Return to Slide Set Main Menu
Investigation of Contacts of Persons with Infectious Tuberculosis,
2005
Text Only Version
Slide 1: Investigation of Contacts
of Persons with Infectious Tuberculosis, 2005
National Tuberculosis Controllers Association
Centers for Disease Control and Prevention
Division of Tuberculosis Elimination
Centers for Disease Control and Prevention
Back to Slide Set Main Menu
Slide 2: Background (1)
- 1962: Isoniazid (INH) demonstrated to be effective in preventing
tuberculosis (TB) among household contacts of persons with TB
disease
- Investigation and treatment of contacts with latent TB infection
(LTBI) quickly becomes strategy in TB control and elimination
in the U.S.
- 1976: American Thoracic Society (ATS) published guidelines
for investigation, diagnostic evaluation, and medical treatment
of TB contacts
Back to Slide Set Main Menu
Slide 3: Background (2)
- 2005: National TB Controllers Association (NTCA) and CDC release
guidelines on the investigation of contacts of persons with infectious
TB
- Expanded guidelines on investigation of TB exposure and transmission,
and prevention of future TB cases through contact investigations
- Standard framework for assembling information and using findings
to inform decisions
Back to Slide Set Main Menu
Slide 4: Contact Investigations
– A Crucial Prevention Strategy
Slide 5: Benefits of Contact Investigations
- Finding and treating additional TB disease cases (potentially
interrupting further transmission)
- Finding and treating persons with LTBI to avert future cases
Back to Slide Set Main Menu
Slide 6: Contact Investigation Responsibilities
- Health departments are responsible for ensuring the conduct
contact investigations
- Contact investigations are complicated activities that require
- Many interdependent decisions
- Time-consuming interventions
Back to Slide Set Main Menu
Slide 7: Key Terms (1)
- Case – A particular instance of a disease (e.g., TB).
A case is detected, documented, and reported.
- Contact – Someone who has been exposed to M. tuberculosis
by sharing air space with a person with infectious TB.
Back to Slide Set Main Menu
Slide 8: Key Terms (2)
- Index – The first case or patient who comes to attention
as indicator of a potential public health problem.
- Source case or patient – The case or person who was the
original source of infection for secondary cases or contacts;
can be, but is not necessarily, the index case.
Back to Slide Set Main Menu
Slide 9: Decisions to Initiate a
Contact Investigation
Back to Slide Set Main Menu
Slide 10: Decisions to Initiate
a Contact Investigation
- Public health officials must decide which
- Contact investigations should be assigned a higher priority
- Contacts to evaluate first
- Decision to investigate an index patient depends on presence
of factors used to predict likelihood of transmission
Back to Slide Set Main Menu
Slide 11: Factors that Predict
Likely Transmission of TB
- Anatomical site of the disease
- Positive sputum bacteriology
- Radiographic findings
- Behaviors that increase aerosolization of respiratory secretions
- Age
- HIV status
- Administration of effective treatment
Back to Slide Set Main Menu
Slide 12: Characteristics of the
Index Patient Associated with Increased Risk of TB Transmission
- Pulmonary, laryngeal, or pleural TB
- Acid-fast bacilli (AFB) positive sputum smear
- Cavitation on chest radiograph
- Adolescent or adult patient
- No or ineffective treatment of TB disease
Back to Slide Set Main Menu
Slide 13: Behaviors of the Index
Patient Associated with Increased Risk of TB Transmission
- Frequent coughing
- Sneezing
- Singing
- Close social network
Back to Slide Set Main Menu
Slide 14: Initiating a Contact
Investigation (1)
- Consider if index patient has
- Confirmed or suspected pulmonary, laryngeal, or pleural TB
- Chest radiograph consistent with pulmonary TB
- Recommended if
- Sputum smear has AFB on microscopy
- Chest radiograph indicates presence of cavities in the lung
(AFB sputum smear negative)
Back to Slide Set Main Menu
Slide 15: Initiating a Contact
Investigation (2)
- Not generally indicated if
- Sputum smear has AFB on microscopy and nucleic acid amplification
(NAA) tests for M.tuberculosis are negative
Back to Slide Set Main Menu
Slide 16: Initiating a
Contact Investigation (3)
- Persons with AFB smear or culture-positive sputum and cavitary
TB assigned the highest priority
- Should not be initiated for contacts who have suspected TB disease
and minimal findings in support of pulmonary TB diagnosis
Back to Slide Set Main Menu
Slide 17: Initiating a Contact
Investigation (3)
- Initiation of other investigations depends on
- Availability of resources to be allocated
- Achievement of objectives for higher priority contact investigations
Back to Slide Set Main Menu
Slide 18: Decision to Initiate
a TB Contact Investigation
If the site of disease is pulmonary, laryngeal, or pleural and
the AFB sputum smear is positive and the nucleic acid assay is positive
or not performed, a contact investigation should always be initiated.
If the site of disease is pulmonary, laryngeal, or pleural and
the AFB sputum smear positive and the nucleic acid assay is negative,
a contact investigation is not indicated.
If the site of disease is pulmonary, laryngeal, or pleural and
the AFB sputum smear is negative or not performed and there is cavitary
disease, a contact investigation should always be initiated if there
are sufficient resources.
If the site of disease is pulmonary, laryngeal, or pleural and
the AFB sputum smear is negative or not performed and the chest
radiograph is abnormal indicating non-cavitary consistent with TB,
a contact investigation should be initiated if there are sufficient
resources.
If the site of disease is pulmonary, laryngeal, or pleural and
the AFB sputum smear is negative or not performed and the chest
radiograph is abnormal not consistent with TB, a contact investigation
should be initiated only in exceptional circumstances.
Site of disease - pulmonary suspect (tests pending, e.g., cultures)
and the AFB sputum smear is negative or not performed and there
is cavitary disease, a contact investigation should always be initiated
if there are sufficient resources.
Site of disease - pulmonary suspect (tests pending, e.g., cultures)
and the AFB sputum smear is negative or not performed and the chest
radiograph is abnormal indicating non-cavitary consistent with TB,
a contact investigation should be initiated if there are sufficient
resources.
Site of disease - pulmonary suspect (tests pending, e.g., cultures)
and the AFB sputum smear is negative or not performed and the chest
radiograph is abnormal not consistent with TB, a contact investigation
should be initiated only in exceptional circumstances.
If the site of disease is nonpulmonary (pulmonary and laryngeal
involvement ruled out), a contact investigation is not indicated.
Back to Slide Set Main Menu
Slide 19: Investigating the Index
Patient and Sites of Transmission
Back to Slide Set Main Menu
Slide 20: Comprehensive Index
Patient Information
- Foundation of a contact investigation
- Information to be gathered includes
- Disease characteristics
- Onset time of illness
- Names of contacts
- Exposure locations
- Current medical factors (e.g., initiation of treatment and
drug susceptibility results)
Back to Slide Set Main Menu
Slide 21: Preinterview Phase
- Collect patient background information and circumstances of
illness
- Possible sources include
- Medical record
- Reporting physician
- Match patient’s name to prior TB registries and the surveillance
database
Back to Slide Set Main Menu
Slide 22: Data to Collect in Pre
interview Phase (1)
- History of previous TB exposure or infection
- History of previous TB disease and treatment
- Anatomical sites of TB disease
- Symptoms of illness
- Date of onset
- Chest radiography results
- Other diagnostic imaging study results
Back to Slide Set Main Menu
Slide 23: Data to Collect
in Pre interview Phase (2)
- Histologic or bacteriologic analysis results
- Current bacteriologic results
- Anti-TB chemotherapy regimen
- HIV testing results
- Patient’s concurrent medical conditions
- Other diagnoses that may influence or impinge on the interview
- Identifying demographic information
Back to Slide Set Main Menu
Slide 24: Determining the Infectious
Period
- Focuses investigation on contacts most likely to be at risk
for infection
- Sets time frame for testing contacts
- Information to assist with determining infectious period
- Approximate dates TB symptoms were noticed
- Bacteriologic results
- Extent of disease
Back to Slide Set Main Menu
Slide 25: Start of Infectious
Period
- Cannot be determined with precision; estimation is necessary
- Start is 3 months before TB diagnosis (recommended)
- Earlier start should be used in certain circumstances (e.g.,
patient aware of illness for longer period of time)
Back to Slide Set Main Menu
Slide 26: Estimating the
Beginning of the Infectious Period
Characteristic of Index Case |
|
TB symptoms |
AFB sputum smear positive |
Cavitary chest radiograph |
Likely period of infectiousness |
Yes |
No |
No |
3 months before symptom onset or 1st positive finding consistent
with TB disease, whichever is longer |
Yes |
Yes |
Yes |
3 months before symptom onset or 1st positive finding consistent
with TB disease, whichever is longer |
No |
No |
No |
4 weeks before date of suspected diagnosis |
No |
Yes |
Yes |
3 months before positive finding consistent with TB |
SOURCE: California Department of Health Services
Tuberculosis Control Branch; California Tuberculosis Controllers
Association. Contact Investigation Guidelines. Berkley, CA:
California Department of Health Services; 1998. |
Back to Slide Set Main Menu
Slide 27: Reading the TST (1)
Infectious period closed when all the following criteria are met
- Effective treatment for ≥ 2 weeks,
- Diminished symptoms, and
- Bacteriologic response
Back to Slide Set Main Menu
Slide 28: Exposure Period for
Contacts
Determined by how much time the contact spent with the index patient
during the infectious period
Back to Slide Set Main Menu
Slide 29: Contact Investigation
Interviews
- Establishing trust and rapport with patient is critical
- Interviewers should be trained in interview methods and tutored
on the job
- Conducted in patient’s primary language or in conjunction
with a trained interpreter
- Interviews should be conducted in person in the hospital, TB
clinic, patient’s home, or a convenient location that accommodates
the patients privacy
Back to Slide Set Main Menu
Slide 30: Interviewing the Index
Patient
- Minimum of two interviews should be conducted
- First interview should be conducted
- ≤ 1 business day of reporting for infectious patients
- ≤ 3 business days for others
- Second interview conducted 1–2 weeks later
- Additional interviews depend on the amount of information needed
and time to develop rapport with patient
Back to Slide Set Main Menu
Slide 31: Contact Investigation
Interview General Principles
- Establish rapport with patient
- Exchange information
- Review transmission settings
- Record sites of transmission
- Compile list of contacts
- Provide closure
- Conduct follow-up interviews, if needed
Back to Slide Set Main Menu
Slide 32: Proxy Interviews
- Can build on the information provided by index patient
- Essential when patient cannot be interviewed
- Conducted with key informants most likely to know the patients’
practices, habits, and behaviors
- Jeopardizes patient confidentiality
Back to Slide Set Main Menu
Slide 33: Field Investigation
(Site Visits)
- Site visits are complementary to interviewing
- Should be made ≤ 3 days of the initial
interview
- Elicits additional contact information; especially helpful
for finding children
- Lack of site visits has contributed to TB outbreaks
Back to Slide Set Main Menu
Slide 34: Follow-up Steps
- Continuing investigation is shaped by reassessments of ongoing
results
- Notification and follow-up communication with other jurisdictions
should be arranged for out-of-area contacts
Back to Slide Set Main Menu
Slide 35: Specific Investigation
Plan
- Investigation plan should include
- Information gathered in interviews and site visits
- Registry of contacts and their assigned priorities
- Written timeline for monitoring the investigation progress
- Data recorded on standardized forms
- Part of the permanent medical record
Back to Slide Set Main Menu
Slide 36: Time Frames for
Initial Follow-up of Contacts Exposed to TB
Type of Contact |
Business days from listing of a contact to initial encounter*
|
Business days from initial encounter to completion of medical
evaluation† |
High priority contact: index case AFB sputum smear positive
or cavitary disease on chest x-ray |
7 |
5 |
High priority contact: index case AFB sputum smear negative§ |
7 |
10 |
Medium priority contact: regardless of AFB sputum smear or
culture result |
14 |
10 |
*A face-to-face meeting that allows the health
care worker to assess the overall health of the contact, administer
a TST, and schedule further evaluation. †The medical
evaluation is complete when the contact’s status (LTBI
or TB disease) is determined. §Abnormal chest x-ray
consistent with TB disease, might be NAA positive and /or AFB
culture positive |
SOURCE: California Department of Health Services
Tuberculosis Control Branch; California Tuberculosis Controllers
Association. Contact Investigation Guidelines. Berkley, CA:
California Department of Health Services; 1998. |
Back to Slide Set Main Menu
Slide 37: Assigning Priorities
to Contacts
Back to Slide Set Main Menu
Slide 38: Assigning Priorities
to Contacts (1)
- Priorities should be assigned to contacts and resources allocated
to complete all investigative steps for high-and medium-priority
contacts.
- Any contact not classified as high or medium priority is assigned
a low priority.
Back to Slide Set Main Menu
Slide 39: Assigning Priorities
to Contacts (2)
- Priorities based on likelihood of infection and hazards to
the contact if infected
- Priority scheme directs resources to contacts who
- Have secondary case of TB disease
- Have recent M. tuberculosis infection (most likely to benefit
from treatment)
- Are most likely to develop TB disease if infected or could
suffer severe morbidity if they develop TB disease
Back to Slide Set Main Menu
Slide 40: Factors for Assigning
Contact Priorities
- Characteristics of the index patient
- Characteristics of contacts
- Age
- Immune status
- Other medical conditions
- Exposure
Back to Slide Set Main Menu
Slide 41: Prioritization of Contacts
(1)
Patient has pulmonary, laryngeal, or pleural TB with cavitary lesion
on chest radiograph or is AFB sputum smear positive
Household contact |
High |
Contact < 5 years of age |
High |
Contact with medical risk factor (HIV or other medical risk
factor) |
High |
Contact with exposure during medical procedure (bronchoscopy,
sputum induction, or autopsy) |
High |
Contact in a congregate setting |
High |
Contact exceeds duration/environment limits (limits per unit
time established by the health department for high-priority
contacts) |
High |
Contact is ≥ 5 years and ≤ 15 years of age |
Medium |
Contact exceeds duration/environment limits (limits per unit
time established by the health department for medium-priority
contacts) |
Medium |
Any contact not classified as high or medium priority is assigned
a low priority.
Back to Slide Set Main Menu
Slide 42: Prioritization
of Contacts (2)
Patient is a suspect or has confirmed pulmonary/pleural TB –
AFB smear negative, abnormal chest radiograph consistent with TB
disease, may be NAA and/or culture positive
Contact < 5 years of age |
High |
Contact with medical risk factor (e.g., HIV) |
High |
Contact with exposure during medical procedure (bronchoscopy,
sputum induction, or autopsy) |
High |
Household contact |
Medium |
Contact exposed in congregate setting |
Medium |
Contact exceeds duration/environment limits (limits per unit
time established by the local TB control program) |
Medium |
Any contact not classified as high or medium priority is assigned
a low priority.
Back to Slide Set Main Menu
Slide 43:
Prioritization of Contacts (3)
Patient is a suspect pulmonary TB case – AFB smear negative,
NAA negative/culture negative, abnormal chest radiograph not consistent
with TB disease
Household contact
|
Medium |
Contact < 5 years of age
|
Medium |
Contact with medical risk factor (e.g., HIV infection or other
immunocompromising condition)
|
Medium |
Contact with exposure during medical procedure (bronchoscopy,
sputum induction, or autopsy)
|
Medium |
Any contact not classified as high or medium priority
is assigned a low priority. |
Back to Slide Set Main Menu
Slide 44: Diagnostic
and Public Health Evaluation of Contacts
Back to Slide Set Main Menu
Slide 45: Initial Assessment of
Contacts
- Should be accomplished within 3 working days of the contact
having been listed in the investigation
- Gathers background health information
- Permits face-to-face assessment of person’s health
Back to Slide Set Main Menu
Slide 46: Information to Collect
During Initial Assessment (1)
- Previous M. tuberculosis infection or disease and related treatment
- Contact’s verbal report and documentation of previous
TST results
- Current symptoms of TB illness
Back to Slide Set Main Menu
Slide 47: Information to Collect During Initial
Assessment (2)
- Medical conditions making TB disease more likely
- Mental health disorders
- Type, duration, and intensity of TB exposure
- Sociodemographic factors
Back to Slide Set Main Menu
Slide 48: Information to Collect During
Initial Assessment (3)
- HIV status; contacts should be offered HIV counseling and testing
if status unknown
- Information regarding social, emotional, and practical matters
that might hinder participation
Back to Slide Set Main
Menu
Slide 49: Reassess Strategy After Initial
Information Collected
After initial information collected
- Priority assignments should be reassessed
- Medical plan for diagnostic tests and possible treatment can
be formulated for high- and medium-priority contacts
Back to Slide
Set Main Menu
Slide 50: Tuberculin Skin Testing
- All high or medium priority contacts who do not have a documented
previous positive tuberculin skin test (TST) or previous TB disease
should receive a TST at the initial encounter.
- If not possible, TST should be administered
≤ 7 working days of listing high-priority
contacts
≤ 14 days of listing medium-priority contacts
Back to Slide Set Main
Menu
Slide 51: Interpreting Skin Test Reaction
- ≥ 5 mm induration is positive for any contact
- Two-step procedure should not be used for testing contacts
- A contact whose second TST is positive after initial negative
result should be classified as recently infected
Back to Slide Set Main
Menu
Slide 52: Post exposure Tuberculin Skin
Testing
- Window period is 8–10 weeks after exposure ends
- Contacts who have a positive result after a previous negative
result are said to have had a change in tuberculin status from
negative to positive
Back to Slide Set Main Menu
Slide 53: Medical Evaluation
All contacts whose skin test reaction induration is mm
or who report any symptoms consistent with TB disease should undergo
further examination and testing for TB
Back to Slide Set Main Menu
Slide 54: Evaluation and Follow-up of
Children <5 Years of Age
- Always assigned a high priority as contacts
- Should receive full diagnostic medical evaluation, including
a chest radiograph
- If TST ≤ 5 mm of induration and last exposure < 8
weeks, LTBI treatment recommended (after TB disease excluded)
- Second TST 8–10 weeks after exposure; decision to treat
is reconsidered
- Negative TST – treatment discontinued
- Positive TST – treatment continued
Back to Slide Set Main
Menu
Slide 55: Evaluation and Follow-up of
Immunosuppressed Contacts
- Should receive full diagnostic medical evaluation, including
a chest radiograph
- If TST negative ≥ 8 weeks after end of exposure, full
course of treatment for LTBI recommended (after TB disease is
excluded)
Back to Slide Set Main Menu
Slide 56: Medical Treatment for Contacts
with LTBI
Back to Slide Set Main
Menu
Slide 57: Health Department Responsibilities
- Focusing resources on contacts in most need of treatment
- Monitoring treatment, including that of contacts who receive
care outside the health department
- Providing directly observed therapy (DOT), incentives, and
enablers
Back to Slide Set Main Menu
Slide 58: Decision to treat contacts with
a negative skin test result should take the following factors into
consideration
- The frequency, duration, and intensity of exposure
- Corroborative evidence of transmission from the index patient
Back to Slide Set Main Menu
Slide 59: Prophylactic Treatment
Prophylactic treatment (after TB disease is excluded) of presumed
M. tuberculosis infection recommended for persons
- With HIV infection
- Taking immunosuppressive therapy for organ transplant
- Taking anti-tumor necrosis factor alpha (TNF-a) agents
Back to Slide Set Main
Menu
Slide 60: Treatment After Exposure to
Drug-Resistant TB
- Consultation with physician with MDR expertise recommended for
selecting a LTBI regimen
- Contacts should be monitored for 2 years after exposure
Back to Slide Set Main
Menu
Slide 61: Selecting Contacts for Directly Observed
Therapy
- Contacts aged < 5 years
- Contacts who are HIV infected or otherwise substantially immunocompromised
- Contacts with a change in their tuberculin skin test status
from negative to positive
- Contacts who might not complete treatment because of social
or behavior impediments
Back to Slide Set Main
Menu
Slide 62: When to Expand a Contact Investigation
Back to Slide Set Main Menu
Slide 63: Determining When to Expand a
Contact Investigation
- Consideration of the following factors recommended
- Achievement of program objectives with high- and medium-priority
contacts
- Extent of recent transmission
- Unexpectedly large rate of infection or TB disease in high-priority
contacts
- Evidence of second-generation transmission
- TB disease in any contacts who had been assigned low priority
- Infection in any contacts aged < 5 years
- Contacts with change in skin test status from negative to
positive
Slide 64: Strategy for Expanding a Contact
Investigation
- Should be based on the investigation data
- Results should be reviewed weekly
- In absence of recent transmission, investigation should not
be expanded to lower-priority groups
Back to Slide Set Main Menu
Slide 65: Communicating Through the News
Media
Back to Slide Set Main Menu
Slide 66: Possible Situations
for News Coverage
Certain contact investigations have the potential for sensational
news coverage. Examples include
- Involving numerous contacts (especially children)
- Occurring in public settings
- Occurring in workplaces
- Associated with TB fatalities
- Associated with drug-resistant TB
Back to Slide Set Main Menu
Slide 67: Reasons for Participating in
News Media Coverage (1)
- Educates the public regarding the nature of TB
- Reminds public of continued presence of TB
- Provides a complementary method to alert exposed contacts of
the need for seeking medical evaluation
- Relieves unfounded public fears regarding TB
Back to Slide Set Main Menu
Slide 68: Reasons for Participating in
News Media Coverage (2)
- Illustrates the health department’s leadership in communicable
disease control
- Ensures that constructive public inquiries are directed to
the health department
- Validates the need for public resources to be directed to disease
control
Back to Slide Set Main Menu
Slide 69: Potential Drawbacks to News
Coverage
- Increase public anxiety
- Cause unexposed person seeking unnecessary medical care
- Contribute to unfavorable views of the health department
- Contribute to spread of misinformation
- Trigger unconstructive public inquiries
- Unintended disclosure of confidential information
Back to Slide Set Main Menu
Slide 70: Strategy for News Coverage
- Anticipatory preparation of clear media messages is recommended
- Develop communication objectives
- Issue news release in advance of any other media coverage
- Collaborate with partners outside of the health department
Back to Slide Set Main Menu
Slide 71: Data Management and Evaluation
of Contact Investigations
Back to Slide Set Main Menu
Slide 72: Data Collection
Three broad purposes in contact investigations
- Management of care and follow-up index patients and contacts
- Epidemiologic analysis of investigation in progress and investigations
overall
- Program evaluation using performance indicators that reflect
performance objectives
Back to Slide Set Main Menu
Slide 73: Reasons Contact Investigation
Data are Needed
- Presents broad amount of demographic, epidemiologic, historic,
and medical information needed to provide comprehensive care
- Provides information on process steps necessary for monitoring
timeline objectives
- Provides information needed to reassess investigation strategy
Back to Slide Set Main Menu
Slide74: Confidentiality and Consent in
Contact Investigations
Back to Slide Set Main Menu
Slide 75: Safeguarding Confidentiality
- Challenging and difficult during contact investigations
- Essential to maintaining credibility and trust
- Constant attention required to maintain confidentiality
- Specific policies for release of confidential information related
to contact investigations are recommended
Back to Slide Set Main Menu
Slide 76: Confidentiality and Consent
TB control programs should address the following confidentiality
and consent issues before initiation of contact investigations
- Contact investigation policies and training
- Informed consent
- Site investigations
- Other medical conditions besides TB
Back to Slide Set
Main Menu
Slide 77: Staffing and Training for Contact
Investigations
Back to Slide Set Main Menu
Slide 78: Staffing and
Training for Contact Investigations
- Contact investigations involve personnel in the health department
and other health care delivery systems
- Contact investigation tasks require multiple functions and
skills
- Training is essential for successful contact investigations
Back to Slide Set Main Menu
Slide 79: Contact Investigations
in Special Circumstances
Back to Slide Set Main Menu
Slide 80: Definition
of an Outbreak
- During (and because of) a contact investigation, 2 or more contacts
are found to have active TB, regardless of their assigned priority;
or
- Any 2 or more cases occurring within a year of each other,
discovered to be linked, and the linkage is established outside
of a contact investigation
Back to Slide Set Main Menu
Slide 81: TB Outbreaks
A TB outbreak is a sign of extensive transmission
and implies that
- A TB patient was contagious
- Contacts were exposed for a substantial period of time
- The interval since exposure has been sufficient for infection
to progress to disease (interval may be shortened by HIV infection)
Back to Slide Set Main Menu
Slide 82: Develop Outbreak
Strategy Based on Risk Factors
- Contagious TB undiagnosed or untreated for an extended period,
or an extremely contagious case
- Source patient visiting multiple sites
- Patient and contacts in close or prolonged company
- Environment promoting transmission
- Contacts very susceptible to disease after M. tuberculosis
infection
- Gaps in contact investigations and follow-up
- Extra-virulent strain of M.tuberculosis
Back to Slide Set Main Menu
Slide 83: Congregate
Settings
Concerns associated with congregate settings
- Substantial number of contacts
- Incomplete information regarding contact names and locations
- Incomplete data for determining priorities
- Difficulty in maintaining confidentiality
- Collaboration with officials and administrators who are unfamiliar
with TB
- Legal implications
- Media coverage
Back to Slide Set Main Menu
Slide 84: Congregate
Settings – Designating Priorities
- Site specific
- Customized algorithm required for each situation
- Source-case characteristics
- Duration and proximity of exposure
- Environmental factors that modify transmission
- Susceptibility of contacts
Back to Slide Set Main Menu
Slide 85: Congregate
Settings - Setting-Based Investigation
- Interview and test contacts on site is optimum approach
- Alternative is evaluation at the health department with additional
personnel and extended hours
- As last resort, notify contacts in writing to seek diagnostic
evaluation with their own health care provider
Back to Slide Set Main Menu
Slide 86: Correctional
Facilities
- Establish preexisting formal collaboration between correctional
and public health officials
- Trace high-priority contacts who are transferred, released,
or paroled before medical evaluation for TB
- Low completion rate is anticipated unless follow-through supervision
can be arranged for released or paroled inmates
Back to Slide Set Main Menu
Slide 87: Workplaces
- Duration and proximity of exposure can be greater than for other
settings
- Details to gather from index patient during initial interview
include
- Employment hours
- Working conditions
- Workplace contacts
- Occasional customers of workplace should be designated as low
priority
Slide 88: Hospitals and
Other Health-Care Settings
- Personnel collaborating with hospitals and other health-care
agencies should have knowledge of legal requirements
- Plan investigation jointly with health department and setting
(division of responsibilities)
- Majority of health-care settings have policies for testing
employees for M. tuberculosis infection
Back to Slide Set Main Menu
Slide 89: Schools
- Early collaboration with school officials and community members
is recommended
- Issues of consent, assent, and disclosure of information more
complex for minors
- Site visits should be conducted to check indoor spaces, observe
general conditions, and interview maintenance personnel regarding
ventilation
Slide 90: Shelters and
Other Settings Providing Services for Homeless Persons
- Challenges include
- Locating the patient and contacts if mobile
- Episodic incarceration
- Migration from one jurisdiction to another
- Psychiatric illnesses
- Preexisting medical conditions
- Site visits and interviews are crucial
- Work with setting administrators to offer onsite supervised
intermittent treatment
Back to Slide Set Main Menu
Slide 91: Interjurisdictional
Contact Investigations
- Requires joint strategies for finding contacts, having them
evaluated, treating infected contacts, and gathering data
- Health department that counts index patient is responsible
for leading the investigation and notifying health departments
in other jurisdictions
Back to Slide Set Main Menu
Slide 92: Source-Case
Investigations
Back to Slide Set Main Menu
Slide 93: Source-Case
Investigations
- Seeks the source of recent M.tuberculosis infection
- In the absence of cavitary disease, young children usually
do not transmit M.tuberculosis to others
- Recommended only when TB control program is achieving its objectives
when investigating infectious cases
Back to Slide Set Main Menu
Slide 94: Child with
TB Disease
- Source-case investigations considered for children <5 years
of age
- May be started before diagnosis of TB confirmed
Back to Slide Set Main Menu
Slide 95: Child with
LTBI
- Search for source of infection for child is unlikely to be productive
- Recommended only with infected children < 2 years of age,
and only if data are monitored to determine the value of the investigation
Back to Slide Set Main Menu
Slide 96: Procedures for
Source-Case Investigation
- Same procedure as standard contact investigation
- Patient or guardians best informants (associates)
- Focus on associates who have symptoms of TB disease
- Should begin with closest associates
Back to Slide Set Main Menu
Slide 97: Data collection
Data needed for assessing the productivity of source-case
investigations
- Number of index patients investigated for their sources
- Number of associates screened for TB disease
- Number of times a source is found
Back to Slide Set Main Menu
Slide 98: Cultural Competency
and Social Network Analysis
Back to Slide Set Main Menu
Slide 99: Cultural Competence
- Knowledge and interpersonal skills that allow health-care providers
to appreciate and work with persons from cultures other than their
own
- Ability to understand cultural norms and to bridge gaps requires
training and experience
Back to Slide Set Main Menu
Slide 100: Social Network
Analysis
- Social Network – linkage of persons and places where M.
tuberculosis is spread via shared air space
- Social Network Analysis – methodology of visualizing
and quantitating the relative importance of members in a social
network
- Social Network Analysis assumes there is some detectable patterning
of the TB cases and their contacts in a community
Back to Slide Set Main Menu
Slide 101: Personal
Networks for Two TB Cases
Diagram showing the personal networks for two TB
cases. Personal network for Bill includes Juan, Rose and Ted. The
personal network for Rita includes Ted, Moe, and Ali.
Back to Slide Set Main Menu
Slide 102: Combined:
A Social Network
Diagram showing the combined personal networks for Bill and Rita,
with the link between the two being Ted. Allows review of multiple
rather than individual personal networks.
Allows review of multiple rather than individual personal
networks
Back to Slide Set Main Menu
Slide 103: Combined:
A Social Network with Place
Diagram showing the combined personal networks for
Bill and Rita with the addition of a location, Mel's bar.
Back to Slide Set Main Menu
Slide 104: Social Network
Analysis – Approach (1)
- Provides a systematic method to deal with data already gathered
in routine contact investigations
- Analysis of the network can help identify important contacts
(i.e., those most likely to be infected)
- Real-time monitoring of network growth may facilitate early
detection of outbreaks
Back to Slide Set Main Menu
Slide 105: Social Network
Analysis – Approach (2)
- May help programs focus control efforts
- May offer effective way to list contacts and assign priorities
- Has been tested retrospectively on TB outbreak and contact
investigations
Back to Slide Set Main Menu
Slide 106: Reference
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)
http://www.cdc.gov/mmwr/pdf/rr/rr5415.pdf
Back to Slide Set Main Menu
Slide 107: Continuing
Education Credits (1)
- Participants will be able to receive one of the following
- Continuing Medical Education (CME) credit Continuing Medical
Education (CME) credit –
- Continuing Nursing Education (CNE) credit Continuing Nursing
Education (CNE) credit –
- Continuing Education Unit (CEU) Continuing Education Unit
(CEU) –
- Certified Health Education Specialist (CHES) credit Certified
Health Education Specialist (CHES) credit –
- Participants are required to read and study the guidelines,
take a test, and complete an evaluation.
Back to Slide Set Main Menu
Slide 108: Continuing
Education Credits (2)
Back to Slide Set Main Menu
Slide 109: Additional
Resources
For additional information on TB, visit the CDC Division
of Tuberculosis Elimination Website
Guidelines Available Online
CDC’s Morbidity and Mortality
Weekly Report
Back to Slide Set Main Menu
Last Reviewed: 05/18/2008 Content Source: Division of Tuberculosis Elimination
National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention
|