Work

Tuberculosis transmission and community outreach screening in an informal urban settlement in a low-incidence European setting

Year: 2026

Type: article

Abstract: Background Tuberculosis (TB) in low-incidence European settings disproportionately affects structurally vulnerable populations, including individuals living in informal housing. In late 2023, a TB cluster was identified among residents of an occupied building in Badalona, Spain. We report the implementation and outcomes of a community-based active TB screening intervention conducted in response. Methods We conducted a descriptive field investigation between October 2024 and February 2025 in an occupied former school that served as a residence and social hub for approximately 150 individuals (residents and non-resident community members). Three on-site interventions combined health education, symptom-based screening, and clinical assessment. Individuals with TB-compatible symptoms were referred for chest radiography and microbiological testing (smear microscopy, culture, and Xpert MTB/RIF Ultra) according to national protocols. WHO-recommended screening cascade indicators were calculated. Additional TB cases epidemiologically linked to the settlement were identified through surveillance data. Findings Eighty-one individuals were screened (54% of approximately 150 individuals connected to the settlement). Twelve presumptive TB cases were identified; all completed diagnostic evaluation. Three new TB cases were diagnosed through screening (number needed to screen = 27; number needed to test = 4). Two started treatment, and both completed it and were cured; the third never started treatment and was lost to follow-up. Overall, 11 TB cases were epidemiologically linked to the settlement (10 bacteriologically confirmed and one clinically diagnosed). The intervention also facilitated linkage to primary healthcare services. Operational challenges included high mobility, incomplete population enumeration, limited transport support, and institutional mistrust. Interpretation Active TB transmission can persist in informal urban settlements in low-incidence settings. Community-based outreach screening is feasible but operationally fragile and dependent on timely identification, institutional coordination, and social support to ensure adequate coverage and continuity of care.

Source: Frontiers in Public Health

DOI: 10.3389/fpubh.2026.1907926