Sierra Leone is in mourning after a leading virologist who risked his life to treat dozens of Ebola patients became the latest health care worker to die from the lethal virus, which has now killed more than 670 people across West Africa.
Dr. Sheik Humarr Khan was working at the Kenema Government Hospital in eastern Sierra Leone when Ebola broke out in the country for the first time this spring.
Several of his nurses became sick, and then last week Khan was also confirmed to have Ebola. He underwent treatment at an isolation unit operated by the medical aid organization, Médecins Sans Frontières, but died Tuesday night, according to his older sister.