The U.S. Department of Health and Human Services (HHS) is touting a biosurveillance program that has surpassed 1 million voluntary participants, aimed to better detect and respond to potential health threats from international visitors who enter the United States. The Centers for Disease Control (CDC) announced Jan. 30 that its Traveler-Based Genomic Surveillance (TGS) program just hit the “significant” numerical milestone, helping to uncover emerging public health warnings at domestic borders.