The first clinical trial of an Ebola vaccine in the outbreak gripping the Democratic Republic of Congo began Friday, the head of the World Health Organization said.

KINSHASA, DRC | Xinhua | Africa’s fight against Ebola faces mounting challenges as the virus spreads across national borders, with the second death in Kenya and uncertainties over the source of Nigeria’s first infection complicating containment efforts, even as a major vaccine trial launched Friday in the Democratic Republic of the Congo (DRC) offers fresh …