title: Priorities for screening and treatment of latent tuberculosis infection in the United States.
abstract: BACKGROUND
  To improve the effectiveness of tuberculosis (TB) control programs in the United States by identifying cost-effective priorities for screening for latent tuberculosis infection (LTBI).
  
  
  OBJECTIVE
  To estimate the cost-effectiveness of LTBI screening using the tuberculin skin test (TST)and interferon-g release assays (IGRAs).
  
  
  METHODS
  A Markov model of screening for LTBI with TST and IGRA in risk-groups considered in current LTBI screening guidelines.
  
  
  RESULTS
  In all risk-groups, TST and IGRA screening resulted in increased mean life expectancy, ranging from 0.03–0.24 life-months per person screened. IGRA screening resulted in greater life expectancy gains than TST. Screening always cost more than not screening, but IGRA was cost-saving compared with TST in some groups. Four patterns of cost-effectiveness emerged, related to four risk categories. (1) Individuals at highest risk of TB reactivation (close contacts and those infected with HIV): the incremental cost-effectiveness ratio (ICER) of IGRA compared with TST was less than $100,000 per quality-adjusted life year (QALY) gained. (2) The foreign-born: IGRA was cost-saving compared with TST and cost-effective compared with no screening (ICER ,$100,000 per QALY gained). (3) Vulnerable populations (e.g., homeless, drug user, or former prisoner): the ICER of TST screening was approximately $100,000–$150,000 per QALY gained, but IGRA was not cost-effective. (4) Medical comorbidities (e.g., diabetes): the ICER of screening with TST or IGRA was greater than $100,000 per QALY.
  
  
  CONCLUSIONS
  LTBI screening guidelines could make progress toward TB elimination by prioritizing screening for close contacts, those infected with HIV, and the foreign-born regardless of time living in the United States. For these groups, IGRA screening was more cost-effective than TST screening.
authors.affiliation: HIV Epidemiology and Outcomes Research Unit, Boston Medical Center, Section of Infectious Disease, Evans Biomedical Research Center, 650 Albany St. Rm 647, Boston, MA 02118, USA. benjamin.linas@bmc.org
authors.forename: Benjamin P
authors.initials: BP
authors.lastname: Linas
authors.forename: Angela Y
authors.initials: AY
authors.lastname: Wong
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Freedberg
authors.forename: C Robert
authors.initials: CR
authors.lastname: Horsburgh
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D016358:Contact Tracing / Q000191:economics / Q000379:methods; D017046:Cost Savings; D003362:Cost-Benefit Analysis; D005260:Female; D006801:Humans; D015994:Incidence; D007371:Interferon-gamma / Q000378:metabolism; D055985:Latent Tuberculosis / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D008297:Male; D008403:Mass Screening / Q000191:economics / Q000379:methods / Q000592:standards; D008875:Middle Aged; D018803:Models, Economic; D009017:Morbidity / Q000639:trends; D017410:Practice Guidelines as Topic; D015995:Prevalence; D019057:Quality-Adjusted Life Years; D012189:Retrospective Studies; D014374:Tuberculin Test / Q000191:economics*; D014481:United States / Q000453:epidemiology; D055815:Young Adult
chemical_list: D007371:Interferon-gamma