Ebola Situation Report – 15 July 2015
Ebola Situation Report – 15 July 2015
• There were 30 confirmed cases of Ebola virus disease (EVD) reported in the week to 12 July:
13 in Guinea, 3 in Liberia, and 14 in Sierra Leone. Although the total number of confirmed cases is the same as the previous week, there has been a shift in the foci of transmission. For the first time in several months, most cases were reported from Conakry and Freetown, the capitals of Guinea and Sierra Leone, respectively. All 9 of the cases reported from Conakry and all 10 of the cases reported from Freetown were either registered contacts of a previous case or have an established epidemiological link to a known chain of transmission. One of the 30 cases reported in the week to 12 July arose from a yet unknown source of infection. However, a substantial proportion of cases (7 of 30: 23%) continue to be identified as EVD-positive only after post-mortem testing. This suggests that although improvements to case investigation are increasing our understanding of chains of transmission, contact tracing, which aims to minimise transmission by identifying symptoms among contacts at the earliest stage of infection, is still a challenge in several areas.
• In Guinea, cases were reported from the prefectures of Conakry, Forecariah, and Fria. The northern prefecture of Boke, which has been a focus of transmission for over a month, has not reported a case for 11 days. Nine cases were reported from Conakry, 7 of which are linked to a chain of transmission in the Ratoma area. Three cases, one of whom is a health worker, were reported from Forecariah. The source of exposure of the health worker is under investigation. The remaining case in Guinea was reported from the prefecture of Fria, which had not reported a case for over 40 days. The case is a contact from Boke who had been lost to follow-up.
• Three new cases were reported from Liberia in the week to 12 July, taking the total number of cases since 29 June to 6. The country had not previously reported a case since 20 March. All 3 confirmed cases reported in the week to 12 July were registered contacts associated with the same chain of transmission as the 3 cases reported the previous week. One of the cases reported in the week to 12 July had symptom onset in a quarantined home in Montserrado County, near to the capital, Monrovia, before being transferred to an Ebola Treatment Centre. The origin of the cluster of cases remains under investigation. Preliminary evidence from genomic sequencing strongly suggests that the most likely origin of transmission is a re-emergence of the virus from a survivor within Liberia.
• In Sierra Leone, 14 cases were reported from Freetown, Kambia, and Port Loko. Of the 10 cases reported from Freetown, 8 came from quarantined homes in the Magazine Wharf area of the city, which has been a focus of transmission for several weeks. The remaining 2 cases from Freetown were reported from other areas of the city but are associated with the Magazine Wharf chain of transmission. Two chiefdoms in Kambia reported cases this week, compared with 4 the previous week. Two cases were reported from the northwestern chiefdom of Samu, one of which was a community death. The remaining case from Kambia was reported from Tonko Limba chiefdom. In Port Loko, a single case was reported from the chiefdom of Marampa.
• On 12 July there were 3552 contacts being monitored across 6 prefectures in Guinea, 2 counties in Liberia, and 3 districts in Sierra Leone.
• One new health worker infection was reported from Forecariah, Guinea, in the week to 12 July. There have been a total of 876 confirmed health worker infections reported from Guinea, Liberia, and Sierra Leone since the start of the outbreak, with 509 reported deaths.
COUNTRIES WITH WIDESPREAD AND INTENSE TRANSMISSION
• There have been a total of 27 642 reported confirmed, probable, and suspected cases of EVD in Guinea, Liberia and Sierra Leone (figure 1, table 1) up to 12 July, with 11 261 reported deaths (this total includes reported deaths among probable and suspected cases, although outcomes for many cases are unknown). A total of 13 new confirmed cases were reported in Guinea, 3 in Liberia, and 14 in Sierra Leone in the week to 12 July.
• 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.
• One new health worker infection was reported in Forecariah, Guinea, in the week to 12 July. Since the start of the outbreak a total of 876 confirmed health worker infections have been reported in Guinea, Liberia, and Sierra Leone; there have been 509 reported deaths (table 5).