Health experts are warning that this year’s influenza outbreak could be the worst in a decade. That’s why public health officials are urging almost everyone to get a flu shot. Older people (those over 65) are cautioned that they may have weakened immune systems and are especially vulnerable to the consequences of influenza. They are told that a flu shot will reduce their chances of getting sick, and if they do catch influenza it will be less serious. It’s hard to resist such a pitch. Millions of seniors are signing up for their shots. How good is the evidence to support this public health message?
The most objective organization for analyzing treatments is the Cochrane Collaboration. It is an international network of over 28,000 people from more than 100 countries who scrutinize scientific data from all over the world. The independence and objectivity of the Cochrane reviewers allows them to assess the effectiveness of a variety of treatment strategies in a way that few other groups can match. The Cochrane investigators have carefully analyzed flu vaccines and come up with some startling conclusions.
In 2010 (the most recent analysis) the Cochrane Database of Systematic Reviews published a study titled “Vaccines for preventing influenza in the elderly.” The authors assessed 75 studies. The conclusions:
We don’t know about you, but we find that conclusion shocking. Physicians are told that they are supposed to practice “evidence-based medicine.” That means that they are supposed to rely on solid scientific data before recommending a particular treatment…such as a flu shot. And yet the best experts in the world state clearly that such evidence does not exist to support influenza immunization for those over 65.
What about everyone else? One of the reasons that public health officials also encourage younger people to get a flu shot is that it is supposed to provide “herd immunity.” In other words, if children and healthy adults get a shot, they are theoretically less likely to spread the flu to the most vulnerable in the population, namely older people and infants. So, how good is the evidence that flu shots do something meaningful for healthy adults?
An analysis published in The Lancet Infectious Diseases (Jan. 2012) produced disappointing results. Researchers combed the medical literature for studies published between 1967 and 2011. After reviewing over 5,000 articles they narrowed their evaluation to 31 of the very best studies. These trials actually confirmed influenza infection through culture or a more sophisticated laboratory test. In the gold-standard randomized-controlled trials, the pooled efficacy was 59%. There was surprising variability in effectiveness from year to year. In some years, effectiveness was as low as 16%, while in other years it rose to 76%.
The Cochrane investigators also reviewed all the published studies of flu vaccine effectiveness in healthy adults (people between 16 and 65 years of age). They analyzed 50 studies carried out between 1966 and 2010 (Cochrane Database of Systematic Reviews, Jul 7, 2010). The authors concluded:
Here is the “Plain Language Summary” of the results of their investigation:
Yikes! If the primary purposes for getting a flu shot are to avoid getting influenza and reduce the likelihood of developing complications (such as pneumonia) or spreading the virus to other people (such as senior citizens), then there is little evidence that these goals are achieved. If you read the summary carefully, you will discover that even with a perfect vaccine, 33 people would have to be vaccinated for one to person to avoid the flu. In our humble opinion that is not very impressive.
What are we to make of this confusion? The experts plea for better research to determine the true effectiveness of the influenza vaccine, especially in older people. How can public health officials encourage everyone to get a shot without excellent data to support their recommendations? Public health experts are hoping to get 80% of the American public vaccinated against influenza in coming years. People deserve convincing evidence that such an effort will be worthwhile.
This is not to suggest that vaccines in general should come under suspicion. The smallpox vaccine was responsible for the greatest public health achievement of the 20th century, the elimination of this deadly and disabling infection. Providing polio vaccine to all at risk of this virus should lead to a similar accomplishment early in the 21st century. Research evidence as well as experience demonstrates that the benefits of these vaccines greatly outweigh their risks. We’d love to see similar evidence on influenza immunization.
It may be that today’s modern flu vaccines really do work, meaning that they protect 80 to 90 percent of those who get a shot from developing flu symptoms and complications. But we won’t know that until objective research proves it. In the meantime, you are pretty much on your own. Ask your doctor to review the scientific literature to see whether she can find evidence of effectiveness and give you better guidance. We have provided links to the most complete data. We would welcome physician feedback.
We would also love your thoughts about the influenza vaccine. Do you always get a flu shot? Does it protect you? Have you ever gotten a shot only to come down with the flu anyway? Share your story below.

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  1. fbl

    RJM, you have a right to your beliefs so go ahead and get your shot but don’t force me and mine to do the same! We do have a few freedoms left in this country and I choose NOT to get a flu shot. Haven’t had the flu shot or the flu in almost 30 years! nor colds!
    People who are afraid of the flu need to do some homework and get themselves healthier. If you are unhealthy or have unhealthy habits even the flu shot won’t help…which is probably why so many people who get the shots get the flu anyway.

  2. Bg

    Had my last flu vaccine about 5 years ago. 1-2 hours later had a facial rash/flushing. Then 3 days later had an inflamed spleen. Staying away from the flu vaccs now. A nurse in the doctors office commented at the time that she used to work for a company that made the vaccines, and she would NOT take one. BG in NC

  3. RJM

    Agree! Moreover, you are receiving strains that are expected to become a serious epidemic (Bird Flu, Swine and NIHI again, etc and they are coming). This publication is simply scare tactics, and people should not be lied to, or have publications that have no replicated data to back it up.
    Equally tragic, people can be carriers and those who do not have the flu vaccines are spreading it and may harm the most vulnerable. Frankly, that is nothing but self-serving idiocy. This website has some merits, but this article is simply way off! The couple who run this have obviously never seen someone die from Influenza; I have!

  4. M.W.

    The flu shot is like virus protection for your computer; under average conditions it will work effectively, but if you are constantly exposed to the flu virus day in and day out, eventually some of those pathogens will get through your immune system and make you sick. Also, there may be an unknown strain of the virus floating around in the air for which the flu shot will not prevent. It is a gamble; you may or may not catch the flu. However, it is always wise to play it safe by getting a flu shot every year.

  5. Ed S.

    I am a 70 year-old white male (will be 71 in three weeks) and have had the flu shot every year since it became available, and have never had the flu. Like any vaccine, it is not 100% efficacious, but IMHO, it certainly reduces the risk.

  6. mbd

    I am 62 yrs old and have had a flu shot since 2007. I have not had flu since, nor have I had any bad colds. Prior to receiving the flu vaccine, I had throwing-up type flu once about every 2 or 3 years, and at least one bad cold every year. I always felt certain I was dying every time I had the flu.
    If flu vaccines prevent only one in 33 to 100 incidents of flu a year, I think it is still well worth people getting the vaccine. In terms of side effects, I have never had more than a very slight fever a day after a flu shot. There are younger people who do not get the shot and call in sick frequently where I work. We are exposed to numerous germs from all over the world, as we see hundreds of people a day and handle items they touch, as well as breathe the air they cough into.
    I am a hand-washer, citrus-eater, vitamin-taker, and committed to flu vaccine every year. I hope research continues and improves the predictability of which strains need to be included in the vaccine. I wonder what the excluded studies had to say….

  7. Liz

    I am 70, and I have never gotten a flu shot. I retired a year ago, and where I worked, the ladies were sick all through winter, flu shot or not. But I never got the flu. I feel the difference between them and me is I took (and still do) 3000 IU of Vita D3 daily. I also eat organic food and very little sugar. I also cook from scratch. And I get 8 hours of sleep per night.

  8. Liz

    I am 70 and have never gotten a flu shot. I retired a year ago and where I works the ladies were sick all through winter, flu shot or not. But I never got the flu. I feel the difference between them and me is I took and still do, 3000 IU of Vita 3 daily. I also eat organic food and very little sugar. I also cook from scratch. And I get 8 hour of sleep per night.

  9. jrldev

    I reside in California and a member of an HMO group. Every year there is a drive for every member over 65 to get a flu shot. I am now aged 81 and for years I follow their advice. Every years I got a shot – I reacted (using my own terminology) in a semi-negative way. Meaning that I fell a bit “under-the-weather” after the shot for a a couple of months. For the last 4 years I decided to avoid the “flu-shot” and have been noticed that by taking simple to do safety precautions live avoiding being in very large crowds an washing my hands after several contact – shaking of hands -with people in public I had also avoided being a victim of the flue epidemic. I no longer believe in the promotions of “flu drives; considering that several – not just a few – of my geriatric-age acquaintances did suffered from the flu even after receiving the shots at the proper time – meaning not when the already have suffered from flu symptoms.

  10. JM

    Clearly from the figures the benefits for individuals are modest, with those seasonal effectiveness studies showing 16-76% effectiveness, but the overall effect of the flu shot campaigns for society is enormous. Even 16% effectiveness cuts into the transmission rate. And if we are hit by a deadly flu, like the 1918-1919 pandemic, cutting into the transmission rate may save hundreds of millions of lives.

  11. kjo

    As a nurse I was forced to get a flu shot every year and in spite of this, I did have the flu a few times. Since retirement 6 years ago, I have not had a flu shot and refuse to get one and have not contacted the flu. I worked in a nursing home where every resident was given a flu shot and in bad flu years, they got sick anyway.

  12. cmc

    I have never, nor will I ever get a flu shot.

  13. dp

    Took the flu vaccine while working, mandatory. Got sick only one time after taking. after retiring, My husband was coming down with the flu and I felt sick with fever, raced to the dr. for Tamiflu on two different occassions. Tamaflu stopped it both times. (must be taken in the first 48 hours of onset.) Now that I’m retired, I guess i’ll take my chances.
    Worked with patients in the 70’s with Guillen-Barrea syndrome. Some died.

  14. PO

    My husband got the flu several years ago the same week as he got the flu shot. A couple of years ago, my friend’s mother suddenly went permanently blind a few hours after getting the flu shot.

  15. EM

    I had the flu shot once as an adult. Got very sick within a few days, and spent a good portion of that winter sick. Have not taken the flu shot since then, and have not had the flu. If I start getting an Upper Respiratory Infection during flu season, I use a homeopathic remedy and keep on moving. For years, I’ve been the “last man standing” in an office passing the flu around.

  16. RJZ

    Have been getting a flu vaccine yearly since the 70’s and only had the flu once in the late 70’s. I find getting enough sleep gives me a lot of immunity to diseases. Plus, I wash my hands a lot. I am a 68 y.o. RN.

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