Serial Mass Tuberculosis Screening Among the Elderly in Eastern China from 2021-2023

The impact of repeated community-wide tuberculosis screening is uncertain because evidence from large-scale, multi-round screening campaigns is limited.

We evaluated whether annual, community-based, chest-radiography screening was associated with reduced tuberculosis prevalence and detection of asymptomatic disease across multiple screening rounds.

We conducted three annual chest X-ray screening rounds (2021-2023) among adults aged ≥60 years in Lanxi City, Zhejiang Province. All participants underwent chest radiography at community health centers, with referral for diagnostic evaluation and bacteriological testing. We estimated detection yields per 100,000 screened persons, assessed trends, and used direct standardization and repeated-participation analyses.

Across all rounds, 214,948 screening encounters were completed. From Round 1 to Round 3, screening-detected prevalence declined for overall tuberculosis (233.1 [95% CI, 194.2-279.7] to 146.3 [95% CI, 123.1-173.9] per 100,000 screened persons) and bacteriologically-confirmed tuberculosis (162.1 [95% CI, 130.3-201.7] to 108.6 [95% CI, 88.8-132.7] per 100,000 screened persons). From Round 1 to Round 3, asymptomatic tuberculosis decreased as both a proportion of cases (47.8% to 26.6%) and prevalence among screened participants (111.5 to 38.9 per 100,000). Compared with Round 1, tuberculosis prevalence was lower in Round 2 (-28.1% change; 95% CI, -44.0 to - 7.5) and Round 3 (-37.2% change; 95% CI, -51.2 to - 19.2). The Round 2-to-Round 3 difference was smaller and included the null (-12.8% change; 95% CI, -31.7 to 11.4). Standardization and repeated-participation analyses yielded broadly similar patterns.

Serial community-level screening was associated with declining tuberculosis prevalence, including asymptomatic disease, with the largest reduction occurring between the first and second screening rounds.