Health workers battling an Ebola outbreak in eastern Democratic Republic of Congo lack the personnel to identify suspected cases, the ambulances to transport them and even the construction materials to build isolation wards, officials and aid workers told Reuters . A month after the World Health Organisation (WHO) declared an international emergency, the outbreak of the rare Bundibugyo strain has grown to more than 800 confirmed cases, with warnings mounting that it could become the worst on record, surpassing the 2014-16 West Africa epidemic that killed more than 11,000 people. Health teams are so stretched that tens of thousands of contacts of those cases remain untraced, Jean Kaseya, director general of the Africa Centres for Disease Control and Prevention, told Reuters , pointing to insecurity and the urban, mining-heavy setting of the outbreak as central obstacles.