Nuances in the global impact of COVID-19 on tuberculosis control efforts: An updated review.

The COVID-19 pandemic has affected public health systems in an unprecedented manner. There has been an abundance of discussion regarding the possible effects of the pandemic in disruption of health services aiming at tuberculosis (TB) infection control - including hindered screening efforts and delays in diagnosis and treatment. The pandemic has also been proposed to affect TB transmission via lifestyle modifications. Moreover, some research has suggested a more direct link between COVID-19 infection and increased TB morbidity and mortality. The authors conducted a narrative review of the relevant literature. Searches were performed in the MEDLINE, Scopus, and Web of Science databases. Reports of impaired TB case-notification were ubiquitous during the early stages of the pandemic. Subsequently, divergent patterns emerged: recovery and decreased TB incidence in countries with stringent public health measures, low local transmission of TB, and resilient health systems; or devastating results from TB underdiagnosis and delayed treatment in countries with high TB burden, limited COVID-19 control measures, and public health funding. Few studies quantified the effects of TB and COVID-19 co-infection - and the possible role of COVID-19 infection in reactivation of latent tuberculosis infection (LTBI) remains ambiguous. Despite the lapse of the COVID-19 pandemic, its effects on TB control efforts perseverate. Particularly, great care is warranted for recovery of impacted healthcare systems in low-income countries.