Page 1 - Ebola Virus

Early Release / Vol. 63 Morbidity and Mortality Weekly Report
November 14, 2014

Evidence for a Decrease in Transmission of Ebola Virus — Lofa County, Liberia,
June 8–November 1, 2014

Aditya Sharma, MD1, Nico Heijenberg, MD2, Clement Peter, MD3, Josephus Bolongei, MD4, Bruce Reeder, MD5,6, Tamba Alpha4, Esther Sterk, MD5,
Hugues Robert5, Andreas Kurth, PhD7,8, Angela Cannas, PhD7,9, Anne Bocquin, MSc7,10, Thomas Strecker, PhD7,11, Christopher Logue, PhD7,12,
Antonino Di Caro, MD7,9, Thomas Pottage7,12, Constanze Yue, PhD7,8, Kilian Stoecker, PhD7,13, Roman Wölfel, MD7,13, Martin Gabriel, MD7,14,
Stephan Günther, MD7,14, Inger Damon, MD PhD15 (Author affiliations at end of text)

Lofa County has one of the highest cumulative incidences changes in local practices of caring for the ill and burying
of Ebola virus disease (Ebola) in Liberia. Recent situation the dead, 2) developing a dedicated ETU in Foya that could
reports from the Liberian Ministry of Health and Social Welfare efficiently accommodate increases in new admissions, 3) estab-
(MoHSW) have indicated a decrease in new cases of Ebola in lishing a local hotline and outreach teams from Médecins Sans
Lofa County (1). In October 2014, the Liberian MoHSW Frontières (MSF) and local health offices to rapidly transport
requested the assistance of CDC to further characterize persons with Ebola-like symptoms to the Foya ETU and safely
recent trends in Ebola in Lofa County. Data collected during bury persons suspected of dying from Ebola, 4) establishing
June 8–November 1, 2014 from three sources were analyzed: a dedicated laboratory facility for rapid case identification,
1) aggregate data for newly reported cases, 2) case-based data 5) active case-finding in areas with newly reported cases, and
for persons admitted to the dedicated Ebola treatment unit 6) training general community health volunteers to conduct
(ETU) for the county, and 3) test results for community contact tracing of persons with known exposures. No cases
decedents evaluated for Ebola. Trends from all three sources were reported in the county during April 9–May 31, but cases
suggest that transmission of Ebola virus decreased as early as reappeared in early June (5). The intensity and thoroughness
August 17, 2014, following rapid scale-up of response activities of activities increased in response to the resurgence in Ebola.
in Lofa County after a resurgence of Ebola in early June 2014.
The comprehensive response strategy developed with partici- In September 2014, national situation reports suggested a
pation from the local population in Lofa County might serve decrease in new cases of Ebola in Lofa County. In early October,
as a model to implement in other affected areas to accelerate MoHSW asked CDC to further characterize trends in Ebola
control of Ebola. in the county. The following data from June 8 to November 1,
2014, were reviewed: 1) aggregate data for newly reported
Liberia is in the midst of the largest outbreak of Ebola to suspected, probable, and confirmed cases of Ebola; 2) case-
date, with approximately 6,500 reported cases as of October 31, based data for persons admitted to the Foya ETU operated
2014 (2). MoHSW reported 623 cases in an estimated popula- by MSF; and 3) test results for oral swab specimens collected
tion of 300,000 in Lofa County by the end of October, the from persons who died in the community and whose deaths
third highest cumulative incidence in Liberia (3).The first cases were investigated for possible Ebola.
of Ebola in Liberia were reported in March 2014 in Foya (4),
a town of approximately 20,000 persons in Lofa County in Aggregate data for newly reported cases were obtained from
northern Liberia. After the emergence of Ebola in the county, the county health office and publicly available national situation
local government health offices, nongovernmental organiza- reports published by Liberian MoHSW. These data include new
tions, and technical agencies developed a comprehensive cases reported daily by local health offices in the six districts
response strategy in collaboration with communities. The of Lofa County. The weekly number of new cases increased
strategy consisted of the following activities: 1) encouraging from 12 in the week ending June 14 to 153 in the week ending
August 16, and then decreased, reaching four new reported cases
in the week ending November 1 (Figure 1).

U.S. Department of Health and Human Services
Centers for Disease Control and Prevention