Epidemiological update: outbreak of Ebola virus disease in West Africa, 7 August 2014
This is the largest ebola outbreak ever recorded in terms of geographical spread and number of cases and deaths reported. On 8 August, the World Health Organisation declared it a Public Health Emergency of International Concern (PHEIC).
On 8 August, the World Health Organisation declared the outbreak of Ebola virus disease (EVD) evolving in West Africa a Public Health Emergency of International Concern (PHEIC).
The outbreak started in December 2013 and it is currently accelerating. The outbreak is growing in Guinea, Liberia, Sierra Leone and more recently in Nigeria, a newly affected country with locally acquired infections. Transmission has occurred in large cities of these four countries (Conakry, Freetown, Monrovia and Lagos).As of 6 August, the cumulative number of cases reported was 1779, including 961 deaths, making this EVD outbreak by far the largest ever recorded in terms of geographical spread and number of cases and deaths reported. Of these, 815 (46%) cases including 358 deaths were reported in the past four weeks.
On 29 July 2014, WHO was notified of a probable EVD case in Nigeria. The case travelled by air and arrived in Lagos, Nigeria, on 20 July via Lomé, Togo, and Accra, Ghana and was symptomatic at the time of arrival. As of 7 August, medical evacuations of EVD sick patients were performed to USA (two patients) and Spain (one patient).
The distribution of cases by week of reporting since the start of the outbreak is the following:
Weekly number of EVD cases in West Africa (Guinea, Sierra Leone, Liberia and Nigeria) up to 06/08/2014
All countries
Per country
Source: adapted from WHO (Ebola virus disease, West Africa – update)Data for the week 32/2014 are incomplete.
Situation by country as of 6 August (source WHO) Guinea: 495 cases (355 confirmed), including 367 deaths (case-fatality ratio 74%).Liberia: 554 cases (148 confirmed cases), including 294 deaths (case-fatality ratio 53%).Nigeria: 13 cases (0 confirmed, 7 probable, and 6 suspected), including 2 deaths. Sierra Leone: 717 cases (631 confirmed), including 298 deaths (case-fatality ratio 42%).Overview of EVD cases (confirmed, probable and suspected) and deaths in Guinea, Liberia, Sierra Leone and Nigeria, as of 6 August 2014
| Country | Number of cases |
Number of deaths |
CFR* |
Guinea |
495 |
367 |
74% |
Sierra Leone |
717 |
298 |
42% |
Liberia |
554 |
294 |
53% |
Nigeria |
13 |
2 |
15% |
Total |
1779 |
961 |
54% |
*CFR - Case Fatility Ratio
Source: Adapted from WHO (Ebola virus disease, West Africa – update), 8 August
