TB Infection Cascade Results Before and After Changing the TST Induration Threshold, Vietnam
| TB InfectionaDiagnostic Tests, No. | TB Infection Test Results, No. (%) | Positive TB Infection Test Results, No. (%) | Eligible for TPT After Excluding TB Disease, No. | Initiated on TPT, No. (%) | |
|---|---|---|---|---|---|
| March 2020–October 2021: TST threshold ≥10 mm | |||||
| ACF community campaigns | 25,378 | 25,320 (99.8) | 3,190 (12.6) | 3,101 | 1,674 (54.0) |
| November 2021–December 2022: TST threshold ≥5 mm | |||||
| ACF community campaigns | 7,334 | 7,174 (97.8) | 1,936 (26.4) | 1,885 | 1,497 (79.4) |
Abbreviations: ACF, active case-finding; QFT, QuantiFERON-TB Gold Plus; TPT, TB preventive treatment; TST, tuberculin skin testing.
↵a TB infection was diagnosed using TST; in a subset of individuals (2,887 [8.8%]) who received both TST and QFT for quality assurance, a positive TST or QFT result yielded a diagnosis of TB infection. COVID-19 pandemic restrictions decreased the number undergoing TB infection evaluation in 2022.