Mortality among confirmed Lassa Fever cases in Ondo State, Nigeria, January 2017- March 2019: A cross sectional study

Lassa fever (LF) is an acute viral haemorrhagic disease endemic in Ondo State, Nigeria. This study aimed to determine the factors associated with mortality among confirmed LF cases.

A cross sectional study design was used by conducting a retrospective review of the records of all patients who had been treated for LF at the Federal Medical Centre, Owo since 2017 till March 2019. Descriptive statistics were done, case fatality rate was calculated. Chi square tests were used to explore associations. Logistic regression was used to identify the predictors of death. Data were analysed with SPSS version 23.0. P values ≤0.05 were statistically significant.

The median age was 34 years, and the inter-quartile range was 24-48 years. A total of 30 deaths (case fatality rate [CFR] = 10.9%) were recorded, of which 24 (15.5%) were males. Also, the fatality rate increased from 1.6% in 2017 to 10.5% in 2018 and 16.7% in 2019. During peak period, mortality recorded was 15(8.5%) and non-peak periods (April to December), 14(14.9%) was recorded (p=0.104). Fatality was 12.5% (1 out of 8) among pregnant women with 100% foetal death. Patients aged 18-45 years had 0.25 odds of dying (AOR = 0.25; 95%CI= 0.08, 0.76) compared to those aged ≥ 46 years. Those who commenced ribavirin ≥7 days (AOR 4.1; CI = 1.06, 15.42) and those with elevated urea level (AOR 7.5; CI = 2.5, 23.1) have more odds of dying.

A well-coordinated LF outbreak response is needed both at LF peak non-peak periods.