Health ❯ Public Health ❯ Infectious Diseases

Influenza

Vaccination Flu Season H3N2 Virus Flu Vaccination H3N2 Epidemiology H3N2 Strain H3N2 Variant H3N2 Subclade K Influenza A H3N2

H3N2 Subclade K Fuels Early U.S. Flu Surge With Millions Sick

Officials report preserved protection against severe disease despite a partial vaccine mismatch.

Peru Confirms Six H3N2K Cases as Lima Emergency Rooms Strain, While Argentina Ramps Up Surveillance and Vaccination

Flu Surges Nationwide as H3N2 Subclade K Dominates, Straining Hospitals Before Holidays

Peru Confirms Two H3N2 ‘Subclade K’ Cases in Lima as Vaccination Drive Widens

WHO Says Early H3N2 ‘Subclade K’ Flu Wave Is Straining Hospitals Across Europe

Peru Confirms Two Pediatric H3N2 Subclade K Cases as Region Ramps Up Flu Precautions

Mexico Confirms First H3N2 Subclade K Case as WHO Flags Wider Global Spread

Mexico Confirms First Case as Fast-Spreading H3N2 Subclade K Drives Early Flu Surge

H3N2 ‘K’ Flu Surges as Central Florida Warns of Tridemic Risk for Disney Travelers

Drifted H3N2 ‘Subclade K’ Spreads to U.S. as Early Flu Wave Builds

Detroit Medical Center Tightens Visitor Rules as Flu Cases Climb

New York Flu Surge Accelerates as H3N2 Variant Gains Ground

Drifted H3N2 Variant Drives Early U.S. Flu Rise as Hospitalizations Increase

Mutated H3N2 Strain Spurs Early Flu Rise as UK Admissions Climb and California, Chicago Flag Increases

Drifted H3N2 ‘Subclade K’ Drives Early U.S. Flu Uptick Before Holidays

New H3N2 Variant Emerges as Canada’s Flu Season Starts and U.S. Activity Remains Low

LA and Riverside Counties Report First Flu Deaths of 2025–26 Season

Early H3N2 Surge Triggers EU Vaccine Push as mRNA Flu Shots Outperform in Phase 3

ECDC Warns of Early Flu Surge in Europe and Urges Immediate Vaccination

New H3N2 ‘Subclade K’ Drives Early Flu Surges as U.S. Officials Urge Vaccination