SUMMARY
There were 4 confirmed cases of Ebola virus disease (EVD) reported in the week to 27 September, all in Guinea. Case incidence has remained below 10 cases per week since the end of July this year. Over the same period, transmission of the virus has been geographically confined to several small areas in western Guinea and Sierra Leone, marking a transition to a distinct, third phase of the epidemic. Improvements to case investigation and contact tracing, rapid isolation and treatment, and effective engagement with affected communities have all played a part in reducing case incidence to its current low level. A refined phase-3 response1 coordinated by the Interagency Collaboration on Ebola2 will build on these measures to drive case incidence to zero, and ensure a sustained end to EVD transmission. Enhanced capacity to rapidly identify a reintroduction (either from an area of active transmission or from an animal reservoir), or re-emergence of virus from a survivor, improved testing and counselling capacity as part of a comprehensive package to safeguard the welfare of survivors, and the increased use of innovative technologies—from vaccines to rapid diagnostic tests—are central to the phase-3 response framework.
All 4 confirmed cases reported from Guinea this week had symptom onset in Forecariah, and are registered contacts of a 10-year-old girl who sought treatment in Forecariah after traveling from the Ratoma area of the capital, Conakry. She subsequently died on 14 September in the Forecariah sub-prefecture of Kaliah. Two of the 4 new cases are traditional healers who are reported to have treated the girl. Over 450 contacts are under follow-up in Guinea, including 1 in the prefecture of N’Zerekore due to the movement of a contact associated with the Ratoma chain of transmission. The majority of contacts (311) are located in Forecariah, with 147 in Conakry. All contacts are associated with the Ratoma chain of transmission. From 28 September to 1 October an active case-finding operation is taking place in the Conakry districts of Dixinn and Ratoma during which approximately 900 households will be visited.
No new confirmed cases were reported from Sierra Leone in the week to 27 September: the second consecutive week with zero cases. Over 700 contacts remain under follow-up in Bombali related to the last reported case on 13 September. All contacts associated with the Kambia chain of transmission were scheduled to complete follow-up on 28 September.
Robust surveillance measures are essential to ensure the rapid detection of any reintroduction or reemergence of EVD in currently unaffected areas. A total of 784 samples were tested by 8 operational laboratories in Guinea in the week to 27 September. Analyses of the geographical distribution of samples collected indicate that 18 of 34 Guinean prefectures did not collect any samples from either live or dead suspected cases of EVD over the 1-week period. In Liberia, 1373 samples were collected from 100% (15 of 15) of counties in the week to 27 September. Laboratory capacity in the country has increased following the opening of a laboratory in Montserrado, bringing the total number of operational laboratories in the country to 4. Over the same period, 1969 samples were collected from 100% (14 of 14) of districts in Sierra Leone and tested by 9 operational laboratories. Surveillance in the three countries will be enhanced in line with the phase-3 response framework.