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. It is estimated that more than 1 billion flyers fill U.S. airports each year.
TGS is described by HHS as “one of many tools” utilized by the federal government to strengthen disease surveillance and protect the American people. Travelers at select U.S. airports are requested to provide voluntary and anonymous samples, with the goal of providing early detection of possible pathogens and variants before they spread broadly within the U.S.
Pathogens that are sought include viruses like influenza A, influenza B, RSV, and the SARS-CoV-2 virus that causes COVID-19.
When reached for comment by Military.com, HHS referred to a statement and provided no additional information.
“The United States is the world’s leading authority in public health,” HHS Deputy Secretary and Acting CDC Director Jim O’Neill said in a statement. “The broad participation of travelers enhances our ability to safeguard the nation using tools that are developed, operated, and governed here at home without reliance on unaccountable global bureaucracies.”
The Biosurveillance Testing Process
Airports participating in the TGS program are located in Boston, Chicago, Los Angeles, Miami, Newark, New York City (JFK), San Francisco, Seattle and Washington D.C.(Dulles), according to the CDC website.
The process for enabling timely detection of communicable diseases while reducing outside intervention that could disrupt travel and trade involves the use of nasal swabs.
Once international travelers arrive at any of the aforementioned airports, they can volunteer to self-collect two nasal swab samples and then complete a short survey. One sample is pooled with other travelers' samples.
Once collected, the individual and pooled samples are shipped to a laboratory. If pooled samples are positive by reverse transcription polymerase chain reaction (RT-PCR) for pathogens of public health concern, individual samples are then tested.
Those individual samples that test positive for select pathogens undergo sequencing to determine variants, strains, or mutations of public health importance. They are then shared with CDC laboratories for further genomic characterization, which can provide information about the transmissibility of a new strain or variant, virulence, and a response to current treatments or vaccines.
Monitoring wastewater can also lead to pivotal results, accomplished by collecting samples from travelers who use airplane bathrooms and wash their hands, for example.
Wastewater samples are tested in two main ways. One involves collection from individual airplanes using a custom-made collection device during routine servicing by a lavatory truck.
The other method is collection from an airport triturator—a consolidation point where lavatory trucks deposit airplane wastewater—using an automated sampler. A triturator does not include airport terminal waste.
Those specifics samples are then shipped to a lab for digital polymerase chain reaction (dPCR) testing.
The CDC has analyzed more than 2,600 airplane wastewater samples as part of TGS, according to HHS.
Consistent Updates
TGS launched in 2021 and is credited for detecting and reporting the first two detections of influenza H3N2 subclade K to public repositories seven days before the next publicly reported sequence.
In October 2023, the program expanded to cover a list of more than 30 viral and bacterial targets. That led to the successful first phase of multi-pathogen testing and sequencing in November and December of that year, detecting positive samples containing several pathogens including influenza A and B, RSV, and Mycoplasma pneumoniae—a bacteria that causes pneumonia.
A TGS data page posted on the CDC website summarizes data from individual travelers rather than pools of multiple travelers, updating the most recent available results weekly at 1 p.m. ET on Friday.
The most recent data uploaded on Jan. 30 shows weekly trends of SARS-CoV-2 test positivity from nasal swab samples collected from arriving international travelers—from Jan. 22, 2023, to Jan. 11, 2026.
The heights of positive detections hit 5.2% on July 14, 2024, with the lowest detected rate of 0.2% showing for Dec. 28, 2025.
The TGS program operates through public-private partnerships with organizations including Ginkgo Biosecurity and XWell.
Military.com reached out to both companies for comment.
“The frequency of new outbreaks around the world reminds us every day that persistent and strategically focused biosurveillance is paramount to ensure readiness and rapid response,” Matt McKnight, general manager of Ginkgo Biosecurity, said in a statement posted on the company’s website.
