The Public Health Emergency of International Concern (PHEIC) related to Ebola in West Africa was lifted on 29 March 2016. A total of 28 616 confirmed, probable and suspected cases have been reported in Guinea, Liberia and Sierra Leone, with 11 310 deaths.
In the latest cluster, seven confirmed and three probable cases of Ebola virus disease (EVD) were reported between 17 March and 6 April from the prefectures of N’Zerekore (nine cases) and Macenta (one case) in south-eastern Guinea. In addition, three confirmed cases were reported between 1 and 5 April from Monrovia in Liberia; these cases, the wife and two children of the Macenta case, travelled from Macenta to Monrovia.
The index case of this cluster (a 37-year-old female from Koropara sub-prefecture in N’Zerekore) had symptom onset on or around 15 February and died on 27 February without a confirmed diagnosis. The source of her infection is likely to have been due to exposure to infected body fluid from an Ebola survivor.
In Guinea, the last case tested negative for Ebola virus for the second time on 19 April. In Liberia, the last case tested negative for the second time on 28 April. The 42-day (two incubation periods) countdown must elapse before the outbreak can be declared over in Guinea and Liberia. This is due to end on 31 May in Guinea and on 9 June in Liberia.
Having contained the last Ebola virus outbreak in March 2016, Sierra Leone has maintained heightened surveillance with testing of all reported deaths and prompt investigation and testing of all suspected cases. The testing policy will be reviewed on the 30 June.
Risk assessment:
For the outbreak to be declared over, a 42-day countdown must pass after the last case tested negative for Ebola virus for the second time. This countdown is due to elapse on 31 May in Guinea and on 9 June in Liberia. Until then, active surveillance in Guinea and Liberia will continue. The performance indicators suggest that Guinea, Liberia and Sierra Leone still have variable capacity to prevent, detect (epidemiological and laboratory surveillance) and respond to new outbreaks (Table 1). The risk of additional outbreaks originating from exposure to infected survivor body fluids remains and requires sustained mitigation through counselling on safe sex practices and testing of body fluids.