Guidelines for Preventing Transmission of TB in the Health-Care Setting
The following policy is based on a low risk TB assessment and was derived from the Center for Disease Control's:
Guidelines for Preventing the Transmission of Mycobacterium tuberculosis in Health-Care Settings, 2005, which were
released in December of 2005. For the full article please see http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5417a1.htm
The term 'tuberculin skin tests' (TSTs) is used instead of purified protein derivative (PPD).
The frequency of TB screening for Health Care Workers (HCW)s
has been decreased in various settings, and the criteria for
determination of screening frequency have been changed.
The scope of settings in which the guidelines apply has been
broadened to include laboratories and additional outpatient
and nontraditional facility based settings.
Criteria for serial testing for M. tuberculosis infection of
HCWs are more clearly defined. In certain settings, this
change will decrease the number of HCWs who need serial TB
These recommendations usually apply to an entire health-care
setting rather than areas within a setting.
New terms, airborne infection precautions (airborne
precautions) and airborne infection isolation room (AII
room), are introduced.
Recommendations for annual respirator training, initial respirator fit testing, and periodic respirator fit testing
have been added. The evidence of the need for respirator fit testing is summarized.
Information on ultraviolet germicidal irradiation (UVGI) and room-air recirculation units has been expanded.
Additional information regarding MDR TB and HIV infection has been included.
Outpatient settings include TB treatment facilities, medical offices, ambulatory-care settings, dialysis units, and
HCWs Who Should Be Included in a TB Surveillance Program
HCWs refer to all paid and unpaid persons working in
health-care settings who have the potential for exposure to
M. tuberculosis through air space shared with persons with
infectious TB disease. Part time, temporary, contract, and
full-time HCWs should be included in TB screening programs.
All HCWs who have duties that involve face to-face contact
with patients with suspected or confirmed TB disease
(including transport staff) should be included in a TB
In addition to close contacts, the following persons are also
at higher risk for exposure to and infection with M.
tuberculosis. Persons listed who are also close contacts
should be top priority.
Foreign-born persons, including children, especially those
who have arrived to the United States within 5 years after
moving from geographic areas with a high incidence of TB
disease (e.g., Africa, Asia, Eastern Europe, Latin America,
and Russia) or who frequently travel to countries with a high
prevalence of TB disease.
Residents and employees of congregate settings that are high
risk (e.g., correctional facilities, long-term--care
facilities [LTCFs], and homeless shelters).
HCWs who serve patients who are at high risk.
HCWs with unprotected exposure to a patient with TB disease
before the identification and correct airborne precautions of
Certain populations who are medically underserved and who
have low income, as defined locally.
Populations at high risk who are defined locally as having an
increased incidence of TB disease.
Infants, children, and adolescents exposed to adults in
Fundamentals of TB Infection Control
One of the most critical risks for health-care--associated
transmission of M. tuberculosis in health-care settings is
from patients with unrecognized TB disease who are not
promptly handled with appropriate airborne precautions.
All health-care settings need a TB infection control program
designed to ensure prompt detection, airborne precautions,
and treatment of persons who have suspected or confirmed TB
disease (or prompt referral of persons who have suspected TB
disease for settings in which persons with TB disease are not
expected to be encountered).
TB Infection-Control Program
Every health-care setting should have a TB infection control
plan that is part of an overall infection control program.
The specific details of the TB infection control program will
differ, depending on whether patients with suspected or
confirmed TB disease might be encountered in the setting or
whether patients with suspected or confirmed TB disease will
be transferred to another health-care setting. Staff charged
with making this distinction should obtain medical and
epidemiologic consultation from state and local health
TB Infection-Control Program for Settings in Which Patients
with Suspected or Confirmed TB Disease Are Not Expected To Be
TB Risk Assessment
Every health-care setting should conduct initial and ongoing
evaluations of the risk for transmission of M. tuberculosis,
regardless of whether or not patients with suspected or
confirmed TB disease are expected to be encountered in the
setting. The TB risk assessment determines the types of
administrative, environmental, and respiratory protection
controls needed for a setting and serves as an ongoing
evaluation tool of the quality of TB infection control and
for the identification of needed improvements in infection
TB Risk Assessment for Settings in Which Patients with
Suspected or Confirmed TB Disease Are Not Expected To Be
The initial and ongoing risk assessment for these settings
should consist of the following steps:
1. Review the community profile of TB disease in
collaboration with the local or state health department.
2. Consult the local or state TB control program to obtain
epidemiologic surveillance data necessary to conduct a TB
risk assessment for the health-care setting.
3. Determine if persons with unrecognized TB disease were
encountered in the setting during the previous 5 years.
4. Determine if any HCWs need to be included in the TB
5. Determine the types of environmental controls that are
currently in place, and determine if any are needed in
the setting (see Environmental Controls; Appendices A and
6. Document procedures that ensure the prompt recognition
and evaluation of suspected episodes of health-care--
associated transmission of M. tuberculosis.
7. Conduct periodic reassessments (annually, if possible) to
ensure 1) proper implementation of the TB
infectioncontrol plan; 2) prompt detection and evaluation
of suspected TB cases; 3) prompt initiation of airborne
precautions of suspected infectious TB cases before
transfer; 4) prompt transfer of suspected infectious TB
cases; 5) proper functioning of environmental controls,
as applicable; and 6) ongoing TB training and education
8. Recognize and correct lapses in infection control.
Use of Risk Classification to Determine Need for TB
Screening and Frequency of Screening HCWs
Risk classification should be used as part of the risk
assessment to determine the need for a TB screening program
for HCWs and the frequency of screening
TB Screening Risk Classifications
The three TB screening risk classifications are low risk,
medium risk, and potential ongoing transmission. The
classification of low risk should be applied to settings in
which persons with TB disease are not expected to be
encountered, and, therefore, exposure to M. tuberculosis is
unlikely. This classification should also be applied to HCWs
who will never be exposed to persons with TB disease or to
clinical specimens that might contain M. tuberculosis.
The classification of medium risk should be applied to
settings in which the risk assessment has determined that
HCWs will or will possibly be exposed to persons with TB
disease or to clinical specimens that might contain M.
The classification of potential ongoing transmission should
be temporarily applied to any setting (or group of HCWs) if
evidence suggestive of personto-person (e.g.,
patient-to-patient, patient-to-HCW, HCWto-patient, or
HCWto-HCW) transmission of M. tuberculosis has occurred in
the setting during the preceding year. Evidence of
personto-person transmission of M. tuberculosis includes 1)
clusters of TST or BAMT conversions, 2) HCW with confirmed TB
disease, 3) increased rates of TST (tuberculin skin test) or
BAMT (blood assay for M. tuberculosis)conversions, 4)
unrecognized TB disease in patients or HCWs, or 5)
recognition of an identical strain of M. tuberculosis in
patients or HCWs with TB disease identified by
deoxyribonucleic acid (DNA) fingerprinting.
If uncertainty exists regarding whether to classify a setting
as low risk or medium risk, the setting typically should be
classified as medium risk.
TB Screening Procedures for Settings (or HCWs) Classified as
All HCWs should receive baseline TB screening upon hire,
using two-step TST or a single BAMT to test for infection
with M. tuberculosis. After baseline testing for infection
with M. tuberculosis, additional TB screening is not
necessary unless an exposure to M. tuberculosis occurs.
HCWs with a baseline positive or newly positive test result
for M. tuberculosis infection (i.e., TST or BAMT) or
documentation of treatment for LTBI or TB disease should
receive one chest radiograph result to exclude TB disease (or
an interpretable copy within a reasonable time frame, such as
6 months). Repeat radiographs are not needed unless symptoms
or signs of TB disease develop or unless recommended by a
Although this organization classifies itself as a low risk
for TB, should a case every be discovered in this setting the
following will occur:
1. Perform an investigation in collaboration with the local
or state health department if health-care--associated
transmission of the M. tuberculosis case.
2. Collaborate with the local or state health department to
develop administrative controls consisting of the risk
assessment and the written TB infection control plan.
Approved By Governing Board