U.S. hasn't sent essential seasonal flu data to WHO ahead of key vaccine meeting
Seasonal flu information is important to monitor outbreaks, inform which strains to include in vaccines
Seasonal flu vaccines need to be updated each year because the virus changes so frequently. But the U.S. hasn't contributed its information on what's spreading there since January, a World Health Organization (WHO) official said.
For seasonal influenza, which forced schools to shut down in some American states earlier this month, the data isn't being shared, Dr. Wenqing Zhang, head of the WHO's global influenza program, told journalists in a webinar on Wednesday.
The U.S. Centers for Disease Control and Prevention (CDC) and U.S. Food and Drug Administration (FDA) normally participate in global discussions hosted by WHO on influenza vaccinations twice a year.
Detailed seasonal flu information is important to monitor outbreaks globally and to inform which influenza strains should be included in vaccines for the Northern Hemisphere's following winter.
"Since 20th January, CDC has not yet reported into the WHO platform of Flunet and FluID," Zhang said, referring to two databases for influenza surveillance. As of last week, the U.S. was publicly releasing some flu information nationally.
When U.S. President Donald Trump was inaugurated on Jan. 20, he called for his country to leave WHO, starting in January 2026.
A WHO meeting is scheduled for next week in London to discuss the composition of influenza vaccines. So far, WHO says the U.S. has not indicated whether it will attend.
At the meeting, participants look at the data to come to a consensus on if the strains in the previous seasonal vaccine are still thought to work or if they need to be updated.
Kanta Subbarao says the U.S. also contributes expertise on vaccine effectiveness and key material used by vaccine manufacturers.
Subbarao, a pediatric infectious diseases specialist and influenza scientist now working at Laval University in Quebec City, served as director of WHO's Collaborating Centre for Influenza in Melbourne, Australia. It is one of five such centres for human influenza along with the U.S. CDC in Atlanta, England, China and Japan.
"I think this is a very bad time for the flu vaccine," Subbarao said.
"The CDC and FDA are very actively involved normally in this process, so it's a little hard for me to fathom what it will look like without them."
Subbarao said the U.S. collaborating centre often receives influenza viruses from Canada and other parts of the Americas as well as Africa and parts of Asia.
The CDC, the FDA and the U.S. Department of Health and Human Services did not respond to requests for comment from CBC News.
U.S. makes a 'big difference'
Dr. Keiji Fukuda, a physician and epidemiologist who has attended influenza vaccine meetings and worked for both WHO and CDC, said it's crucial for U.S. experts to go.
"The interpretation of that data is so important," Fukuda said in an interview. "Hearing your peers discuss how they're looking at it may change how you look at it and these kinds of interactions are how we come up with the best formulations for vaccines."
U.S. participation is crucial to be able to accurately predict which influenza strains are going to be circulating in Canada, the U.S., and Mexico, said Angela Rasmussen, a virologist and principal research scientist at the Vaccine and Infectious Disease Organization in Saskatoon.
"Because the United States is so geographically large, because it is so populous, it really does make a big difference to know which of those influenza strains … are the ones that are going to be predominant and essentially win the race against the other influenza viruses," said Rasmussen. She studies a range of viral pathogens, including flu, and isn't participating in WHO's influenza vaccine meeting.
WHO's influenza surveillance program includes about 130 member states.
The CDC released weekly seasonal flu information on Feb. 14, as well as an update on cases of H5N1 avian influenza that has infected nearly 70 people in the U.S., including a death. Most of those infections have been among farm workers exposed to infected poultry or cows.
Doctors and scientists are watching closely to see if H5N1 or another type of influenza virus gains the ability to spread easily from person to person. That's caused previous global flu pandemics.
On Wednesday, the Canadian government announced the purchase of 500,000 doses of an H5N1 vaccine to help protect those most at risk, such as farm workers and people who handle live avian influenza virus in labs.
WHO said its influenza vaccine meeting will continue whether U.S. delegates show up or not.
ABOUT THE AUTHOR
With files from CBC's Jennifer Yoon and Alison Northcott