Tuberculosis screening in outpatient healthcare workers: lessons from a high-income, low TB burden country

SETTING: Early diagnosis of latent tuberculous infection (LTBI) should be pursued in healthcare workers (HCWs). While HCWs in hospitals are screened for LTBI, HCWs in outpatient settings are usually not. In 2017, in Italy, a tuberculosis (TB) infected paediatrician working in an outpatient vaccination service infected 15 adults and nine children. The investigation involved 2490 children and 151 adults. Among children, nine were tuberculin skin test-positive, and four developed active TB. Among 123 adult contacts with longer exposure, seven were interferon-gamma release assay (IGRA) positive and none had active TB. Among 28 close contacts, eight had a positive IGRA, and three had pulmonary TB. The total outbreak cost €1 017 903.OBJECTIVE: To compare the outbreak cost with those of potential screening programme strategies.RESULTS: Regular screening of paediatric outpatient HCWs would have cost between €2592 and €11 373. Extending the screening to all outpatient HCWs (caring for adults and children) would have cost between €66 384 and €155 043. Investigating only close contacts would have cost €42 857.CONCLUSION: Each of these screening strategies would have been cost-effective compared with the outbreak investigation occurring in real life with a cut-off of 474 for the maximum number of tested outpatient HCWs needed for the screening strategy to be cost-saving.