More than 400 contacts being traced in Congo's latest Ebola outbreak, health officials say. DAKAR, Senegal — Health workers are monitoring more than 400 people amid an Ebola outbreak in a remote corner of Congo where already three deaths have been blamed on the virus, the World Health Organization said Thursday. An experimental vaccine has been developed since the West African epidemic in 2014-2016 that left more than 11,000 people dead, but WHO said it is still awaiting permission from the Congolese government to use it.