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Flu Vaccine Risks and Benefits

Compare the risks and benefits of the flu vaccine side-by-side and decide for yourself if flu vaccines are a good idea. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video. Created by Stanford School of Medicine.

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  • hopper cool style avatar for user Christi
    One risk that I didn't see listed there was the risk of having an asthma attack for people with asthma. Is this risk really so rare that it's not worth mentioning?
    (6 votes)
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    • male robot hal style avatar for user Benjamin C Short
      In the video "2 Types of Flu Vaccine" The lady said that she would keep referring in all following videos to the flu shot in the form, inter-muscular injection, which carries little to no risk including people with asthma. She did mention that the nasal injection flu shot creates a greater risk for asthma people and other groups.
      (17 votes)
  • marcimus pink style avatar for user Eugene Peskin
    "No flu" and decline both in hospitalization and deaths are stated as benefits. Strangely Cochrane Research which is an utmost authority in evidence-based medicine says that "There is little clinical evidence that the vaccines have an effect on things like hospital stay, time off work, death in healthy adults or even those with conditions like asthma and cystic fibrosis...Vaccines given to children under the age of two have the same effect as if they were given a dummy drug." (Thomas Jefferson, vaccine group coordinator as quoted in Guardian http://www.theguardian.com/society/2006/oct/27/health.medicineandhealth2). Quick research shows that position was reflected in various medical publications, such as "Influenza vaccination: policy versus evidence", British Medical Journal, BMJ 2006;333:912. I am confused, this totally contradicts data in the video.
    (6 votes)
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    • spunky sam blue style avatar for user L
      There are definitely policies in medicine, especially in the U.S., which show a disconnect between peer-reviewed, high quality research and the policies advocated by various medical groups. Those groups' own journals sometimes have the research in them, but the individuals and medical providers do not follow the evidence or link it with any changes in practice, or if they do, the changes lag far behind the release of the research. These groups include some of the largest and most-trusted groups in the field.
      I really like what I have been able to read from The Cochrane Collaboration--very enlightening! I encourage you to check out their website. You might be interested in this article, which is along the same lines as your question, and includes information about flu vaccines' research:
      (1 vote)
  • duskpin ultimate style avatar for user Rebekah
    I saw that no flu was one of the benefits, but is this really true? I got the flu shot last year, yet I later got the flu, twice! Is this really beneficial?
    (5 votes)
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  • aqualine ultimate style avatar for user seema nayak
    I have asthma, so I cannot take the Mist. Why is this? Would the Mist affect my already tight airways?
    (4 votes)
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  • primosaur ultimate style avatar for user Lo var Lachland
    why does flu cause death?
    (1 vote)
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Video transcript

Female Voiceover: Let's say a patient comes in the clinic and they're trying to decide if they want to get the flu vaccine. As with any decision, they're probably going to weigh the risks and the benefits of the flu vaccine. As healthcare workers, it's really important that we understand these risks and benefits so that we can talk to our patients about it and help them make an educated decision. So let's start out by thinking of the more common risks and benefits. With the flu shot, the most common risk is going to be pain at the site of injection or muscle soreness wherever the patient receives the intramuscular injection. For some patients, particularly those who are afraid of needles, you also might hear reports of lightheadedness after receiving the flu shot. So although these are the more common risks associated with the flu vaccine, let's remember that they're not experienced by everyone. Not everyone thinks that the flu shot hurts. Not everyone is sore the next day and certainly not everyone feels lightheaded after getting the flu shot. For patients who are particularly concerned about this, if available you can offer them the nasal spray, Flumist. This provides the same protection against flu without using needles. Let's counter these common risks with the common benefits of the flu vaccine. The most obvious of which of course is you have a decreased chance of getting sick with the flu. For patients who are particularly pain averse, they don't want to get the flu vaccine because they think it's going to hurt, I would counter this by saying, "You know what? Flu hurts a lot. "You're stuck in bed for days. It's completely miserable, "and if I was a patient making this decision, I would go with the flu shot "in this case because I would rather have soreness in the arm "for a few days than be stuck in bed for three to five days." Let's turn our focus now to some of the more rare risks and benefits. In 1976 there were reports of muscle weakness after patients were getting the flu vaccine. We found out that this was because of something called Guillain-Barre Syndrome. Guillain-Barre Syndrome is a nerve problem that leads to muscle weakness and although there was never any proof that the flu vaccine actually caused Guillain-Barre, since 1976 we've been screening for this condition to make sure that it doesn't lead to severe complications. In contrast to this rare risk, we have some less common benefits associated with the influenza vaccine. That is a decreased chance of hospitalizations and a decreased chance of death as a result of complications of the flu virus. So if you remember from before, flu can cause up to 200,000 hospitalizations every year, and anywhere from 20 to 40,000 deaths every year. So again, if I was a patient trying to make this decision based on these more rare benefits and risks, I would go with the flu shot in this case as well. Because I would much rather avoid hospitalization and death if at all possible. So these are some considerations to think about on an individual level. Another important consideration is the impact that the flu vaccine has on the community. What happens to this patient's family members or their coworkers, or classmates if your patient is a healthcare worker. How does the flu vaccine affect their patients? Well, there is no risk involved in getting a flu vaccine when you think about it from the perspective of a family member. If you get vaccinated it's not going to affect your family member in a negative way. It can really only affect your family members in a positive way. That's because if you're less likely to get infected by the influenza virus, you're also less likely to spread it. We call this herd immunity. Herd immunity protects those around you, your close contacts and as a result it's definitely a benefit of becoming vaccinated. So when we think about all of these benefits together, I think it's pretty clear to see the benefits outweigh the risks and that getting vaccinated against the flu virus is a good decision.