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New H3N2 Variant Spreads, Threatens Vaccine Effectiveness

12/25/2025

31 5 Full Breakdown

Summary

Story summary

The new influenza A H3N2 subclade K variant is spreading rapidly in the United States.
The World Health Organization notes the variant's evolution may limit this season's vaccine effectiveness.
The Centers for Disease Control and Prevention (CDC) reports nearly 4.6 million illnesses and 1,900 flu deaths this season.
Dr. Neil Maniar warns that lower vaccination rates could worsen the season.

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Story summary

The new influenza A H3N2 subclade K variant is spreading rapidly in the United States.
The World Health Organization notes the variant's evolution may limit this season's vaccine effectiveness.
The Centers for Disease Control and Prevention (CDC) reports nearly 4.6 million illnesses and 1,900 flu deaths this season.
Dr. Neil Maniar warns that lower vaccination rates could worsen the season.