Experts to investigate new Ebola case in north Sierra Leone

Ebola experts are in Sierra Leone's Kambia district investigating a case that emerged less than a week after the country's last known patient was discharged from hospital, a World Health Organization spokeswoman said Monday.

Once the source of transmission is found and contacts are traced, a vaccination trial will also begin in the northern Sierra Leone area, said Dr. Margaret Harris, WHO spokeswoman.

Samples from the body of a 67-year-old woman who died in Kambia recently came back positive for Ebola, authorities said Sunday.

"It's a step back and a disappointment but it wasn't a surprise as it's near the border with Guinea," where cases remain, said Harris. "If you get onto it early and have good surveillance," it can be stopped.

Liberia had a similar situation. A sample from a corpse tested positive in late June after the country had been declared Ebola-free in May. It was quickly contained and Liberia may again declare itself free from Ebola transmissions this week, said Harris.

Authorities decided weeks ago to extend a vaccine trial from Guinea to Sierra Leone, Harris said.

The trial for the VSV-EBOV—developed by Canada and licensed to Merck—is meant to be done where there is Ebola, she said. The strategy is to target contacts of the infected, and contacts of those contacts to create a buffer zone around a case to prevent its spread. Now that there is a case, the trial will begin in Kambia.

Once the source in Kambia is determined, and contacts found, they will seek participants in the trial.

The worst Ebola outbreak in history has killed nearly 4,000 people in Sierra Leone and more than 11,300 overall.

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