Two more Ebola infections have been confirmed in Liberia, putting the number of recent cases at 5, as the outbreak region reported its highest weekly total since the middle of May—30—which the World Health Organization (WHO) said overshadows new gains in contact tracing and case reporting.
Health officials still haven't determined the source that triggered the spurt of cases in Liberia, which, until a 17-year-old boy's fatal infection in late June, hadn't reported a case in 3 months.
The total in the three outbreak countries has reached 27,573 confirmed, probable, and suspected Ebola cases, including 11,246 deaths, the WHO said today in its weekly epidemiologic report on the outbreak.
Questions surround Liberia cluster
Francis Ketteh, deputy head of Liberia's Ebola response team, said tests have confirmed 2 new Ebola infections, on top of 3 previously announced cases, Reuters reported today. A second response team member told the news organization that the case total in the new outbreak is at 5.
The new cases aren't reflected in today's WHO update, but it said in addition to the three earlier cases, a probable case-patient has been isolated at an Ebola treatment center. It added that the patient in isolation has a strong epidemiologic link to the first case and has some Ebola symptoms, but test results were indeterminate.
The source of Liberia's new Ebola cluster is under investigation, but currently health officials are considering the outbreak separate from the one that was declared over on May 9, the WHO said.
Rumors have been circulating in Liberia about possible sources of the 17-year-old boy's infection, including that he and possibly others got sick after eating meat from a dead dog. A health official in Liberia told Reuters that tests on samples from the dog's carcass were negative, but cautioned that the samples were in bad condition and that the test authorities used is intended for use on humans only.
Guinea, Sierra Leone hot spots remain
Across all three countries in the outbreak region last week, 30 lab-confirmed cases were reported, the highest weekly total since the middle of May, the WHO said. Besides Liberia's first 3 cases, Guinea reported 18 and Sierra Leone reported 9. However, the agency added that the uptick comes alongside improvements in contact tracing, incentives to improve case reporting, and compliance with quarantine steps.
The factors have led to a better understanding of transmission chains with to a month ago, which is whittling down the number of Ebola infections arising from unknown sources, the WHO said. The agency warned, however, that some affected communities still don't trust responders, which can result in cases evading detection and sparking more unknown transmission chains.
The latest cases in Guinea and Sierra Leone are still coming from the same hot spots, which are mainly in the western parts of each country. Cases in Boke, a district in the northern part of Guinea near the border with Guinea-Bissau, dropped last week from 10 to 6, with all but 1 from a registered contact.
Eleven of Guinea's cases were in Forecariah district, and all but two were from known contacts or had previously links to earlier cases, the WHO said. Only one case was reported in Conakry and involved a known contact.
In Sierra Leone, 3 of the country's 9 Ebola cases were in Freetown's densely populated Magazine Wharf area, and all were known contacts of previous cases. Of 6 cases reported in the hot spot areas of Kambia and Port Loko districts, only 1 was from an unknown transmission chain.
Some cases in the outbreak countries are still being identified only after death in the community, a sign that not all sick patients are being treated and isolated. Guinea had four such cases, and Sierra Leone had three.
Only one new health worker infection was reported last week, in Sierra Leone's Kambia district, raising that total to 875 cases, 509 of them fatal.
Jul 8 WHO Ebola situation update
Jul 8 Reuters story