Comparison of molecular and microbiological detection rates of Mycobacterium tuberculosis and prevalence of SARS-CoV-2 variants in Monterrey, Mexico

Abstract

BackgroundTuberculosis (TB) is a severe global health problem, with high drug resistance rates. The emergence of the coronavirus disease 2019 (COVID-19) pandemic caused worldwide setback progress in TB control. Our aim was to compare detection rates of Mycobacterium tuberculosis at different COVID-19 pandemic waves. MethodsPatients (n = 1800) were evaluated using microbiological and molecular assays for mycobacterial detection in a hospital from Monterrey, Mexico. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was detected by real-time PCR. Data from existing reports of circulating SARS-CoV-2 variants was compared to data of TB prevalence. ResultsThe prevalence of TB was 30.4%. Compared to pre-pandemic, the detection rate of mycobacteria was higher during the first wave. The co-infection of Mycobacterium tuberculosis complex (MTC) and SARS-CoV-2 occurred in seven patients. MTC cases showed several waves which might depend on the prevalence of specific SARS-CoV-2 variants. ConclusionThe COVID-19 pandemic impacted on TB detection on our population, although it is still uncertain if it was mostly due to the influence of specific SARS-CoV-2 variants or to restrictions measures in the region. Public health measures should include the combination of TB and COVID-19 diagnostic screening in TB-endemic settings, such as ours, to restore TB control attempts.