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, 68 days into the 90-day surveillance period, a new confirmed case of EVD was reported 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.
With guidance from WHO and other partners, ministries of health in Guinea, Liberia, and Sierra Leone have plans to deliver a package of essential services to safeguard the health of the estimated more than 10 000 survivors of EVD, and enable those individuals to take any necessary precautions to prevent infection of their close contacts. Over 300 male survivors in Liberia have accessed semen screening and counselling services. In addition, over 2600 survivors in Sierra Leone have accessed a general health assessment and eye exam.
To achieve the second key phase 3 response framework objective of managing residual Ebola risks, WHO has supported the implementation of enhanced surveillance systems in Guinea, Liberia, and Sierra Leone to enable health workers and members of the public to report any case of febrile illness or death that they suspect may be related to EVD. In the week to 14 February, 1251 alerts were reported in Guinea from all of the country’s 34 prefectures. The vast majority of alerts (1241) were reports of community deaths. Over the same period, 9 operational laboratories in Guinea tested a total of 316 new and repeat samples (18 samples from live patients and 298 from community deaths) from 17 of the country’s 34 prefectures. In Liberia, 877 alerts were reported from all of the country’s 15 counties, most of which (719) were related to live patients. The country’s 5 operational laboratories tested 924 new and repeat samples (789 from live patients and 135 from community deaths) for Ebola virus over the same period. In Sierra Leone 1872 alerts were reported from the country’s 14 districts. The majority of alerts (1500) were for community deaths. 978 new and repeat samples (37 from live patients and 941 from community deaths) were tested for Ebola virus by the country’s 7 operational laboratories over the same period.
The deployment of rapid-response teams following the detection of a new confirmed case continues to be a cornerstone of the national response strategy in Guinea, Liberia, and Sierra Leone. Each country has at least 1 national rapid-response team, with strengthening of national and subnational rapid-response capacity and validation of incident-response plans continuing throughout 2016.