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Surging H3N2 Flu Strain Hits 39 States, Vaccine Effectiveness Varies

11/20/2025

26 2 Full Breakdown

Summary

Story summary

The United States faces a flu season as the H3N2 virus spreads rapidly and causes more severe symptoms.
The Centers for Disease Control and Prevention (CDC) reports rising flu infections in 39 states.
The H3N2 virus has developed mutations that help it evade immunity.
The Health Security Agency in Britain (UK) says the flu vaccine should reduce hospitalizations, with 70–75% effectiveness in children and 30–40% in adults.

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Story summary

The United States faces a flu season as the H3N2 virus spreads rapidly and causes more severe symptoms.
The Centers for Disease Control and Prevention (CDC) reports rising flu infections in 39 states.
The H3N2 virus has developed mutations that help it evade immunity.
The Health Security Agency in Britain (UK) says the flu vaccine should reduce hospitalizations, with 70–75% effectiveness in children and 30–40% in adults.