Genomes reveal start of Ebola outbreak
When the young woman arrived at the Kenema Government Hospital in Sierra Leone in late May, she had high fever and had just miscarried. The hospital suspected she had contracted Lassa fever, because the viral disease is endemic in the region and often causes miscarriages. But Ebola virus disease, another hemorrhagic fever illness, had been spreading in neighboring Guinea for months, so when she began bleeding profusely, staff tested her for that virus as well. The results were positive, making her the first confirmed case of Ebola in Sierra Leone.
The young woman, who eventually recovered, is now at the heart of a tragic but potentially important research tale. In a paper online this week in Science, a collaboration led by Stephen Gire and Pardis Sabeti of Harvard University and the Broad Institute in Cambridge, Massachusetts, report sequencing and analyzing the genomes of Ebola virus samples from 78 people in Sierra Leone who were diagnosed with Ebola between late May and mid-June, including the young woman who came to Kenema’s hospital. The 99 complete sequences—some patients were sampled more than once—provide insights into how the virus is changing during the outbreak, which could help improve current diagnostic tests and, in the long term, guide researchers working on vaccines and treatments.