Presentation on theme: "USAPHC, Army Public Health Nursing Staff Officer"— Presentation transcript:
1USAPHC, Army Public Health Nursing Staff Officer Conducting Contact Investigations for Tuberculosis July Epi-Tech TrainingLakisha Flagg, MAJ, ANUSAPHC, Army Public Health Nursing Staff Officer
2Learning Objectives Define a TB contact interview/investigation Determine when to initiate a contact investigationReview of TB Contact Investigation Procedures (“10 Steps”)Identify relevant information sourcesEstimate period of infectivityInterview CaseDevelop plan for investigationRefine estimatesPrioritize contactsConducting field visitsConduct contact interviewsInterview expansionProcess evaluationDescribe basic communication requirementsDescribe data collection process and goal of data management
3What is a TB Contact Interview/Investigation Systematic process of case/contact:IdentificationAssessmentTreatmentPurposeInteraction with suspected or confirmed TB casesInformation gathering, education, and knowledge reinforcementEssential component of TB controlIdentification and treatment of contactsFacilitate prevention of TB transmission
4Components of a TB Contact Investigation Pre-InterviewData collectionEstablish priority of interviewsDetermination of infectious widowInterviewContinued data collection/contact identificationAssessmentEducationCollaborationFollow – UpOngoing Collaboration & Process EvaluationPulmonary, laryngeal, pleuralBehavior – cough, singing, close social networkThe TB interview is initiated to identify contacts at risk of exposure to refer for medical evaluation for TB infection or disease. Because of this goal, only certain patients need to be interviewed. These include patients whoHave been diagnosed with verified TB (excluding most forms of extrapulmonary TB, but including pleural effusion or miliary TB with cough and laryngeal TB);Are suspected of having pulmonary, laryngeal, or pleural TB;Have been diagnosed with any form of verified TB, abnormal chest x-ray, positive tuberculin skin test which indicates recent TB transmission (for example, a documented converter who has developed disease or a young child).The TB interview is conducted with individuals who may have put others at risk of contracting TB. In addition, if there is evidence of recent TB transmission, a source case investigation may be initiated. Like a contact investigation, this process attempts to locate a patient’s contacts, referred to as associates. In this case, the associate is viewed as the “source,” or the person who transmitted TB infection and not the recipient of TB infection due to prolonged exposure to the index case. For this reason, it is recommended that interviews be conducted with the following groups: parents or guardians of children 2 years of age and younger who have TB infection, and children 4 years of age and younger with TB disease or chest x-ray findings consistent with TB-related abnormalities. Guidelines for interviews for source case investigations are covered in Module 4.
5Deciding When to Investigate Confirmed cases of infectious form of TB (e.g., pulmonary or laryngeal)Suspected TB cases, before confirmationSuspected TB cases with negative sputum smearsCase has positive chest x-ray (CXR)Suspected TB cases with negative sputum smears, identified during outbreak investigationContact Investigation GENERALLY not required when:-Noninfectious forms of TB disease-Cases younger than 10 years of age (Source Case Investigation)-*Defer to local policy when making determination to investigate
6When to Investigate (cont.) Highest Priority:Highly infectiousSymptomaticSettings conducive to transmissionHigh risk for rapid development of TB diseaseWeakened immune systemsChildren younger than 5 years oldCritical considerations:- Resources- Concurrent high-priority taskingsInvestigation of contacts with minimal findings to support TB diagnosis is not recommended.
7CDC Contact Investigation Algorithm Source: CDC Investigations of Contact of Persons with Infectious Tuberculosis, 2005
8Data Collection (Pre-Interview Phase) Purpose:Focuses investigation effortAssists in development of Interview PlanPre-interview Information Sources:Medical RecordReporting providerPublic health records (previous identification of case)Tuberculosis Genotyping Information Management System (TB GIMS)
9Infectious Period Determination (Pre-Interview Period) Patient Information:Disease characteristics/siteOnset of illness/symptomsNames of ContactsExposure locations and recent travelDate of treatment initiation/Rx susceptibilityLab/Genotype resultsDemographics (including preferred language)Concurrent medical conditions (e.g., HIV)Potential communication barriersEstimation of infectious periodSputum Smear Positive Cases: 3 months before diagnosis or symptom developmentSymptomatic Sputum Smear Negative Cases: 3 Months “”Non-Symptomatic, Negative Smear Cases: 1 Month “”
10Estimating the Beginning of the Infectious Period Characteristic of Index CaseTB symptomsAFB sputum smear positiveCavitary chest radiographLikely period of infectiousnessYesNo3 months before symptom onset or 1st positive finding consistent with TB disease, whichever is longer4 weeks before date of suspected diagnosis3 months before positive finding consistent with TBSOURCE: California Department of Health Services Tuberculosis Control Branch; California Tuberculosis Controllers Association. Contact Investigation Guidelines. Berkley, CA: California Department of Health Services; 1998.
11Infectious Period & Prioritization (Pre-Interview Period) Criteria for determining the end of the infectious period:Effective Treatment for 2 weeks or moreSymptom improvementBacteriologic Response (3 negative AFB results)Exposure to contacts has endedAssigning Priorities to ContactsExposureAge/Immune StatusFactors/Degree of Infectiousness
12Prioritization of Contacts (AFB Culture Positive) Source: CDC Investigations of Contact of Persons with Infectious Tuberculosis, 2005
13Prioritization (AFB Culture Negative) Source: CDC Investigations of Contact of Persons with Infectious Tuberculosis, 2005
14Factors Associated with Infectiousness Source: CDC Investigations of Contact of Persons with Infectious Tuberculosis, 2005
15Factors for Infectiousness (cont.) Source: CDC Investigations of Contact of Persons with Infectious Tuberculosis, 2005
16Interview Timelines Index (Source) Case First Interview should be conducted within ONE day of reportingConduct in personConsider contact/safety precautionsTB Clinic/HospitalPatient’s HomeMinimum of TWO interviews (1-2 weeks apart)Contact CasesFirst Interview should be conducted within THREE days of identificationHighest Priority firstSite VisitsComplete within THREE days of initial case interviewAllows for verification of findingsOn average, 10 contacts are listed for each person with a case of infectious TB in the United States (50,59,89). Approximately 20%--30% of all contacts have LTBI, and 1% have TB disease (50). Of those contacts who ultimately will have TB disease, approximately half acquire disease in the first year after exposure (90,91). For this reason, contact investigations constitute a crucial prevention strategy
17Interview Strategies Goals are identification of: WHERE infectious period was spentWHAT activities/events case was involved inWHO case spent time with during infectious periodConsiderationsComplete Pre-Interview Activities FIRSTDetermine interview locationConsider mental and physical condition of intervieweeProxy InterviewsAnticipate and prepare for resistanceVerify & ClarifyReinforce treatment instructions and risk mitigation strategiesAllow time for questionsEnsure confidentialityEducate
18Initial InterviewsAllows for initial collection of data related to contacts/exposure locationsPermits face-to-face assessmentAfter initial information collectedPriority assignments should be reassessedMedical plan for diagnostic tests and treatment determined for contacts (e.g. Army TB Policy, 2013)Plan for follow-up Interview (highly recommended)Facilitates RecallAllows for reassessmentPrevious M. tuberculosis infection or disease and related treatmentContact’s verbal report and documentation of previous TST resultsCurrent symptoms of TB illnessMedical conditions making TB disease more likelyMental health disordersType, duration, and intensity of TB exposureSociodemographic factorsHIV status; contacts should be offered HIV counseling and testing if status unknownInformation regarding social, emotional, and practical matters that might hinder participation
20Developing a Plan for Investigation General purpose of Investigation plan:Refine estimatesPrioritize contactsSymptomatic = Top PriorityLikelihood of transmissionRisk for TB disease developmentPrioritize identified places to conduct field visitsAlso consider…Development of communication plan for staffClarification of jurisdictional issuesMethods of investigation, assessment (TST/IGRA)Identification of stakeholdersPotential media interestSchedule to review progress/barriersElaborate on location based assessments – help in identifying contact that have not yet been identifiedAdditional consideration includes - safety
21Notes regarding TST/IGRA Testing Consider the following CDC guidelines:Do NOT retest previous positivesAssess for symptoms, previous treatmentsContacts found to have positive TST/IGRAs should be considered positive for LTBI (>5mm TST Reading = POSITIVE)Repeat testing for initial negatives8-10 Weeks after exposure to caseConsider Window PeriodTime between contacts last exposure to case and when TST/IGRA can reliably detect infection2 to 8 weeks needed for body to mount detectable response to infection
22Expanding the Investigation Conditions for Expansion:Achievement of program objectives/plan executionUnexpectedly large rate of infection or TB diseaseTB disease in any contacts who had been assigned low priorityInfection in any contacts aged <5 yearsContacts with change in TST/IGRA status from negative to positiveHigher than expected prevalence of TB infectionCalculation of TB Infection Prevalence for contactsEvidence of secondary transmissionLocal policy
23Additional Considerations Investigations of:Social and RecreationalHospitalsWorkplace/School SettingsSite SpecificNumber involvedExposure Duration and ProximityResources
24Data Management Management and epidemiologic analysis Program evaluation using performance indicatorsProcess steps necessary for monitoring timeline objectivesAssessment/reassessment of investigation strategyNumber of index patients investigated for their sourcesNumber of associates screened for TB diseaseNumber of times a source is found
25Communication Considerations Appropriate language levelCultural Awareness/SensitivityIdentification and mitigation of communication barriersOpen-ended questionsRestate/SummarizeDemeanorNon-Verbal Communication
26Confidentiality Essential to maintaining credibility and trust Constant attention required to maintain confidentialitySpecific policies for release of confidential information related to contact investigations are recommendedInformed ConsentPolicies & Training
27Concluding a Contact Investigation Contact Investigation can be concluded if:Identified contacts have been assessedContacts with LTBI have completed or are close to completing treatmentNo additional secondary cases of TB among identified contacts are foundFollow local policyNext steps:Begin ‘after action review’How many contacts identified/treated?How many contacts located, follow ups completed?Appropriate expansion?Training/resource needs? Effectiveness?Follow up plan?
28Additional Training Essential for successful contact investigations Consider collaboration with local health care agenciesTraining Resources:TB101 for Healthcare WorkersTools from CDC
29ReferenceContent adapted from: 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)