WHO and CDC increased diagnostic testing focus for the Bundibugyo Ebola strain as the outbreak expands in parts of the Democratic Republic of Congo and Uganda. WHO raised the threat level from High to Very High after assessing the likelihood the outbreak could spread nationwide in the DRC. CDC incident manager Satish Pillai outlined the agency’s approach to testing and containment, including deploying disease detectives and training viral hemorrhagic fever experts. Pillai said early GeneXpert testing initially missed Bundibugyo because it does not detect the less common species, prompting additional testing and sequencing after sample transport delays. Once positive results were obtained, genomic sequencing followed within 24 hours. The update underscores how fast diagnostic pathway adjustments—moving to assays that can differentiate species—become operationally critical during fast-moving viral hemorrhagic fever outbreaks.