment should be developed for the medical office. The policies should include provisions for identifying and managing patients who may have undiagnosed active TB; managing patients who have active TB; and educating, training, counseling and screening HCWs.
* Patients with a medical history and symptoms suggestive of active TB should receive and appropriate diagnostic evaluation for TB and be evaluated promptly for possible infectiousness.
* Medical offices that provide evaluation or treatment services for TB patients should follow the recommendations for managing patients in ambulatory-care settings.
* If cough-inducing procedures are to be administered in a medical office to patients who may have active TB, appropriate precautions should be followed.
* Any HCW who has a persistent cough, especially in the presence of other signs or symptoms compatible with active TB should be evaluated promptly for TB. Such HCWs should not return to the workplace until a diagnosis of TB has been excluded or until they are on therapy and a determination has been made that they are noninfectious.
* HCWs who work in medical offices in which there is a likelihood of exposure to patients who have infectious TB should be included in employer-sponsored education, training, counseling and PPD testing programs appropriate to the level of risk in the office.
GLOSSARY
ADHERENCE Refers to the behavior of patients when they follow all aspects of the treatment regimen as prescribed by the medical provider, and also refers to the behavior of HCWs and employers when they follow all guidelines pertaining to infection control.
AEROSOL The droplet nuclei that are expelled by an infectious person (e.g., by coughing or sneezing); these droplet nuclei can remain suspended in the air and can transmit M. tuberculosis to other persons.
AFB Acid-Fast Bacilli - organisms that retain certain stains, even after being washed with acid alcohol. Most are mycobacteria. When seen on a stained smear of sputum or other clinical specimen, a diagnosis of tuberculosis should be considered.
ALVEOLI The small air sacs in the lungs that lie at the end of the bronchial tree; the site where carbon dioxide in the blood is replaced by oxygen from the lungs and where TB infection usually begins.
AIDS Acquired Immune Deficiency Syndrome
BCG Bacillus of Calmette and Guerin vaccine; A TB vaccine used in many parts of the world, other than the U.S.
BRONCHOSCOPY A procedure for examining the respiratory tract that requires inserting an instrument through the mouth or nose and into the trachea.
CHEMOTHERAPY Treatment of an infection or disease by means of oral or injectable drugs.
CLUSTER Two or more PPD skin-test conversions occurring within a 3 month period among HCWs in a specific area or occupational group, and epidemiologic evidence suggests occupational transmission.
CONTACT A person who has shared the same air with a person who has infectious TB for a sufficient amount of time to allow possible transmission of M.tuberculosis.
CULTURE The process of growing bacteria in the lab so that organisms can be identified.
DROPLET NUCLEI Microscopic particles (i.e., 1-5um in diameter) produced when a person coughs, sneezes, shouts, or sings. The droplets produced by an infectious TB patient can carry tubercle bacilli and can remain suspended in the air for prolonged periods of time and be carried on normal air currents in the room.
DRUG RESISTANCE, ACQUIRED A resistance to one or more anti-TB drugs that develops while a patient is receiving therapy and which usually results from the patient's non-adherence to therapy or the prescription of an inadequate regimen by a health care provider.
DRUG RESISTANCE, PRIMARY A resistance to one or more anti-TB drugs that exists before a patient is treated with the drug. Primary resistance occurs in persons exposed to and infected with a drug-resistant strain of M. tuberculosis.
DRUG SUSCEPTIBILITY PATTERN The anti-TB drugs to which the tubercle bacilli cultured from a TB patient are susceptible or resistant based on drug susceptibility tests.
DRUG SUSCEPTIBILITY TESTS Lab tests that determine whether tubercle bacilli cultured from a patient are susceptible or resistant to various anti-TB drugs.
EXPOSURE the condition of being subjected to something(e.g., infectious agents) that could have a harmful effect.
HCW Health Care Worker - Any health-care facility employee who has contact with patients or must access patient care areas as part of his/her occupational responsibility.
HEPA High Efficiency Particulate Air filter - A specialized filter that is capable of removing 99.97% of particles > 0.3 um in diameter and that may assist in controlling the transmission of M. tuberculosis.
HIV Human Immunodeficiency Virus - the virus that causes AIDS
IMMUNOSUPPRESSED A condition in which the immune system is not functioning normally. Immunosuppressed persons are at greatly increased risk for developing active TB after they have been infected with M. tuberculosis.
INDURATION An area of swelling produced by an immune response to an antigen. In tuberculin skin testing the diameter of the indurated area is measured 48-72 hrs. after the injection, recorded in millimeters.
INFECTIOUS Capable of transmitting infection.
INTERMITTENT THERAPY Therapy administered either two or three times per week, rather than daily.
MANTOUX TEST A method of skin testing that is performed by injection 0.1 mL of PPD-tuberculin containing 5 tuberculin units into the dermis of the forearm with a needle and syringe.
MULTIDRUG-RESISTANT TUBERCULOSIS Active TB caused by M. tuberculosis organisms that are resistant to more than one anti-TB drug; in practice, often refers to organisms that are resistant to both INH and rifampin with or without resistance to other drugs.
M. TUBERCULOSIS COMPLEX A group of closely related mycobacterial species that can cause active TB.
NEGATIVE PRESSURE The relative air pressure difference between two areas in a Health-care facility. A room that is at negative pressure has a lower pressure than adjacent areas, which keeps air from flowing out of the room and into adjacent rooms or areas.
NOSOCOMIAL An occurrence, usually and infection, that is acquired in a hospital or as a result of medical care.
PATHOGENICITY The quality of producing or the ability to produce pathologic changes or disease.
POSITIVE PPD REACTION A reaction to the PPD tuberculin skin test that suggests the person tested is infected with M. tuberculosis.
PR A disposable, Particulate Respirator (respiratory protective device) that is designed to filter out particles 1-5 microns in diameter.
PREVENTIVE THERAPY Treatment of latent TB infection used to prevent the progression of latent infection to clinically active disease.
PURIFIED PROTEIN DERIVATIVE tuberculin test A method used to evaluate the likelihood that a person is infected with M. tuberculosis.
PURIFIED PROTEIN DERIVATIVE tuberculin test conversion A change in PPD test results from negative to positive.
RESISTANCE The ability of some strains of bacteria, including M. tuberculosis, to grow and multiply in the presence of certain drugs that ordinarily kill them.
SPUTUM INDUCTION A method used to obtain sputum from a patient who is unable to cough up a specimen spontaneously.
TB CASE A particular episode of clinically active TB. Term should be used only to refer to the disease itself, not the patient.
TB INFECTION A condition in which living tubercle bacilli are present in the body but the disease is not clinically active. Infected persons usually have positive tuberculin reactions, but they have no symptoms related to the infection and are not infectious.
TRANSMISSION The spread of an infectious agent from one person to another.
TUBERCULOSIS A clinically active, symptomatic disease caused by an organism in the M. tuberculosis complex.
ULTRAVIOLET GERMICIDAL IRRADIATION (UVGI) The use of ultraviolet radiation to kill or inactivate microorganisms.
VIRULENCE The degree of pathogenicity of a microorganism as indicated by the severity of the disease produced and its ability to invade the tissues of a host.
ATTACHMENT A
RISK APPRAISAL SURVEY
TB EXPOSURE CONTROL
Facility___________________________ Department_______________________
Name of Supervisor Completing Form ______________________________________
One purpose of this survey is to identify job classifications and personnel within your Administrative Unit which are at risk for occupational transmission of tuberculosis (TB). Please list each Health Care Worker (see HCW definition in glossary) in your area in one of the three designated risk categories - Low, Intermediate or High. These risk categories are defined as:
"LOW" - It includes those areas or occupational groups in which:
(1) the PPD skin test conversion rate is not greater than that for areas or groups in which occupational exposure for M. tuberculosis is unlikely or than previous conversions rates for the same area or group.
(2) there are no clusters of PPD test conversions;
(3) there is no evidence of person-to-person transmission of M. tuberculosis.
(4) there are less than 6 TB patients examined or treated per year.
"INTERMEDIATE" - It includes those areas or groups in which:
(1) the PPD test conversion rate is not greater than that for areas or groups in which occupational exposure to M. tuberculosis is unlikely or than previous conversion rates for the same area or group,
(2) there are no clusters of PPD test conversions.
(3) there is no evidence of person-to-person transmission of M. tuberculosis.
(4) there are greater than or equal to 6 active TB patients examined or treated per year.
"HIGH" - those areas or occupational groups in which:
(1) the effects of high hazard procedures pose potential exposures.
(2) the PPD test conversion rate is significantly greater than for areas or groups in which occupational exposure to M. tuberculosis is unlikely or than previous conversion rates for the same area or group;
(3) there is a cluster of PPD test conversions, and epidemiologic evaluation suggests nosocomial transmission of M. tuberculosis.
(4) there is evidence of person-to-person transmission of M. tuberculosis.
HEALTH CARE WORKERS
Facility___________________________ Department________________ Phone # _________
|
Name |
Job Title |
Risk Level |
Procedure/Situation that places HCW at risk. |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
List all employees (HCWs and non-HCWs) in your area who are not assessed at Low, Intermediate or High risk levels.
|
Name |
Job Title |
Justification |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
A second purpose of the Risk Appraisal Survey is to identify those specific sites in your Administrative Unit in which the exposure to TB transmission is at "High" risk. These would include TB isolation and treatment areas as well as any area where High Hazard Procedures are performed.
SITE APPRAISAL
Facility___________________________ Department________________ Phone # __________
|
Unit |
Room # |
Utilization Description |
High Risk |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Return all Risk Appraisal forms by November 1, to the Office of Environmental Health and Safety, Box 870178. Upon request, a staff member from the U of A Office of EHS will meet with those individuals charged with completing the surveys in order to provide guidance and assistance.
ATTACHMENT B
MODEL EXPOSURE CONTROL PLAN
(This is intended to be used only as a guideline in completing each individual exposure control plan.)
In the interest of preventing the transmission of M. tuberculosis, the University of Alabama has established a policy of employee protection and workplace safety. This Exposure Control Plan has been prepared in accordance with CDC Guidelines for the Prevention of the Transmission of M. tuberculosis. This Plan will be the focus of annual personnel development training and new employee orientation for all affected employees.
Employees are urged to study all provisions of the Plan very carefully. All questions or comments should be directed to the Office of Environmental Health and Safety (348-5905). The Plan will be subject to review and revision, as needed. Annual review of the Plan will be scheduled for each November.
I. Key Definitions
HCW Health Care Worker - Any health-care facility employee who has contact with patients or must access patient care areas as part of his/her occupational responsibility.
PURIFIED PROTEIN DERIVATIVE tuberculin test A method used to evaluate the likelihood that a person is infected with M. tuberculosis.
PURIFIED PROTEIN DERIVATIVE tuberculin test conversion A change in PPD test results from negative to positive.
TB INFECTION A condition in which living tubercle bacilli are present in the body but the disease is not clinically active. Infected persons usually have positive tuberculin reactions, but they have no symptoms related to the infection and are not infectious
TUBERCULOSIS A clinically active, symptomatic disease caused by an organism in the M. tuberculosis complex.
II. Exposure Determination
Attach a copy of the Risk Appraisal Survey (Attachment A) which is completed annually by your Administrative Unit Supervisor.
III. Methods of Compliance
A. Administrative
1. PPD Tuberculin Skin Test
a. Each U of A health-care facility shall make available to all HCWs the PPD tuberculin skin test to determine exposure to M. tuberculosis. The Mantoux technique (intradermal injection of 0.1 mL of purified protein derivative or PPD containing 5 tuberculin units) should be used as a diagnostic aid to detect tuberculous infection or exposure. Although tuberculin skin tests are <100% sensitive and specific for detection of infection with M. tuberculosis, no better diagnostic method has been devised. Tuberculin skin tests should be interpreted according to current guidelines. A summary of these guidelines for interpretation of PPD skin tests is:
(1) An induration of greater than or equal to 5 mm is classified as positive in:
*Persons who have HIV infection.
*Persons who have had recent close contact with TB patient.
*Persons with healed TB
(2) An induration of greater than or equal to 10 mm is classified as positive in all persons who do not meet any of the criteria above, but who have other risk factors for TB, including High-Risk and High-Prevalence Groups.
b. This procedure shall be performed under the supervision of a licensed physician and at no cost to the employee.
c. HCWs who receive the PPD skin test will be informed about the test and sign a consent form (Attachment C).
d. Each health-care facility shall maintain all records related to PPD skin tests administered to its HCWs. Included shall be evaluation of PPD skin tests as recorded on the PPD Skin Test Evaluation form (Attachment D).
B. Engineering controls
For those areas of a health-care facility which involve "High" risk of TB transmission, engineering controls such as negative pressure, source ventilation, room ventilation, etc. (see p. 8, section B). List below the location, installation date and maintenance due date of any specialized ventilation of germicidal applications employed in engineering controls:
|
Control |
Location |
Installation Date |
Maintenance Due Date |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
C. Personal Protective Equipment
Where there is potential for occupational exposure, employees will be provided and required to use personal protective equipment including, but not limited to, respirators. This equipment will be provided at no cost to employees.
Supplies may be obtained at the following locations:_____________________________
________________________________________________________________________
If reusable respirators are used, guidelines for selecting, cleaning, maintaining, storing, etc. are detailed in the U of A Respiratory Protection Program. Prior to leaving the work area, PPE must be removed and properly disposed of or placed in a designated area.
Listed below are types of PPE available for employees' use and circumstances under which each kind must be used.
Facility ___________________ Dept. ___________________ Date ________________
|
PPE ITEM |
PROCEDURE |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
If decontamination of PPE is required, it will be accomplished in the following manner:
|
EQUIPMENT |
DECONTAMINATION METHOD |
FREQUENCY |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
D. Required Work Practices
1. Put a surgical mask on all patients diagnosed with active TB.
2. HCWs shall wash their hands immediately or as soon as possible after removal of gloves or other PPE and after hand contact with any potentially infectious materials.
3. All PPE must be removed immediately upon leaving the work area and placed in an appropriately designated area.
4. Eating, drinking, smoking, applying cosmetics or lip balm and handling contact lenses are prohibited in work areas where there is a potential for occupational exposure.
5. Food and drink shall not be stored or consumed in any area where potentially infectious materials are present or where the environment may be contaminated with infectious agents.
6. The following hygienic work practices will also apply:
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
E. Communication of Hazards
Any area of a U of A health-care facility which is subject to exposure to TB from the performance High Risk Procedures or for isolation/treatment of patients diagnosed with or suspected to have TB, should be clearly designated as Restricted, Isolation or Treatment Rooms. These areas include:
Facility_________________________ Dept.___________________ Date_____________
|
ROOM |
PROCEDURE JUSTIFYING DESIGNATION |
|
|
|
|
|
|
|
|
|
|
|
|
F. Method of Record-keeping
1. Medical records following an exposure incident will be kept for the length of the worker's employment, plus 30 years. Records will be maintained in the health-care facility where the HCW is employed.
2. Training records shall be kept for 3 years. These records will be maintained in the employee's personnel files.
G. Coordination with the Public Health Department
As soon as a patient or HCW is known or suspected to have active TB, the patient or HCW should be reported to the public health department so that appropriate follow-up can be arranged and a community contact investigation can be performed.
H. Waste Disposal
All infectious waste destined for disposal shall be handled as required by the U of A Bloodborne Pathogen Policy.
I. Laundry
Laundry which has been contaminated with potentially infectious agents should be handled as required by the U of A Bloodborne Pathogen Policy.
J. Exposure Evaluation and Follow-up
Should an employee be exposed to potentially infectious material, post-exposure evaluations will be provided as described herein. Exposure is defined as "potential exposure to the exhaled air of an individual with suspected or confirmed TB disease", without the protection of a respirator.
* Following a report of an exposure incident, the employee will be provided a confidential medical evaluation and follow-up including:
1. Skin testing to detect TB infection using the Mantoux PPD test.(see Figure 2)
2. If a HCW is exposed to TB, he/she must report the exposure to the dept./area supervisor and then be referred for medical evaluation
3. Evaluation shall include details of the exposure, a baseline PPD skin test and a follow-up PPD skin test 12 weeks later.
4. Evaluation and any further treatment shall be provided at no cost to HCW.
5. Any HCW with persistent cough, especially in the presence of other symptoms or signs compatible with TB, will be evaluated promptly for TB.
6. All HCWs with newly recognized positive PPD tests or PPD test conversions will be promptly evaluated for clinically active TB. Those HCWs determined to be without active TB should be evaluated for preventive therapy. HCWs with TB infection, but not active TB, may be allowed to continue their work routines.
7. If HCWs have active TB of the lungs or airway, they are to be restricted from working until they are no longer infectious. Criteria for return to work include three consecutive daily sputum smears that test negative for TB, the absence of coughing and a faithful adherence to the anti-TB medication therapy.
* The attending physician will be provided the following information:
1. A description of the affected employee's duties as they relate to the employee's occupational exposure.
2. Results of the individual's PPD skin tests.
3. All employee medical records relevant to the treatment of the employee.
* The attending physician will provide a written opinion to this employer concerning the following:
1. The physician's recommended limitations upon the employee's ability to receive a PPD skin test.
2. A statement that the employee has been informed of the results of the medical evaluation and that the employee has been told about any medical conditions resulting from exposure to M. tuberculosis or other potentially infectious agents.
3. All other findings and diagnoses shall remain confidential and shall not be included in the written report.
* Any employee who undergoes evaluation will be given a copy of the attending physician's written opinion within 15 days of the completion of the evaluation.
K. Information and Training
1. All HCWs with occupational exposure are required to participate in Exposure Control training prior to their initial assignment and at least annually thereafter. This training will be free of charge to employees and will be scheduled during working hours.
2. Refusal or failure to attend a required training session will result in the following disciplinary actions:
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
3. Each health-care facility is responsible for providing training for its employees.
4. HCWs will receive training and information in the following areas:
(a) Concepts of TB transmission, pathogenesis and diagnosis.
(b) The difference between TB infection and active TB disease.
(c) Symptoms of TB.
(d) The possibility of re-infection in persons with a positive PPD test.
(e) The potential for exposure to TB in the facility.
(f) Situations with increased risk of exposure to TB.
(g) A hierarchy of TB control measures.
(h) The facility's written TB infection-control plan.
(i) The purpose of PPD skin testing for TB and the significance of PPD test results.
ATTACHMENT C
PPD SKIN TEST CONSENT FORM
INFORMATION ON PPD SKIN TEST
The Disease. The etiological agent responsible for tuberculosis (TB) is Mycobacterium tuberculosis. In recent years, TB has become a rapidly spreading disease that has brought about new federal regulations, strict public health codes and concern among health-care workers and risk managers. Once thought to be nearly eradicated, TB and new strains of drug-resistant Mycobacterium tuberculosis have emerged in at least 40 states.
Tubercle bacilli are transmitted in airborne droplets that are generated when people with active TB disease of the lungs or air passages cough, sneeze, speak, spit, or sing. These very small droplets (1-5 u) remain airborne for extended periods of time in normal air currents, easily spreading throughout the environment. Whenever the airborne droplets of TB bacteria are inhaled deep into the lungs of a person, the result is infection of the alveoli. From these tiny air sacs, the TB infection can spread to various organs and tissues.
The probability of becoming infected with TB depends on the concentration of TB infected airborne particles, the duration of exposure and the immune state of those persons exposed. In people with a normal immune system, the body's natural defenses control the infection within 2-10 weeks. However, for people who are immuno-compromised, the threat of TB transmission is increased. Transmission of Mycobacterium tuberculosis infection to persons with HIV infection, young children and the elderly is of particular concern because their risk of developing active TB if infected is considerably higher than the general population. Thus, health-care facilities should be particularly alert to the need for preventing TB transmission wherever persons with these risk factors receive care or work.
PPD Skin Test
Tuberculin skin test. The Mantoux technique (intradermal injection of 0.1 mL of purified protein derivative or PPD containing 5 tuberculin units) should be used as a diagnostic aid to detect tuberculous infection. Although tuberculin skin tests are <100% sensitive and specific for detection of infection with M. tuberculosis, no better diagnostic method has been devised. Tuberculin skin tests should be interpreted according to current guidelines. See Figure 2 for the protocol for PPD skin test conversions. For persons with HIV infection, a reaction of >5 mm is considered positive. An induration of greater than or equal to 5mm is also considered as positive in persons who have had recent close contact with person who have active TB or in persons who have fibrotic chest radiographs (consistent with healed TB). A negative skin test does not rule out TB disease or infection. Because of the possibility of a false-negative result, the tuberculin skin test should never be used to exclude the possibility of active TB. Persons with HIV infection are more likely to have false-negative skin tests.
Contraindications
All HCWs shall be required to take a PPD skin test at least annually unless exclusion is recommended by a physician. The physician's written statement of exclusion must be retained with the HCWs medical records.
CONSENT
I have read the information provided by the Office of Environmental Health and Safety about Tuberculosis (TB) and PPD skin testing. I have had an opportunity to ask questions, understand the purpose of PPD skin testing and do consent to partake of a PPD skin test.
Signature of recipient ________________________________
Date_____________________________
Signature of Witness
________________________________________Date____________________________________
Figure 1. Risk Assessment
Analyze purified protein derivative (PPD) test conversion data, number of TB cases, and other risk factors by area and occupational group
If PPD test conversion rate is significantly greater than areas without TB patients or than previous rate in same area
or
if there is Cluster1 of PPD test conversions
or
Evidence of patient-to-patient transmission
|
If No, with : <6 TB patients/yr. in area LOW RISK |
If NO, with: >6 TB patients per/yr. in area INTERMEDIATE RISK2 |
If YES, HIGH RISK |
|
*Repeat PPD tests yearly *Repeat risk assessment yearly *Evaluate ventilation system annually and isolation room |
*Repeat PPD test every 6 months *Repeat risk assessment every 6 months *Evaluate ventilation system every 6 months and isolation room negative pressure daily while in use. |
*Initiate problem evaluation *Repeat PPD test every 3 months *Evaluate ventilation system every 3 months and isolation room negative pressure daily while in use. *Consider supplemental engineering measures. *Maintain highest index of suspicion of potential TB patients. |
1 Cluster - Two or more PPD conversions in one area or a single occupational group that works in multiple areas over a 3 month period.
2 Occurrence of drug-resistant TB in the facility or the community, or high prevalence of HIV infection among patients or workers in the facility may warrant a higher risk rating.
Figure 2. Protocol for investigating PPD-tuberculin skin-test conversions in HCWs
PPD test conversion in HCW
1. Evaluate HCW for active TB 2. Determine need for preventive or curative therapy. 3. Obtain history of possible TB exposure 4. Notify public health dept |
Probable exposure to M. tuberculosis outside of facility?
|
If NO Recognized exposure to M. tuberculosis in the facility? |
If YES No further investigation is necessary in the facility. |
If YES, 1. Identify and evaluate contacts of the suspected source patient. 2. Evaluate possible reasons for exposure and transmission 3. Implement interventions 4. Repeat PPDs and evaluation after 3 mos. |
If NO, 1. Review lab and infection control records to identify patients who have TB. 2.Match patients who have TB and HCW PPD Conversion, by time and location. 3. Probable source patient(s) identified? |
If NO, 1. Review PPD screening results of other HCWs in same area. 2. Consider additional PPD testing. |
|
|
|
Other PPD conversions detected? |
|
|
|
|
|
|
IF YES, Noscomial transmission more likely: Patient detection process, TB infection control |
IF NO, Noscomial transmission less likely: terminate investigation |
|
|
Potential problem identified? |
|
|
|
|
|
|
PPD conversions or other evidence of transmission? |
IF YES, 1. Implement intervention to correct problem 2. Repeat PPDs and evaluation after 3 mos. |
IF NO, |
|
|
|
|
NO |
IF YES, 1. Reassess possible reasons for exposure and transmission. 2 .Reassess interventions 3. Repeat PPDs and evaluation after 3 mos. |
|
|
|
|
|
|
|
PPD conversions or other evidence of transmission? |
|
|
|
|
|
If NO, Terminate investigation |
|
IF YES, 1. Implement high-risk protocol for area 2. Obtain consultation |
|
|
|
|