The head of Africa’s Centres for Disease Control and Prevention warned on Tuesday that the Ebola outbreak in the Democratic Republic of Congo (DRC) could be the worst ever, saying that currently tens of thousands of contacts of those ill with the disease had not been traced.

There have been more than 800 confirmed cases and almost 200 deaths from an Ebola outbreak declared in May in the DRC.

(Bloomberg) -- Ebola treatment centers in eastern Democratic Republic of Congo are becoming overwhelmed as confirmed cases surge past 800 and health workers struggle to track…