Impact of the Ebola virus disease outbreak (2014-2016) on Tuberculosis Surveillance Activities in Guinea's National Tuberculosis Program: A Time Series Analysis

Abstract Background Tuberculosis (TB) is a major cause of disease and death worldwide. According to estimates published by WHO, Guinea is one of the countries with a high incidence of tuberculosis and tuberculosis / HIV co-infection. In March 2014, the World Health Organization (WHO) announced the Ebola virus disease outbreak in Guinea that caused a health system disruption. Our study aimed to assess the impact of the Ebola virus disease outbreak on the TB surveillance system through the main indicators of TB-related morbidity and mortality.Methods This is a retrospective cohort study by comparing TB trends through TB surveillance data from periods before (2011-2013), during (2014-2015) and after (2016-2018) the Ebola virus disease outbreak. A time-series analysis was conducted to investigate the link between the decrease in TB incidence and the Ebola virus disease through cross-correlation. We evaluated the surveillance system to compare its current status with that of the Ebola virus disease outbreak period.Results The reporting rate for TB cases has decreased from 120 cases per 100,000 people reported in 2011 to 100 cases in 2014. The cross-correlation test between TB and the Ebola virus disease incidents shows a significant lag of -0.6 (60%) this corresponds to the drop in TB incidence observed when Ebola virus disease was at its peak in 2014. Concerning the surveillance system, of the 13 standards, only five are reached in 2019 compared to 3 in 2015.Conclusion The Ebola virus disease outbreak has had a severe impact on TB surveillance in Guinea. The introduction of an early warning system would preserve the TB surveillance system; which could encourage the implementation of set stakes to ensure access to diagnosis, treatment for enhanced surveillance of tuberculosis.