Interruption of tuberculosis detection and care during the Ebola virus disease epidemic (2014-2015) in Liberia: time-series analyses for 2013-2017

Abstract

Objective: Interrupted time-series analyses, using 5 years of routinely collected health information system data, were conducted to estimate the magnitude of impact of the 2014-2015 Ebola virus disease (EVD) epidemic and determine trends in tuberculosis (TB) care services in Liberia.

Methods: A segmented linear regression model was used to generate estimates and predictions for trends for three TB service indicators before, during, and after EVD, from January 2013 to December 2017.

Results: It was found that the number of presumptive TB cases declined significantly at the start of the EVD outbreak, with an estimated loss of 3222 cases (95% confidence interval (CI) -5691 to -752; P = 0.014). There was also an estimated loss of 709 cases per quarter post-EVD (95% CI -1346 to -71; P = 0.032). However, over the post-EVD period, quarterly increases were observed in the proportion of smear-positive to presumptive cases (1.45%, 95% CI 0.38% to 2.5%; P = 0.011) and the proportion of treatment success to TB cases evaluated (3.3%, 95% CI 0.82% to 5.79%; P = 0.013).

Conclusions: These findings suggest that the EVD outbreak (2014-2015) negatively affected TB care services. Rigorous quantitative analyses can be used to assess the magnitude of interruption and advocate for preparedness in settings with limited healthcare capacity.

Keywords: Case detection; Delivery of health care; Disease outbreaks; Ebola; Epidemics; Interrupted time-series analysis; Liberia; Mycobacterium tuberculosis; Primary health care; Public health; Treatment outcome; Tuberculosis.