Human-to-human transmission directly linked to the 2014 Ebola virus disease (EVD) outbreak in West Africa was declared to have ended in Sierra Leone on 7 November 2015. The country then entered a 90-day period of enhanced surveillance to ensure the rapid detection of any further cases that might arise as a result of a missed transmission chain, reintroduction from an animal reservoir, importation from an area of active transmission, or re-emergence of virus that had persisted in a survivor. On 14 January 2016, 68 days into the 90-day surveillance period, a new confirmed case of EVD was reported in Sierra Leone after a post-mortem swab collected from a deceased 22-year-old woman tested positive for Ebola virus.
On 20 January, the aunt of the index case developed symptoms and tested positive for Ebola virus. The aunt was in a voluntary quarantine facility at the time she developed symptoms, after previously being identified as a high-risk contact. On 4 February the aunt of the index case provided a second consecutive Ebola-RNA-negative blood sample and was discharged.
All contacts linked to the two cases had completed follow-up by 11 February 2016. Efforts to locate several untraced contacts in the district of Kambia will continue until at least 24 February. If no further cases are detected, transmission linked to this cluster of cases will be declared to have ended on 17 March.
Human-to-human transmission linked to the most recent cluster of cases in Liberia was declared to have ended on 14 January 2016. Guinea was declared free of Ebola transmission on 29 December 2015, and is approximately halfway through a 90-day period of enhanced surveillance that is due to end on 27 March 2016.
Sources:
- WHO, Ebola situation report- 17 February 2016.
http://apps.who.int/ebola/current-situation/ebola-situation-report-17-february-2016