How has the municipal availability of the GeneXpert®MTB/RIF system affected the detection of drug-resistant tuberculosis in Brazil?

Abstract

Objective: To evaluate the association between the availability of GeneXpert®MTB/RIF in municipalities and the proportion of people who have access to this diagnostic technology for tuberculosis (TB), as well as the resistance detected by the surveillance system in Brazil.

Methods: We analysed 4998 Brazilian municipalities that reported 432,937 new TB cases between 2015 and 2020. We compared municipalities with and without the availability of GeneXpert®MTB/RIF regarding the effective access to GeneXpert®MTB/RIF diagnosis and the prevalence of detected resistance.

Results: Municipalities with at least one GeneXpert®MTB/RIF system had three times (95% CI 2.9-3.0) the access to diagnostic tests and 80.4% (95% CI 70.6%-90.2%) higher detection of resistance, compared with municipalities without this technology. We estimated that there have been 1890 cases of undetected resistance during this period in the country.

Conclusions: The availability of GeneXpert®MTB/RIF system in the municipality increased the sensitivity of the surveillance for detecting TB resistance.

Public health implications: It is a priority to strengthen laboratory networks and narrow the gap in access to rapid diagnosis in remote areas to improve the detection and control of drug-resistant tuberculosis.

Keywords: GeneXpert MTB/RIF; access; drug resistance; rapid diagnosis; tuberculosis.