New Strain of Ebola

The Atlanta Journal Constitution, your source for up-to-the-minute CDC news, reports that the current Ebola outbreak in Uganda (51 cases and 16 deaths as of Wednesday, according to the WHO) is due to a new, fifth strain of the virus:

Samples arrived at CDC's Biosafety Level 4 labs in Atlanta on Monday. By Tuesday, Ksiazek said, it was apparent this was not a typical Ebola virus.
Dr. Stuart Nichol, a CDC special pathogens team leader, said some molecular tests for Ebola were coming back negative, when another type of test came back positive. The CDC lab was then able to extract a small fragment of the virus' genome.
"It looks, based on this, like it's a new species of Ebola," Nichol said Friday evening.
Previously, there were only four known types of Ebola. The Sudan and Zaire species were discovered in 1976. A strain called Reston was identified in 1989 among monkeys imported to a lab in Virginia. And in 1994, the Ivory Coast strain was identified.
Depending on the strain, the death rate varies. Ebola-Zaire kills about 80 percent of its victims, while the Sudan strain kills about 50 percent, Ksiazek said.