Why You Should Get a Flu Vaccine

Father measuring temperature of his sick son
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​The flu is a highly contagious respiratory virus that circulates each year. It makes millions of people sick, hospitalizes hundreds of thousands and kills tens of thousands in the United States alone. We have a vaccine to prevent it yet many people still refuse the vaccine for a variety of reasons. Whether you "believe in" flu vaccines or not, you need to know why they are recommended for nearly everyone.

Why Flu Vaccines Are Important

It is well established that flu vaccines are the best form of protection we have against influenza - the virus that causes the flu. Although they are, unfortunately, less effective than many vaccines we have for other diseases, they still protect more people from getting sick with the flu than any other measures you can take to prevent illness. Washing your hands and staying away from sick people are important and helpful, but these things won't prevent the flu like the vaccine will. 

Influenza is a serious illness. The most common symptoms are cough, fever, body aches, headache, chills, and exhaustion. Some people may have mild congestion and a few will also experience vomiting and diarrhea. The symptoms may last anywhere from 2 to 7 days. Most people who get the flu recover but some—especially those in high risk groups—may develop secondary infections or become seriously ill with the flu.

We spoke with CDC Influenza Division Director, Dr. Dan Jernigan, about flu vaccines and why vaccination is important. When asked what he would say if he were trying to convince a friend or family member to get a flu vaccine, he replied "I would say that flu vaccines prevent illness and serious flu complications that can lead to hospitalization or death. I would say that getting a flu shot is an easy thing to do that can keep you from spending a miserable week in bed, or worse. I would say that I would hate it if something bad happened to them that I could have helped to prevent if I had been able to convince them to get vaccinated." 

Basic infection prevention strategies like hand washing are important year round to prevent illnesses. However, they won't protect you against everything. One reason flu vaccines are so important is because it is contagious before you know you have it. You can spread the virus and infect other people a full 24 hours before symptoms appear. Washing your hands and avoiding people after you start feeling bad won't prevent you from spreading the virus when you don't know you are sick yet. 

Who Is at Risk?

Certain groups of people are at higher risk for complications from the flu than others. Young children, older adults, pregnant women, and people with chronic health conditions such as asthma and heart disease are more likely to be very sick, hospitalized or lose their lives to influenza.

The nonprofit organization, Families Fighting Flu, works to educate people about the dangers of the influenza virus in children. In the United States, typically over 100 children die from the flu each year and a majority of those children did not get a flu shot. If you have never taken the time to read the stories of some of these families, you should. If you are a parent, it's unlikely that you can imagine anything worse than losing your child. The stories of these families who lost their children to the flu have are more powerful and convincing than any doctor or government agency could be. 

Dr. Jernigan points out that flu vaccination is really important for those in high risk groups. "Obviously CDC’s role is to prevent illness across the entire population, but there are people who are more vulnerable to very serious illness if they get infected with flu.  We try to reach out to those people especially to prevent those serious outcomes. For example, one of the saddest things about this job is to hear about children who have died from flu and were not vaccinated. Any child death is tragic, but a death that could have been prevented by vaccination is especially difficult. As a doctor and a father, I want to help prevent that as much as I possibly can. The same is true of pregnant women, or people with asthma, diabetes, or heart disease. If we could convey the fact that flu can be deadly and a vaccine can prevent serious illness to those people so that they would get vaccinated, then I would feel very good about my job."

Flu Vaccine Myths and Facts

Let's take a look at some of the myths that keep people from getting vaccinated and set the record straight. One of the most common excuses we hear is that getting the flu vaccine doesn't work. People say things like "every time I get the flu shot, I get the flu". While that may seem to be the case, it is highly unlikely that is what is happening. There are multiple reasons you may get sick after getting a flu vaccine

  1. You may not have the flu at all. There are a lot of other respiratory and gastrointestinal viruses that circulate during flu season. The flu vaccine only protects against influenza. It won't keep you from getting any other illness. However, a majority of those other illnesses aren't as dangerous as influenza is. 
  2. You got sick before the vaccine could take effect. Protection from a vaccine isn't instantaneous. It takes two weeks to develop immunity after getting a flu vaccine. So if you happen to be exposed either before or right after getting your flu vaccine, it won't protect you (yet). 
  3. You have a strain of influenza that wasn't included in the vaccine. Researchers do their best to guess which strains of influenza will be circulating the following flu season but they don't always get it right. The vaccine has to be developed and manufactured six months in advance. The influenza virus mutates frequently so if the strains of the flu that are making people sick aren't a good match to those included in the vaccine, you may still get it even if you've been vaccinated. However, research proves that a majority of people who get the flu after being vaccinated have milder symptoms and recover more easily than those who weren't vaccinated at all. So getting the flu shot is worth it, even when it's not a good match. 

    Have you ever thought or heard that the flu vaccine can actually give you the flu? That's not true either. The vaccine is made from a killed virus. Killed viruses cannot multiply in your body and make you sick. Vaccines work by "showing" your immune system what the bad germs look like so it can develop antibodies to fight those germs if they come into your body in the future. It's not scientifically possible for the flu vaccine to give you the flu. Even the nasal spray flu vaccine, which is made from a live attenuated virus, is inactivated, meaning it doesn't have the ability to multiply or cause illness in a healthy person. If you get sick after the flu vaccine, it's not because the shot made you sick. 

    Dr. Jernigan explains why influenza vaccines can be so confusing: "Influenza viruses are particularly tricky because they are constantly changing. It’s like the virus is trying to find weak points in our armor so that it can infect us and multiply inside us. We have to monitor thousands of different flu viruses to try to figure out a pattern of how the different viruses are evolving and which ones are likely to predominate. Then we need to find a virus that will work well for vaccine production and next create a vaccine virus to hand off to vaccine manufacturers.

    They then have a months-long process of production. The steps from detection, inspection, injection and prevention are many and complicated. A lot of things can go awry, including the viruses changing in ways that are completely unpredictable. That is just one of many factors that make flu vaccines scientifically challenging. The important thing to remember though, is that there are years of data to show that while flu vaccines can vary in how well they work, as a public health intervention, vaccination provides significant protection during most seasons. Last year, CDC estimates that flu vaccination prevented 5 million flu illnesses, 2.5 million flu-related medical visits and 71,000 hospitalizations. Some people might not think that 71,000 people seems like a lot but it’s enough people to fill every hospital bed in the state of Florida or Texas, which is pretty significant. Or imagine if just one of those people was your grandmother, child or pregnant friend."

    It is so important to understand that flu vaccination is not just about protecting yourself. There are millions of people that can be seriously affected by influenza. Even if you aren't one of them, vaccinating yourself and your family could quite literally save a life. 

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    View Article Sources
    • Get Vaccinated | Seasonal Influenza (Flu) | CDC. http://www.cdc.gov/flu/consumer/vaccinations.htm.
    • Take time to get a flu vaccine. Centers for Disease Control and Prevention. http://www.cdc.gov/flu/consumer/prevention.htm. Published May 25, 2016. 
    • VeryWell.com Interview with Dr. Dan Jernigan, CDC Influenza Division Director