The World Health Organization said Thursday that 31 of 38 confirmed Ebola cases have resulted in deaths in southern Congo, where authorities are battling a new outbreak of the deadly virus. “More than 500 health care workers and contacts have received their vaccination, offering them crucial protection,” said Dr. Patrick Otim from WHO Africa’s program. A fresh Ebola outbreak was announced by Congolese authorities on Sept. 5 in the locality of Bulape in Kasai, a south-central region in Congo close to Angola. Last week, the Africa Centers for Disease Control and Prevention said the disease had spread from two districts to four. Doses have been flown into Bulape in small batches because of limited storage capacity and difficult access to the area, officials said.