Impact of the COVID-19 pandemic on laboratory diagnosis of tuberculosis in southern Brazil

Background and objectives: to understand the impact of the COVID-19 pandemic on tuberculosis (TB) diagnosis in different settings is essential to guide the establishment of appropriate TB control strategies. This study aimed to assess the influence of COVID-19 pandemic in laboratory diagnosis of TB in patients tested and diagnosed for TB. Methods: a data survey was carried out in the database of laboratories that perform TB diagnosis for the public health system in Rio Grande city (Rio Grande do Sul, Brazil). Results: there was a decrease of 1,368 to 735 (reduction of 46.3%) in the number of patients tested for TB in public diagnostic services in 2019 and 2020, respectively, and a decrease of 197 to 119 (reduction of 39.6%) in the number of new TB cases diagnosed. In contrast, the positivity rate was 14.4% in 2019 and 16.2% in 2020. Moreover, it was observed that the laboratory that performs the diagnostic service for Primary Health Care was the most affected, when compared to Tertiary Health Care. Conclusion: as a consequence of measures to control the spread of SARS-CoV-2, there was a reduction in TB testing and in the detection of new cases, especially in Primary Health Care, where patients with less need for hospitalization are received.