The authors of the letter clarify an inaccuracy in a previous publication by Cao-Lormeau et al. regarding the first Zika virus (ZIKV) outbreak reported outside Africa and Asia. The initial outbreak on Yap Island, Federated States of Micronesia, was not retrospectively identified from serum samples incorrectly diagnosed as dengue virus. Instead, it was first identified by the Yap State Department of Health Services and confirmed through an active, coordinated investigation with assistance from international partners. The discovery of ZIKV as the etiologic agent was confirmed through testing at the Centers for Disease Control and Prevention's Arboviral Diseases Diagnostic Laboratory. The response from Van-Mai Cao-Lormeau acknowledges the inaccuracy and provides a more accurate description of the outbreak investigation, emphasizing the importance of the initial efforts in Yap State.The authors of the letter clarify an inaccuracy in a previous publication by Cao-Lormeau et al. regarding the first Zika virus (ZIKV) outbreak reported outside Africa and Asia. The initial outbreak on Yap Island, Federated States of Micronesia, was not retrospectively identified from serum samples incorrectly diagnosed as dengue virus. Instead, it was first identified by the Yap State Department of Health Services and confirmed through an active, coordinated investigation with assistance from international partners. The discovery of ZIKV as the etiologic agent was confirmed through testing at the Centers for Disease Control and Prevention's Arboviral Diseases Diagnostic Laboratory. The response from Van-Mai Cao-Lormeau acknowledges the inaccuracy and provides a more accurate description of the outbreak investigation, emphasizing the importance of the initial efforts in Yap State.