Total confirmed cases (by week, 2015)

SUMMARY

There were 2 confirmed cases of Ebola virus disease (EVD) reported in the week to 6 September: 1 in Guinea and 1 in Sierra Leone. Overall case incidence has remained stable at 2 or 3 confirmed cases per week for 6 consecutive weeks. There are a total of three active chains of transmission—two in and around Conakry, Guinea, and one in the western district of Kambia, Sierra Leone—after all remaining contacts associated with transmission chains in Forecariah, Guinea, completed follow-up in the week to 6 September. In addition, Liberia was declared free of Ebola virus transmission in the human population for a second time on 3 September 2015, 42 days after the country’s last laboratory-confirmed case associated with the Margibi cluster of cases completed treatment and was confirmed as EVD-negative. Liberia has now entered a 90-day period of heightened surveillance. The total number of contacts under observation in Guinea and Sierra Leone has increased from approximately 450 on 30 August to approximately 1300 on 6 September. This increase is largely attributable to the single high-risk community death reported from Kambia, Sierra Leone, at the end of the previous week (week to 30 August). Both cases reported in the week to 6 September were registered contacts associated with previous cases in the same areas of Conakry, Guinea, and Kambia, Sierra Leone, in the past 2 weeks. The case reported from Guinea is considered to present a high risk of further transmission. There remains a risk of short-term increases in case incidence as a result of these high-risk cases.

The single confirmed case reported from Guinea in the week to 6 September had onset of symptoms in the Ratoma area of the capital, Conakry. The case is a 13-year-old girl, and is a registered contact and relative of 2 cases reported from the same area of the city during the previous 2 weeks. She is considered to present a high risk of further transmission after she was briefly lost to follow-up after developing early symptoms. She then presented to several private health facilities whilst symptomatic before being traced, tested for EVD and admitted to an Ebola treatment centre. The 292 contacts under follow-up on 6 September in Guinea were located in 2 adjacent prefectures, Conakry (266 contacts) and Dubreka (26 contacts). The last remaining contacts in the prefecture of Forecariah completed follow-up in the week to 6 September.

One new confirmed case was reported from Sierra Leone in the week to 6 September. The case is the daughter of the high-risk case reported from Kambia in the previous week (week to August 30): an approximately 60-year-old woman identified as EVD-positive after post-mortem testing in the village of Sella Kafta, Tonko Limba chiefdom. The most recent case was identified as a high-risk contact after caring for her mother during the course of her mother’s illness. Over 900 contacts have been identified in association with the chain of transmission, although the majority of these contacts have been defined by geographical proximity rather than by history of possible exposure, and are therefore considered to be at very low risk. However, further cases are expected among the approximately 40 high-risk contacts identified so far. The origin of infection of the 60-year-old woman remains under investigation.

No new health worker infections were reported in the week to 6 September. There have been a total of 881 confirmed health worker infections reported from Guinea, Liberia, and Sierra Leone since the start of the outbreak, with 513 reported deaths.

COUNTRIES WITH WIDESPREAD AND INTENSE TRANSMISSION

There have been a total of 28 141 reported confirmed, probable, and suspected cases of EVD in Guinea, Liberia, and Sierra Leone (figure 1, table 1) up to 6 September, with 11 291 reported deaths (this total includes reported deaths among probable and suspected cases, although outcomes for many cases are unknown). One new confirmed case was reported in Guinea and one in Sierra Leone in the week to 6 September.

The total number of confirmed cases is similar in males and females (table 2). Compared with children (people aged 14 years and under), adults aged 15 to 44 are approximately four times more likely to be affected in Guinea and Liberia, and three times more likely to be affected in Sierra Leone.

No new health worker infections were reported in the week to 6 September. Since the start of the outbreak a total of 881 confirmed health worker infections have been reported in Guinea, Liberia, and Sierra Leone; there have been 513 reported deaths (table 5).

Figure 1: Confirmed, probable, and suspected EVD cases worldwide

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Table 1: Confirmed, probable, and suspected EVD cases in Guinea, Liberia, and Sierra Leone

Country Case definition Cumulative cases Cases in past 21 days Cumulative deaths Guinea Confirmed 3338 6 2078 Probable 452 * 452 Suspected 2 * ‡ Total 3792 6 2530 Liberia§ Confirmed 3151 - ‡ Probable 1879 - ‡ Suspected 5636 - ‡ Total 10 666 - 4806 Liberia** Confirmed 6 0 2 Probable * * ‡ Suspected ‡ * ‡ Total 6 0 2 Sierra Leone Confirmed 8699 2 3587 Probable 287 * 208 Suspected 4697 * 158 Total 13 683 2 3953 Total Confirmed 15 194 8 ‡ Probable 2618 * ‡ Suspected 10 335 * ‡ Total 28 147 8 11 291

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Table 2: Cumulative number of confirmed cases by sex and age group in Guinea, Liberia, and Sierra Leone

Country Cumulative cases By sex*

(per 100 000 population) By age group‡

(per 100 000 population) Male Female 0-14 years 15-44 years 45+ years Guinea 1594

(29) 1739

(32) 531

(11) 1898

(41) 860

(55) Liberia§ 1911

(96) 1838

(93) 561

(33) 2060

(121) 703

(132) Sierra Leone 4813

(169) 5102

(176) 1989

(82) 5616

(217) 2138

(289)

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Figure 2: Geographical distribution of confirmed cases reported in the week to 6 September 2015

Table 3: Cases and contacts by district/prefecture/county over the past 3 weeks

Data are based on official information reported by ministries of health. These numbers are subject to change due to ongoing reclassification, retrospective investigation and availability of laboratory results. *Data as of 6 September 2015 for Guinea and Sierra Leone.

Table 4: Location and epidemiological status of confirmed cases reported in the 3 weeks to 6 September 2015

Sub-prefectures/chiefdoms/districts that reported one or more confirmed cases in the 7 days to 6 September are highlighted. *Epi-link refers to cases who were not registered as contacts of a previous case (possibly because they refused to cooperate or were untraceable), but who, after further epidemiological investigation, were found to have had contact with a previous case, OR refers to cases who are resident or are from a community with active transmission in the past 21 days. ‡Includes cases under epidemiological investigation. §A case that is identified as a community death can also be registered as a contact, or subsequently be found to have had contact with a known case (epi-link), or have no known link to a previous case.

Figure 3: Geographical distribution of new and total confirmed cases in Guinea, Liberia, and Sierra Leone

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Table 5: Ebola virus disease infections in health workers in Guinea, Liberia and Sierra Leone

Country Cases Deaths Guinea 196 100 Liberia* 378 192 Sierra Leone 307 221‡ Total 881 513

GUINEA

Key performance indicators for the EVD response in Guinea are shown in table 6.

One confirmed case was reported from the Ratoma area of Conakry in the week to 6 September (table 3, table 4, figure 2, figure 3).

The case is a 13-year-old girl, and is a registered contact and relative of 2 cases reported from the same area of Conakry during the previous 2 weeks. She is considered to present a high risk of further transmission after she was briefly lost to follow-up and presented to several private health facilities whilst symptomatic before being traced, tested for EVD and admitted to an Ebola treatment centre.

The Ebola ça suffit! ring vaccination trial is continuing in Guinea. All rings comprised of contacts and contacts of contacts associated with confirmed cases now receive immediate vaccination with the rVSV-ZEBOV Ebola vaccine. Previously, rings were randomly allocated to receive either immediate vaccination or vaccination 21 days after the confirmation of a case.

292 contacts were under follow-up on 6 September in Guinea in 2 adjacent prefectures, Conakry (266 contacts) and Dubreka (26 contacts), compared with 410 contacts in 3 prefectures the previous week. The last remaining contacts in Forecariah completed follow-up in the week to 6 September.

There were 9 (2%) unsafe burials reported in Guinea out of 542 community deaths in the week to 6 September, compared with 5 (0.9%) unsafe burial out of 568 recorded community deaths in the previous week.

Including both initial and repeat testing, a total of 752 laboratory samples were tested in the week to 6 September. Most tests (92% in the week to 6 September) are of post-mortem swabs taken to rule out EVD as the cause of death.

Locations of the 8 operational Ebola treatment centres (ETCs) are shown in figure 7. No health worker infections were reported in the week to 30 August.

Locations of the 9 operational laboratories in Guinea are shown in figure 8.

Table 6: Key performance indicators for Guinea

For definitions of key performance indicators see Annex 2. Data are given for 7-day periods. *Includes repeat samples. ‡Data missing for 0–3% of cases. #Outcome data missing for 0–1% of hospitalized confirmed cases.

Figure 4: Confirmed weekly Ebola virus disease cases reported nationally and by prefecture from Guinea

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SIERRA LEONE

Key performance indicators for the EVD response in Sierra Leone are shown in table 7.

One new confirmed case was reported from Sierra Leone in the week to 6 September (table 3, table 4, figure 2, figure 3). The case is the daughter of the high-risk case reported from Kambia in the week to August 30: an approximately 60-year-old woman identified as EVD-positive after post-mortem testing in the village of Sella Kafta, Tonko Limba chiefdom. The most recent case was identified as a high-risk contact after caring for her mother during the course of her mother’s illness. Further cases are expected among the approximately 40 high-risk contacts identified in association with the chain of transmission. The origin of infection of the 60-year-old woman remains under investigation.

The Ebola ça suffit! ring vaccination Phase 3 efficacy trial of the rVSV-ZEBOV vaccine has now been extended from Guinea to Sierra Leone. Contacts and contacts of contacts associated with new confirmed cases and who meet the trial’s eligibility criteria will therefore be offered the vaccine.

As at 6 September a total of 989 contacts had been identified in Kambia in association with the case reported in the week to 30 August, although the majority of these contacts have been defined by geographical proximity rather than by history of exposure, and are therefore considered to be at very low risk. Approximately 40 contacts are considered to be high risk. All contacts associated with other chains of transmission in Sierra Leone have completed 21-day follow-up.

Locations of the 10 operational Ebola treatment centres (ETCs) in Sierra Leone are shown in figure 7. No health worker infections were reported in the week to 6 September.

Laboratory indicators continue to reflect a heightened degree of vigilance, with 1862 new samples tested in the week to 6 September. One new sample tested positive for EVD. Most tests (77% in the week to 6 September) are of post-mortem swabs taken to rule out EVD as the cause of death.

Locations of the 8 operational laboratories in Sierra Leone are shown in figure 8.

Table 7: Key performance indicators for Sierra Leone

For definitions of key performance indicators see Annex 2. Data are for 7-day periods. §Laboratory data missing for 14 July. ‡Data missing for 7–14% of cases. #Outcome data missing for 0–77% of hospitalized confirmed cases.

Figure 5: Confirmed weekly Ebola virus disease cases reported nationally and by district from Sierra Leone

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Figure 6: Days since last confirmed case by district in Guinea, Liberia, and Sierra Leone

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OTHER AFFECTED AND PREVIOUSLY AFFECTED COUNTRIES

Liberia was declared free of Ebola virus transmission in the human population on 3 September 2015, 42 days after the country’s last laboratory-confirmed case completed treatment and was confirmed as EVD-negative. It is now 56 days since symptom onset of the last reported confirmed case (figure 6). The country has now entered a 90-day period of heightened surveillance. Laboratory capacity is being increased to speed up the processing of samples.

Seven countries (Italy, Mali, Nigeria, Senegal, Spain, the United Kingdom, and the United States of America) have previously reported a case or cases imported from a country with widespread and intense transmission.

Figure 7: Location of Ebola treatment centres in Guinea, Liberia, and Sierra Leone

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PREPAREDNESS OF COUNTRIES TO RAPIDLY DETECT AND RESPOND TO AN EBOLA EXPOSURE

The introduction of an EVD case into unaffected countries remains a risk as long as cases exist in any country. With adequate preparation, however, such an introduction can be contained through a timely and effective response.

WHO’s preparedness activities aim to ensure all countries are ready to effectively and safely detect, investigate, and report potential EVD cases, and to mount an effective response. WHO provides this support through country support visits by preparedness-strengthening teams (PSTs) to help identify and prioritize gaps and needs, direct technical assistance, and provide technical guidance and tools.

Figure 8: Location of laboratories in Guinea, Liberia, and Sierra Leone

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Priority countries in Africa

The initial focus of support by WHO and partners is on highest priority countries – Côte d’Ivoire, Guinea-Bissau, Mali, and Senegal—followed by high priority countries—Benin, Burkina Faso, Cameroon, Central African Republic, Democratic Republic of the Congo, Ethiopia, Gambia, Ghana, Mauritania, Niger, Nigeria, South Sudan, and Togo. The criteria used to prioritize countries include the geographical proximity to affected countries, the magnitude of trade and migration links, and the relative strength of their health systems.

Since 20 October 2014, PSTs have provided technical support in Benin, Burkina Faso, Cameroon, Central African Republic, Côte d’Ivoire, Ethiopia, Gambia, Ghana, Guinea-Bissau, Mali, Mauritania, Niger, Senegal, South Sudan, and Togo. Technical working group meetings, field visits, high-level table-top exercises, and field simulations have helped to identify key areas for improvement. Each country has a tailored plan to strengthen operational readiness.

From October 2014 to August 2015 WHO has undertaken over 285 field deployments to priority countries to assist with the implementation of national plans.

WHO provides personal protective equipment (PPE) modules containing minimum stocks to cover staff protection and other equipment needs to support 10 patient-beds for 10 days for all staff with essential functions. PPE modules have been delivered or are in the process of being delivered to all countries on the African continent. In addition, all countries have received 1 PPE training module.

Contingency stockpiles of PPE are in place in the United Nations Humanitarian Response Depots (UNHRD) in Accra and Dubai, and are available to any country in the event that they experience a shortage.

Follow-up support to priority countries

Following initial PST assessment missions to the 14 priority countries in 2014, a second phase of preparedness-strengthening activities have provided support on a country-by-country basis. Activities in the week to 9 September are highlighted below.

In Guinea Bissau, preparedness support continues to be provided at the central level, and in two priority regions (Tombali and Gabu) through WHO sub-offices.

EVD preparedness officers

Dedicated EVD preparedness officers have been deployed to support the implementation of country preparedness plans, coordinate partners, provide a focal point for inter-agency collaboration, offer specific technical support in their respective areas of expertise, and develop capacity of national WHO staff. Preparedness officers are currently deployed to Benin, Cameroon, Central African Republic, Côte d’Ivoire, Ethiopia, Gambia, Ghana, Guinea-Bissau, Mali, Mauritania, Niger, Senegal, and Togo.

Training, exercises, and simulations

Priority countries that have achieved a minimum of 50% implementation of preparedness checklist activities are encouraged to undertake a series of drills on elements of an EVD response and a functional exercise to test the coordination of the Ebola operations centre.

Simulation exercises aimed at testing preparedness capabilities are being planned in Benin, Burkina Faso, Ethiopia, Ghana, Guinea Bissau, and Mauritania, and will start in the coming weeks.

An infection prevention and control (IPC) specialist will be deployed to Togo at the beginning of October to follow-up on activities performed during a previous visit to the country.

Training in public health functions at points-of-entry is planned for the end of September in Mauritania.

Training in clinical management and IPC will be take place from 21 September to 4 October in Côte d’Ivoire.

Surveillance and preparedness indicators

Indicators based on surveillance data, case-management capacity, laboratory testing, and equipment stocks continue to be collected on a weekly basis from the four countries that share a border with affected countries: Côte d’Ivoire, Guinea-Bissau, Mali, and Senegal.

An interactive preparedness dashboard based on the WHO EVD checklist is now available online.

ANNEX 1: COORDINATION OF THE EBOLA RESPONSE ALONG 4 LINES OF ACTION

WHO continues to work with many partners in response to the EVD outbreak, including the African Union, the Economic Community of West African States, the Mano River Union, national governments, non-governmental organizations, and UN agencies, and technical institutions and networks in the Global Outbreak Alert and Response Network (GOARN). Agencies responsible for coordinating 4 key lines of action in the response are given below.

Lines of action Lead agency Case management WHO Case finding, laboratory services and contact tracing WHO Safe and dignified burials International Federation of Red Cross and Red Crescent Societies (IFRC) Community engagement and social mobilization UNICEF

ANNEX 2: DEFINITIONS OF PHASE 2 KEY PERFORMANCE INDICATORS