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Copyright © 2020 American College of Occupational and Environmental Medicine. Unauthorized reproduction of this article is prohibited

Tuberculosis Screening, Testing, and Treatmentof US Health Care Personnel

ACOEM and NTCA Joint Task Force on Implementation of the2019 MMWR Recommendations

Wendy Thanassi, MD, MA, Amy J. Behrman, MD, Randall Reves, MD, Mark Russi, MD, MPH,

Melanie Swift, MD, MPH, Jon Warkentin, MD, MPH, Ryo Miyakawa, MD, Donna Wegener, MA,

Lawrence Budnick, MD, MPH, Ellen Murray, RN, PhD, Ann Scarpita, BSN, MPH,

Bobbi Jo Hurst, MBA, Sarah Foster-Chang, DNP, ANP-BC, Trini Mathew, MD, MPH,

MaryAnn Gruden, MSN, COHN-S/CM, Julie Higashi, MD, PhD, and Thomas Warner Hudson III, MD

On May 17, 2019, the US Centers for Disease

Control and Prevention and National Tuberculosis

Controllers Association issued new Recommenda-

tions for Tuberculosis Screening, Testing, and Treat-

ment of Health Care Personnel, United States, 2019,

updating the health care personnel-related sections

of the Guidelines for Preventing the Transmission of

Mycobacterium tuberculosis in Health-Care Set-

tings, 2005. This companion document offers the

collective effort and experience of occupational

health, infectious disease, and public health experts

from major academic and public health institutions

across the United States and expands on each

section of the 2019 recommendations to provide

clarifications, explanations, and considerations that

go beyond the 2019 recommendations to answer

questions that may arise and to offer strategies for

implementation.

T he American College of Occupationaland Environmental Medicine

(ACOEM) fully supports implementationof the Unites States’s (US) Centers for Dis-ease Control and Prevention (CDC) andNational Tuberculosis Controllers Associa-tion’s (NTCA) Recommendations for Tuber-culosis Screening, Testing and Treatment ofHealth Care Personnel, United States, 2019.1

The new guidance updates the health carepersonnel-related sections of the Guidelinesfor Preventing the Transmission of Mycobac-terium tuberculosis in Health-Care Settings,2005.2 In particular, both ACOEM andNTCA endorse the discontinuation of routine

annualtuberculosis(TB)testinginhealthcarepersonnel (HCP) and the increased emphasison the role of occupational health in encour-aging treatment of persons with latenttuberculosis infection (LTBI) to prevent pro-gressiontoactivedisease (reactivation)andtopositively impact the public’s health.

This document offers the collectiveeffort and experience of occupational health,infectious disease, and public health expertsfrom major academic and public health insti-tutions across the US. It expands on eachsection of the 2019 Mortality and MorbidityWeekly Report (MMWR) CDC/NTCA Rec-ommendations to provide clarifications,explanations, and considerations that gobeyond the 2019 MMWR CDC/NTCA rec-ommendations to answer questions that mayarise and to offer strategies for implementa-tion. This ‘‘companion’’ document was writ-ten to support the nation’s occupationalhealth providers, infection preventionists,public health officers, valued HCP, and thepatients we serve.

The sections to follow closely mirrorthose of the 2019 MMWR CDC/NTCARecommendations:

IntroductionBackground with Literature ReviewBaseline (post-offer/pre-placement)Screening and Testing� Post-Offer/Pre-Placement (POPP) TB

Risk Assessment and SymptomReview

� TB Testing for HCP Without PriorPositive Test

� Regarding Reversions� TB Testing for HCP with Prior

Positive Test� Newly Confirmed Positive TB Test

and/or Positive Symptom Review� Considering Active TB Disease� Compliance, Confidentiality, and

CommunicationPost-exposure TB Screening and Testing� Overview� Travel-Related Exposure

� Voluntary Testing for Self-assessedPotential Exposure

� Post-Exposure Testing Consider-ations and Interpretation

Serial Screening, Testing and Educationfor HCP� Serial Screening and Testing� Annual Education Requirement� Annual Symptom Review for HCP

with LTBI� Transitioning a TB Screening Pro-

gram for Health Care PersonnelTreatment and Education of Health CarePersonnel with Positive Test Results� Progression from LTBI to TB Dis-

ease (Reactivation TB)� Educating HCP with LTBI� Recommending Treatment

The 2019 MMWR CDC/NTCA rec-ommendations shift the focus from routineserial testing to improving education andincreasing LTBI treatment. Identifying, tothe best of our ability, the presence of LTBIallows occupational health practitioners toencourage treatment and prevent future TBdisease. Efforts to eliminate LTBI supportworkforce and workplace health locally,while moving us closer to a TB-free nation.

KEY POINTS – 2019 MMWRCDC/NTCA Recommendations

� The term health care worker has beenreplaced by HCP and refers to all paid andunpaid, part time, temporary, contract,student and full-time persons working inhealth care settings.

� At the point of hire or transfer into a clinicalposition, all HCP should have baseline TBscreening that includes an individual riskassessment, symptom evaluation and (forthose without LTBI or TB disease) a test forM. tuberculosis infection.

� Treatment to prevent progression to activeTB disease (reactivation TB) is stronglyencouraged for all HCP diagnosed withLTBI.

� HCP without LTBI should not undergoroutine serial TB screening or testing atany interval after baseline (eg, annually)

From the American College of Occupational andEnvironmental Medicine, Elk Grove, Illinois.

The authors declare no conflicts of interest.Supplemental digital contents are available for this

article. Direct URL citation appears in theprinted text and is provided in the HTML andPDF versions of this article on the journal’s Website (www.joem.org).

Address correspondence to: Marianne Dreger, MA,ACOEM, 25 Northwest Point Blvd, Suite 700,Elk Grove Village, IL 60007 ([email protected]).

Copyright � 2020 American College of Occupa-tional and Environmental Medicine

DOI: 10.1097/JOM.0000000000001904

JOEM � Volume 62, Number 7, July 2020 e355

ACOEM GUIDANCE STATEMENT

http://www.joem.org/

mailto:[email protected]


in the absence of known exposure orevidence of ongoing TB transmission.

� HCP with untreated LTBI should receive ayearly symptom review, TB education,and treatment encouragement.

� The facility risk assessment, contained inthe 2005 MMWR CDC GuidelinesAppendix B,2 continues to be requiredannually for the assessment andmaintenance of environmental controls(Appendix 1, http://links.lww.com/JOM/A780).

� After known exposure to potentiallyinfectious TB without adequate personalprotection, HCP should have a symptomevaluation and timely TB testing.

� All HCP should receive TB educationannually. Education should includeinformation on TB risk factors, the signsand symptoms of TB disease, TB infectioncontrol policies and procedures, and LTBItreatment regimen options.

BACKGROUND WITHLITERATURE REVIEW

In the 1920s, US researchers beganto recognize that HCP were at risk of con-tracting TB from patients.3 By the 1950s,TB rates remained as high as 50 cases per100,000 population and the increased riskof nosocomial TB in health care occupa-tions became more clear.3,4 Routine admis-sion chest x-rays (CXR) were instituted andwere shown to reduce TB risk among HCP.4

By the 1980s, when TB rates decreased by80% to under 10 cases per 100,000 popula-tion, the utility of such routine admissionradiography was questioned.5 There wereoccasional published reports of nosocomialtransmission of TB to HCP from the 1960sand 1980s, usually attributed to diagnosticand/or treatment delays in environmentswith inadequate ventilation.3

The TB resurgence of 1985 to 1992,which mirrored the rise of human immuno-deficiency virus (HIV) in the US, resultedin a concurrent rise in nosocomial TBtransmission to HCP in urban hospitalsand again highlighted their occupationalrisk. US TB rates increased from 9.3 to10.4 per 100,000. Numerous investigations

attributed facility-based transmission toadministrative errors (inadequate infectioncontrol policies), clinical errors (missedand delayed diagnoses and delayed drug-resistance detection), and poor engineeringcontrols (inadequate ventilation).3,6,7 HCPtuberculin skin test (TST) conversions inthe early 1990s ranged from less than 0.1%to 4.5% annually in hospitals in non-out-break settings, but were as high as 20% injust 6 months in some institutions withoutbreaks.8 Annual TST conversions inhospitals with high TB admission rateswere over 4% in the early 1990s butdropped to less than 1% within years ofadopting improved administrative and engi-neering controls.6–9

Publications in this decade confirmannual US HCP TST conversion rates wellbelow 1%. At a Midwest tertiary care med-ical center, 39,280 HCP with a baselinenegative TB test underwent nearly200,000 annual TSTs and only 123(0.31%) conversions were detected over a16-year period.10 Most of the TST conver-sions appear to have been false-positiveTSTs attributed to a delayed boosting effectsince the positive TSTs occurred most fre-quently with the third TST placed duringemployment. In addition, only 9% of the123 conversions were associated withknown workplace or community TB expo-sure, 66% of these had negative interferongamma release assay (IGRA) results, andno one developed active TB disease. Thesedata, along with annual conversion rates ofless than 1% in HCP at medical centers thatcare for patients with active TB disease,illustrate that the efficacy of TB infectioncontrol programs resulted in limiting theTB transmission to HCP.6,9

In a remarkable turn of events, effec-tive TB infection control has led to such alow probability of HCP exposure that theTB rate in US HCP has dropped below thatof the overall population. Two nationalstudies published by CDC compared withTB rates among HCP to the total US popu-lation, one for the 5-year period 2003 to

200711 and the second for the 7-year period2010 to 2016.12 Both showed consistentevidence of lower TB incidence ratesamong HCP compared with the nationalpopulation. The mean annual HCP TB ratesfor the 5-year period 2003 to 2007 and the7-year period 2010 to 2016 were 4.2 and 2.5per 100,000 persons, respectively. Duringthese study periods, the US annual TB ratesdeclined from 5.1 to 4.4, and from 3.6 to2.9, respectively (Table 1). In addition toTB rate comparisons, the national genotyp-ing data estimate the proportion of TB casesdue to recent transmission was only 10% inHCP, compared with 14% in the populationoverall.12

The epidemiology of TB amongHCP parallels the national pattern of pre-dominately occurring in non-US-born per-sons.11 Lambert et al11 also described thefeatures of TB disease over the 13-yearperiod of 1995 to 2007 that included fataloutcomes among 3.1% of HCP reported TBcases, while fatal outcomes nationally were10.9%. The relatively lower incidence andmortality rate from TB disease in the HCPpopulation is not unexpected consideringHCP are generally well-educated,employed, tend to have adequate housingand nutrition, and are in the middle of theage spectrum. These studies provide furtherevidence of very limited nosocomial orconsequential transmission of TB toUS HCP.

In this era of low TB incidenceamong US HCP, the high cost of maintain-ing annual testing and the burden of false-positive results has led to several revisionsof recommendations for LTBI testing. The2017 Clinical Practice Guidelines by Con-sensus of the American Thoracic Society,Infectious Diseases Society of America,and the CDC recommend the use of IGRAsover TSTs in low-risk persons who undergomandatory testing.14 IGRAs require only asingle encounter, have higher specificitythan the TST among individuals with priorbacille Calmette-Guerin (BCG) vaccina-tion,15,16 and are reported in many studies

TABLE 1. Mean Annual Numbers and Rates of Active TB Cases among Health Care Personnel (HCP) by Country of Birthduring 2003–2007 and 2010–2016, Compared With the Total US Annual Numbers and Rates for 2005 and 2013

HCP� USy

Study Period US-born Non-US-born HCP Total US-born Non-US-born US Total

2003–2007 Rate 1.7 17.9 4.2 2.5 22.3 4.8No. (%) 151 (35) 278 (65) 429 (100) 6,290 (45) 7,745 (55) 14,065 (100)

2010–2016 Rate 0.8 10.8 2.5 1.2 15.7 3.0No. (%) 90 (28) 262 (72) 352 (100) 3,330 (34) 6,222 (68) 9,561 (100)

�The mean annual numbers and rates for the 5- or 7-year periods were obtained from Lambert et al,11 Mongkolrattanothai et al,12 and via Lauren Lambert, personalcommunication.

yThe comparison annual US numbers and rates for the two study periods are the data of 2005 and 2013, the mid-year of each study period when rates declined from 4.4 to 5.1 and3.6 to 2.9, respectively.13

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e356 � 2020 American College of Occupational and Environmental Medicine

http://links.lww.com/JOM/A780



to be more cost-effective than TST forserial screening.11,17–19 However, the spe-cificities of both approved IGRAs appearlower than with TST when used for serialtesting of low risk populations who did nothave BCG vaccination.

A multicenter study comparing theperformance of serial TST and of both ofthe IGRAs then approved by the US Foodand Drug Administration (FDA) was con-ducted from 2008 to 2011 among HCP atfour US hospitals with annual TST conver-sion rates of less than 1%. In this study,simultaneous TST, QuantiFERON1-TB-Gold In Tube (QFT-GIT) (QFT, QiagenInc.), and T-Spot1.TB (TSPOT, OxfordImmunotec) were obtained at baselineand repeated thrice at 6-month intervals.Among over 2100 HCP with baseline neg-ative tests, the cumulative number of con-versions was 21 (0.9%) for TST as expectedbut was 138 (6.1%) with QFT-GIT, and 177(8.3%) using the T-Spot1.TB. There wereno known TB exposures at the institutions.Only four HCP converted by both TST plusone IGRA, and 17 converted by TST alone.Repeat tests found reversion to negative in65% of the TST converters and over 75%for converters with either IGRA, demon-strating the low positive predictive value ofTB tests in US HCP.20 These findings havebeen supported in other studies including a2018 report of a retrospective cohort anal-ysis of 40,142 tertiary care HCP whoreceived a TST, showing 123 conversionsover 16.4 years. Only nine (7%) of theconverters had a suspected workplace TBexposure and none developed active TB.The majority (66%) of TST converters hada negative QuantiFERON-TB test result atthe time of the TST conversion.21

In addition to reducing serial TB test-ing, the 2019 MMWR CDC/NTCA Recom-mendations emphasize the need to increaseefforts to encourage treatment of LTBI,whether it was acquired in the communityor in the workplace.22 The emphasis on LTBIdiagnosis, education, and treatment comple-tion is an attempt to prevent reactivation andthereby reduce TB morbidity, mortality, andtransmission to other HCP and patients.

BASELINE (POST-OFFER/PRE-PLACEMENT) SCREENING

AND TESTING

2019 MMWR CDC/NTCA Recommen-dation: ‘‘All US health care personnelshould have baseline TB screening,including an individual risk assessment,which is necessary for interpreting anytest result. The 2005 guidelines state thatbaseline test results provide a basis forcomparison in the event of a potential orknown exposure to M. tuberculosis, facilitatedetection and treatment of LTBI or TBdisease in health care personnel before

placement, and reduce the risk to patientsand other health care personnel. The riskassessment and symptom evaluation helpguide decisions when interpreting testresults. For example, health carepersonnel with a positive test who areasymptomatic, unlikely to be infectedwith M. tuberculosis, and at low risk forprogression on the basis of their riskassessment should have a second test(either an IGRA or TST) as recommendedin the 2017 TB diagnostic guidelines of theAmerican Thoracic Society, InfectiousDiseases Society of America, and CDC. Inthis example, the health care personnelshould be considered infected with M.tuberculosis only if both the first andsecond tests are positive.’’1

SummaryThe primary changes from the 2005

MMWR CDC Guidelines specific to thepost-offer pre-placement process are theaddition of an individual TB risk assess-ment with symptom review, and the recom-mendation to strongly encourage treatmentof HCP with LTBI.2

Post-Offer/Pre-Placement(POPP) TB Risk Assessment andSymptom Review

The 2019 MMWR CDC/NTCA Rec-ommendation states that all HCP shouldhave a baseline POPP TB evaluation. Anupdated list of employees who are desig-nated as ‘‘HCP’’ is included in Appendix 2,http://links.lww.com/JOM/A781.2 Forinstitutions where non-clinical new hiresare not screened for TB, those employeesshould enter the pre-placement TB screen-ing process if they transfer into a clinicalposition.

POPP TB screening is done in orderto: (a) rule out active TB disease prior toplacement; (b) identify LTBI and offer treat-ment or consultation for treatment as appro-priate; and (c) establish a baseline to guideinterpretation of future tests in the event of anew exposure or new symptoms suggestingactive TB disease. POPP TB screening willalways include a risk assessment, TB history,and a symptom review; will usually includetesting by IGRA or TST; and may includeimaging or additional evaluation to rule outactive TB disease and guide treatment rec-ommendations.

Individual risk assessments are nec-essary for interpreting test results. Theseshould include:

� Risk factors for exposure, such as knownexposure to person(s) with active TBdisease or birth/residence in TB endemiccountries (see 2019 MMWR CDC/NTCA Recommendations Risk Assess-ment1).

� Risk factors for progression to active TBdisease (reactivation TB), such asimmune-suppressing medications, diabe-tes, cancer, organ transplant, or HIV.23

Note that diabetes is not a risk factor foracquiring TB, but having diabetes impartsa 2 to 4-fold increased risk for LTBIprogressing to active TB disease.24

Additionally, obtaining the individu-al’s TB history is important and couldinclude:

� Documentation of prior TB test results(including dates and type of test wherepossible),

� History of LTBI or active TB disease,and

� Treatment history for active TB diseaseor for LTBI including location of treat-ment, length of treatment, medicationstaken (if known), whether treatment wascompleted, and any current symptomsconsistent with active TB disease.

The symptom review should include:

� Questions regarding the presence of pro-longed (more than 3 weeks), unex-plained fever, prolonged cough orfatigue, hemoptysis, unintended weightloss, or drenching night sweats.

The individual risk assessments,including the TB history and symptom reviewquestions (screening questionnaire), can beadministered electronically, on paper, or byinterview but should be standardized withinan institution. Screening questionnairesshould be consistent with national guidelines,evolving best practices, state/local healthdepartment requirements, and institutionalpolicies. Since the HCP responses willinclude both health information and otherprotected personal information, completedTB screening questionnaires must be keptconfidential. A licensed practitioner or quali-fied occupational health professional shouldreview screening questionnaires and docu-mentation of treatment. Clinical practices/institutions may opt for a single integratedscreening questionnaire to streamline theonboarding process, or may use the riskassessment form included with the 2019MMWR CDC/NTCA Recommendations,1

in combination with a TB history and symp-tom review. A sample integrated question-naire addressing all essential components ofTB screening is appendedand may be adaptedto meet institutional needs (Appendix 3,http://links.lww.com/JOM/A782).

TB Testing for HCP WithoutPrior Positive Tests

Institutions may opt to accept recent,documented negative TB test results fromother employers or training programs. The

JOEM � Volume 62, Number 7, July 2020 Tuberculosis Screening, Testing, and Treatment of US Health Care Personnel

� 2020 American College of Occupational and Environmental Medicine e357




decision to accept such results will varybased on reliability and remoteness of thereport, workers’ compensation consider-ations and facility policy. Institutions thataccept prior negative IGRA or TST resultsfor POPP clearance should use a consistentapproach considering time interval, expo-sure risk, and medical history.

The initial TB test for HCP without adocumented prior positive TB test can beeither an IGRA (preferred) or a TST.14 Thechoice of test may be influenced by a healthcare institution’s specific cost, staffing, andlogistical considerations. A single test typeshould be employed as much as possible inorder to maintain consistency in interpreta-tion. Current FDA-approved whole bloodIGRA tests are the QuantiFERON1-TBGold Plus (QFT, Qiagen Inc.),25 anenzyme-linked immunoassay (ELISA),and the TSPOT1.TB (TSPOT, OxfordImmunotec),26 a ficoll-separation assay(ELISPOT). Both tests utilize negativeand positive controls, and both use theMTB-specific antigens ESAT-6 and CFP-10. Both assays are indirect measures ofinterferon gamma release in response tothe TB-specific antigens. IGRAs haveadvantages over the TST during the onboard-ing process, including greater specificity inthe BCG vaccinated and faster time-to-onboarding compared with the two-stepTST.27,28 Retesting indeterminate orinvalid (QFT) and borderline or invalid(TSPOT1.TB) results is recommended.The intradermal TST utilizes purified pro-tein derivative (PPD) tuberculin antigensolution and is sold in the US under the tradenames Tubersol1 (Sanofi Pasteur Ltd.,Toronto, Canada) and Aplisol1 (JHP Phar-maceuticals, LLC, Rochester, MI).

Intradermal TST placement andreading require annual training and compe-tency. All tests should be placed consistentwith CDC methodology and standards.Standardized training using validatedresources is available (eg, CDC TST train-ing video29). Institutions using TSTs toscreen newly hired HCP should use thetwo-step methodology, with retesting ide-ally 1 to 3 weeks after the first TST.2 Two-step TST is a recognized way of boosting animmune response that may have wanedafter a prior infection. HCP with a poorlydocumented prior positive TST may alsobenefit from two-step TST to confirm priorinfection. A consistent approach for accept-ing documentation of prior TST results foreither ‘‘step’’ should be adopted (recogniz-ing that the evidence basis for cut-offs islimited). For instance, a policy might stip-ulate that a documented TST within a yearprior to onboarding is acceptable.2 Thetwo-step TST process is recommendedfor clearance when more than 1 year haselapsed since the most recent TST.2

Test results should be interpreted inthe context of the individual’s TB riskassessment and current guidelines.1,14 Usu-ally, a single negative IGRA or a negativetwo-step TST is sufficient for TB clearanceof HCP without TB risk factors. A positiveTST is defined by the combination of indu-ration and risk factors. For instance, a TSTis considered positive at more than or equalto 5 mm for any person with either immu-nocompromising conditions (such as HIVinfection) or with known, recent, unpro-tected TB exposure. The TST is consideredpositive with induration more than or equalto 10 mm for HCP without immunocom-promising conditions and without a known,recent, unprotected TB exposure.30 Finally,more than or equal to 15 mm induration isthe positive ‘‘cut-off’’ for individuals (non-HCP) without immunosuppression or iden-tified TB exposure. Note that CDC’s posi-tive cut-off induration for HCP, despite lowrates of TB in HCP and data showing thatmost HCP do not have elevated risk com-pared with the general population, currentlyremains at more than or equal to 10 mm.2

Newly positive IGRA or TST resultsin HCP who have been negative in the pastand are without risk factors for exposure toTB (ie, those with a low probability of trueinfection) should have a confirmatory/repeat TB test prior to radiography. If therepeat test is negative the result can, in theabsence of clinical symptoms of TB, beregarded as negative and accepted foremployment placement without radio-graphs.14,16 When the repeat test is difficultto obtain, or when a significant delay mayoccur, a negative chest radiograph can beused for hiring clearance with the repeat testplaced or drawn at the same time.

Regarding ReversionsThe recommendation to repeat posi-

tive tests for confirmation in HCP withoutknown exposure to active TB has been aCDC recommendation since 2010 and hasbeen supported by extensive literature onserial testing of US HCP.14,16,31–35 Thisrecommendation has both operational andmathematical premises.

First, TST and both IGRAs are indi-rect measures of infection based on a skininduration or whole blood interferongamma response to TB-specific antigens:they are not direct visualizations of themycobacteria. Second, both IGRAs havecut-off values that were assigned by theFDA to maximize specificity, so that thelikelihood of a false-negative result is min-imized. On a scale of 0 to 10 internationalunits per milliliter (IU/mL), the QFT isconsidered negative at less than 0.35 IU/mL, corresponding to 99% specificity.25,36

Subsequent research, some of it summa-rized in a meta-analysis, has shown the QFT

specificity to be closer to 95%, while thatof the TST is roughly 97% in thosewith no prior exposure to BCG.15 TSTspecificity is reduced to closer to 60% inthose with a history of BCG vaccina-tion.15 For TSPOT, a negative result isreturned when the number of spotscounted (range 0 to 100s) is 0 to 4 inthe US and 0 to 6 in Europe, equating to a95% to 97% specificity.14,26

Mathematically, when highly specifictests for low-prevalence diseases are used inlarge populations that are at low-risk for thedisease, false-positive rates rise due to math-ematical principles of positive and negativepredictive values. (PPV¼True positives/(true positives þ false positives)� 100.NPV¼True negatives/(true negativesþfalse negatives)� 100). Therefore, positiveresults in this setting represent an indirectmeasurement of interferon-gamma releasethat may be just above the FDA-mandatedcut-off point, but actually reflect only a mini-mally higher likelihood that the infection ispresent. Further, when tests in large popula-tions are repeated, a repeated result will tendto more accurately represent the mean resultof the entire population (known as regressionto the mean), which in the case of US HCPand TB, is a negative result.37 Therefore,repeating an unexpected test result in a popu-lation that has an overall low prevalence of thedisease may yield a more accurate result thanthe original test provided.

TB Testing for HCP with PriorPositive TB Tests

Documentation should be obtainedwhenever possible for previous TB testresults, imaging and TB treatment includ-ing compliance. For those with LTBI thatwas untreated or partially treated, furthertesting may be indicated. HCP with a pre-viously positive TB test who have notcompleted treatment, or who report relevantsymptoms regardless of treatment history,should undergo a focused physical exami-nation to identify signs of TB diseaseincluding examination of the lungs and bothcervical and supraclavicular lymph nodes.

Obtaining a new TB test in individ-uals with previously positive test resultscould be considered when additional testresults are likely to alter management. Keyexamples include:

1. HCP with prior positive TSTs who havepreviously declined LTBI treatment mayaccept chemoprophylaxis to reduce therisk of progression to active TB diseasewhen presented with confirmatory IGRAresult.38–42

2. HCP who have received BCG vaccina-tion and have a prior positive TST maybenefit from the increased specificity ofthe IGRA.




3. HCP with an undocumented prior posi-tive TST may benefit from a two-stepTST to confirm prior infection. TST isconsidered safe in HCP with a history ofpositive TST results, except when aprior TST was associated with necrosis,blistering, ulceration, or anaphylaxis.43

4. HCP with low positive or unquantifiedresults by an older generation IGRA andno history of TB treatment may benefitfrom retesting with a newer generationIGRA to clarify treatment recommenda-tions.

5. HCPwith IGRAresults thatarediscordantor suggest reversion may benefit from aTST. TSTs should be avoided in HCP witha history of necrotic, blistering, ulcerated,or anaphylactic reactions to TST.43

Asymptomatic HCP with docu-mented prior positive TB tests (IGRAand/or TST) do not require imaging forclearance if they have documentation ofnormal chest imaging after the prior posi-tive TB test. A normal CXR is one with noradiographic evidence of TB disease orgranuloma. Repeat imaging in the contextof a normal baseline CXR is not recom-mended by the CDC but may be required bylocal workers’ compensation or facilityguidelines. If repeat imaging in this contextis conducted, the facility should be consis-tent in the documentation and time framerequirements for prior CXR.

Re-imaging during the POPP TBevaluation can also be considered in HCPwith a prior positive TB test and a priornormal CXR based upon review of their TBrisk assessments:

1. When there has been known exposure toactive TB since the prior image wasobtained or extended time spent inregions with elevated TB rates,

2. When prior imaging is not well docu-mented or is not normal,

3. When previous LTBI treatment wasincomplete,

4. When the HCP was not treated for LTBIand has risk factors for progression toactive TB disease (reactivation TB).

Newly Confirmed Positive TBTest and/or Positive SymptomReview

For low-risk HCP (defined as those‘‘who are asymptomatic, unlikely to beinfected with M. tuberculosis, and at lowrisk for progression on the basis of their riskassessment,’’)1 a confirmed positive TB testis a test that is positive and when repeated ispositive again. HCP with a history ofnecrotic, blistering, ulcerated, or anaphy-lactic reactions to TST, if retested, shouldbe tested with an IGRA.43 All HCP withconfirmed positive TB tests should be

counseled by a qualified provider regardingfurther evaluation and management. Amajor tenet of the 2019 MMWR CDC/NTCA Recommendations is that theonboarding process provides a crucialopportunity to offer counseling and tostrongly encourage treatment for LTBI(see section on ‘‘Education and Treatmentof Health Care Personnel with Positive TestResults’’ for further information).

The medical history, previous TBtest results, identified TB exposures, andany prior TB or LTBI treatment should beevaluated to ascertain whether a positivetest represents a new conversion or reflectsa remote exposure. A history of time spentin any TB endemic country may also berelevant to establishing an infection time-line. A thorough work and volunteer historycan also establish possible exposures. Thistimeline is important because active TBdisease is most common in the first 2 yearsfollowing exposure with conversion.44

The medical history should alsoelicit factors that would predispose thepatient to progress to active TB diseasesuch as HIV/AIDS, immune suppression(eg, cancer, solid organ transplant, biologicmedications), recent significant weightloss, diabetes, smoking, or fibrotic lungdisease. CDC recommends screening adultswith LTBI for HIV in health care settings,45

and the US Preventive Services Task Forcerecommends screening adults for diabe-tes.46 Given the high risk of progressionto active TB disease in patients withuntreated comorbidities, this TB evaluationpresents a logical opportunity to recom-mend diabetes and HIV screening if notpreviously done. Symptoms of pulmonaryor extra-pulmonary TB should alsobe ascertained.

The physical examination shouldidentify signs of active TB disease andinclude auscultation of the lungs, and pal-pation of both cervical and supraclavicularlymph nodes. Weighing the patient is usefulto document weight stability, loss or gain.

All HCP with newly confirmed pos-itive TB tests should be evaluated with aCXR. CXRs are reasonably sensitive foractive pulmonary TB, and the vast majorityof asymptomatic HCP with newly positiveTB tests can be cleared safely for workplacement based on a normal CXR alone.A single posterior-anterior (PA) view isusually adequate for employment clearancein asymptomatic individuals without TBrisk factors.

Considering Active TB DiseaseActive pulmonary tuberculosis is a

serious, contagious disease: between 5%and 10% of people will die before or duringtheir treatment for TB disease.47 Active TBdisease poses a disproportionately high risk

of mortality to the elderly, young andimmune compromised. Most states requireprompt public health reporting of personswith suspected active TB disease, and con-firmed active TB is reportable to the localhealth department in all states. Public healthdepartments are responsible for contactscreening in the community, for monitoringtreatment of individuals with confirmedactive TB disease, and for providing clear-ance for the treated employee to return towork. State and local public health depart-ments can also offer valuable insights andresources for TB screening, diagnosis, andtreatment in circumstances when guidancefrom this companion document cannot bedirectly applied due to unique characteristicsof the HCP, local regulations, or limitedavailable occupational health resources.

If imaging or clinical presentationsuggests active pulmonary TB disease, fur-ther evaluation is necessary for work clear-ance. For HCP with possible infectiousTB, occupational health clinicians shouldarrange for appropriate isolation precautionswhen necessary. Of note, neither the TST,IGRA, clinical examination, nor imagingalone can exclude active TB disease.False-negative IGRAs and TSTs occur in10% to 30% of people with active TB diseaseand are more frequent among those withextra-pulmonary TB and those with immunesuppression. Clinicians should not rely onthese indirect tests for M. tuberculosis infec-tion when active TB is suspected.48

Chest radiography is a mainstay ofthe initial evaluation for possible activepulmonary TB disease. While a singlePA view is usually sufficient, adding alateral view may improve sensitivity, par-ticularly in immune compromised HCPwho are more likely to have atypical radio-graphic presentations of active TB.49,50

Additional imaging, including computedtomography (CT) scanning may be indi-cated based on clinical assessment or dis-cussion with the radiologist. HCP withincidental findings of clinical significanceon CXR should be counseled, given copiesof their imaging, and confidentiallyreferred for appropriate care.

Note that CXRs are likely to benormal in HCP with extra-pulmonary TBdisease, so the absence of lung disease onCXR does not prove absence of eitheractive TB disease or of infectiousness.Oropharyngeal and laryngeal TB are highlycontagious, but not visible on CXR. Per-sonnel with suspected oropharyngeal,laryngeal, or pulmonary TB should weara mask and be restricted from work untiltheir disease is determined by experts not tobe infectious. Extra-pulmonary TB diseasein the mediastinum, bones, lymph nodes,and abdomen is also not visible onCXR, but is not contagious. HCP with these




non-contagious conditions can remain atwork during evaluation and treatment.

Clearance to work for HCP withpossible infectious TB disease requiresdirect testing for M. tuberculosis and expertconsultation. Testing may include serialsputum smear collection with acid-fastbacillus (AFB) staining, polymerase chainreaction (PCR), nucleic acid amplificationtesting (NAAT), or sputum culture. Suchtesting is sometimes completed in consul-tation with the facility’s infection control,infectious diseases, or local publichealth services.

Return-to-work clearance is appro-priate if initial smears or NAATare negativeon at least three high-quality sputum speci-mens, collected 8 to 24 hours apart with atleast one collection obtained early in themorning, even though final culture resultswill not be available for severalweeks.2,51,52 Clinical judgment shouldalways supersede test results.

Compliance, Confidentiality, andCommunication

Information management require-ments for occupational health practices thatprovide POPP TB screening and testing forHCP are complex. Minimum needs include:

� Ensuring that all newly onboarded HCPhave met institutional policy require-ments for work clearance specificallyrelated to excluding active TB diseaseand documenting LTBI,

� Ensuring that HCP with positive testresults are aware of their TB/LTBI sta-tus,

� Maintaining strict confidentiality of allmedical and personal information,

� Ensuring that HCP have been educatedon signs and symptoms of TB diseaseand are aware of when they should seekfurther medical evaluation, and

� Communicating clearance status to hir-ing managers without compromisingprotected health information. Occupa-tional health staff should restrict theirresponses to the clearance status only,without revealing further testing needs.

An overarching goal of the 2019MMWR CDC/NTCA Recommendations isto accurately identify and encourage thetreatment of LTBI in order to prevent thedevastating consequences that occur whenHCP progress to active, infectious TB dis-ease while working with vulnerable patientsand colleagues. To that end, onboardingHCP who are confirmed to have LTBI shouldbe strongly encouraged to undergo treat-ment. Occupational health staff can docu-ment treatment declination in the medicalrecord and should revisit the treatment dis-cussion and education on an annual basis.

Appendix 4, http://links.lww.com/JOM/A783 contains a sample declination form.

POST-EXPOSURE TB SCREENINGAND TESTING

2019 MMWR CDC/NTCA Recommen-dation: ‘‘After known exposure to a personwith potentially infectious TB diseasewithout adequate personal protection,health care personnel should have atimely symptom evaluation and additionaltesting, if indicated. Those withoutdocumented evidence of prior LTBI or TBdisease should have an IGRA or TSTperformed. Health care personnel withdocumented prior LTBI or TB disease donot need another test for infection afterexposure. These persons should havefurther evaluation if a concern for TBdisease exists. Those with an initialnegative test should be retested 8 to10 weeks after the last exposure,preferably by using the same test type aswas used for the prior negative test.’’1

Overview

While the US has one of the lowestincidence rates of TB in the world at 2.8cases per 100,000 persons (2018), HCPcases in the US continue to experienceexposures to persons with active pulmo-nary TB.53 A contact investigation shouldbe conducted for HCP exposed to personswith confirmed infectious TB disease oraerosolized M tuberculosis specimens.The timing and extent of contact investi-gation activities such as risk and exposureassessment, symptom screening, and test-ing should be dictated by the specificcharacteristics of the exposure. For mosthealth care settings in the US, investiga-tions may simply document the lack ofsignificant exposure due to the appro-priate engineering and administrativecontrols or use of personal protectiveequipment (PPE). The Guidelines forthe Investigation of Contacts of Personswith Infectious Tuberculosis by CDC andNTCA in 2005 contain informationregarding environmental controls, datamanagement, confidentiality, consent,and human resource considerations thatare useful when structuring and opera-tionalizing investigations.54

TB experts are also available forconsultation through jurisdictional publichealth agencies and consultation and col-laboration is encouraged. In most US juris-dictions, reporting and consultation withthe public health department is requiredupon confirmation of a case of active TBdisease in a health care setting.

Many of the principles used to deter-mine whether a significant exposure

occurred are similar to those with otherinfectious diseases, including influenzaand the pandemic novel coronavirus. Theseconsiderations include the infectiousness ofthe patient, the location and duration of theHCP relative to the infected person, theactivity being performed (eg, aerosol-gen-erating), and the environmental controlsthat are in practice (eg, PPE and ventila-tion).

The 2019 MMWR CDC/NTCA Rec-ommendations update the 2005 MMWRCDC Guidelines2 in a few important ways:

1. The definition of TB exposure is refinedby adding the language ‘‘without use ofadequate personal protection’’ to qual-ify those who should be included incontact investigations. TB transmissiongenerally requires prolonged exposurein a closed air space, but there is nostatic definition of what constitutes aTB exposure event. Table 2 lists factorsthat should be considered when gaugingthe clinical significance of an exposure.Also included in the table are factorsthat can mitigate M. tuberculosis trans-mission.

2. Contact investigations may be donewith either IGRA or TST, though thecollaborative 2017 CDC/ATS/IDSADiagnostic Guidelines recommendedIGRA over TST for exposure investiga-tions.13

3. HCP with documented prior LTBI donot need another test for infection afterexposure. This recommendation andexceptions to consider are exploredfurther below.

4. The designation of a facility as mediumrisk, based on the 2005 MMWR CDCGuidelines Facility Risk AssessmentAppendix B,2 no longer establishes arequirement for annual HCP TB testing.However, medium risk facilities willcontinue to be guided by all of theenvironmental, administrative, andmonitoring requirements that are out-lined. Appendices 1, http://links.lww.com/JOM/A780 and 5, http://links.lww.com/JOM/A784 are the adaptedversions of the 2005 MMWR CDCGuidelines’ Appendices B and C,2 withminor, bolded changes that reflect the2019 MMWR CDC/NTCA Recommen-dations’ guidance.

Travel-Related ExposureWork, educational, and volunteer-

related travel to TB endemic areas of theworld merit special mention. The 2019MMWR CDC/NTCA Recommendationsidentify any region other than Australia,Canada, New Zealand, and those countriesin western or northern Europe as likely tohave high rates of TB disease.1 Clinical










rotations and overseas duties lasting amonth or more in regions with high TBincidence (generally accepted to be morethan 20 cases/100,000 people) may pose arisk for TB exposure to HCP. The 1-monthtimeframe derives from the 2018 CaliforniaDepartment of Health Risk Assessment,55

though studies regarding TB conversions inUS HCP who travel for work are sparse.HCP who plan to engage in clinical orresearch activities with risk of exposureto active TB disease should undergo pre-and post-travel symptom screening andtesting (more than 8 weeks after return-ing).1 Serial TB screening and testingmay be warranted for HCP who rotate ona regular basis to these regions.

Voluntary Testing for Self-assessed Potential Exposure

Employees may become exposed toTB disease if incarcerated, experiencinghomelessness, have a family member/roommate from a high-risk country witha cough, or via other non-work-related sit-uations, though the annual TB test conver-sion rate of less than 1% in US HCPsupports that such conversions are uncom-mon.56 Nonetheless, facilities or sections

may decide that HCP can self-report a TBexposure concern and request a TB test withor without further inquiry by an occupa-tional health provider into the potentiallypersonal and private nature of that expo-sure. Alternatively, occupational health canencourage such HCP to seek testing fromtheir primary care provider when such aconcern arises. If the option for voluntarytesting in the workplace is offered, notifi-cation of that option should be included inthe annual education program.

Post-Exposure TestingConsiderations andInterpretation

HCP who experienced unprotectedexposure to active pulmonary or oropha-ryngeal TB should be enrolled in a contactinvestigation, ideally within 4 weeks of thefirst exposure event. This includes screen-ing for (1) symptoms and signs of TB; (2)history of prior M. tuberculosis infectionand treatment; and (3) risk of progressing toTB disease if infected with M. tuberculosis.This initial set of evaluations is to establisha baseline in the event of a change insymptoms or test conversion later. Personswith symptoms or signs suggestive of TB

disease should be evaluated for active TBpromptly. While this evaluation is ongoing,they should be restricted from work,instructed to avoid activities that couldexpose others, and reported to the publichealth department.

IGRAs are preferred for post-expo-sure testing of previously negative person-nel because of the timeliness of the results,the obviation of the need for two-steptesting, and for their higher sensitivity thanthe TST in contact investigations.13,57–59

The two-step TST procedure typically usedduring the pre-placement process (to pro-mote boosting for remote TB exposures)should not be used in contact investiga-tions.2

If the HCP has a record of a previ-ously positive TB test, the 2019 MMWRCDC/NTCA Recommendations state thatthe HCP does not require post-exposuretesting. However, standard occupationalhealth practice is to conduct testing in someof these personnel. A new TB test couldprove useful in clarifying the pre-exposurestatus and protecting the worker in the eventthat the test is now negative. Untreated HCPwith a previously positive TB test maybe considered for new baseline/initial

TABLE 2. Factors that Affect Risk of TB Transmission to Health Care Personnel (HCP)

Factors that Decrease Risk for TB Transmission to HCP

Patient Factors Environmental Factors Time and Intensity of Exposure

Early identification of possible TB diseaseof respiratory tract

Early/prompt transfer of patient intorespiratory isolation

Early initiation of effective anti-TBregimen

Effective antibiotic treatment of 3 days ormore

Patient is not coughingSurgical mask is worn by patient

Isolation room under negative air pressureRemoval of infectious droplet nuclei by

adequate air exchanges with exhaust tooutside air

Use of adequate ultraviolet germicidalirradiation (UVGI)

Employee using appropriate personalprotective equipment (PPE) (N95,powered air-purifying respirator[PAPR], or equivalent)

Risk of transmission is directlyproportional to time and intensity ofexposure

Short exposure durationInfrequent exposureAbsence of close physical contact

Factors that Increase Risk for TB Transmission to HCP

Patient Factors Environmental Factors Time and Intensity of Exposure

Incorrect, lack of, or short duration of TBtreatment

High concentrations of acid-fast bacillus(AFB) on sputum smear

Presence of coughCavitation on CXROropharyngeal or laryngeal TBFailure to cover the mouth and nose while

coughing (or not wearing a mask)Undergoing cough-inducing or aerosol-

generating procedures (eg,bronchoscopy, sputum induction,autopsy)

Culture or NAATþ regardless of AFBsmear positivity

Sharing small, enclosed spacesInadequate local or general ventilation that

results in insufficient dilution orremoval of infectious droplets

Recirculation of air containing infectiousdroplet nuclei

Inadequate cleaning and disinfection ofmedical equipment

Improper procedures for handlingspecimens

Prolonged cumulative duration of exposureFrequent exposureProlonged close physical proximityIntense exposure (eg, conducting

aerosol-generating procedures)

Partially adapted from Centers for Disease Control and Prevention.2




post-exposure TB test in a few situations,including but not limited to when:

1. The HCP had a positive TST without aconfirmatory IGRA, particularly ifBCG-vaccinated;

2. An older generation IGRA with poorerquality control or reliability was used;

3. The TST or a single IGRA was positivein an HCP without TB risk factors; and

4. There is poor or absent documentationof the previous positive TB result.

In contrast, if it is determined duringthe course of taking the history that the

HCP has had treatment for LTBI or activeTB disease, testing may not be indicated(Table 3).

Management of contact investiga-tions and interpretation of results forHCP can be nuanced. Table 3 offers asuggested workflow for such investigations.The interpretation of the initial test result(less than 4 weeks from first significantexposure) should be as follows:

� A negative test result should be retestedmore than 8 weeks following cessationof suspected exposure. A negative test

result obtained less than 8 weeks afterexposure is considered unreliable forexcluding infection due to the timeneeded for the body to mount a reliableimmune response.

� A positive test result indicates that aprior infection is likely. Evaluation andtreatment are recommended. A follow-up TB test in more than 8 weeks isnot indicated.

If the initial post-exposure TB test isnegative or is not obtained within 4 weeksof the first exposure, contacts shouldundergo TB testing no sooner than 8 to

TABLE 3. Management of HCP Exposed to Potentially Infectious Tuberculosis

HCP TB Status Prior to Known TB Exposure

Time Frame Clinical Management

Negative IGRA or

TST <3 Months

Ago

Negative IGRA or TST

�3 Months Ago or Unknown

or Unavailable Results

Positive IGRA

or TST,

Untreated

Positive

IGRA or TST,

Treated

As soon as TB exposureis identified, up to4 weeks after firstexposure�

Step 1 TB symptom screen Yes Yes Yes Yes

Step 2 Obtain initial post-exposuretest (IGRA or TST)y

Optionalz Yes Conditional§ No

Step 3 If initial post-exposure test ispositive, or if TBsymptoms are reported,obtain CXR and focusedclinical examinationjj

Yes Yes Yes Yes

Step 4 Recommend LTBI treatmentif initial post-exposuretest is positive withoutevidence of active TBdiseasejj

Yes Yes Yes Rare��

At least 8 weeks afterlast exposure�,{

Step 5 TB symptom screen Yes Yes Yes Yes

Step 6 Obtain follow-up post-exposure test# if initialpost-exposure test wasnegative or not obtained

Yes Yes Yes§ No

Step 7 Obtain CXR and performfocused clinicalexamination if symptomscreen or post-exposuretest is positivejj

Yes Yes Yes Yes

Step 8 Recommend LTBI treatmentif this post-exposure testis positive withoutevidence of active TBdiseasejj

Yes Yes Yes Rare��

�Tests for TB infection obtained between 4 and 8 weeks after TB exposure serve neither as a valid baseline nor as a follow-up test, and are not recommended except, potentially, inthe case of severe immunocompromised status or extenuating circumstance. If exposure identification was made after 4 weeks, commence with Steps 5 to 8 after 8 weeks using the lastknown test as the baseline.

ySome references may call this first post-exposure test a new ‘‘baseline’’ result. An interferon-gamma release assay (IGRA) is preferred over tuberculin skin testing (TST) for usein contact investigations. If TST must be used, note that if the previous TST result is >12 months old, two-step TST testing would be ideal, if feasible, for the 1st post-exposure test.IGRA is strongly preferred because this is difficult to accomplish in a timely manner and delays in the two-step testing process can cause confusing results.

zThe first post-exposure test may have limited value in HCP who had a negative IGRA or TST in the past 3 months, though it may be required by the facility or workers’compensation; check local policy. An IGRA could be useful for use in individuals who have only had TSTs.

§Obtain an IGRA for those with a previously positive test if (1) TST is the only test that was previously positive (particularly in BCG-vaccinated individuals) or (2) an earlierIGRA was positive on only one instance and not confirmed by a repeat test. If the LTBI diagnosis was confirmed, repeat testing is not necessary.

jjIf there is any suspicion of active TB disease, expert consultation should be obtained.{HCP who are identified as TB contacts >8 weeks following last exposure to active TB disease should still be clinically managed as soon as possible as in Steps 5 to 8.#Using the same test method as the first post-exposure test (if obtained) is preferred.��Those with prior TB treatment may benefit from re-treatment, depending on exposure history, post-exposure test results, and risk factors, such as HIV infection, solid-organ

transplant or ongoing treatment with a TNF-alpha inhibitor. Consultation with a specialist or the public health department is recommended.




10 weeks after the last exposure, or as soonas possible if this time window is missed.Re-testing with the same method as theinitial test is recommended to minimizevariability in results. Re-testing after atleast 8 weeks from the last exposure allowsthe immune system time to mount a reliableresponse to M. tuberculosis if sufficientexposure occurred. If either symptomscreening or the TB test is positive, addi-tional steps (such as physical examinationand chest radiographs) are required to diag-nose LTBI or active TB disease.

The interpretation of the follow-uptest result (more than 8 weeks after lastexposure) should be as follows:

� A negative TST or IGRA test result morethan 8 weeks after the end of exposureindicates that M. tuberculosis infectionis unlikely. A negative test resultobtained less than 8 weeks after expo-sure is considered unreliable for exclud-ing infection.

� A positive TSTor IGRA result more than8 weeks after the final exposure suggeststhat M. tuberculosis infection hasoccurred since prior testing (conver-sion). HCP with newly diagnosed M.tuberculosis infection should have asymptom review, CXR, and evaluationfor progression to active TB. For thosediagnosed with LTBI, treatment shouldbe encouraged. If the recommendationfor treatment is not accepted initially,annual symptom reviews should com-mence, and annual education shouldreinforce treatment options. The publichealth department should be notified ofany suspected transmissions.

SERIAL SCREENING, TESTING,AND EDUCATION FOR HCP

2019 MMWR CDC/NTCA Recommen-dation: ‘‘In the absence of knownexposure or evidence of ongoing TBtransmission, US health care personnel (asidentified in the 2005 guidelines) withoutLTBI should not undergo routine serial TBscreening or testing at any interval afterbaseline (ie, annually). Health carefacilities might consider using serial TBscreening of certain groups who might beat increased occupational risk of TBexposure (eg, pulmonologists orrespiratory therapists) or in certainsettings if transmission has occurred inthe past (eg, emergency departments).Such determinations should beindividualized on the basis of factors thatmight include the number of patients withinfectious pulmonary TB who are examinedin these areas, whether delays in initiatingairborne isolation occurred, or whetherprior annual testing has revealed ongoingtransmission. Consultation with the local orstate health department is encouraged toassist in making these decisions.

Health care personnel might have risks forTB exposure that are not related to work inthe United States, or they might have risksfor TB progression after baseline testing thatnecessitate special consideration. If theserisks are unrecognized, these health carepersonnel might experience TB diseaseand transmit TB to patients, coworkers, orother contacts. Therefore, health carefacilities should educate all health carepersonnel annually about TB, includingrisk factors, signs and symptoms; facilitiesalso should encourage health carepersonnel to discuss any potentialoccupational or nonoccupational TBexposure with their primary care providerand occupational health clinician. Thedecision to perform TB testing afterbaseline should be based on the person’srisk for TB exposure at work or elsewheresince that person’s last test.’’1

The 2019 MMWR CDC/NTCARecommendations state that the riskassessment for health care settings (foundin Appendices B and C in the Guidelinesfor Preventing the Transmission of Myco-bacterium tuberculosis in Health-CareSettings, 20052) no longer forms the basisfor determining a TB testing regimen forHCP, and that HCP without LTBI shouldnot undergo routine serial TB screeningor testing at any interval after baseline (ie,annually) in the absence of known expo-sure or evidence of ongoing TB transmis-sion. This is part of the updated approachto TB elimination in US health care set-tings. Driving the new recommendationare current TB rates among HCP match-ing those of the general population,11 theinherent limitations in predictive value ofscreening tests administered among lowrisk populations,60 and the public healthimperative to be proactive and treat LTBI.For more information regarding the sup-porting data, refer to ‘‘Background withLiterature Review’’ section of this docu-ment.

Serial Screening and TestingThe 2019 MMWR CDC/NTCA Rec-

ommendations instruct not to conduct rou-tine serial TB screening or testing at anyinterval after hire in the absence of knownexposure, but state that health care facilities‘‘might consider’’ serial TB screening forcertain groups at increased occupationalrisk (citing pulmonologists or respiratorytherapists as possible examples)61 or forpersonnel working in settings with pastdocumented transmission. Additionally,other HCP may have institutional or regu-latory requirements for serial testing, suchas laboratory personnel performing micro-biological specimen testing for TB.62,63

The new guidance further instructs thatany decision to extend such serial testing

should be individualized based upon crite-ria including:

1. The number of patients with infectiouspulmonary TB examined;

2. Whether delays occurred in initiatingairborne isolation;

3. Whether environmental controls andprocesses, such as patient maskingand air handlers are in place and arefunctional; or

4. If prior serial testing has revealedongoing transmission.

When there is any concern or uncer-tainty, consultation with public health isrecommended. Current state and local reg-ulations may be in conflict with this newfederal guidance and may require routineTB testing for certain groups until suchregulations change.

A specific threshold number ofactive TB cases that would trigger serialsurveillance testing is not identified as itwas in the 2005 MMWR CDC Guidelines(Appendix 5, http://links.lww.com/JOM/A784).2 Instead, the recommendationsadvise that clinical staff involved in thedirect care of patients with active pulmo-nary TB on a regular and ongoing basis mayconstitute personnel at increased risk.Examples of such increased risk wouldinclude HCP in a TB clinic who encounterpatients with TB before initiation of air-borne isolation, or individuals involveddirectly and frequently in cough-inducingor aerosol generating procedures onpatients with active pulmonary TB. Staffinvolved in autopsy examinations in an areawith high rates of TB, and laboratoriansmanipulating specimens or cultures with alarge TB burden, may warrant further con-sideration for inclusion in serial screeningor testing programs.63–66 While there doesnot appear to be current published evidencein the US of higher LTBI incidence amongthose employees, such clinical settings havebeen associated with occupational trans-missions in the past. Any extension ofserial/annual testing to individual HCPshould take into account the specific work-place clinical setting, its environmental andsafety controls, and its volume of active TBcases seen where such precautions have ormay fail. In situations where serial testing isconsidered, positive IGRA results should beconfirmed (repeated) given the higher ratesof conversions and reversions comparedwith the TST.20,67 It is worth re-stating thatthere is a paucity of recent literature report-ing occupational transmission of TB toany specific group of US hospital-basedpersonnel.

The second criterion, delays ininitiating airborne isolation, is largelyaddressed within the recommendationsfor post-exposure TB surveillance (see






preceding section, ‘‘Post-Exposure Screen-ing and Testing’’). An instance in whichsuch a delay occurs for a patient with activeTB disease should generally be regarded asan exposure, triggering baseline, and fol-low-up TST or IGRA testing as per currentguidance. Instances of delayed isolationshould be identified and handled as spe-cific exposure events. Settings in whichsuch delays may be more likely and fre-quent would include patient care environ-ments in regions of the world with highrates of active TB, to which US HCP mayperiodically rotate. Increased risk of TBamong HCP continues to be a substantialhazard in such settings.68,69 We recom-mend that a clinical rotation to TB-endemic regions of the world be consideredan increased risk for TB exposure and thuswarrant post-travel testing, and that serialscreening be considered for the HCP whorotates on a regular basis to higher riskinternational settings. Those who rotateonly rarely or intermittently to suchsettings should be considered for post-exposure TB surveillance upon return tothe US, regarding the time in the higherrisk setting as an interval of potentialexposure.

The third criterion addresses settingsin which the risk of TB exposure may beinadequately characterized but where pastexperience in monitoring LTBI conversionamong HCP has suggested enhanced risk(as evidenced by annual testing thatrevealed ongoing transmission). Such set-tings offer the opportunity to better under-stand and mitigate risk factors for TBtransmission (ie, enhanced environmentalcontrols), and may benefit from continuedserial surveillance in order to assess theimpact of risk factor mitigation efforts.Encouragement in the new guidance toconsult with local or state health depart-ments prior to continuing any serial screen-ing is sound, since ongoing screening islikely to be based on local factors ratherthan the general trends recognized in recentyears for US HCP.

Annual Education RequirementWith implementation of the new

guidance, rigorous annual TB educationfor HCP will take on greater importance.This is due both to the elimination ofwidespread serial surveillance testingand the intent of the guidance to encour-age more treatment of LTBI in HCP.Educational programs should addressthe range of TB-related issues with whichall staff should be familiar: exposure risks(both within and outside of the work-place), what to expect if a workplaceTB exposure is identified, signs andsymptoms of active disease, and whichworkplace-based and non-workplace-

based medical resources to access ifsymptoms develop. Staff should bereminded of the option for voluntaryTB testing if it is offered. Additionalattention should be given to specificknowledge required by HCP who haveuntreated LTBI and to those who maybe at increased TB risk due to work-related or non-work-related factors (suchas immune suppression70; see Appendix6, http://links.lww.com/JOM/A785).

Importantly, the 2019 MMWRCDC/NTCA Recommendations do notinclude the recommendation to conductan annual individual risk assessment forHCP (eg, asking employees where theytraveled outside of work). The recommen-dation to conduct the annual facility riskassessment (2005 MMWR CDC Guide-lines Appendix B,2) does remain inplace. Individuals with increased riskfor occupational exposure (eg, engagingin aerosolizing procedures in facilitiesthat routinely diagnose TB) should beidentified by the facility risk assess-ment, and may be considered for serialtesting. Serial testing for targeted staffcan also be appropriate when environ-mental controls have been shown or arestrongly suspected to have failed, asdemonstrated by evidence of trans-mission without knowledge of a specificexposure.

Messages specifically directed atthose with untreated LTBI to be aware ofsymptoms suggestive of active disease andto promptly report any such symptoms tooccupational health should be folded intogenerally targeted educational modules.Annual education can help establish theknowledge base necessary to enhance per-sonal awareness of potential signs andsymptoms of TB. While such educationcould be accomplished with a widelydirected teaching module, face-to-faceencounters with occupational health pro-viders do add value by providing the oppor-tunity to teach, ask questions, and allayemployee concerns. Most importantly, edu-cating untreated staff regarding short-course treatments that are equally effective,have much higher compliance rates and aregenerally well tolerated can result in bothindividual and public health benefits(Fig. 1).

Annual Symptom Review forHCP with LTBI

The 2019 MMWR CDC/NTCA Rec-ommendations do continue to support anannual symptom evaluation for those withuntreated LTBI1 (Appendix 7, http://links.lww.com/JOM/A786). This symptom sur-vey should include education to help theHCP with treated or untreated LTBI

understand which symptoms to monitor,whom to contact if symptoms of concerndevelop, and what LTBI treatment optionsto consider. While there is a paucity ofliterature showing efficacy of annual symp-tom surveys to detect active TB disease, therequired annual symptom screening can bea useful point of contact to review theHCP’s knowledge and understanding ofTB and to encourage treatment of LTBIfor those who have not previously acceptedrecommendations.

Importantly, the symptom assess-ments among those with LTBI should becarried out with an awareness of the possi-bly stigmatizing effect of singling out aspecific group of HCP for serial surveil-lance due to LTBI positivity. Medical cen-ter occupational health clinics have oftenrelied upon communication with managersto enforce adherence to serial TB surveil-lance programs, but this strategy couldhave the unintended consequence of sug-gesting the presence of TB infection to anindividual’s manager. To avoid this, adher-ence with annual symptom monitoringshould be enforced to the extent possiblethrough direct communication from occu-pational health to the HCP with LTBIrather than through the HCP’s manageror supervisor. Options include regularmail, direct e-mail with a linked symptomsurvey, telephonic assessment, or in-per-son interview. If communication with amanager to enhance adherence is deemednecessary, it should state only that theemployee has an occupational healthrequirement to be addressed.

Transitioning a TB ScreeningProgram for Health CarePersonnel

The vast majority of health carefacilities will be able to eliminate serialTB testing thereby saving time and moneythat may be redirected to activities such aseducating, identifying, tracking, and treat-ing LTBI. Some programs will have tran-sient impediments to getting to this futurestate that may include mandatory testing bylocalities and states, updating of hospitalpolicies, contracts that specify TB testing,and general resistance to change. The tran-sition will require consistent, reassuringcommunication that emphasizes that thesafety of HCPs and patients should beimproved by the pre-placement identifica-tion and treatment of LTBI, and identifica-tion and monitoring of those exposed toactive TB cases. It is worth reiterating thatthe decades of serial TB screening programresults, in conjunction with improvementsin environmental controls, show the UShas had a substantial reduction in TBburden.







TREATMENT AND EDUCATIONOF HEALTH CARE PERSONNEL

WITH POSITIVETEST RESULTS

2019 MMWR CDC/NTCA Recommen-dation: ‘‘Health care personnel with anewly positive test result (withconfirmation for those persons at low riskas described previously) should undergo asymptom evaluation and chest radiographto assess for TB disease. Additional workupmight be indicated on the basis of thoseresults. Health care personnel with a priorpositive TB test and documented normalchest radiograph do not require a repeatradiograph unless they are symptomatic orstarting LTBI treatment. The local publichealth department should be notifiedimmediately if TB disease is suspected.Health care personnel with LTBI and noprior treatment should be offered, andstrongly encouraged to completetreatment with a recommended regimen,including short-course treatments, unless acontraindication exists. Health carepersonnel who do not complete LTBItreatment should be monitored withannual symptom evaluation to detectearly evidence of TB disease and toreevaluate the risks and benefits of LTBItreatment. These health care personnelalso should be educated about the signsand symptoms of TB disease that shouldprompt an immediate evaluation betweenscreening visits.’’1

Progression from LTBI to TBDisease (Reactivation TB)

The vast majority of TB disease inthe US is caused by the progression fromlatent infection to active disease (reactiva-tion). Eighty-percent of the nearly 40,000active TB cases reported in the US between2006 and 2008 were reactivation TB,largely in non-US born persons.47 Over60% of these persons progressed more than4 years after they arrived in the UnitedStates.71 The rate of progression from LTBIto active TB disease was slightly higheramong non-US born than US born per-sons.72 Finding and treating LTBI, whetherrelated to a contact investigation from anexposure or as identified during the POPPevaluation, both act to reduce the possibilityof future cases. Preventing progressionfrom LTBI to active TB disease in HCPmerits particular attention because activedisease often goes unrecognized for weeksto months and exposes large numbers ofcolleagues, vulnerable patients, and theirfamilies. Contact investigations associatedwith HCP who progress to TB disease cancost millions of dollars, result in negativemedia attention and cause significantharm.73

Educating HCP about LTBIWhen HCPs with LTBI are evaluated

at occupational health for consideration of

treatment, the importance of education can-not be overstated. The goal is to teach HCPabout their diagnosis, the risk of developingactive TB disease, treatment options, andthe benefits and risks of treatment. Onceactive TB disease is ruled out, the followingkey concepts should be clearly conveyed:

� You have LTBI, not active TB disease.� The BCG vaccine does not interfere with

the accuracy of the TB blood tests.� When you have LTBI, it is not conta-

gious so you cannot pass this toother people.

� You can be at work.� You are at risk of developing active TB

disease in the future.� The risk of developing active TB

depends on your health status and howrecently you were infected.

� During the first 2 years after infection,the risk starts at about 5%, but can bemuch higher in some people.

� After the first 2 years the risk starts atabout 1% per decade of life but can bemuch higher.

� Conditions and medications that youmay have now or in the future couldsubstantially increase that risk, includingHIV infection, diabetes, cancer, lungdisease, tobacco use, and immune sup-pression from medications and aging.

� If you develop active TB disease youmay expose patients, coworkers, and

FIGURE 1. LTBI treatment options quick-reference guide, 2020. �Rifapentine: 25.1 to 32.0 kg, 600 mg; 32.1 to 49.9 kg, 750 mg;more than or equal to 50.0 kg, 900 mg maximum. See Table 4 for list of abbreviation meanings.




family. Some of these people may be athigh risk of developing active TB andserious complications of the diseaseincluding death.

� Treatment of LTBI is safe, effective, andstrongly recommended in most cases.

� Treatment of LTBI can be as short as1 day per week for 12 weeks (Fig. 2).

Recommending TreatmentSince more than 80% of active TB

cases in the US arise from previouslyuntreated LTBI,47 LTBI represents aunique opportunity to prevent a potentiallydevastating infectious disease via earlytreatment. For this reason, treatment ofLTBI is now a cornerstone of the nation’sTB elimination strategy.75 Treatment isnow strongly recommended for HCP withLTBI, unless risks of treatment outweighthe anticipated benefit for a particularpatient. A CXR prior to the time of treat-ment initiation is recommended by theCDC; 3 to 6 months is a reasonable time-frame for needing to repeat a CXR priorto treatment.

The use of IGRAs increased accep-tance of LTBI treatment compared withTST. In one study, that acceptance rateincreased from 11% to 52% with positiveresults.41 However, there is a concerning,consistent finding that HCP with LTBI areless likely than non-HCP to accept LTBItreatment.38–40,42 Treatment acceptancerates vary but seem to cluster between40% and 50% when all eligible HCP areincluded.10,38,39,41,76,77 Acceptance rates ashigh as 90% with adherence have beenreported with intensive clinic interventionsincluding frequent follow-up visits. Selec-tion bias may limit the reproducibility ofthese findings.77,78

The reasons for low HCP acceptanceof treatment are unclear. Recent data sug-gest that physicians and HCP from high TBburden countries may be less likely toaccept and complete treatment comparedwith other HCP.76,79 One potential contrib-utor may be greater familiarity with isonia-zid (INH) treatment-associated adverseevents. Newer regimens afford not onlyshorter, but safer courses of treatment,

and therefore may be more acceptable toHCP. The consequences of active TB inHCP are potentially more serious than inthe general population because they includenot only personal illness but also costly anddisruptive contact investigations, lost worktime and an appreciable risk of exposingmedically vulnerable patients.80–84 Consid-eration of these factors may convince oth-erwise ambivalent HCP to accept treatment.

Occupational health programsshould utilize strategies to reduce barriersto treatment and optimize treatment accep-tance and completion. Such strategies mayinclude:

� Offer treatment through an onsite occu-pational health clinic.

� Provide LTBI education appropriate tothe HCP’s knowledge base.

� Elicit and address the HCP’s beliefsand concerns about LTBI and LTBItreatment.

� Subsidize the cost of treatment.� Offer flexible, convenient mechanisms

for follow-up care.

FIGURE 2. NTCA provider guidance: using the Isoniazid/Rifapentine regimen to treat latent tuberculosis infection (LTBI). Source:Tuberculosis Controllers Association. NTCA provider guidance: using the Isoniazid/Rifapentine regimen to treat latent tuberculosisinfection. November 2019; Revised April 2019. Available at: http://www.tbcontrollers.org/docs/resources/3hp/NTCA_Provider_-Guidance_3HP_11918.pdf.74



http://www.tbcontrollers.org/docs/resources/3hp/NTCA_Provider_Guidance_3HP_11918.pdf



� Follow up with HCP who do not accepttreatment initially.

� Use a declination form to clearlydocument the offer of treatment andunderscore the educational messages(Appendix 4, http://links.lww.com/JOM/A783).

Nine months of daily isoniazid(9INH) has long been a standard regimenused in the US for the treatment of LTBI.Clinical studies have indicated it can behighly effective in preventing progressionto active TB, but adherence rates are typi-cally suboptimal. Six months of daily INH(6INH) is another acceptable regimen, butagain the high adherence rates required foroptimal efficacy have been difficult toachieve. Both long course INH treatmentregimens are associated with rare compli-cations including mild-to-severe hepatocel-lular toxicity.

Currently, there are three short-course treatment regimens for LTBI thatare recommended over 6INH and 9INH:12 weeks of once-weekly INH and rifapen-tine (3HP), 3 months of daily INH plusrifampin (3HR), and 4 months of dailyrifampin alone (4R). Each of these shortregimens are now preferred first-line thera-pies, supplanting the long course INHoptions.85–87 The short-course therapies

have been shown to have equal or greaterefficacy at preventing progression to activeTB, significantly higher completion rates,and superior safety profiles when comparedwith 9INH.88–90 Even shorter regimenscontinue to be studied.91 When prescribingrifampin-based regimens, the potential fordrug–drug interactions should be carefullyconsidered and monitored. An LTBI treat-ment comparison table is offered in Fig. 1,and a 3HP user Guide is included in Fig. 2.

Some HCP who initially declinetreatment may change their mind in subse-quent years as medication regimens andinfluences in their personal lives alsochange. For those who decline or defertreatment, a mechanism to periodicallyreissue the offer and to educate them onnew treatments as they become available isrecommended and could be embedded inongoing TB awareness education or respi-ratory fit testing. Resources for LTBI diag-nosis, education, and treatment areavailable through CDC,92 and its fourregional TB Centers of Excellence forTraining, Education, and Medical Consul-tation,93 as well as the NTCA.94

CONCLUSIONThe epidemiology of tuberculosis in

the US is changing, and diagnostic tests andtreatment regimens for TB are evolving.Occupational health providers shouldimplement policies and protocols basedon the current science. The 2019 MMWRCDC/NTCA Recommendations represent aphilosophy and approach that focuses oneducating all HCP and on treating HCPidentified with LTBI to minimize the pro-gression to active disease and infectious-ness. In this companion document, we havesought to provide practical context for therecommendations. Occupational healthpractitioners should bear in mind that the2019 MMWR CDC/NTCA Recommenda-tions exist within the regulatory environ-ment, and that some states or localgovernments may still have annual TBtesting requirements for HCP. Over time,the regulations will evolve and allow thisACOEM/NTCA Companion Guidance tobe used for occupational health practi-tioners who will implement work-basedprograms.

In addition to promoting health andpreventing disease, the new recommenda-tions should improve the efficiency andeffectiveness of occupational health practi-ces in health care facilities. The require-ment for routine, serial, untargeted annualtesting is no longer justified. This approachhas generated tens of millions of negativeTB test results and has occupied hundredsof thousands of hours of occupationalhealth time, HCP time, and significant fis-cal resources each year without providing

significant improvement in either HCP orin-patient health. Policies that called forlarge-scale serial testing without attentionto preventive treatment also generatedmany false-positive results and has resultedin additional unnecessary testing and treat-ment of people without TB. The waste andharm associated with tens of millions ofnegative TB tests annually also contributesboth enormous medical waste and a sub-stantial carbon footprint that negativelyimpact the planet as a whole.95

It is a true public health feat that theUS is on its way to elimination of a diseasethat just 100 years ago killed one in sevenAmericans, and still kills 1.6 million peopleacross the globe annually. The decline ofTB in the US overall, and in HCP inparticular, is remarkable in a country aslarge and as diverse as the US; the elimina-tion of TB disease by proactively treatingLTBI should be the US health care com-munity’s next collective priority. These aretestaments to what we can do together whengood science and good practice beget goodpolicy.

ACKNOWLEDGMENTSACOEM and NTCA wish to thank the

section leaders for this document: RandallReves, MD (Background with LiteratureReview), Amy Behrman, MD (Baseline(post-offer/pre-placement) Screening andTesting), Jon Warkentin, MD, MPH (Post-exposure Screening and Testing), MarkRussi, MD, MPH (Serial Screening, Testingand Education for HCP), and MelanieSwift, MD, MPH (Education and Treatmentof HCP with Positive Test Results). Theyalso wish to thank the NTCA Boardmembers and Paul J. Papanek MD, MPH,for their contribution as reviewers tothis document.

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TABLE 4. Abbreviations

3HP 3 months INHþ rifapentine(once weekly)

4RIF 4 months rifampin (daily)6INH 6 months INH (daily)9INH 9 months INH (daily)AFB Acid-fast bacillusAIDS Acquired Immunodeficiency

SyndromeBAMT Blood assay for M. tuberculosisBCG Bacille Calmette-GuerinCDC Centers for Disease Control

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