Slide Set— Guidelines for Preventing the
Transmission of M. tuberculosis in Health-Care Settings, 2005
Text Only Version
Download complete
Power Point Presentation (150 slides) – (1011 KB)
Return to Main Menu
Slide 1
Guidelines for Preventing the Transmission of
M. tuberculosis in Health-Care Settings, 2005
Division of Tuberculosis Elimination
December 2006 note: Slide #123 has been edited.
Image: collage of health care workers
Slide 2
Purpose of 2005 Guidelines
- Update and replace 1994 Mycobacterium tuberculosis
infection control (IC) guidelines
- Further reduce threat to health-care workers (HCWs)
- Expand guidelines to nontraditional settings
- Simplify procedures for assessing risk
- Promote vigilance and expertise needed to avert
another TB resurgence
Slide 3
What’s New (1)
- Change of risk classification and tuberculin skin test
(TST) frequency
- Expanded scope addressing lab, outpatient, and
nontraditional settings
- Expanded definitions of affected HCWs
- “TST” instead of “PPD”
Slide 4
What’s New (2)
- QuantiFERON-TB Gold test (QFT-G)
- QFT-G is a type of blood assay for M. tuberculosis
(BAMT)
- – Measures the patient’s immune system reaction to
M.
tuberculosis
- – Blood samples must be processed within 12 hours
- – Interpretation of QFT-G results is influenced by the
patient’s risk for infection with M. tuberculosis
- – An alternative to TST
Slide 5
What’s New (3)
- Term “airborne infection isolation” (AII)
- Criteria for initiating and discontinuing AII
precautions
- Respirator fit testing and training; voluntary use of
respirators by visitors
- Additional information on ultraviolet germicidal
irradiation (UVGI)
- Frequently asked questions (FAQs)
Slide 6
Change in Risk Classifications
| Previous |
New |
| Minimal |
Low |
| Very low |
Medium |
| Low |
Potential
ongoing transmission |
| Intermediate |
|
| High |
|
Slide 7
HCWs Who May Be Included in a TB Testing
Program
- Paid and unpaid persons working in health-care
settings who have potential for exposure to M. tuberculosis
through shared air space with infectious patient
- Includes part-time, full-time, temporary, and contract
staff
- All HCWs whose duties involve face-to-face contact
with suspected or confirmed TB should be in a TB screening program
Slide 8
Transmission of M. tuberculosis
- Spread by airborne route; droplet nuclei
- Transmission affected by
- – Infectiousness of patient
- – Environmental conditions
- – Duration of exposure
- Most exposed persons do not become infected
Slide 9
TB Pathogenesis (1)
Latent TB Infection
- Once inhaled, bacteria travel to lung alveoli and
establish infection
- 2–12 wks after infection, immune response limits
activity; infection is detectable
- Some bacteria survive and remain dormant but viable
for years (latent TB infection, or LTBI)
Slide 10
TB Pathogenesis (2)
Latent TB Infection
- Persons with LTBI are
- – Asymptomatic
- – Not infectious
- LTBI formerly diagnosed only with TST
- Now QFT-G can be used
Slide 11
TB Pathogenesis (3)
Active TB Disease
LTBI progresses to TB disease in
- Small number of persons soon after infection
- 5%–10% of persons with untreated LTBI sometime during lifetime
- About 10% of persons with HIV and untreated LTBI per year
Slide 12
Persons at Higher Risk for Exposure to and
Infection with M. tuberculosis (1)
- Close contacts
- Foreign-born persons from or areas with high TB
incidence
- Residents and staff of high-risk congregate settings
- Health-care workers who serve high-risk clients
Slide 13
Persons at Higher Risk for Exposure to and
Infection with M. tuberculosis (2)
- HCWs unknowingly exposed to TB patient
- Low-income, medically underserved groups
- Locally defined high-risk groups
- Young persons exposed to high-risk adults
Slide 14
Persons at High Risk for LTBI Progressing to TB
Disease
- Persons coinfected with HIV and M. tuberculosisis
(highest risk)
- Those with recent M. tuberculosis infection
(within 2 years)
- Children under 4 years of age
- Persons with certain clinical conditions or other
conditions of compromised immunity
- Those with a history of untreated or poorly treated TB
Slide 15
TB Patient Characteristics That Increase Risk
for Infectiousness (1)
- Coughing
- Undergoing cough-inducing or aerosol-generating
procedure
- Failing to cover cough
- Having cavitation on chest radiograph
Slide 16
TB Patient Characteristics That Increase Risk
for Infectiousness (2)
- Positive acid-fast bacilli (AFB) sputum smear result
- Disease of respiratory tract and larynx
- Disease of respiratory tract and lung
or pleura
- Inadequate TB treatment
Slide 17
Environmental Factors That Increase Risk for
Transmission
- Exposure in small, enclosed spaces
- Inadequate ventilation
- Recirculating air containing infectious droplets
- Inadequate cleaning and disinfection of equipment
- Improper specimen-handling procedures
Slide 18
Risk for Health-care–Associated Transmission of
M. tuberculosis (1)
Risk varies by
- TB prevalence in health-care setting
- TB prevalence in community
- Patient population served
- Health-care worker occupational group
- Effectiveness of infection control measures
Slide 19
Risk for Health-care–Associated Transmission of
M. tuberculosis (2)
Linked to close contact with infectious TB
patients during procedures generating aerosols
- Bronchoscopy
- Endotracheal intubation or suctioning
- Open abscess irrigation
- Autopsy
- Sputum induction
- Aerosol treatments
Slide 20
Previous Health-care–Associated Transmission of
M. tuberculosis (1)
In hospital TB outbreaks, 1980s–1990s
- MDR TB spread to patients and HCWs
- Many patients, some HIV-infected HCWs
- Rapid progression from new infection to disease
- Factors
- – Delayed diagnosis
- – Lapses in AII precautions
- – Lapses in respiratory protection
Slide 21
Previous Health-care–Associated Transmission of
M. tuberculosis (2)
Follow-up
- Transmission much decreased or ceased in a setting
when recommended infection control interventions implemented
- However, effectiveness of each intervention could not
be determined
Slide 22
Fundamentals of Infection Control (1)
Hierarchy of Infection Control
- Administrative Controls [two administrators working at a
table]
- Environmental Controls [female patient in bed]
- Respiratory Protection [female health care worker wearing an
N-95 respirator]
Slide 23
Fundamentals of Infection Control (2)
Hierarchy of Infection Control
- Administrative controls: reduce risk of
exposure via effective IC program
- Environmental controls: prevent spread and
reduce concentration of droplet nuclei
- Respiratory protection controls: further reduce
risk of exposure in special areas and circumstances
Slide 24
Administrative Controls (1)
Most Important
- Assign responsibility for TB infection control (IC)
- Work with health department to conduct TB risk
assessment and develop written TB IC plan, including AII precautions
- Ensure timely lab processing and reporting
- Implement effective work practices for managing TB
patients
Slide 25
Administrative Controls (2)
- Test and evaluate HCWs at risk for TB or for exposure
to M. tuberculosis
- Train HCWs about TB infection control
- Ensure proper cleaning of equipment
- Use appropriate signage advising cough etiquette and
respiratory hygiene
Slide 26
Environmental Controls
- Control source of infection
- Dilute and remove contaminated air
- Control airflow (clean air to less-clean air)
Slide 27
Respiratory Protection (RP) Controls
- Implement RP program
- Train HCWs in RP
- Train patients in respiratory hygiene
Slide 28
Relevance to Biologic Terrorism Preparedness
- Multidrug-resistant M. tuberculosis is
classified as a category C agent of biologic terrorism
- Implementing guidelines in this document is essential
to preventing the transmission of M. tuberculosis in
health-care settings
Slide 29
Recommendations for Preventing M.
tuberculosis Transmission in Health-Care Settings
[Image: four health care workers]
Slide 30
Develop an Infection Control (IC) Program
- Perform TB risk assessments in all settings
- Develop TB IC program as part of overall IC program
- Base IC program on risk assessment
- Determine details of IC program by likelihood that
persons with TB will be encountered in that setting or transferred
to another setting
Slide 31
Infection Control Program (1)
Settings Expecting to Encounter TB Patients
- Assign and train TB IC program manager
- Collaborate with local health department to develop
administrative controls, including
- – Risk assessment
- – Written TB IC plan, including protocols for
identifying, evaluating, managing infectious TB patients
- – Testing and evaluation of HCWs
- – Training and education of HCWs
- – Problem evaluation and contact investigation
- – Coordination of discharge
Slide 32
Infection Control Program (2)
Settings Expecting to Encounter TB Patients
- Develop plan for accepting TB patients or suspects
transferred from another setting
- Implement and maintain environmental controls,
including AII rooms
- Implement RP program
- Provide ongoing training and education of HCWs
Slide 33
Infection Control Program (3)
Settings Not Expecting to Encounter TB Patients
- Assign responsibility for TB IC program
- Collaborate with local health department to develop
administrative controls, including
- – Risk assessment
- – Written TB IC plan that outlines protocol for triage
and transfer of TB patients to another health-care setting
- – Problem evaluation and contact investigation
Slide 34
TB Risk Assessment (1)
Settings Expecting to Encounter TB Patients
- Collaborate with health department to review community
TB profile, obtain epidemiologic data for risk assessment
- Review number of TB patients encountered
- Determine
- – HCWs to be included in TB testing and in RP program
- – Instances of unrecognized TB
- – Number of AII rooms needed
- – Types of environmental controls needed
Slide 35
TB Risk Assessment (2)
Settings Expecting to Encounter TB Patients
- Identify and address areas with increased transmission
risk
- Ensure prompt recognition and evaluation of M.
tuberculosis transmission in setting
- Conduct periodic reassessments
- Correct lapses in IC
Slide 36
TB Risk Assessment (3)
Settings Not Expecting to Encounter TB
Patients
- Collaborate with health department to review community
TB profile; obtain epidemiologic data for risk assessment
- Determine
- – If any HCWs need to be included in TB screening
program
- – If unrecognized TB occurred in last 5 years
- – Types of controls in place, types needed
Slide 37
TB Risk Assessment (4)
Settings Not Expecting to Encounter TB Patients
- Document steps for prompt recognition and evaluation
of suspected M. tuberculosis transmission
- Conduct periodic reassessments
- Correct any lapses in IC
Slide 38
TB Risk Classifications (1)
All settings should perform risk classification
as part of risk assessment to determine need for and frequency of an
HCW testing program, regardless of likelihood of encountering
persons with TB disease.
Slide 39
TB Risk Classifications (2)
- Low risk – Persons with TB disease not expected to be
encountered; exposure unlikely
- Medium risk – HCWs will or might be exposed to persons
with TB disease
- Potential ongoing transmission – Temporary
classification for any settings with evidence of person-to-person
transmission of M. tuberculosis
Slide 40
TB Risk Classifications (3)
| Inpatient Settings |
Low |
Medium |
Potential
Ongoing Transmission |
| <200 beds |
<3 TB patients/yr |
>3 TB patients/yr |
Evidence of ongoing transmission, regardless of setting |
| ≥200 beds |
<6 TB patients/yr |
>6 TB patients/yr |
Slide 41
TB Risk Classifications (4)
| Outpatient Settings |
Low |
Medium |
Potential Ongoing Transmission |
| TB treatment facilities, medical offices, ambulatory care settings |
<3 TB patients/yr |
>3 TB patients/yr |
Evidence of ongoing transmission, regardless of setting |
Slide 42
TB Risk Classifications (5)
| Nontraditional Facility-based Settings |
Low |
Medium |
Potential Ongoing Transmission |
| Emergency medical service (EMS), medical settings in
correctional facilities, outreach care, long-term care
facilities |
Only patients with LTBI treated No cough-inducing
procedures are performed in setting
System to detect/triage persons with TB symptoms |
Settings where TB patients are expected to be
encountered |
Evidence of ongoing transmission regardless of setting |
Slide 43
TB Risk Classification Example
Small Hospital
- 150-bed hospital in small city
- 2 TB patients admitted in past year
- – 1 placed directly in AII room
- – 1 stayed on medical ward 2 days before AII placement
- Contact investigation showed no evidence of
transmission
Risk classification: Low
Slide 44
Risk Classification Example
Public Health Clinic
- Ambulatory-care setting where TB clinic is held 2
days/week
- In past year, 6 TB patients and 50 LTBI patients
treated
- No evidence of transmission
Risk classification: Medium
Slide 45
Risk Classification Example
Public Hospital
- Large public hospital in big city
- – Average of 150 TB patients/year (35% of city burden)
- – Strong IC program; many AII rooms
- – Annual TST conversion rate among HCWs of 0.5%
- Hospital has strong links with health department
- No evidence of transmission
Risk classification: Medium,
with close ongoing surveillance for episodes of transmission
Slide 46
Risk Classification Example
Prison Setting
- Inpatient area of a correctional facility
- Some inmates are from TB-prevalent countries
- In past year, 2 cases of TB diagnosed in inmates
Risk classification: Medium
Slide 47
Risk Classification Example
Large Hospital
- Big-city hospital with 35 TB patients/year
- TST conversion rate among HCWs of 1.0%
- At annual testing, 3/20 (15%) respiratory therapists
(RTs) had TST conversions
- Problem evaluation
- – The 3 RTs who converted spent time in lab where
induced sputum specimens were collected, and lab venting was
inadequate
Risk classification:
- Potential ongoing transmission for the RTs
- Medium risk for the rest of the setting
Slide 48
Risk Classification Example
Health Maintenance Organization (HMO) Clinic
- Ambulatory-care center associated with a large HMO
where TB rates are highest in the state
- In past year, 1 TB patient presented
- At first visit patient was
- – Recognized as having TB
- – Sent to an emergency department with an AII room
- – Held separately and asked to wear a mask before triage
- Contact investigation showed no evidence of
transmission
Risk classification: Low
Slide 49
Risk Classification Example
HIV-Care Clinic
- Hospital-affiliated HIV clinic serving 2,000 patients
- Has AII room and a TB IC program
- All patients screened for TB at enrollment
- – Those with respiratory complaints placed in AII
- In past year, 7 patients found to have TB
- – All 7 promptly put in an AII room
- – No contact investigation done
- – Annual conversion rate of 0.3% (same as rate in hosp)
Risk classification: Medium
(because of
HIV-infected persons)
Slide 50
Risk Classification Example
Home Care Agency
- Home health-care agency serving a poor area with TB
rates higher than overall community
- Has 125 employees
- – About 30% of workers are foreign-born (FB), many
immigrated within past 5 years
- – Provide nursing, physical therapy, basic home care
- – On baseline 2-step testing, 4 had (+) initial result;
2 had (+) second result (3 of 4 are FB); no TB disease.
- In past year, agency had no TB patients
Risk classification: Low.
Could be medium if FB workers are from TB-prevalent countries,
or large number of clients are HIV infected.
Slide 51
TB Testing Frequency
| Risk classification |
Frequency |
| Low |
Baseline on hire; further testing not needed unless exposure occurs |
| Medium |
Baseline, then annually |
| Potential ongoing transmission |
Baseline, then every 8–10 wks until evidence of transmission has ceased |
Slide 52
Testing HCWs Who Transfer
- All HCWs should receive baseline TB testing
- In IC plans, address HCWs who transfer to another
setting
- Keep all historic testing results; in future, might
need to interpret results of TST vs. QFT-G
Slide 53
TB Testing Frequency for HCWs Who Transfer
| Situation |
Risk Classification Change |
| Low→Low |
Low→Med |
Low or Med → Potential Ongoing Transmission |
| Baseline |
Yes |
Yes |
Yes |
| Routine testing |
No |
Every 12 months |
As needed in investigation |
| After exposure |
Yes, and if TST negative, 8–10 wks after last potential exposure to M. tuberculosis |
Slide 54
Evaluating TB IC Procedures and Identifying
Problems (1)
- Annually evaluate TB IC plan
- Review medical records of a sample of patients with
suspected or confirmed TB disease to find possible problems in TB IC
- Use data from risk assessment worksheet in conducting
review
Slide 55
Evaluating TB IC Procedures and Identifying
Problems (2)
Factors to consider in TB IC evaluation
- Time intervals for all related activities
- Duration of AII precautions
- Extent of meeting criteria for discontinuing AII
precautions
- Patient history of previous admissions
- Adequacy of TB treatment regimens
- Adequacy of sputum collection procedures
- Adequacy of discharge planning
- Number of visits to outpatient setting
Slide 56
Evaluating Environmental Controls (1)
- Determine if recommended environmental controls are in
place by reviewing recent environmental evaluation
- Review environmental control maintenance procedures
and logs
- Use guidelines from American Institute of Architects
(AIA) to review environmental control design specifications
- Evaluate performance of installed system
Slide 57
Evaluating Environmental Controls (2)
- Assess number and type of aerosol-generating
procedures performed in the setting
- Determine if the number of AII rooms is adequate for
the setting based on AIA guidelines and the risk assessment
Slide 58
Suggested Components of Initial TB Training and
Education for HCWs
- Clinical information
- Epidemiology of TB: local, U.S., global
- Recommended IC practices
- TB and conditions of compromised immunity
- Role of public health in TB control
Slide 59
Managing TB Patients: General Recommendations
[Image: health care worker collecting a
sputum sample from a patient]
Slide 60
Prompt Triage
Think TB!
- Primary TB risk to HCWs is patient with undiagnosed or
unrecognized infectious TB
- Promptly initiate AII precautions and manage or
transfer patients with suspected or confirmed TB
- – Ask about and evaluate for TB
- – Check for signs and symptoms
- – Mask symptomatic patients
- – Separate immunocompromised patients
Slide 61
Criteria for Initiating AII Precautions
- Patient has symptoms or signs of TB disease
Or
- Patient has documented infectious TB disease and has
not completed anti-TB treatment
Slide 62
Criteria for Discontinuing AII Precautions
- Infectious TB is unlikely and another diagnosis is
made that explains the syndrome
Or
- Patient has 3 consecutive negative AFB sputum smear
results, and
- Patient has received standard antituberculosis
treatment (minimum of 2 weeks), and
- Patient has demonstrated clinical improvement
Slide 63
Frequency of Sputum Collection for Patients
with Suspected TB Disease
- Three negative sputum smears
- At least 8 hours apart
- At least one collected during early morning
- In most cases, patients with negative sputum smear
results may be released from AII in 2 days
Slide 64
AII Policies and Practices (1)
- AII rooms should be single-patient rooms with a
private bathroom
- Environmental factors and entry of visitors and HCWs
should be controlled to minimize transmission of M. tuberculosis
- HCWs who enter should wear at least N95 disposable
respirators
- Visitors to AII rooms can be offered respiratory
protection and should be instructed in respirator use
Slide 65
AII Policies and Practices (2)
- Diagnose and treat in the AII room
- Ensure patient adheres to AII precautions
- Separate patients with suspected or confirmed
infectious TB disease from HCWs and other patients
- Schedule patients with suspected or confirmed
infectious TB disease for procedures when a minimum number of HCWs
and other patients are present
- Provide a surgical or procedure mask for suspected or
confirmed infectious TB patients during transport, in waiting areas,
and when others are present
Slide 66
AII Room Policies and Practices
- Keep doors closed as much as possible
- Maintain adequate number of AII rooms
- Check room for negative pressure daily when in use
- Group AII rooms together
Slide 67
Clinical Diagnosis
- Obtain medical history and physical exam
- Place patients with suspected or known infectious TB
disease under AII precautions until determined to be noninfectious
- Evaluate persons with extrapulmonary TB for concurrent
pulmonary TB disease
- Although normally not infectious, children should be
evaluated for infectiousness
Slide 68
Laboratory Diagnosis
- Ensure lab personnel are skilled in all aspects of
specimen processing
- Staff should have access to most rapid methods
available and add others as available
- Labs should report positive results to clinicians with
24 hours of obtaining result
- Ensure that labs report drug susceptibility results on M. tuberculosis isolates as soon as they are available, and
that the results are sent to the local or state health department
promptly
Slide 69
AII Precautions for Settings Not
Expecting to Encounter TB Patients
| Setting |
Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Triage only |
Written plan for triage Separate holding area |
As needed in holding areas for suspected/confirmed TB patients |
As needed for HCWs who attend patients during transfer; offer surgical mask to patient if no holding room |
Slide 70
AII Precautions for Settings Expecting to
Encounter TB Patients
| Setting |
Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Patient rooms |
Written AII policies Persons with suspected/ confirmed TB placed in AII room |
≥1 inpatient AII room Air cleaning to increase air changes/ hour (ACH) |
For anyone entering room of patient with suspected/ confirmed infectious TB |
Slide 71
AII Precautions for Inpatient Settings
Emergency Department/Medical Office/Ambulatory-Care Setting
| Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Promptly detect, evaluate, and separate patients with suspected or confirmed TB. |
≥1 AII room for settings with high volume of suspected or confirmed TB patients, or effectively vented room + air cleaning |
At least N95 RP for anyone entering AII rooms of persons with suspected or confirmed infectious TB |
Slide 72
AII Precautions for Inpatient Settings
Intensive Care Units
| Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Place patient with suspected
or confirmed TB in AII room, if possible. |
≥1 AII room for settings with
high volume of suspected or confirmed TB patients.
To prevent contamination risk, place bacterial filter on
vented patient’s endotracheal tube. |
At least N95 RP for anyone who
enters AII rooms of persons with suspected or confirmed
infectious TB. |
Slide 73
AII Precautions for Inpatient Settings
Surgical Suites or Operating Rooms (OR)
| Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Postpone non-urgent procedures on suspected/confirmed TB patients until known to be non-infectious.
Do procedure at end of day and during low traffic times. |
OR anteroom should be either positive pressure relative to both OR and
corridor, or negative relative to both OR and corridor. If no anteroom, keep OR door closed, minimize traffic.
Provide sterile field while preventing contamination with M. tuberculosis. |
Use RP with a valveless filtering facepiece, e.g., N95 disposable. |
Slide 74
AII Precautions for Inpatient Settings
Laboratories
| Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Lab-specific risk assessment and IC plan Biosafety level (BSL) 2 for non-aerosol-producing procedures
Annual HCW M. tuberculosis testing in med. and high-risk settings |
Handle specimens suspected to contain M. tuberculosis and aerosol-producing procedures in
class I or II biological safety cabinet (BSC). |
Lab specific based on risk assessment At least N95. Use if aerosol-producing
procedures performed outside BSC |
Slide 75
AII Precautions for Inpatient Settings
Bronchoscopy Suites
| Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Avoid bronchoscopy on suspected or confirmed TB patients or postpone until
noninfectious. When sputum collection is not possible, use sputum induction. |
AII room or one that meets AII ventilation requirements. In mechanically ventilated
patients, keep circuitry closed. |
At least N95 respiratory protection for HCWs present for bronchoscopy procedures on
patients with suspected or confirmed TB |
Slide 76
AII Precautions for Inpatient Settings
Sputum Induction and Inhalation Therapy Roomss
| Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Use if sputum collection is inadequate.
Use appropriate precautions if patient has suspected or confirmed TB. |
Local exhaust ventilation (e.g., specially vented booth) or room that meets or exceeds
AII requirements |
At least N95 disposable RP for HCWs performing these procedures on a patient with suspected
or confirmed TB |
Slide 77
AII Precautions for Inpatient Settings
Autopsy Suites/Embalming Rooms
| Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| In case of body with suspected or confirmed TB, ensure AII precautions and protection for
those performing autopsies.
Coordinate between attending HCWs and pathologists to ensure proper IC. |
Meet or exceed requirements for AII room.
Exhaust air to outside. |
At least N95 disposable respiratory protection for HCWs performing autopsies on bodies with
suspected or confirmed infectious TB disease |
Slide 78
AII Precautions for Outpatient Settings
TB Treatment Facilities (TB Clinics))
| Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Promptly detect, evaluate, and separate to AII room patients with suspected or confirmed TB.
Ensure separation from HIV-infected patients. Screen HCWs for M. tuberculosis infection.
Schedule treatment of TB patients for certain times or areas away from HIV patients.
Based on risk assessment, ≥1 AII room
for patients with suspected or confirmed TB
Procedures that produce coughs,
aerosols should be performed in booth or AII room. |
Implement respiratory protection
program for HCWs who share space with suspected or confirmed
TB patients. |
Slide 79
AII Precautions for Outpatient Settings
Dialysis Unitss
| Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Written plan for treatment or referral of suspected or confirmed TB patients
Patients with end-stage renal disease should be tested for M. tuberculosis infection.
Separate immuno-compromised dialysis patients from suspected or confirmed TB patients. |
AII room or holding area for hemodialysis patients with suspected or confirmed TB |
At least N95 disposable RP for HCWs entering AII rooms of patients with suspected or confirmed TB |
Slide 80
AII Precautions for Outpatient Settings
Dental Care Settingss
| Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Develop written IC policy based on community risk assessment.
Postpone non-urgent treatment of TB patients. |
AII setting to treat patients with suspected or confirmed infectious TB.
In settings with high volume of suspected or confirmed TB patients, use HEPA units or
ultraviolet germicidal irradiation (UVGI). |
| At least N95 disposable RP for HCWs attending patients with suspected or confirmed TB.
Instruct TB patients to cover cough, wear surgical mask. .
Slide 81
AII Precautions for Nontraditional Settings
Emergency Medical Services (EMS)
| Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Written IC plan Include any exposed EMS staff in contact investigation of TB patients. |
Ambulance vent system should be non-recirculating. Use all available environmental controls to increase number of air changes per hour (ACH). Air should flow from front to back and out.t. |
Consider surgical or procedure masks for suspected or confirmed TB patients and N95 RP for EMS staff. |
Slide 82
AII Precautions for Nontraditional Settings
Medical Settings in Correctional Facilitieses
| Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Develop setting-specific IC
plan.
Test staff for TB annually.
Test inmates for TB and maintain tracking system.
Collaborate with local health department on TB contact
investigations, discharge planning, and training/education
of staff and inmates. |
≥1 AII room based on risk
assessment Place inmates with suspected or confirmed TB in
AII or transfer to AII setting.
Collect sputum in booth, AII room, or outside; not in
cell. |
Implement RP program.
Give surgical mask to inmates who must leave AII room.
Consider N95 RP for staff transporting inmates with
infectious TB.B. |
Slide 83
AII Precautions for Nontraditional Settings
Home Health Carere
| Administrative Controls |
Environmental Controls |
Respiratory Protection Controls |
| Train patients, family re: meds, cough etiquette, medical evaluation. Postpone travel until not infectious. |
No cough-inducing procedures unless infection controls in place |
Consider N95 RP for staff transporting persons with infectious TB. |
Slide 84
AII Precautions for Nontraditional Settings
Long Term Care/Hospice
| Administrative Controls |
| Patients with suspected or confirmed TB should not be
managed or treated unless proper administrative, environmental, and respiratory protection controls in place. |
Slide 85
Training and Educating HCWs
- Initial TB training and educationon
– Provide initial TB training to all HCWs, including
physicians, and document training
- Follow-up TB training and education
- – Annually evaluate the need for follow-up training for HCWs
- – Provide retraining if exposure occurs
- – Provide annual respiratory protection training for HCWs who use respirators
Slide 86
TB Infection Control Surveillance
TB screening programs provide critical info and
consist of
- Baseline testing for M. tuberculosis infection
(new hires)*
- Serial testing for M. tuberculosis infection
- Serial screening for symptoms or signs
- – Clinical evaluation
- – Chest radiograph
- TB training and education
* And other persons who will be tested
periodically (i.e., residents and staff of long term–care facilities
and correctional settings).
Slide 87
Evaluating Problems
- Conduct a contact investigation for problems such as
- – Conversion in TST or BAMT result in HCW
- – TB disease diagnosis in HCW
- – Suspected person-to-person transmission of
M.
tuberculosis
- – IC lapses that expose HCWs to M. tuberculosisis
- – Possible TB outbreaks identified using automated
laboratory systems
Slide 88
Problem Evaluation
Contact Investigation (1)
Objectives of contact investigation:
- Determine likelihood that M. tuberculosis
transmission occurred
- Determine extent of M. tuberculosis
transmission
- Identify persons exposed and, if possible, source of
potential transmission
Slide 89
Problem Evaluation
Contact Investigation (2)
- Identify factors that could have contributed to
transmission
- Implement interventions
- Evaluate effectiveness of interventions
- Ensure that exposure to M. tuberculosis has
been terminated and conditions leading to exposure have been
eliminated
Slide 90
Collaborate with Health Department
- Seek state or local TB program assistance in planning
and implementing TB control activities.
- State or local health department must be notified
about suspected or confirmed TB disease such that follow-up,
community contact investigation, and completion of therapy can be
ensured.
Slide 91
Environmental Controls (1)
- After administrative controls, second line of defense
in TB IC program
- Prevent spread, reduce concentration of infectious
droplet nuclei
- In AII rooms, these systems control airflow direction
to minimize spread of infectious droplet nuclei to adjacent areas
Slide 92
Environmental Controls (2)
- Technologies for removing or inactivating M.
tuberculosis consist of
- – Local exhaust ventilation
- – General ventilation
- – Air-cleaning methods, e.g., high-efficiency
particulate air (HEPA) filtration, ultraviolet germicidal
irradiation (UVGI)
Slide 93
Local Exhaust Ventilation (1)
Slide 94
Local Exhaust Ventilation (2)
- Should remove at least 99% of particles before next
patient or HCW enters
- Use for cough-inducing and aerosol-producing
procedureses
Slide 95
General Ventilation
- Systems that dilute and remove contaminated air and
control airflow patterns in a room
- Single-pass system preferred for AII rooms
- Maintain AII rooms under negative pressure
- – Existing settings: ≥6 air changes/hr (ACH)
- – New or renovated settings: ≥12 ACH
Slide 96
Air-Cleaning Methods
HEPA filters
- Use as supplement to ventilationon
- Used to filter infectious droplet nuclei from
the air
- Must be used
- – When discharging air from local exhaust ventilation
booths directly into surrounding room
- – When discharging air from an AII room into the general
ventilation system
- Can be used to clean air that is exhausted d
to outside
Slide 97
Air-Cleaning Methods
UVGI
- Kills or inactivates M. tuberculosis
- Use as supplement to ventilation
- Not substitute for negative pressure
- Not substitute for HEPA filtration when air
recirculated from AII room into other areas
- Emphasis on safety and maintenancece
- Occupational exposure limits
- – Overexposure can cause damage to skin, eyes
- – UVGI systems must be properly installed and maintained
Slide 98
Respiratory Protection
General
- Third level in the IC hierarchy
- Should be used by persons
- – Entering rooms of suspected/confirmed TB patients
- – Around cough- or aerosol-producing procedures
- – In settings where administrative and environmental
controls will not prevent the inhalation of infectious droplet
nuclei
- Decision on use of respiratory protection (RP) in labs
should be made on case-by-case basis
Slide 99
Respiratory Protection Program (1)
- Settings where HCWs use RP to prevent M.
tuberculosis infection should develop, implement, and maintain
an RP program; include all HCWs who use RP
- Provide HCWs annual training on TB control, IC, and RP
- Give HCWs time to become proficient and comfortable
with respirators
Slide 100
Respiratory Protection Program (2)
- Settings with no AII rooms, no cough- or
aerosol-producing procedures, or no expectations of patients with
suspected or confirmed TB do not need an RP program
- – Have written protocols for recognizing signs or
symptoms of TB and referring or transferring patients to a setting
where they can be manageded
Slide 101
Considerations for Selecting Respirators (1)
- Minimum respiratory protection is a filtering facepiece respirator (nonpowered, air-purifying, half-facepiece,
such as N95 disposable).
- In high-risk situations (cough- or aerosol-producing
activities), additional protection may be needed
Slide 102
Considerations for Selecting Respirators (2)
- Use respirators that also protect HCWs against mucous
membrane exposure to bloodborne pathogens as appropriate
- Use respirators without exhalation valve during
procedures requiring sterile fieldld
- Consider offering respirators (e.g., N95 disposable)
to visitors to AII rooms
Slide 103
Considerations for Selecting Respirators (3)
- In certain settings (e.g., AII rooms, vehicles
carrying infectious patients), administrative and environmental
controls may not be enough to protect HCWs
- Respirator usage regulated by OSHA’s general industry
standard
Slide 104
Respiratory Protection Performance Criteria
- The following can be used for protection against M.
tuberculosis
- – Nonpowered particulate filter respirators certified by
CDC/NIOSH: N-, R-, or P-95, 99, or 100), including disposable
respirators, or powered air-purifying respirators (PAPR) with
high-efficiency filters
- Respirators should fit different face sizes and
features of HCWsWs
Slide 105
Respiratory Protection Performance Criteria
- Respirators must be CDC/NIOSH approved under 42 CFR,
Part 84
- Types of Respiratory Protection
- – Nonpowered air-purifying respirators
- – Powered air-purifying respirators (PAPRs)
- – Supplied-air respirators
Slide 106
Nonpowered Air-Purifying Respirators
| Resistance to
Degradation |
Filter Efficiencies |
| 95 (95%)* |
99 (99%)* |
100 (99.97%)* |
| N (not resistant to oil) |
N95 |
N99 |
N100 |
| R (resistant to oil) |
R95 |
R99 |
R100 |
| P (oil proof) |
P95 |
P99 |
P100 |
Slide 107
Effectiveness of Respiratory Protection Devices
- Face seal fit determines protective ability
- Filter efficiency depends on
- – Filtration characteristics
- – Size distribution of droplets in the aerosol
- – Velocity through the filter
- – Filter loading
- – Electrostatic charges on the filter
Slide 108
Implementing a Respiratory Protection Program
- Assign responsibility
- Train HCWs annually
- Conduct fit testing of HCWs
- – During initial RP program training
- – Periodically thereafter
- Inspect and maintain respirators
- Evaluate program periodically
Slide 109
Cough- and Aerosol-Producing Procedures
Requiring Use of RP
- Cough-producing procedures
- – Endotracheal intubation, suctioning, diagnostic sputum
induction, aerosol treatments, bronchoscopy, laryngoscopy
- – Gastric aspiration and nasogastric intubation can
induce cough in some patients
- Aerosol-producing procedures:
- – Irrigating TB abscesses, homogenizing or lyophilizing
tissue, performing autopsies
Slide 110
Estimating Infectiousness of Patients
[Image: health care worker
looking at a chest x-ray]>
Slide 111
Characteristics of Infectiousness (1)
Infectiousness related to
- – Cough >3 weeks
- – Cavitation on chest radiograph
- – Positive sputum smear results
Slide 112
Characteristics of Infectiousness (2)
- – Respiratory tract disease involving lung, airway, or
larynx
- – Failure to cover mouth and nose when coughing
- – Inadequate treatment
- – Undergoing cough- or aerosol-producing procedures
Slide 113
Discharge to Home
- Patient can be discharged without 3 negative sputum
smears if
- – Follow-up plan has been made with local TB program
- – Patient is on standard treatment and directly observed
therapy (DOT) is arranged
- – No person in home <4 years old or immunocompromised
- – All in household previously exposed
- – Patient willing to stay home until sputum results
negative
- Do not release if high-risk persons will be exposed
Slide 114
Drug-Resistant Disease
- Consider AII precautions for MDR TB patients until
discharge or culture conversion
- – Transmission from MDR TB patients may be extensive
- Risk for transmission not increased in TB/HIV coinfected patients vs. TB patients
Slide 115
Diagnostic Procedures for Latent TB Infection
and TB Disease
[Image: health care worker
measuring induration of a TST]>
Slide 116
Diagnosis of Latent TB Infection
- Persons with LTBI
- – Are asymptomatic
- – Do not feel sick
- – Cannot spread TB to others
- Diagnostic procedures
- – Positive TST with medical evaluation to exclude TB
- Evaluation includes assessing symptoms and signs,
x-ray, and sputum tests
- – Blood assay for M. tuberculosis (BAMT) now
available
Slide 117
Tuberculin Skin Test (1)
- TST is most used test for M. tuberculosis
infection in U.S.
- Improve variable results by HCW training and attention
to detail
- Improve HCW adherence to serial TST by revising
operational policies and HCW training
Slide 118
Tuberculin Skin Test (2)
- Need based on assessment of
- – HCW recent exposure
- – Clinical conditions increasing risk for TB
- – If setting can treat if HCW infected
- Use recommended Mantoux method
- – Training materials available from CDC website:
http://www.cdc.gov/nchstp/tb/pubs/pem.htm
- – Multipuncture (e.g., tine) tests not as reliable
- – Contact HD for additional TST resources
Slide 119
Administering the TST
- Inject 0.1 mL PPD intradermally
- Should produce wheal of 6–10 mm
- Do not recap, bend, break, remove needles from
syringes
- Follow standard IC precautions
[Image: tuberculin skin test]
Slide 120
Reading TST Result
- Read 48–72 hrs after placement
- – If HCW returns after >72 hrs, place and read another
TST*
- – Do not let HCWs read their own results
- Find and measure induration
- – Measure diameter of induration across the arm
- – Do not measure redness
* If the TST reaction is read as ≥15 mm up to
7 days after placement, the result can be considered positive.
[Image: reading a TST result]
Slide 121
Interpreting TST Result (1)
- Probability of positive TST result accuracy depends on M. tuberculosis prevalence in community
- – Low prevalence: low probability of accuracy
- – High prevalence: high probability of accuracy
Slide 122
Interpreting TST Result (2)
Different cut points used depending on
- Patient’s risk for having LTBI
- Size of induration
| >5 mm |
|
highest risk |
| >10 mm |
|
other risk factors |
| >15 mm |
|
no known risk factors |
Slide 123
Interpreting TST for HCWs
| 1. Baseline |
≥10 mm = positive
(≥5 if HCW has HIV) |
| 2. Serial testing |
Increase of ≥10 mm = positive (TST conversion) |
| 3. Known exposure
(contact Investigation) |
≥5 mm = positive when baseline result
is 0 mm; increase of ≥10 mm = positive when baseline
or previous follow-up TST result
is >0 mm, but
<10mm |
Slide 124
Special Considerations in TST
- Anergy
- Antiretroviral therapy for HIV infection
- Pregnancy
- TST boosting
- Use of two-step TST
- BCG vaccination
- Differences in PPD preparations
Slide 125
Anergy
- Anergy is the immune system’s failure to respond to
injected reagents or antigens
- Persons with compromised immunity may not react to
tuberculin
- A few persons with normal immunity also do not react
- Thus, absence of TST reaction does not rule out LTBI
or TB disease
- Anergy testing not recommended as adjunct to TST,
because TST results alone cannot guide clinical decision making
Slide 126
HIV Patients with Reconstituted Delayed-Type
Hypersensitivity (DTH) Response
- HIV patients with initial negative TST result can
convert to positive after starting highly active antiretroviral
therapy (HAART) because of improved immunity
- Should repeat testing for M. tuberculosis
infection in HIV-infected patients with previous negative M.
tuberculosis result after starting HAART
Slide 127
Pregnancy
- No change in guidelines
- No evidence that TST has any adverse effects on
pregnant mother or fetus
- Pregnant HCWs should be included in serial skin
testing; no contraindications
- Postponing diagnosis of M. tuberculosis
infection during pregnancy is unacceptable
Slide 128
TST Boosting
- Some with LTBI have a negative TST reaction when
tested years after infection
- Initial TST may stimulate (boost) ability to react
- Positive reactions to subsequent TSTs could be
misinterpreted as indicating recent infection
Slide 129
TST Two-Step Testing
Used for initial baseline M. tuberculosis
testing for those who will be given TST periodically
- No previous TST: do two-step test
- First test positive: consider TB infected
- First test negative: retest in 1–3 wks (after first TST result was read)
- Second test positive: consider TB infected
- Second test negative: consider not infected
Slide 130
BCG Vaccination
- Not routinely recommended in U.S.
- BCG vaccination not a contraindication to TST
- Can lead to boosting in baseline two-step testing
- – Boosted reaction from previous BCG (false positive) is
indistinguishable from M. tuberculosis reaction (true
positive)
Slide 131
Differences in PPD Preparations (1)
- Two PPD preparations available in U.S.
- – APLISOL®
- – Tubersol®
- Compared to U.S. standard, no differences*
* Villarino ME, Burman W, Wang YC, Lundergan L,
Catanzaro A, Bock N, Jones C, Nolan C. Comparable specificity of 2
commercial tuberculin reagents in persons at low risk for
tuberculosis infection. JAMA 1999:281(2):169-71.
Slide 132
Differences in PPD Preparations (2)
- Compared to each other, APLISOL® produces larger
reactions
- Although difference is slight, might affect positivity
rate in large institutional settings
- Recommend using one product consistently
Slide 133
Use of BAMT Surveillance and LTBI Testing
- LTBI traditionally diagnosed with TST
- Blood assay for M. tuberculosis (BAMT)
available: QFT-Gold
- QFT-G was approved by FDA in 2005 and can be used to
detect LTBI
- – Measures interferon (IFN)-gamma released in blood when
incubated overnight with various reagents, including antigens
specific for M. tuberculosis
- – Lymphocytes from persons with LTBI react to these
proteins by releasing IFN-gamma
Slide 134
Use of BAMT
Benefits of QFT-Gold over TST
- Requires only one patient visit
- Assesses responsiveness to M. tuberculosis
antigens
- Does not boost previous responses
- Interpretation less subjective than for TST
- Probably less affected by BCG vaccination
Slide 135
Use of BAMT
Baseline and Serial Testing
- Baseline testing with BAMT
- – Establish baseline with single negative BAMT result
- – HCWs with positive BAMT result should be referred for
medical and diagnostic evaluation
- Serial testing for infection control
- – A conversion is a change from negative to positive
Slide 136
Special Considerations
- QFT-Gold has not been evaluated in persons aged <17 or
pregnant women
- The BAMT is not affected by the booster phenomenon as
is the TST
- BCG vaccination is not a contraindication to having a
BAMT and does not influence BAMT results
Slide 137
Diagnosing TB Disease
- Chest radiography
- Evaluation of sputum samples
- – Smear
- – Culture
- – Drug susceptibility testing
- Recommend against using bronchoscopy because of risk
of contamination or transmission
Slide 138
Treatment Procedures for LTBI and TB Disease
[Image: prescription pad and pills]
Slide 139
Treatment for LTBI
- Treating LTBI reduces the risk that M. tuberculosis
infection will develop into TB disease
- Certain groups have higher risk for developing TB
disease after infection; should be treated
- Before beginning treatment for LTBI
- – Exclude diagnosis of TB
- – Ensure patient has no history of adverse reactions
resulting from prior LTBI treatment
Slide 140
Candidates for Treatment for LTBI
| Give LTBI Treatment to |
If M. tuberculosis Test Result Is |
Highest risk groups
- Immunocompromised
- Recent contacts
- X-ray indicates previous TB
|
≥5 mm |
Other high-risk groups |
≥10 mm |
Patients with no risks |
≥15 mm |
Slide 141
Treatment Regiments for LTBI
| Drugs |
Months of Duration |
Interval |
Minimum
Doses |
| INH |
9* |
Daily |
270 |
| 2x wkly |
76 |
| INH |
6 |
Daily |
180 |
| 2x wkly |
52 |
| RIF |
4 |
Daily |
120 |
*PreferredINH=isoniazid; RIF=rifampin |
Slide 142
Treatment for TB Disease (1)
- TB treatment regimens must contain multiple drugs to
which M. tuberculosis is susceptible
- Treating TB disease with a single drug can lead to
resistance
- Also, adding a single drug to a failing regimen can
lead to drug resistance
Slide 143
Treatment for TB Disease (2)
- Preferred regimen
- – Initial phase: 2 months isoniazid (INH), rifampin
(RIF), pyrazinamide (PZA), and ethambutol
- – Continuation phase: 4 months INH and RIF
- In patients with cavitary pulmonary TB and positive
culture results at end of initiation phase, continuation phase
should be 7 months
- TB patients with HIV who are taking anti-retrovirals
(ARVs) should be managed by TB/HIV disease experts
- – TB treatment regimens might need to be altered
Slide 144
Cleaning, Disinfecting, and Sterilizing Patient
Rooms (1)
- Three categories of medical equipment: critical, semicritical, and noncritical
- Critical: Instruments introduced directly into
bloodstream or other normally sterile areas (e.g., needles, surgical
instruments) should be sterile at time of use
Slide 145
Cleaning, Disinfecting, and Sterilizing Patient
Rooms (2)
- Semicritical: Do not penetrate body surfaces but might
come into contact with mucous membranes; clean with high-level
disinfectant
- Noncritical: Do not touch patient, or only touch skin;
not associated with transmission
Slide 146
References
Slide 147
Continuing Education Credits (1)
- Continuing education credits will be available until
December 30, 2008
- Participants will receive one of the following:
- – 3.5 hours continuing medical education (CME) credit
- – 0.35 continuing education units (CEUs)
- – 4.0 contact hours continuing nursing education (CNE)
credit
- – 3.5 contact hours National Commission for Health
Education Credentialing (NCHEC) credit
- Participants are required to read and study the
guidelines, take a test, and complete an evaluation
Slide 148
Continuing Education Credits (2)
- If you return the form electronically, you will
receive educational credit immediately.
- If you mail the form, you will receive educational
credit in approximately 30 days.
- No fees are charged for participating in this
continuing education activity.
- MMWR CE Credit:
http://www.cdc/gov/mmwr/cme/conted.html
Slide 149
Additional Resources
For additional information on TB, visit the CDC
Division of Tuberculosis Elimination website at
http://www.cdc.gov/tb
Slide 150
Additional TB Guidelines
- CDC. Prevention and Control of Tuberculosis in
Correctional and Detention Facilities: Recommendations from CDC.MMWR
2006; 55 (No. RR-09): 1–44.
- CDC. Guidelines for the investigation of contacts of
persons with infectious tuberculosis: recommendations from the
National Tuberculosis Controllers Association and CDC. MMWR
2005; 54 (No. RR-15): 1-37.
- CDC. Guidelines for using the QuantiFERON-TB Gold Test
for detecting Mycobacterium tuberculosis infection, United
States. MMWR 2005; 54 (No. RR-15): 49-55.
- CDC. Controlling tuberculosis in the United States:
recommendations from the American Thoracic Society, CDC, and the
Infectious Diseases Society of America. MMWR 2005; 54 (No.
RR-12): 1-81.
- CDC. Guidelines for infection control in dental
health-care settings—2003. MMWR 2003; 52 (No. RR-17).
- CDC. Treatment of tuberculosis. American Thoracic
Society, CDC, and Infectious Diseases Society of America. MMWR
2003; 52 (No. RR-11).
- CDC. Guidelines for environmental infection control in
health-care facilities: recommendations of CDC and the Healthcare
Infection Control Practices Advisory Committee (HICPAC).MMWR
2003; 52 (No. RR-10).
Last Reviewed: 05/18/2008
Content Source: Division of Tuberculosis Elimination
National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention
|
