A total of 99 new confirmed cases of Ebola virus disease (EVD) were reported in the week to 22 Feb 2015, according to a World Health Organization Update.

Public domain image/Mondo Magic
Public domain image/Mondo Magic

Guinea reported 35 new confirmed cases. Cases continue to arise from unknown chains of transmission. Transmission remains widespread in Sierra Leone, with 63 new confirmed cases. A spike of 20 new confirmed cases in Bombali is linked to the previously reported cluster of cases in the Aberdeen fishing community of the capital, Freetown. There were 14 new confirmed cases in Freetown over the same period, with cases still arising from unknown chains of transmission in Freetown and elsewhere. Transmission continues at very low levels in Liberia, with 1 new confirmed case reported in the 7 days to 22 Feb 2015: a registered contact associated with a known chain of transmission in the capital, Monrovia.

Engaging effectively with communities remains a challenge in several geographical areas. Nearly one-third of prefectures in Guinea reported at least one security incident in the week to 22 Feb 2015, often as a result of rumors and misinformation linking response efforts with the spread of EVD.

A total of 16 new confirmed cases were identified in Guinea and Sierra Leone after post-mortem testing of individuals who died in the community, indicating that a significant number of individuals are still either unable or reluctant to seek treatment. Ideally these individuals would have been identified as contacts associated with known chains of transmission, and have been rapidly diagnosed, isolated, and treated after the initial onset of symptoms. In Guinea and Sierra Leone, 19 and 15 unsafe burials were reported, respectively.

Most new cases in Guinea were reported from 3 neighboring western prefectures: Conakry (6 new confirmed cases), Coyah (8 new confirmed cases), and Forecariah (16 confirmed cases). However, the eastern prefecture of Lola, on the border with Cote d’Ivoire, reported 1 new confirmed case. Case incidence has fluctuated in this prefecture. The northern prefecture of Mali, which borders Senegal, also reported 1 new confirmed case.

The steep decline in case incidence nationally in Sierra Leone from December 2014 until the end of January 2015 has halted. Transmission remains widespread, with 8 districts reporting new confirmed cases. A significant proportion of cases are still arising from unknown chains of transmission.

Of laboratories that report results to the relevant ministry of health, between 84 percent and 98 percent of laboratory samples were tested within 1 day of collection in the 22 days to 22 Feb 2015. At present there are no data on how rapidly results are communicated to patients.

In the week to 22 Feb 2015, 3 new health worker infections were reported (2 from Guinea, 1 from Sierra Leone), bringing the total of health worker infections reported since the start of the outbreak to 837, with 490 deaths.

There have been over 23,500 reported confirmed, probable, and suspected cases of EVD in Guinea, Liberia and Sierra Leone, with over 9,500 reported deaths (outcomes for many cases are unknown).