Case-fatality Ratio Due to Ebola Virus Disease in North-eastern Democratic Republic of the Congo in 2019

During an Ebola virus disease (EVD) outbreak, health workers (HWs) are at high risk of EVD infection. Health workers infected with EVD are a major risk factor for the failure to control EVD outbreaks. The tenth outbreak is the largest recorded in the DRC, but unfortunately few studies have described the occurrence, case-fatality ratio (CFR) among HWs and their perceptions. The aim of this study was to describe: the occurrence of EVD; related mortality; and perceptions of EVD transmission among HWs. A mixed methods study was conducted in north-eastern DRC in August 2019. A review of EVD surveillance data and in depth interviews with 16 front line HWs were carried out. Interviews were audio recorded and transcribed verbatim in Swahili before being translated into French and subsequently into English. Quantitative data were imported from Microsoft Excel to Stata 14.0 for analysis. Mean and standard deviation (SD) were used to summarize numeric variables while frequency was used for categorical data. All descriptive statistics are reported with their 95% confidence interval. From 12 July 2018 to 17 August 2019, some 151 confirmed and three probable health worker cases were recorded in the viral haemorrhagic fever (VHF) surveillance dataset for the provinces of North-Kivu and Ituri. Heath workers accounted for 5.5% [4.6-6.4]. More than half of the HWs infected were male, with a male to female ratio of 1.3. The mean age of HWs infected was 33.9 years (sd: 10.3). Nosocomial transmission was the most common route of transmission among HWs (94.1%). For more than a quarter of the HWs the contact case was unknown. From a total of 154 infected HWs, some 29 died (CFR: 18.8% [13.0-25.9]). The factors mentioned by HWs as being associated with EVD transmission among them were: ignorance that patient was infected; unavailability of protective equipment; non-compliance of hygienic measures like regular hand washing; violation of EVD infection prevention and control (IPC) standards; and their resistance thereto. The occurrence of EVD cases among HWs is a challenge for the control of the current outbreak in the DRC. It is important to implement strategies to reduce transmission in this population group.