TUBERCULOSIS
It is estimated that 10 to 15 million persons in United States are infected with Mycobacterium tuberculosis, the organism that causes TB. The increase in multiple drug-resistant TB has caused further concern. Approximately 5% of all AIDS patients also have TB. Treating patients with active infectious TB poses a potential occupational hazard to health care workers (HCWs).The key to controlling the spread of TB in the work place is easy detection of patients with active TB, following an infection/exposure control plan and taking the proper precautions when working with patients suspected of or diagnosed with active disease. Eliminating the risk may not be possible. Adherence to the CDC guidelines will reduce the risk.
Are there any regulations regarding TB?
Yes, State laws require proper infectious control practices and reporting practices. The CDC released “Guidelines for Preventing the Transmission of Mycobacterium TB” in 1994. This document makes recommendations for reducing the risk of TB to health care workers. A copy of relevant parts of this document can be found in the appendix that follows. OSHA released draft regulations for TB in 1993, 1994 and again in 1997 . On December 31, 2003, OSHA withdrew the TB standard since OSHA felt that the risk factor had decreased in the previous 10 years due to compliance with the CDC guideline. NIOSH has developed and released recommendations on types and use of respirators. OSHA can inspects for TB infection control problems under the general duty clause of the “Occupational Safety and Health Act of 1970”. The information in this chapter follows the CDC Guidelines.
Mode of Transmission:
TB is a communicable disease caused by the bacterium “Mycobacterium tuberculosis”. It is spread from person to person through the inhalation of airborne particles containing M. tuberculosis (less than 5 microns in size). These particles are also called droplet nuclei. These droplets are produced when a person with active TB of the lung forcefully exhales, such as when coughing, sneezing, speaking or singing. These infectious particles can remain suspended in the air and can be inhaled by someone sharing the same air. Risk of transmission increases in closed areas where ventilation is poor and if air is shared for a prolonged period of time.
TB Infection and Disease:
TB infection (positive PPD) in a person who does not have active disease (symptoms) is not considered a case of active TB. A person with TB infection who does not have active disease cannot infect others. Active TB does not develop in everyone who is infected. ln the U.S., about 90% of infected persons remain infected for life and never develop symptoms of active TB. Most active cases occur in the lungs and are confirmed by chest radiograph and positive sputum culture. TB infection usually begins in the alveoli, where tubercle bacilli are initially able to multiply. Within 2-10 weeks after the initial infection with M. tuberculosis, the immune response limits further multiplication and spread of the tuberculosis bacilli. However, some of the bacilli remain dormant and viable for many years. The risk of developing active disease is greatest during the first 2years. Persons with TB in extra pulmonary sites are usually not considered infectious to other people.
Signs and Symptoms:
The signs and symptoms of TB vary according to the location of the disease. Generally the signs and symptoms of pulmonary TB will include a persistent cough (more than 3 weeks), chest pain, coughing up sputum and sometimes coughing up blood, fatigue, feeling ill, loss of appetite, weight loss, fever, and night sweats.
Treatment of TB:
TB is usually curable if it is diagnosed early and if effective treatment is instituted without delay. TB must be treated with multiple antibiotics and for a long time compared with most other infectious diseases. Usual treatment time is 6 - 9 months. If treatment does not continue the tubercle bacilli may survive to make the person infectious again and may foster the development of drug-resistant mycobacteria. * A table of anti-tuberculosis drugs can be found in the CDC guidelines in appendix.
Exposure Classification/Risk Factors:
Anyone who has close contact and has shared airspace with a person who has active infectious TB is at risk for TB. The CDC classifies facilities as “high risk”, “intermediate risk”, “low risk”, “very low risk” or “minimal risk”. ALL MEDICAL FACILITIES MUST PERFORM A RISK ASSESSMENT.
The infection control program will be based on this rating.
* Detailed information on how to perform this can be found in the CDC, October 28,1994 guideline found at the end of this chapter.
CDC Risk Assessment Classifications:
Minimal Risk: Entire facility does not admit TB patients and is not located in a community with TB (information can be obtained from public health department data). Very Low Risk: Entire facility does not admit TB patients to inpatient areas BUT may receive initial assessment and perform diagnostic evaluations. Patients with confirmed TB will be referred to an appropriate facility. Facility is in an area with reported TB cases. No cases have been seen in facility in prior year. Depending on amount of patients seen per/year the risk classification will be upped to low, intermediate or high. Low Risk: One to 6 active infectious TB patients are treated per year. The PPD (Mantoux test) conversion rate is the same as the conversion rate of HCWs without occupational exposure. If <1 or >6 TB patients are seen the classification will be changed accordingly.
Intermediate Risk: Exposure to 6 or more active infectious TB patients per year. The PPD (Mantoux test) conversion rate among HCWs is the same as the conversion rate in HCWs without occupational exposure. High Risk: Frequent shared air space with known active infectious TB patients. The PPD (Mantoux test) conversion rate among HCWs greater than the conversion rate among HCWs without frequent exposure. Note: Larger facilities may classify, different area’s of the facility at different risk. The CDC risk rating (of facility or section of facility) will be reviewed and assessed annually. The risk rating will be adjusted up or down according to the results of this assessment. The exposure control plan will be revised accordingly. The initial risk assessment was performed on ___________________________.
Annual Risk Assessment (perform based on previous calendar year)
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Environmental factors that enhance the likelihood of transmission include:
1. Exposure of susceptible persons to an infectious person in relatively small enclosed spaces.
2. Exposure to a person with un-diagnosed and un-treated infectious TB.
3. Inadequate local or general ventilation when working with patients with active infectious TB.
4. Re-circulation of air containing infectious droplet nuclei.
The magnitude of the risk varies considerably by type of health-care-facility, patient population served, prevalence of TB in the community, procedures being performed on patients and job assignment of the health care worker. It is the employers responsibility to determine which employees will be covered by this guideline
Mantoux (PPD) Screening:
The Mantoux tuberculin skin test is the recommended method of skin testing to determine whether a person is infected with M. tuberculosis. A positive reaction to the tuberculin test usually means the person has been infected with M. tuberculosis. Persons who have a positive skin test and present with TB symptoms will be evaluated with a chest radiograph to rule out pulmonary TB.
For the initial TB skin test, a two-step testing procedure is recommended. Two-step testing reduces the likelihood that a boosted skin reaction will be interpreted as representing recent infection. If the reaction to the first skin test is negative, a second test will be given 1 -3 weeks later. If the reaction to this second test is positive, it probably represents a boosted reaction. Based on the second test result, the person will be classified as being TB infected (positive) or negative and managed accordingly. HCWs that can document a negative PPD test within the past year need only a one step test. HCWs who can document previous history of a positive TB test or is known to have completed adequate treatment or preventative therapy will be exempt from further PPD screening unless they show symptoms suggestive of TB. Repeated testing of uninfected persons does not sensitize them to tuberculosis.
HCWs who have negative skin test results will be retested periodically (frequency depends on risk factor classification, see CDC, 10128194 guidelines) to screen for new infection and disease. Hepatitis B vaccination is no a contraindication for Mantoux testing. TB skin testing may be done before or at the same time as immunization with viral vaccines against measles, rubella or mumps or 8 - 12 weeks after such administration.
The OSHA, CDC and State guidelines for TB infection control do not exempt employees who have a history of Bacillus of Calmette and Guerin (BCG) vaccination unless the vaccination was received within the past 5 years. It should be noted that BCG does not affect the risk of infection, it decreases the risk for progression from latent TB to active TB. A blood test, QuantiFERON-TB was approved by the Food and Drug Administration in 2006 and may be done in place of a Mantoux test on employees who have received BCG. This test is not affected by BCG. Mantoux testing will be done by an appropriate health care professional (how to perform, interpret and follow-up the Mantoux test is found in the CDC guidelines in appendix) at no charge to the employee. Testing will be done at a convenient time during the workday. Test result must be documented in the employees file. All employees will receive a copy of their test results.
Employees with positive reaction will be evaluated and monitored accordingly.
CDC Guidelines for Follow Up Mantoux Testing:
Minimal Risk Facilities : N/A or variable
Very Low Risk Facilities : variable (upon exposure)
Low Risk Facilities : annual
Intermediate Risk Facilities : 6 - 12 months
High Risk Facilities : 3 - 6 months
* A list of questions and answers on Mantoux testing is found at the end of this chapter
TB EXPOSURE & INFECTION CONTROL PLAN
POLICY: The key to preventing transmission is to be aware of TB and follow precautions! In general, the symptoms of active TB are symptoms that patients will likely seek medical treatment for at a medical office or clinic. The population served by some facilities may be a low to relatively high. This is determined when the risk evaluation is performed. One person will be assigned to implement facility plan. All employees will follow this plan.The person in charge of implementing the TB infection control plan in the facility of ________________________________ is ___________________________
If this person changes write the new name and date changed here:
Name : _________________________________ Date : _______________
Name : _________________________________ Date : _______________
Name : _________________________________ Date : _______________
Name : _________________________________ Date : _______________
Name : _________________________________ Date : _______________
Name : _________________________________ Date : _______________
Name : _________________________________ Date : _______________
Early Identification of Patients with Potential TB:
All patients will be questioned during initial medical history about a history of TB disease and symptoms suggestive of TB. Any patient presenting with the following symptoms will be evaluated for disease. Evaluation of disease will include: medical history, physical examination, PPD skin test, chest radiograph and possible sputum culture or other appropriate specimen testing.
Patient with a persistent cough for more than three weeks will be evaluated for TB work-up.
Patient with pulmonary, respiratory, systemic signs or TB related symptoms will be evaluated for disease.
Patient known or suspected of having HIV with cough or fever will be evaluated.
Patient with pulmonary or systemic signs that were initially attributed to other etiologies, but which do not respond to appropriate therapy will be evaluated for TB.
Infants and children living in households with an active case of pulmonary tuberculosis, regardless of symptoms will be evaluated for disease.
Once the patient is identified, precautions listed the section “Infection Control for Medical Offices” (or appropriate health care facility) will be implemented.
TB Policy for Patient Evaluation and Referral:
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Employee Education:
Employee education regarding TB and TB infection control will be done upon initial employment and at least annually thereafter. Training will include:
1. Purpose, interpretation and value of skin testing
2. Procedures to prevent TB transmission (infection control plan)
3. Importance of compliance
4. Cause and transmission of TB
5. Distinction between TB disease and TB infection
6. Signs and symptoms of TB
7. Risk factors in health care facility
8. Treatment
9. Prognosis
10. Facility information on screening program
11. Purpose, proper selection, fit and use of PPE (respirators)
12. Engineering controls
Infection Control Policy for Medical Offices and Clinics:
The following infection control policies will be implemented once a patient suspected of having TB is identified in the physician office or clinic:
1. Any patients with symptoms will be evaluated and diagnosed so that HCWs can identify infectious patients.
2. Once a patient is identified with active pulmonary TB an effort will be made to separate this patient from other patients while in the waiting room. If this is difficult to do, have the patient wear a surgical mask while waiting.
3. The patient will be put into an examining room soon as possible.
4. HCW’s entering and assisting in the examination will be kept to a minimum. They will be provided with NIOSH approved respirator masks (see note below) to wear while working with the patient.
5. Patients with suspected active pulmonary TB will be instructed to cover the nose and mouth when coughing, sneezing, etc. They will be asked to wear a surgical mask during the examination. This will not totally prevent exposure but will decrease the creation of infectious aerosol droplets expelled by the patient.
6. Room will be well ventilated before the next patient is put in room.
7. Procedure for sputum collection will not be conducted at the facility unless a specially equipped room is available. The patient will be sent to a hospital that has a special collection room for this or done at their home. Procedures for suctioning, cough-inducing procedure or aerosol generating procedures will not be performed at the facility – unless facility has a negative pressure room or TB approved air filtration system.
8. Cough-inducing procedures and laboratory testing of sputum will not be performed by the facility or in the facility.
Infection Control Policy for In-Office Operating Rooms:
Elective operative procedures on patients with TB will be delayed until the patient is no longer infectious. If procedure must be done, it will be done in an operating room with anterooms and/or room will have a HEPA air filtration system. Doors will be closed and traffic in and out kept to a minimum.
Infection Control Policy for Dental Offices:
During initial medical history the HCW will routinely ask all patients about a history of TB disease and symptoms suggestive of TB.
Patients with history and symptoms suggestive a active TB will be sent for evaluation for possible infectiousness.
Elective dental treatment will be delayed until a physician confirms that the patient does not have infection.
If urgent dental care must be provided the dental HCW will use respiratory protection while performing procedures on such patients.
Dental HCWs who work in a facility where there is a likelihood of exposure to patients with infectious TB will participate in an employer sponsored PPD testing program and have respirators available.
Infection Control Policy for Home Health Care:
HCW’s entering homes of patients with suspected or active TB will wear respiratory protection. The patient will be instructed to cover their mouth with a tissue or wear a surgical mask if coughing or sneezing. Precautions may be discontinued when the patient is no longer infectious.
NOTE: AIl HCW’s having contact with patients diagnosed with or suspected of having active infectious TB will wear a NIOSH approved properly fitted high efficiency respirator.
See the section that follows on respiratory protection.
Infection Control Policy - Facility Cleaning:
Since tuberculosis is transmitted though the air rather than by fomites or direct contact, the disposal of personal items, gowns, table paper etc. would be handled the same as other patients. No special cleaning over and above the normal disinfecting (hospital grade - level 2 or 3) and cleaning of examining rooms is necessary. Waste from patients with TB is not considered regulated medical waste in most states (check !) - UNLESS it is blood and/or body fluid soaked. All laboratory specimens ARE considered medical waste. Dental offices, in-office examining and operating rooms would follow the same guidelines as would be followed for the bloodborne pathogen standard.
Engineering Controls:
Air Filtration Systems: If office/clinic has a high population of infectious TB patients or performs high risk procedures, an examining room with an approved ventilation system (e.g. negative pressure) or outside exhaust or FIEPA filter will be installed. Air will not be re-circulated into the office from this treatment room. A routine maintenance program on this system will be documented every 6 months. See OSHA and CDC guidelines for more information.
Respiratory Protection:
All HCWs with potential exposure will be fitted and trained in the use of respiratory protection. The CDC recommends respirators be available in all low to high risk facilities. Common surgical masks are not effective in preventing Mycobacterium tuberculosis exposure to the HCW because they do not trap small enough particles and they allow leakage around the mask.
The precise level of effectiveness of respiratory protection recommended for protecting HCWs from transmission of M. tuberculosis in health-care setting has been studied by the NIOSH, the CDC and OSHA. Based on the most current data (NIOSH 42 CFR 84 - June 8, 1995) respirators are classified under filter efficiency classes such as “95,” “99,” and “99.97 .” In addition there are three divisions within each class that designate what the filter is approved for. These divisions are “N,” “R,” or “P.”
The “N” rating stands for Not for oil aerosols, the “R” rating stands for Resistant to oil aerosols and the “P” rating stands for oil aerosol Proof. ALL the new classes are approved by NIOSH for TB protection. HEPA filter masks offer the greatest protection and are recommended as the respirator of choice for most health care settings.
Recommended respirators are available from Laboratory Safety Supply
- 1-800-356-0783 or many of the medical suppliers.
Once respirators are purchased, the OSHA General lndustry Respiratory Protection Standard to M tuberculosis requires that the respirators be fit tested (face-seal leakage test). Fittings must be performed annually or as needed by a properly trained individual*. Training, respirator care and maintenance and medical monitoring must be followed and documented. A self test (positive and negative pressure test) will be performed each time a respirator is donned - if applicable to type of respirator.
Notes A Summary of Features of Respiratory Protective Devices can be found in the CDC guidelines in the appendix.
* All hospitals perform fit testing. Fit test kits may be purchased from respirator manufacturers. Videos can be purchased to teach how to perform the fit test.
Information on Respirators* (if applicable - required for risk classifications low to high):
This facility uses the following brand mask: __________________________________
Masks are purchased from: _______________________________________________
Model brand and number: ____________________ _________________________ Initial fit testing was performed on: _______________________________ Follow up fittings on :
_________ _________ _________ _________ _________ _________
_________ _________ _________ _________ _________ _________
Masks are kept: ______________________________________________________
Masks are cleaned with: __________________________________ before storing
Masks are disposable (Y/ N): _____________
Training on use and care of respirators has been supplied (date):__________________
* Masks must be NIOSH approved for TB
Screening, Prevention and Treatment of TB for HCWs:
The medical facility that provides care for patients with or at risk for TB will maintain active surveillance for TB among HCWs. HCWs (full and part time who may have direct exposure) will be given a Mantoux tuberculin skin test upon employment. Base line skin testing is optional but recommended for employees at minimal risk facility and are required for all other CDC risk classifications. Employees who have a documented history of a positive PPD, adequate treatment or preventive therapy may be exempt from further PPD screening unless they develop signs or symptoms suggestive of TB. Employees who test positive (with no previous history) will be promptly evaluated for active TB. The evaluation will include a clinical examination and a chest radiograph. If the chest radiograph is negative - routine follow-up chest radiographs are not required for asymptomatic HCWs. An employee health questionnaire will be used to annually screen for symptoms of disease. HCWs who have a positive PPD and do not have active TB will be evaluated for possible preventive therapy. Any HCW with a persistent cough for more than 3 weeks in duration, especially in the presence of other symptoms, will be evaluated promptly for TB’ If the employees risk assignment changes they will undergo a repeat PPD test. The facilities policy on procedures for infection control of TB transmission will be available to all employees.
* Forms to document Mantoux testing and exposure incidents are found in this chapter.
Record Keeping:
Record keeping for PPD tests will include, date of testing, testing material and batch number used, date test was read, the size of the reaction in millimeters, interpretation, name of the person administering and/or interpreting the results. If there has been an on the job exposure, an incident report will be filled out. A written opinions of medical evaluation following an exposure must be received and documented within 15 days. If a positive skin test (TB infection) turns into active disease, the disease will be reported State Department of Health Tuberculosis Control Program upon diagnosis. Exposure records must be kept for the length of employment plus 30 years.
Write the address and phone number of your State Department of Health here:
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
Phone: __________________________________________________
Exposure Follow Up:
HCWs who have been exposed to active infectious TB will be evaluated promptly for TB. A Mantoux tuberculin skin test will be given as soon as possible after exposure. If the initial skin test result is negative, the test will be repeated 12 weeks after the exposure. Exposed persons who have skin test reactions of 5 millimeters or greater or who have symptoms suggestive of TB will be evaluated with chest radiograph. The recommendation for preventive therapy will be made by the physician providing the follow-up.
Contact Investigations:
Close contacts of HIGHLY active infectious patients will be considered for preventive therapy even if their initial TB skin test is negative. A second skin test will be given 12 weeks after contact with the infectious person has ended. If the result is also negative, preventative therapy may be stopped.
Problem Evaluation:
If a skin conversion occurs the HCW will be promptly evaluated for TB and placed on preventative or curative therapy. Other HCWs working in the same area as infected worker will be re-evaluated. Office/clinic must initiate a problem evaluation for things such as patient detection and engineering controls. If no specific problem can be documented, follow protocols for a higher risk classification until there are two consecutive three-month periods with no evidence of transmission.
Work restrictions for Employees with suspected or diagnosed TB:
Any employee with active or suspected pulmonary or laryngeal TB must be excluded from work until the following conditions are met:
1. adequate treatment is instituted
2. cough is resolved
3. tests reports show decreased numbers of organisms
4. three consecutive sputum cultures are negative
5. physician certifies the employee is no longer infectious
6. tuberculosis is ruled out
Documentation of the above conditions will be provided to the employer before the employee returns to work.
Employees who discontinue treatment before recommended course is completed will not be allowed back to work.
All employees removed from the work place because of TB will receive pay and benefits in accordance with worker’s compensation, disability and other applicable laws.
Health care personnel who are receiving preventative treatment for exposure may continue to perform their usual work activities.
Education of Employees:
Employees with job duties that require them to work with patients who have or may have TB will be given a general safety training program on TB. The program will include:
Transmission of TB
Potential for occupational exposure
Infection control policies
Purpose of PPD skin test
Post exposure evaluation
Treatment of the disease
Contents of the infection control plan
GLOSSARY
Alveoli The small air sacs in the lungs which lie at the end of the bronchial tree. The site where carbon dioxide is replaced by oxygen in the lungs, and the site where TB infection usually begins.
BCG Bacillus of Calmette and Guerin - a TB vaccine widely used in some parts of the world.
CDC Center for Disease Control, Atlanta, Georgia.
Chest Radiograph A radiograph (type of X-ray) of the chest is taken to view the respiratory system of persons showing signs or symptoms of TB.
Fomites Linens, books, dishes, or other objects used or touched by a patient. They are not involved in transmission of TB.
HCW Health Care Worker - all paid and unpaid persons working in a health-care setting who have the potential for exposure to M. tuberculosis.
HEPA High-Efficiency particulate Air Filter - specialized filter that is capable of removing 99.97% of particles 0.3 microns in diameter. Requires expertise in installation and maintenance.
Infectious Capable of causing disease. In TB, a person is infectious only if he/she has clinically active disease.
Mantoux Test A tuberculin test given by injecting a measured amount of liquid tuberculin into the dermis (second layer of skin) with a needle and syringe.
NIOSH National lnstitute for Occupational Safety and Health. Presently developing procedures to rate respiratory equipment.
PPD Purified Protein Derivative - a type of purified tuberculin preparation derived from old tuberculin and developed in the 1930’s. The standard Mantoux test uses 5 TU (tuberculin units) of PPD.
Sputum Material coughed up from deep within the lungs. It should not be confused with saliva or with nasal secretions.
REFERENCES
Core Curriculum on Tuberculosis. U.S. Department of Health and Human Services, CDC, April 1991.Guidelines for Preventing the Transmission of Mycobacterium tuberculosis in Health Care Facilities, 1994. CDC, U.S. Dept. of health and Human Services, Oct.28,1994.
Preventing the Transmission of Tuberculosis in Health-Care Facilities (draft guidelines). Federal Register, Department of Health and Human Services, Tuesday October 12, 1993.
Siegel, Bruce M.D., Epidemiology, Diagnosis, Treatment and Prevention of Tuberculosis, N.J. Department of Health, Division of Epidemiology, Environmental and Occupational Health Services, undated.
Siegel, Bruce M.D., Guidelines for the Prevention of Tuberculosis Transmission in Health Care Facilities. N.J. Department of Health, Division of Epidemiology, Environmental and Occupational Health Services, not dated.
TB The Connection HIV. U.S. Dept. of Health and Human Services, CDC, Sept 1993 Occupational Exposure to Tuberculosis; Proposed Rule. Federal Register, 29 CRF Part 1910, Oct.17, 1998.
Brown, James, PhD. TB: Keeping an Ancient Killer at Bay, MLO, November 2004.
COMMON QUESTIONS ON MANTOUX TESTING
Q. Can we use a Tine test in place of the Mantoux test?A. No - OSHA, CDC and State guidelines ALL require the use of the Mantoux test (also called PPD).
Q. Can employees sign a declination form similar to the one that was used for Hepatitis under the Bloodborne Pathogen Standard, if they do not want to be tested?
A. The CDC guidelines do not give the employee this option - however, this document is a guideline. Since the OSHA regulation was withdrawn in 2003 - it may be up to the employer to offer such an option. An exception to the testing would be a person who can document the potential of a severe reaction due to a previous BCG injection in the past or a person with a history of positive PPD test with adequate treatment for disease or preventive therapy for infections.
Q. Do we need to do a2 step Mantoux?
A. OSHA, CDC and State guidelines all recommend an initial 2 step Mantoux on employees. All employees, including those with a history of BCG vaccination, are to receive a Mantoux test. Exception: Employees with a documented history of positive PPD test, adequate treatment for disease, or adequate preventive therapy, will be exempt from further PPD screening unless they develop signs or symptoms suggestive of TB . Employees who have documentation of a negative Mantoux test being performed within the past year need only have one (second test) Mantoux test done.
Q. What is the reason for the two-step Mantoux (PPD) test?
A. The purpose of a two-step test is to detect boosting phenomena that might be misinterpreted as skin test conversions in the future. This means that the first test can re-stimulate or enhance remotely established and subsequently weakened hypersensitivity reaction. The second tests rules out this booster phenomenon. A positive second test indicates boosting of a subclinical hypersensitivity state due to old infection rather than recent conversion requiring a work up and subsequent treatment or prophylaxis therapy. If the two step approach is not taken, a positive second test done after employment will result in the question of whether the employee needs a work up for a skin test conversion or is simply manifesting the booster phenomenon. The ability of person who has had a TB infection to react to PPD may gradually wane. For example, if tested with PPD, adults who were infected during their childhood may have a negative reaction, However, the PPD could boost the hypersensitivity, and the size of the reaction could be larger on a subsequent test. This boosted reaction may be misinterpreted as PPD test conversion from a newly acquired infection.
A history of past positive skin test is important. BCG-induced tuberculin skin test reactivity wanes over time. People who have received BCG will be considered infected with M. tuberculosis if they have a positive reaction to 5 TU of PPD tuberculin. They will be evaluated for TB disease and managed accordingly.
Q. How often do we have to perform follow-up Mantoux tests?
A. Follow-up testing is based upon the risk rating of your facility. Refer to your TB exposure control plan or the chart from the CDC found in the TB chapter.
Q. Do I have to record a positive Mantoux on the OSHA 300 form?
A. No. As of January 1, 2001,physician and dental offices no longer need to keep OSHA 200 or 300 forms.
Q. Which employees should be included in the Mantoux Test screening?
A. This answer is not as clear cut as we would like it to be in any of the guidelines. According to CDC guidelines “Health care workers who work in medical offices where there is a likelihood of an exposure to patients who have infectious TB should be included in the employer-sponsored education, training, and PPD testing programs at the appropriate risk level of the facility.”
Q. What about Mantoux Testing for Employees that have had BCG Vaccines or tested positive in the past.
A. The OSHA, CDC and State guidelines for Tuberculosis infection control do not exempt employees who have had BCG vaccines in the past or employees who tested positive years ago from the requirement of baseline testing. An exception to this would be employees who received the BCG vaccine within the last five years. These employees should not be given the baseline Mantoux for any reason. They should be counseled on the symptoms of the disease and have a documented negative chest X-ray. Employees that state they had received BCG (longer than 5 years ago) or employees who have had positive tests in the past must provide documentation of previous positive test results. If this documentation cannot be provided, the facility may choose to test using a2006 blood test approved by the FDA called QuantiFERON-TB. This blood test is not affected by BCG. The pharmaceutical company’s package insert with the directions for administration of a Mantoux makes it clear that there are contradictions to administration and/or modifications that should be made for people who have had positive reactions in the past and people who have been given BCG
Q. Do I need to send an employee with a positive Mantoux test for an x-ray?
A: The CDC says it is important to obtain an initial chest x-ray on personnel with positive PPD test reactions, documented PPD test conversions or pulmonary symptoms suggestive of TB. There is no need to follow-up with a chest x-ray unless the employee develops pulmonary symptoms suggestive of TB.
Answers are taken from the Federal Register, CDC Guideline for Infection Control, 9/8/97.
THINGS TO REMEMBER:
Any employee who has a positive skin reaction will get a chest X-ray. Any employee that can document a positive reaction and a negative chest X-ray in the last year does not need additional testing or follow-up. If the employee cannot document this, use the low dosage recommendations from the pharmaceutical company.
BCG immunization dwindles over time. An employee that had it as a child may no longer have a positive reaction.
Employees with initial baseline tests that are positive do not get the second dose of PPD that is performed to detect a boosting reaction. They get a chest X-ray.
Any employee who has had a single Mantoux test in the past year will only need another single test to comply with the guidelines two-step Mantoux test. The second PPD test result serves as the baseline documentation.