Surveillance for vector-borne diseases among active and reserve component service members, U.S. Armed Forces,...

This report summarizes available health record information about the occurrence of vector-borne infectious diseases among members of the U.S. Armed Forces during a recent 7-year surveillance period. Information about confirmed, possible, and suspected cases was obtained from electronic reports of reportable medical events (RMEs) and records of diagnoses documented during hospitalizations and outpatient healthcare encounters. Lyme disease and malaria were the most common diagnoses among confirmed and possible cases. Diagnoses of chikungunya and Zika were elevated in the years following their respective entries into the Western Hemisphere. Large numbers of diagnoses of arboviral diseases were recorded in the category of suspected cases, but the overwhelming majority were associated with coding errors and tentative diagnoses not subsequently confirmed. For many confirmed cases, documentation could not be found in healthcare databases for positive laboratory tests that would be the basis for confirmation. Discussion covers the limitations of the available data and the importance to surveillance of RMEs, confirmatory laboratory tests, and accurate recording of diagnoses and their codes.