The U.S. Centers for Disease Control and Prevention (CDC) reported that the 2025–2026 influenza vaccine showed reduced effectiveness compared to previous seasons. Researchers linked the lower performance to the emergence of a new influenza A(H3N2) subclade that differed from the strain used to manufacture the vaccine.1 The CDC reported overall flu shot effectiveness at 36 percent for the 2025–2026 season, the lowest level since the 2021–2022 season.2
CDC surveillance data indicated that vaccine effectiveness among adults aged 18 years and older was 22–34 percent in preventing influenza-associated outpatient visits and 30 percent in preventing influenza-associated hospitalization. Vaccine effectiveness among children and adolescents was a little higher, at 38–41 percent against influenza-associated outpatient visits and 41 percent against influenza-associated hospitalization.3
Laboratory analysis showed that most genetically characterized influenza A viruses during the season belonged to the A(H3N2) subclade K. Scientists reported that this subclade differed antigenically from the influenza A virus included in the seasonal vaccine formulation.4 Data indicated that subclade K spread more easily, while severity levels remained similar to other strains.5
Influenza activity increased early in the season, with some regions experiencing particularly intense outbreaks. Health authorities described conditions as severe in certain areas such as New York.6
Scientists Discussed Limits of Current Estimates at FDA Meeting
During a virtual meeting, the U.S. Food and Drug Administration’s (FDA) Vaccines and Related Biological Products Advisory Committee (VRBPAC) reviewed data on influenza vaccine performance and discussed plans for future vaccine composition. William Gruner, MS, MB(ASCP), representing U.S. Department of War scientists, told the committee that vaccine effectiveness against influenza-like illness (ILI)—which includes respiratory infections that are caused by other viruses but have symptoms similar to influenza—within department networks was 32 percent among children and 46 percent among adults between Nov. 9, 2025, and Feb. 21, 2026. He said additional data collection later in the season could change the estimates.7
Committee member Hayley Gans, MD, questioned the reliability of the estimates and said the data did not reflect trends she observed in pediatric cases. She also called for broader population representation in CDC influenza surveillance networks.8
At the conclusion of the meeting, the committee unanimously voted to advise the FDA to move forward with updated influenza vaccines. Members recommended that manufacturers develop new shots targeting two influenza A viruses, including an H3N2 component. The recommended vaccine composition matched guidance issued by the World Health Organization (WHO) in February.9
CDC Updates Childhood Flu Vaccine Guidance Citing Limited Evidence
In January 2026, the CDC updated its guidance on routine childhood vaccinations and changed its recommendation for influenza vaccines. The agency said doctors and parents should make decisions about annual flu shots for children through shared clinical decision-making rather than treating the vaccine as a routine recommendation.10
In a memorandum explaining the change, former acting CDC director Jim O’Neill said physicians and parents are best positioned to decide based on a child’s individual needs and characteristics. He stated:
The primary purpose of the childhood influenza vaccine in children is to reduce hospitalizations and mortality in children, as well as transmission to the elderly, who are of higher risk for death but there are no randomized controlled trials demonstrating these benefits.11
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Click here to view References:1 U.S. Centers for Disease Control and Prevention. Interim Estimates of 2025–26 Seasonal Influenza Vaccine Effectiveness — United States, September 2025–February 2026. MMWR 2026; 75(9):116–123.
2 CDC. CDC Seasonal Flu Vaccine Effectiveness Studies. Mar. 16, 2026.
3 CDC. Interim Estimates of 2025–26 Seasonal Influenza Vaccine Effectiveness — United States, September 2025–February 2026. MMWR 2026; 75(9):116–123.
4 Ibid.
5 Stobbe M. Flu vaccines didn’t work that well in the US, officials find. AP News Mar. 13, 2026.
6 Ibid.
7 Stieber Z. Report: Influenza vaccine effectiveness lower in recent months. The Signal Mar. 16, 2026.
8 Ibid.
9 Ibid.
10 U.S. Department of Health and Human Services. Fact Sheet: CDC Childhood Immunization Recommendations. Jan. 5, 2026.
11 Ibid.
6 Responses
Well, not having any vaccines, we seemed to be very resilient to whatever was floating around. No shot. No flue. See how that works? These faux experts might want to try experimenting with these things called vitamins and organic non gm pesticide free foods, getting out of their stuffy office buildings and labs. The cult of vaccination zealots carries on another day. Endless meetings and never ending committee’s. They’ll never figure anything out and actually land on a workable program or position. The program has evolved into a purposeful bureaucracy which milks a never ending stream of taxpayer dollars. So close yet again. Did not quite make it. They’ll do better next round. Promise. Be patient. Keep paying. Submit. Obey.
Amen
This is nothing new. The flu shot hasn’t been effective at preventing the flu for decades. The lump deaths from pneumonia (often not even related to the flu) in with deaths from the flu, is increase the number of deaths, to scare people into getting the shot. I believe highest % of effectiveness of the flu shot ever was only 50 or 60%. At the the same time, it has mercury than most other shots. Why would anyone inject that much mercury into their body on the small chance that they won’t get the flu, let alone give it to their children?
https://www.vacsafety.org/new-study-flu-vaccination-linked-to-27-increased-risk-of-flu/
I don’t believe the study was valid.
last year Cleveland clinic found that employees with vaccine had 27% MORE flu!
In this study they knew the vaccine status before employees got sick.
all employees had access to early treatment, hygiene, housing, food.
Also in 2005 NIH found no benefit from flu vaccine.
The elephant that’s very much still in the room is there’s still no vaccine on the schedule that’s been tested against a proper placebo, properly powered and adequately followed up!
The flu vaccine has NEVER been effective. It’s pushed by big pharma because it makes billions of dollars for them.