Tracking viruses that travel: How the CDC targets COVID, RSV and flu

An international travel surveillance program that the Centers for Disease Control and Prevention started to track worldwide movement of COVID-19 variants is now expanding to include other respiratory viruses.

Are you traveling around the world this holiday season? Would you like to know if viruses are tagging along?

Alex Poole is one traveler who says yes.

"Absolutely, absolutely. RSV, flu, COVID, all of it," Poole said.

Airline passengers flying this holiday season could be part of this effort. The CDC is expanding its travel-based Genomic Surveillance program to provide early detection, not just of new and rare COVID variants, but also influenza and RSV.

"It's always helpful to know what's going on with transmission," said Los Angeles County Public Health Director Dr. Barbara Ferrer.

Dr. Ferrer added the tracking is done by collecting saliva samples from volunteers - cooperating passengers at major airports such as LAX - and by checking the wastewater on planes.

"We want a picture of what's happening in the world. The advantage of wastewater is you get your information pretty close to real time," Ferrer said.

For example, during the early days of the pandemic, the traveler-based Genomic Surveillance program detected a COVID-19 variant, BA2.86, entering the U.S. within days of its global identification.

Flu, RSV and COVID is a triple threat that's been plaguing Americans these past few winters. Being able to track them will help public health departments target their resources.

Wastewater monitoring is a passive and convenient way to gather information.

"We're fortunate because in L.A. County, we have good surveillance through our wastewater systems," Ferrer said. "You know, we're collecting information that covers really about 80% of L.A. County residents."

Dave Skebba, a traveler we caught up with at LAX, said: "I think that anytime you get more data, it's better. You can make better decisions with more data."

Since September, the CDC has enrolled more than 360,000 air travelers. Participation is voluntary and anonymous. The program covers flights from more than 135 countries.

Dr. Ferrer says knowing what's heading into our communities will save lives.

"We need to worry a lot about the stress on our healthcare systems," Ferrer said.

"And of course, we all want to minimize the number of people who die. It's very important that we still understand what's going on with transmission."