Work

Paradoxical changes in tuberculosis diagnostic delay and bacteriological positivity across COVID-19 pandemic phases: a retrospective cohort study in Taiwan

Year: 2026

Type: article

Abstract: Background The COVID-19 pandemic has substantially disrupted healthcare systems and may have influenced tuberculosis (TB) diagnosis through changes in healthcare access, diagnostic pathways, and respiratory disease surveillance. However, evidence remains limited regarding how these changes affected TB diagnostic intervals and case detection across different pandemic phases. Methods This retrospective cohort study included adult patients with newly diagnosed pulmonary TB at a medical center in southern Taiwan between 2017 and 2024. Patients were categorized into three periods: pre-pandemic, pandemic, and post-pandemic. Clinical characteristics, diagnostic intervals, and bacteriological positivity were compared across the three phases. Results A total of 789 patients were included (pre-pandemic: n = 341; pandemic: n = 270; post-pandemic: n = 178). Compared with the pre-pandemic period, both the pandemic (adjusted OR [aOR] 0.48, 95% CI 0.34–0.68, p < 0.001) and post-pandemic periods (aOR 0.36, 95% CI 0.24–0.53, p < 0.001) were independently associated with reduced odds of diagnostic delay. Conversely, the post-pandemic period was independently associated with higher odds of smear positivity (aOR 1.92, 95% CI 1.28–2.87, p = 0.002), without a corresponding increase in cavitary lesion prevalence. Incidental diagnosis was independently associated with increased diagnostic delay (aOR 2.14, 95% CI 1.40–3.28, p < 0.001). Conclusions The COVID-19 pandemic was associated with a paradoxical pattern in pulmonary TB detection with progressive improvement in diagnostic efficiency alongside a post-pandemic shift toward higher bacteriological positivity, consistent with a pandemic-driven case-mix change rather than a uniform increase in disease severity. Sustaining expanded diagnostic capacity and ensuring equitable healthcare access remain critical priorities for TB control during public health emergencies.

Source: BMC Public Health

DOI: 10.1186/s12889-026-28994-7

Authors: Chia-Ju Hsieh, Tzu-Ping Weng, Mei-Yun Lu, Chung-Lan Lu, Nan-Yao Lee

Institutions: Cardinal Tien College of Healthcare and Management, National Cheng Kung University Hospital, National Cheng Kung University

Language: English

Topic: Tuberculosis Research and Epidemiology

Subfield: Infectious Diseases

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $3,290