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Interim Estimates of 2025–26 Seasonal #Influenza #Vaccine #Effectiveness — #USA, September 2025–February 2026 (CDC MMWR)

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By G.M.

 


Abstract

In the United States, annual influenza vaccination has been recommended for all persons aged ≥6 months, including during the 2025–26 season. Interim influenza vaccine effectiveness (VE) estimates were calculated for patients with acute respiratory illness–associated outpatient visits and hospitalizations from three U.S. respiratory virus VE networks during the 2025–26 influenza season, using a test-negative case-control design. Among children and adolescents aged <18 years, VE was 38%–41% against influenza outpatient visits and 41% against influenza-associated hospitalization. Among adults aged ≥18 years, VE was 22%–34% against influenza outpatient visits and 30% against influenza-associated hospitalization. Among children and adolescents, VE against influenza A ranged from 37% (against outpatient visits) to 42% (against hospitalization) across settings; among adults, VE against influenza A ranged from 30% (against hospitalization) to 34% (against outpatient visits) across settings. Among children and adolescents, VE against influenza A(H3N2)–associated outpatient visits was 35% and against influenza A(H3N2)–associated hospitalization was 38%. VE against influenza B outpatient visits ranged from 45%–71% among children and adolescents and was 63% among adults. Other estimates of VE were not statistically significant or were not reportable. Although interim influenza VE is lower during the 2025–26 influenza season than it was during recent influenza seasons, these findings demonstrate that influenza vaccination still provides protection against influenza. CDC recommends influenza vaccination; U.S. influenza vaccines remain available for persons aged ≥6 months.

Source: 


Link: http://dx.doi.org/10.15585/mmwr.mm7509a2

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