JUANA SUMMERS, HOST:
Every year, countries around the world take samples of the flu viruses that are circulating locally, and they send them to the Centers for Disease Control and Prevention. It helps the U.S. and other countries keep track of viruses around the globe. But this year, the number of samples shared has dropped, and it could complicate efforts to develop the annual flu shot. NPR's Jonathan Lambert has more.
JONATHAN LAMBERT, BYLINE: CDC is one of seven big labs around the globe that receives thousands of influenza samples each year. In collaboration with the World Health Organization, they all analyze the data and try to understand how influenza is evolving worldwide. Demetre Daskalakis directed the National Center for Immunization and Respiratory Diseases at CDC. He resigned in August.
DEMETRE DASKALAKIS: What we do is work up those viruses. We sequence them. We do, like, tests in ferrets. We do all this stuff to be able to sort of say this virus has a higher pandemic potential. This is a virus that is going to totally circulate next season.
LAMBERT: Those kinds of analyses are crucial for designing annual flu shots and preparing for the possibility of a flu pandemic. They also help CDC make the raw material needed to mass produce vaccines in eggs. But to do all of this, CDC needs other countries to send them the samples of the viruses.
DASKALAKIS: That came pretty much to a grinding halt.
LAMBERT: As of July, Daskalakis says the number of specimens was down by about 60% and more than half of the countries that typically send data hadn't. CDC did not respond to NPR's request for comment. Dan Jernigan directed the CDC's National Center for Emerging and Zoonotic Infectious Diseases in Atlanta. He resigned in August.
DAN JERNIGAN: When those viruses are not coming in, we don't know what to put in the vaccine. And you're going to have less effective vaccines, but also, you're not going to know when these unusual influenza viruses are emerging in other parts of the globe.
LAMBERT: Why is this happening? Daskalakis and Jernigan say because of the U.S. withdrawal from the WHO. They say national influenza centers in other countries may be wary of sharing data with the U.S. now.
DASKALAKIS: Not because they were being malevolent, but because they're like, we don't know if Atlanta is going to share this data with us anymore.
LAMBERT: And it's not just the CDC noticing a slowdown. WHO's Maria Van Kerkhove told NPR they've seen a reduction in the total number of samples sent to the other big labs that track how the virus is changing. She says that's in part because their budget to fund these shipments was cut after the U.S. announced its withdrawal. Here's Kanta Subbarao, a flu researcher at Laval University.
KANTA SUBBARAO: A reduction in the ability of national influenza centers to share their samples will be a huge blow to influenza surveillance.
LAMBERT: Less data overall could mean that next year's flu shot may be a worse match for the virus that ends up circulating. But CDC isn't just getting less flu data. It's also seeing fewer samples of other pathogens like COVID or polio. Daskalakis says that makes it harder to find concerning variants of any virus that might spark the next pandemic.
DASKALAKIS: The system is designed to be able to find needles in the haystack if it gets enough data. If it doesn't get enough, it's going to take longer to find the needle in the haystack.
LAMBERT: As Daskalakis learned during COVID, that time can cost lives.
DASKALAKIS: Every day that we delayed, every day we had less coordination was a day that, like, tens, hundreds, thousands of people were going to die.
LAMBERT: Daskalakis and others worry that story could repeat itself as the U.S. retreats from global efforts to track the globe's most dangerous viruses. Jonathan Lambert, NPR News. Transcript provided by NPR, Copyright NPR.
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