Mortality Among Confirmed Lassa Fever Cases During the 2015-2016 Outbreak in Nigeria

To determine factors associated with mortality among confirmed Lassa fever cases.

We reviewed line lists and clinical records of laboratory-confirmed cases of Lassa fever during the 2016 outbreak in Nigeria to determine factors associated with mortality. We activated an incident command system to coordinate response.

We documented 47 cases, 28 of whom died (case fatality rate [CFR] = 59.6%; mean age 31.4 years; SD = ±18.4 years). The youngest and the oldest were the most likely to die, with 100% mortality in those aged 5 years or younger and those aged 55 years or older. Patients who commenced ribavirin were more likely to survive (odds ratio [OR] = 0.1; 95% confidence interval [CI] = 0.03, 0.50). Fatality rates went from 100% (wave 1) through 69% (wave 2) to 31% (wave 3; χ² for linear trend: P < .01). Patients admitted to a health care center before incident command system activation were more likely to die (OR = 4.4; 95% CI = 1.1, 17.6). The only pregnant patient in the study died postpartum.

Effective, coordinated response reduces mortality from public health events. Attention to vulnerable groups during disasters is essential. Public Health Implications. Activating an incident command system improves the outcome of disasters in resource-constrained settings.