Evidence for a decrease in transmission of Ebola virus--Lofa County, Liberia, June 8-November 1, 2014

Area of Science:

• Epidemiology
• Infectious Disease Control
• Public Health

Background:

• Lofa County, Liberia, experienced high Ebola virus disease (EVD) incidence.
• Recent reports indicated a decrease in new EVD cases in Lofa County.
• The Liberian Ministry of Health and Social Welfare (MoHSW) sought CDC assistance to analyze EVD trends.

Purpose of the Study:

• To characterize recent trends in Ebola virus disease transmission in Lofa County, Liberia.
• To evaluate the impact of response activities on EVD transmission.
• To identify potential models for EVD control in affected regions.

Main Methods:

• Analysis of aggregate data for newly reported EVD cases (June 8–November 1, 2014).
• Analysis of case-based data for patients admitted to the Lofa County Ebola Treatment Unit (ETU).
• Analysis of test results for community decedents evaluated for EVD.

Main Results:

• Data from all three sources indicated a decrease in EVD transmission starting around August 17, 2014.
• The decline followed a rapid scale-up of response activities after an early June 2014 resurgence.
• Response activities were implemented with local population participation.

Conclusions:

• Intensified and community-involved response strategies in Lofa County appear to have accelerated EVD control.
• The Lofa County response model may be applicable to other EVD-affected areas.
• Effective public health interventions are crucial for managing EVD outbreaks.