The outbreak has since recorded about 4,200 confirmed cases and more than 1,900 deaths, according to the latest government figures, making it the fastest-growing Ebola outbreak on record. The outbreak is being driven by the rare Bundibugyo virus, for which there are currently no approved vaccines or treatments. Early testing for the more common Ebola virus contributed to delays in identifying the strain. Cases detected outside the affected region have so far been identified and contained without sustained transmission. However, health authorities are struggling to contain the outbreak amid conflict, unpaid health workers, misinformation and shortages of protective equipment.