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Flu Shots: Facts & Fallacies

Vaccination is one of science’s greatest accomplishments; vaccines have prevented millions of deaths and eliminated smallpox forever. But rejection of vaccination is as old as vaccination itself. Some objections to it needn’t be taken seriously, like the argument that illness and death are part of God’s plan and humans mustn’t try to thwart His will. Or the chiropractor who told me “germs don’t cause disease.” However, some objections to specific vaccines require serious scrutiny: those that are based on an interpretation of the evidence that differs from the interpretation of the experts who write the immunization guidelines.

Of all vaccines, flu shots have come in for the most criticism. There are valid reasons to be skeptical. They are the least effective of all our vaccines. The influenza virus is constantly changing, and there is a lot of guesswork involved in choosing which strains to use in each year’s vaccine. And some of the studies on which the recommendations are based are flawed.

One of the flu vaccine’s most outspoken critics is Tom Jefferson, head of the Vaccine Field Group at the Cochrane Database Collaboration. He says “Flu researchers have been fooled into thinking vaccine is more effective than the data suggest.” He is absolutely right about that. But he goes too far when he characterizes all the published research as “rubbish.” Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, is more circumspect. He says, “I have no doubt that it is effective in conferring some degree of protection. To say otherwise is a minority view.”

Flu vaccine research is problematic. As many as half of people who have “flu-like” illnesses don’t actually have influenza; there are more than 200 other pathogens that can cause the same symptoms. The risk of influenza varies from year to year according to the virulence of the circulating strains. There is often a mismatch between the circulating strains and the strains in the vaccines. Many studies have measured antibody levels rather than actual decreases in the number of cases of influenza. Measuring deaths from flu can be misleading because flu can kill indirectly by making people more susceptible to complications such as pneumonia. If they hadn’t had influenza, they wouldn’t have died of pneumonia. Jefferson says “When an old person dies of respiratory failure after an influenzalike illness, they nearly always get coded as influenza.” Of course that’s not accurate unless the diagnosis of influenza was laboratory-confirmed. By the same token, however, some deaths coded as heart attacks or pneumonia may have been due to influenza.

The benefit to the population depends on individuals getting the vaccine. They may not benefit personally, but they indirectly benefit others by reducing transmission rates in the community and increasing herd immunity.

Jefferson calls for placebo-controlled trials, which most experts reject as unethical. The FDA required placebo-controlled trials before the flu vaccine first went on the market; those studies established that it is protective, and it wouldn’t be ethical to deny that protection to a placebo control group.

The claim that flu vaccine reduces death rates by 50% is almost certainly wrong. But there is compelling evidence that flu vaccines work. In studies where vaccinated subjects were deliberately infected with influenza virus that matched the strains in the vaccine, the protection rate was 96%.

The Science-Based Medicine blog’s Mark Crislip, an infectious disease specialist, reviewed the same published evidence that Jefferson had, and he emphatically disagrees with him. Even if Jefferson is right that the flu vaccine doesn’t reduce all-cause mortality, there is compelling evidence that it reduces the infection rate and the flu-related mortality of populations. The benefit to the population depends on individuals getting the vaccine. They may not benefit personally, but they indirectly benefit others by reducing transmission rates in the community and increasing herd immunity.

Certain people are particularly vulnerable and more likely to die if they get the flu: infants too young to be vaccinated, the immune-compromised (whether from disease or from immune- suppressing medications), pregnant women, and the elderly. The elderly are not as well protected by the vaccine because they don’t develop as high a level of antibodies as younger people. Fortunately a higher dose flu vaccine is now available with four times as much antigen. It is recommended for those over 65, and has been shown to decrease the incidence of flu in that population.

Crislip concludes, “The flu vaccine is of benefit. And the more people who get the vaccine, the greater the benefit for everyone.” As we like to say, “Don’t get the flu vaccine for yourself, get it for Grandma.”

Here are some of the many fallacious reasons people refuse to get their flu shots:

  1. It contains a neurotoxin, mercury, in the form of thimerosal. (Only the multidose vials contain thimerosal, you can request the single-dose version; and anyway thimerosal doesn’t cause autism and the World Health Organization says it’s safe.)
  2. I don’t need the vaccine because I’ve never had the flu. (Yet. There is no guarantee that you won’t get it. I’ve never had a house fire, but that’s not a reason to drop my fire insurance.)
  3. The vaccine gave me the flu. (Impossible. The injectable vaccine contains no live virus, and the nasal spray vaccine contains an attenuated form of virus too weak to cause the disease.)
  4. It doesn’t work: I was vaccinated but I got the flu anyway. (You may have had another flu-like illness or flu from a strain not covered by the vaccine. And if you got the flu from a strain that was covered, you probably had a much milder case than you would have without the vaccine.)
  5. It causes dangerous side effects. (Most side effects are mild and transient. Serious side effects are extremely rare. The disease is far more dangerous than the vaccine. A sore arm for a couple of days is a small price to pay for avoiding a disease that could kill you.)
  6. I can protect myself naturally with Echinacea, Airborne, vitamin D, and other natural preventive measures. (Dream on!)
  7. The flu isn’t so bad. (Yes it is! It can kill people, put them in the hospital, and cause symptoms so bad they wish they would die.)
  8. It hasn’t been evaluated for safety. (It was evaluated for safety before it went on the market, and surveillance is ongoing. There are 1342 references on PubMed on the safety of flu vaccine.)
  9. I don’t want to spend the money. (A funeral or a hospital stay costs a lot more than a flu shot.)
  10. “Injecting organisms into your body to provoke immunity is contrary to nature,” according to the infamous Dr. Mercola. (Nature kills people. Medicine is all about trying to keep nature from hurting people. “Contrary to nature” is a good thing.)
  11. I heard the vaccine causes narcolepsy. (In 2009 there were reports of an association between narcolepsy and one specific brand, Pandemrix, but only in a few countries and not in others. Correlation is not causation and it is still not certain whether the vaccine was responsible. No other brand has been linked to narcolepsy, and Pandemrix was never licensed for use in the US.)
  12. Fewer than 100 children die each year from the flu. (Preventing death is not the only reason to vaccinate. Children have the greatest rate of infection with the flu; 10–40% of all children are infected each year, and 1% of those are hospitalized. Children are the primary source from which influenza spreads through the population. And even one preventable death of a child is a tragedy.)
  13. There’s formaldehyde in the vaccine. (It’s used in manufacturing, but if there’s any left in the final product, it’s too little to measure. The body already contains a million times more formaldehyde from natural metabolic processes than the highest estimate of what might be in the vaccine.)

When healthcare workers are vaccinated, patient mortality declines. Some employers require healthcare workers to get the flu shot. This mandate has created a lot of controversy. One doctor said “Even if it were true that healthcare workers were transmitting flu to patients and that vaccination could prevent this from happening, forcing a professional to do even that which is beneficial is profoundly immoral.” But no one is being forced. A healthcare worker always has the right to refuse vaccination and take whatever consequences the employer imposes. The hospital has a duty to protect its vulnerable patients by not exposing them to unvaccinated staff. Those who argue for “health freedom” want the freedom to act foolishly and irresponsibly.

Skeptic magazine 21.2

This article appeared in Skeptic magazine 21.2 (2016)

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I once had a long e-mail debate with a man who refused to get the flu shot. He gave me his reasons one by one and I showed him evidence that refuted each of them. He finally agreed that I was probably right but said he still wasn’t going to get the shot because he’s afraid of needles!

I’ve been getting an annual flu shot for several decades now. I’ve never had the flu; but I’ve seen the harm it can do, and I want to keep taking every possible precaution to reduce my chances of getting it. And I want to protect others in my community.

Influenza kills around 36,000 people annually in the U.S. If even a few of those deaths can be prevented, isn’t the vaccine worthwhile? If even a few people can be spared the suffering of a nonfatal influenza attack, isn’t it worthwhile? If it will help protect the very young, the elderly, and the immunecompromised, shouldn’t the rest of us be altruistic enough to get the vaccine for their sake? END

About the Author

Dr. Harriet Hall, MD, the SkepDoc, is a retired family physician and Air Force Colonel living in Puyallup, WA. She writes about alternative medicine, pseudoscience, quackery, and critical thinking. She is a contributing editor to both Skeptic and Skeptical Inquirer, an advisor to the Quackwatch website, and an editor of, where she writes an article every Tuesday. She is author of Women Aren’t Supposed to Fly: The Memoirs of a Female Flight Surgeon. Her website is

This article was published on November 16, 2016.


24 responses to “Flu Shots: Facts & Fallacies”

  1. Jenny H says:

    Better than getting a ‘flu shot’ which usually makes you sick for a few days afterwards at least, and may of may not protect you from the viruses going around that season, better to tell people who are sick to STAY HOME.
    Do NOT “soldier on” with medications. As I start make it illegal to advertise cold and flu remedies that purport to allow you to ‘soldier on’.
    If you are snotty and need to use a handkerchief every few minutes do NOT go to work, especially as a check-out chick.
    Do NOT catchy public transport.
    Do NOT send sick kids to child care/kindy/school just because you “need” to work.
    (There is a LOT to be said in favour of one ‘stay-at-home parent’ for young families! Do NOT fund child-care facilities with tax payer money. Pay stay-at-home, full time parents to be able to stay at home. This of course would also help solve the overproduction of junk stuff (we MUST have fill employment) an in doing so benefit the planet!)
    Do not go out and do the shopping.
    Do NOT sneeze into your hand and then handle shopping trolleys or other goods on shelves etc.

  2. Guerilla surgeon says:

    I once lost about 10 pounds in a week when I had the flu. I got so weak that I got out of breath washing myself in the shower. I was young then, I’d hate to get it now that I’m old. I suspect that many of the people who are against vaccinations have never had it. If they had, they wouldn’t be quite so anti-.

  3. Marja-Liisa Haverinen says:

    I never had influenza I’ve never had the shot either. But that is not the point, because I could get the flu someday. My problem with it is that those shots are so uneffective (allthou not entirely). They give false sense of security to workers like me who work in the hospital. That fore it might happen that we don’t protect ourselves in other ways as well as when we know that it’s possible to get the flu. For me I’m very carefull expecially in the flu season (using face masks, desinfection and so on..). It’s ok to give flu shots, but it is dangerous to market them as the fix of the problem.
    The unefficency is the main problem and it is not the first time that medical companies have distorted studies of the safety of medicine. For me it’s not worth the risk. But I have to add that I do this only with the influenza shots. I do get all the other shots when possible.

  4. Don Edwards says:

    I have a great deal of respect for this person based on other articles she has presented on eSkeptic

    I’ll get the damn flu shot

    I’ll also copy my wonderful wife who had suggested I might benefit.

    Don Edwards

  5. Elena Maksimova says:

    Excellent article!
    Some people will not change their opinions regardless of evidence, but through educational efforts like yours there is hope the message will reach more people in future generations.

  6. Mark says:

    All flu shots used to contain Mercury, Now they contain aluminum oxide, which is even worse. Any heavy metals in your blood cause’s cancer. That’s why many people have their fillings removed. Many cancer patients get kelation theropy done. I do think other people should get the vaccination, just to keep me safer. Maybe at 70 I would start myself. A young healthy person should not do it.

    • Harriet Hall says:

      The aluminum in vaccines is not known to have ever caused harm. Cancer is not a concern. Removing fillings is done for bogus reasons and actually exposes patients to mercury during the procedure. Chelation has very specific limited indications; many people are getting it for bogus reasons. The young, healthy people are the ones most likely to die in a flu epidemic. Both young and old benefit from flu shots.

  7. John Persichilli says:

    I can attest to the following, and I quote, “Children are the primary source from which influenza spreads through the population.”

    I was a teacher for over 30 years in the public school system. I almost always got a flu shot. One year I didn’t get one and sure enough I got the flu. The flu led to pneumonia which took months to get over from.

    Perhaps teachers should be immunized with a flu shot as a condition of employment. I guess that wouldn’t be possible…

  8. john ward says:

    I have had the flu vaccination for many years. I have alcoholic liver disease and after a year of abstinence suffered a very serious oesophageal bleed the day after my ‘flu jab. Very recently a friend died of a heart attack three days after vaccination. I fully understand that correlation is not causation (and was vaccinated again myself this year with no problems). But I also understand that when these things happen it is very difficult indeed to persuade the public to accept the co-incidence argument. Especially when the mass media don’t seem to understand it either. I fear the educators and statisticians are fighting a losing battle.

  9. skeptonomist says:

    If the shots really don’t reduce all-cause mortality then there is not much justification. It’s the mortality – among old people and other susceptible groups – that makes the huge research and deployment expense justified. Of course the controlled trials may not have much bearing on this question since it would be unethical to expose people who are really susceptible to the virus. That is, trials have probably been on healthy subjects who would not only be at a low risk of death but may also be resistant to the virus. Also the numbers involved in tests may not have been great enough to really measure the presumably small risk to the population of the particular strains involved.

    All strains are not the same. A really bad epidemic such as that of 1919 attacks relatively healthy people. It’s very hard to assess the risk of something like that beforehand.

  10. Terry says:

    I am allergic to eggs, so avoid flu shots that are produced on eggs. Is there an egg-free version? The nasal spray?

    • Harriet Hall says:

      One vaccine, Flublok, is egg-free. And current recommendations say that patients with egg allergy can be vaccinated with any inactivated vaccine.

  11. Bill Morgan says:

    I’m 72 years old. Prior to 1985, I got the annual flu shot and still got the flu. I stopped getting flu shots in 1985. I have now gone 31 years without the flu. How can a Doctor explain this to me? My current Dr. says he is baffled and can not explain this to me. I have not even had a cold in 31 years. Who can scientifically explain this to me?

    • Tom Dale says:

      My wife and I suffered the flue together in the winter of 1986. We watched her son play in a state basketball final on TV. It turns out that he has never got the vaccine. We both get the vaccine every year. He recently suffered a severe case of the flu. I suspect that he will begin getting the vaccine each year now!! Having the flu is a real waste of time.

    • Ron Jette says:

      Maybe you are just one lucky dude, Mr. Morgan.

      I used to work at a national organization whose main fight was with Big Tobacco. Every once in awhile, I would run into someone in his 80s who would proudly claim that he had been smoking for more than 60 years without a problem.

      How do you explain that? Same thing. Some people just defy the odds.

      • skeptonomist says:

        If you don’t die from tobacco (or the flu either) you are not defying the odds – they are still against death from any particular cause. The odds are in favor of dying from one of the many causes, not any given one of them. Only if you didn’t die would you be defying the odds.

    • bruce says:

      There is no, never was, a guarantee that you won’t get the flu if you get a shot nor that you will get the flu if you don’t. You may still transmit the flu. Not really sure what your point is. You’re talking about a single individual case among hundreds of thousands.

    • Bob Pease says:

      Nobody CAN explain it to you.

      Your assertion seems to be that since stopping the shots you got no more flu is proof that the shots might cause flu so everyone should follow your advice.

      Unfortunately the shot-quitters who got the flu have not been polled about their opinion on this matter.

      “science” plays odds after examining the consequences

      It is actually more interesting that the reason ing here seems to be that a lot of folks are hoodwinked but you where able to see through the fog.

      A lot of times this is in fact ,true

      RJ Pease

    • Phil says:

      Bill, You’re just lucky. I haven’t won the lottery yet, how can the scientific community explain that without resorting to a load of statistics.

    • Dave Rockwell says:

      It is an anecdote. Means absolutely nothing scientifically.

  12. Peter Whyte says:

    At any specific time, are different vaccines required and made available for different regions? Is there any chance of getting the vaccine for a flu that has not arrived, or which has passed by?

  13. Peter J. Seymour says:

    Here in the UK, those 65 and over can get the vaccination free of charge each Autumn. I get the impression that many people at least in the more science-orientated community understand the it is not 100% effective for the individual and that its effectiveness varies each year. (I can’t speak for those who decline the opportunity except that some say they are too busy to get it done). But many see it as a wise precaution. Apart from oneself, it lessens concern about mixing with elderly and children. In my case there is also a possible genetic concern in that my family tree shows some members in previous generations had a cause of death given as influenza.
    So, a good article.

  14. Kevin McDonald says:

    Excellent article. I will distribute it widely. It covers all the objections unenlightened people typically make. Thank you!

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