Impact of COVID-19 on tuberculosis diagnosis in a low-incidence southern European city

INTRODUCTION: Delayed diagnosis and treatment initiation of tuberculosis (TB) are linked to higher community transmission and mortality. The COVID-19 pandemic disrupted TB control programs globally. This study evaluates the impact of the pandemic on TB management in a Barcelona hospital. Objectives were to analyze diagnostic delays, patient characteristics, and outcomes before and after the pandemic and assess its effect in a low-incidence setting. METHODS: A prospective cohort study was conducted at a single center, including 143 patients with microbiologically confirmed pulmonary or extrapulmonary TB diagnosed between 2018 and 2023. Socio-demographic, clinical, radiological, and outcome data were collected. Pre- and post-pandemic periods were compared using Chi-square and Mann-Whitney U tests. RESULTS: Immigrant patients had shorter diagnostic delays than local patients (30 vs. 60 days, p=0.004). Patients with extrapulmonary TB showed longer delays than those with pulmonary TB (30 vs. 24 days, p=0.001). When comparing the three study periods, during the pandemic the number of pulmonary TB cases increased (52% vs. 79%, p=0.018) as did the proportion of smear-positive patients (29% vs. 55%, p=0.028), while the diagnostic delay decreased, with the lowest median recorded (20.5 days). CONCLUSION: These findings highlight the importance of resilient healthcare systems. Early detection, personalized treatment strategies, and strengthened public health initiatives targeting high-risk populations can improve outcomes and reduce TB transmission, even during global health crises.