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.