Each year, the influenza vaccine is promoted across the country—recommended by public health authorities, advertised widely, and often required by medical workplaces, schools, and childcare centers. Yet, the vaccine’s effectiveness remains uncertain, as it is formulated months in advance based on predictions of which influenza virus strains will predominately circulate. This season, the flu shot’s effectiveness is estimated at about 50 percent.1
Flu vaccines are formulated by scientists using data from around the world to make a best educated guesses as to which type A and type B influenza strain they believe should go into the next season’s influenza vaccine. Since influenza viruses are constantly evolving, the vaccines must be updated each year in an attempt to match the most common strains or most concerning strains.2
The process of influenza virus strain selection is coordinated by the World Health Organization (WHO) through its Global Influenza Surveillance and Response System (GISRS). This program consists of 152 National Influenza Centers in 129 countries which monitor how the circulating influenza viruses spread, mutates, or changes. In February, a panel is held where expects recommend the influenza virus strains for the upcoming Northern Hemisphere flu season. In September, a second meeting is held to select strains for the Southern Hemisphere.2
Once influenza strains are selected, vaccine manufacturers use selected strains to begin a nine-month production and distribution process.2
Lowest Effectiveness of Flu Vaccine was 19 Percent in 2015 Flu Season
The U.S. Centers for Disease Control and Prevention’s (CDC) data shows that over the past 10 years the flu vaccine has had an adjusted effectiveness between 19 percent in the 2014-2015 flu season and 56 percent in the 2024-2025 flu season.3
Current CDC recommendations indicate routine annual influenza vaccination for all individuals over six months of age. Pregnant women are also encouraged to get a flu shot.4
Despite the vaccine failing to work more than half the time, many workplaces, daycares, or schools require annual vaccination. Johns Hopkins University has required students, faculty, and staff to receive an annual flu shot. The mandate for influenza vaccination has been in place since 2020 and students have to submit proof to an online portal. Faculty and staff members automatically have their vaccination record submitted.5
“Protecting Others” Still a Marketing Strategy to get Vaccinated Despite 50 Efficacy
The flu shot marketing campaigns emphasizing that it is everyone’s duty to get an annual flu shot to create “community immunity” by protecting others persists, despite acknowledged low effectiveness rates for influenza vaccine.
Baylor Health’s website states:
As flu season is upon us once again, there’s something you need to know: Getting a flu shot isn’t all about you. It’s also about the people who are unable to get flu shots, the ones whose immune systems can’t fight off a virus like yours can and the ones already weak from battling cancer and other illnesses. When you get a flu shot, it doesn’t just protect you. It protects all of us.6
Life-altering complications to influenza vaccine is the most common vaccine inury claim filed with the federal Vaccine Injury Compensation Program (VICP). Guillain-Barré syndrome (GBS), which involves inflammation of nerves and can result in partial or full body paralysis, is the number one alleged vaccine injury associated with influenza vaccine.7
If you would like to receive an e-mail notice of the most recent articles published in The Vaccine Reaction each week, click here.
Click here to view References:1 Wappes J. Protection from flu vaccine around 50% for Southern Hemisphere, data reveal. CIDRAP Oct. 17, 2025.
2 Rasmussen A, Lamb C. How are flu vaccine strains chosen each year? Vaccine and Infectious Disease Organization Feb. 24, 2025.
3 CDC Flu Vaccines Work. CDC seasonal flu vaccine effectiveness studies. May 30, 2025.
4 U.S. Centers for Disease Control and Prevention. ACIP recommendations summary. Aug. 28, 2025.
5 Hub staff. Flu vaccine requirements announced for 2025-26. John Hopkins University Sept. 15, 2025.
6 Glausier G. Herd immunity: why getting the flu shot isn’t all about you. Baylor Scott & White Oct. 17, 2017.
7 Cáceres M. What’s so effective about a flu vaccine that’s less than 10 percent effective? The Vaccine Reaction July 3, 2019.
8 Responses
“effectiveness is estimated”, does not sound very scientific to me.
“Lowest Effectiveness of Flu Vaccine was 19 Percent” LOL and that is not even the lowest. I recall one year it was 9%
At 76 years of age, I have never received a flu shot neither did my parents or any of my children or grandchildren. I have had the “flu” (if you want to call it that) 3 times in my life; 1958, 1965, 1977. Oh and BTW, there was never such a thing as “Flu Season” until flu shots became an annual “thing”. Just sayin. When i see BS, that is what I will call it. This is total BS. And, for good measure, why would anyone subject themselves to this possibility?;
“Life-altering complications to influenza vaccine is the most common vaccine injury claim filed with the federal Vaccine Injury Compensation Program (VICP). Guillain-Barré syndrome (GBS), which involves inflammation of nerves and can result in partial or full body paralysis, is the number one alleged vaccine injury associated with influenza vaccine.”
Modern Influenza strains essentially never kill the few in the US WITH OPTIMAL VITAMIN D3 LEVELS of 50-80 ng / ml; many remain asymptomatic. The “normal” 20-30 ng /ml is archaic. The only side effects at these levels are BENEFITS, summarized as a decrease in the chronic “inflammaging” diseases e.g. CA, Atherosclerosis, autoimmunity, diabetes, depression, plus a substantially improved IQ of kids born of optimally sufficient mothers. Population 50-80 ng/ml will likely add 3 years to our US healthspan! Checking D3 levels to guide the dose is prudent. Substantial savings, not costs, are the economic impact. The dangerous and costly practice of influenza vaccination as a “public health” measure cannot be justified when compared to optimizing vitamin D levels. Plus, optimal D3 has a similar benefit for Covid and is a “two-for-one” opportunity. Our entire vaccination strategy must be transparently re-evaluated. Please view the documentary https://www.aninconvenientstudy.com. See the analysis of Henry Ford Hospital data on vaccination harm documented in the Federal Record in the Congressional Testimony of Senator Ron Johnson.
REFORM: Health care providers must document good health outcomes to get paid. Modern system make this transparency affordable (Henry Ford has long had all the data, just weren’t sharing it). Restructured reimbursement rates will no longer pay highest profits for late-stage disease treatment. Instead the highest profits must be paid for creating optimal health at a reasonable cost, for value. Successful providers and wise patients will follow the money and refocus on high value prevention e.g. D3 optimal sufficiency.
RESULT: US rapidly transitions from the World’s worst to the best value health care system.
According to a study published in the journal Lancet a few years ago, in a normal year, 2.7 unvaccinated people out of 100 will get the flu. In a totally vaccinated population 1.2 people out of 100 will get the flu. It only prevents 1.5 people out of 100 from getting the flu. 1.5 divided by 2.7 gives you roughly 55%. That’s how they get “60%” effective when it prevents 1.5 cases per 100 (1.5%). Figures don’t lie but liars figure.
Why is any attention given to the liars who lie to promote their poison product? They lie about the safety and the effectiveness – it is all a LIE.
Flu (and covid) vaccine effectivness studies do not measure effectivness at preventing infection or transmission; they only measure rates of hospitalization or emergency room visits. And often they only look at the high risk groups (elderly, young children, and the nebulous category of “pre-existing conditions.” If public health officials are claiming that your vaccine “protects others” or protects the community, they are misleading (unless they mean the community is protected by reducing flu hospitalizations). For example, this CDC MMWR study: Interim Effectiveness Estimates of 2025 Southern Hemisphere Influenza Vaccines in Preventing Influenza-Associated Outpatient and Hospitalized Illness — Eight Southern Hemisphere Countries, March–September 2025. https://www.cdc.gov/mmwr/volumes/74/wr/mm7436a3.htm
Another meaningless statistic from faux-scientists.
55% is a extreme high expectation.
Last year the Cleveland clinic measured -27% effective.
Yes negative. The employees that got jab were more likely to get Flu.
I believe it is more likely -4% based on other data analysis.
I wonder 🤔 what the Cleveland clinic will measure this time.
More I wonder how many Cleveland clinic employees will get Flu jab this year. Last year is was 80%.
In the Cleveland clinic study they knew the vaccine status of all people in the study. The decision to get jab was not based on access.
The Minnesota study they compare vaccine rate with other people in the hospital not a good control group.
The annual flu is made in a lab. So is the flu shot. I used to think, how could they make a vaccine for a new flu? Then Dr. Judy Mikovits wrote a tell all book about how Fauci made so many of these diseases and virus in a lab, like Ebola and HIV. Not sure why this article is not well researched. New info says that taking the flu shots enhances you to get the flu.