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Doctors respond to 20 common concerns about the flu shot

  • Doctors respond to 20 common concerns about the flu shot

    Every October, people return to a familiar conversation: Should you get the flu shot? As flu season begins in the Northern Hemisphere, this question—along with other concerns—circulates among families, and in schools and workplaces. “I heard it isn’t as effective this year.” “I was told you should wait until it’s colder.” “My friend got a flu shot last year, and she had a fever afterward.”

    There’s no shame in being concerned. The flu is a complicated disease caused by a family of influenza viruses. Each year, different variations of influenza circulate and become widespread globally. Flu experts at more than 100 influenza centers around the world keep track of these different variations, or strains, and go through an intensive research process to identify which strains may be the most common in a given season. This research process leads to the creation of the season’s vaccine, which is intended to protect against common flu strains that winter. But the seasonality of the flu leads to variation in both flu severity and vaccine effectiveness from year to year.

    While COVID-19 may be dominating the health conversation right now, doctors and other experts are urging Americans to consider flu vaccination as well. The flu has caused between 140,000 and 810,000 estimated hospitalizations and between 12,000 and 61,000 estimated deaths each year since 2010, according to Centers for Disease Control and Prevention (CDC). In 2020, experts are particularly concerned that the seasonal flu may become a burden for hospitals, which are already caring for an influx of COVID-19 patients. The flu and COVID-19 also have similar symptoms and can require similar equipment from hospitals and health labs, which makes a double epidemic even more concerning.

    In order to address flu concerns and help readers make decisions for themselves and their families, FindCare compiled a list of 20 common concerns about flu vaccination from friends, family, and online forums. Those questions were then sent to six doctors and epidemiologists, who responded based on their expertise.

    The experts consulted in this story are:
    - Emily Temple-Wood, D.O.; family medicine resident at Lutheran General Hospital
    - Jessica Malaty Rivera, M.S.; infectious disease researcher and science communication lead at the COVID Tracking Project
    - Lindsey Shultz, M.D.; physician, public health analyst, and expert contributor to COVID Explained
    - Josh Petrie, Ph.D.; assistant professor at the University of Maryland School of Public Health
    - Rachel Roper, Ph.D.; associate professor at the East Carolina University Medical School
    - Allison Messina, M.D.; chairman of the Division of Infectious Disease at Johns Hopkins All Children's Hospital

    Read on to learn more about how flu vaccination works and why experts consider it important.

  • How flu shots work

    - Question: How does the flu shot work?
    - Source: Emily Temple-Wood, D.O.
    - Answer: “I like to think of the flu shot—and vaccines in general—as target practice for your body. Our immune systems are infinitely adaptable but the main downside is that it takes time for them to learn how to fight different bugs, which means you usually get sick the first time you get exposed to something like the flu.

    “We can hack that system with vaccines, which give your body the information it needs to fight something off without getting you sick. The flu shot is what we call an inactivated (killed) virus vaccine—you can't get sick from the vaccine. When you get the shot, your immune system notices the dead viruses and makes antibodies against the dead viruses. Antibodies are what the body uses to fight infections, and they get better when you have already been exposed to something. So, if you've had the flu shot and get coughed on by someone who has the flu, your immune system has already seen the flu and has practiced killing it. That means that if you get sick at all, it'll be less severe.”

  • Illness from the vaccine

    - Question: Can you get the flu from the flu vaccine?
    - Source: Jessica Malaty Rivera, M.S.
    - Answer: “No, you cannot get the flu from the flu vaccine. Flu vaccines are made with inactivated (killed) viruses that cannot cause illness. For those who are vaccinated against flu and still get the flu during flu season, symptoms are often milder as a result of vaccination.”

  • Potential side effects

    - Question: What side effects should I expect?
    - Source: Lindsey Shultz, M.D.
    - Answer: “The most common side effects for the injected vaccine are tenderness, redness, or a bit of swelling at the injection site. While not everyone will get these, it's good to plan ahead for a few days of muscle soreness in whichever arm you get the vaccination just in case, so figure out which arm works will work out best for you—most people pick their nondominant arm. It's also possible to get a low-grade fever, headache, and nausea, though these should go away after a day or two. The nasal spray flu vaccine also has the potential to cause a runny nose, sore throat, and cough.

    “Serious adverse events are quite rare, and the risk profile is much lower than the risks you'd generally run from getting the flu itself. Contact your medical provider if you experience a high fever or signs of a severe allergic reaction like difficulty breathing, dizziness, or a rapid heartbeat. These signs would most likely happen within a few minutes to hours of getting the shot and can be remedied with medical treatment.”

  • Pain at the injection site

    - Question: Why will my arm be sore after getting the vaccine?
    - Source: Emily Temple-Wood, D.O.
    - Answer: “Your arm gets sore after the flu shot for a couple of reasons. The first one is that you got stabbed a little bit and any kind of poke hurts. The second reason is that your immune system is busy mustering that response to the killed viruses in the vaccine. This involves sending white blood cells to the area and increasing blood flow, which causes swelling as well.

    “The best thing to do for the pain and swelling is to relax your arm as best you can during the shot, and move your arm more afterward to get lymphatic flow moving. You can also use heat or cold packs, and over-the-counter pain medications if the pain is severe and your doctor says it's okay.”

  • Got sick once

    - Question: I got sick once after getting the flu shot! Why should I get it again?
    - Source: Josh Petrie, Ph.D.
    - Answer: “Many types of viruses cause cold and flu like symptoms, but the flu shot only protects against the influenza virus, which typically causes more severe disease. Getting vaccinated is the best way to protect yourself and others from influenza. You can not get influenza from a flu shot, but it is not uncommon to feel a little under the weather after receiving it. That means your immune system is responding to the vaccine and is a good thing.”


  • Fear of needles

    - Question: Can I get vaccinated if I don't like needles?
    - Source: Rachel Roper, Ph.D.
    - Answer: “Yes, there is a flu mist nasal vaccine. The flu injection/shot is a killed (dead) virus, but the flu nasal spray vaccine is a live attenuated virus. It is a severely weakened virus that will cause a small brief infection in your nasal passages. Most people don’t even notice it. The live flu mist often produces an even better immune response than the shot.

    “Because it is a live virus it could be dangerous for people who are immunocompromised, so they should not receive it. It is currently approved for people 2 to 49 years old. There’s actually a [CDC] list of who all should not get the live flu mist vaccine.”

  • Lack of health insurance

    - Question: How do I get vaccinated if I don't have health insurance?
    - Source: Lindsey Shultz, M.D.
    - Answer: “Without insurance, the out-of-pocket cost will typically be around $40 for the regular dose, with an added cost for a senior dose. Check with services like Blink Health or GoodRx to see if any discounts are available in your area. The CDC-backed site VaccineFinder will help you locate pharmacies.

    “There are also a number of options that provide free or discounted shots. Some schools and workplaces will hold events offering a flu shot to all members of their communities. Many county health departments also offer free or significantly discounted vaccines for people without insurance, or could provide you with more information about where to go in your community.”

  • Best time to get vaccinated

    - Question: When is the best time of fall/winter to get vaccinated?
    - Source: Emily Temple-Wood, D.O.
    - Answer: “The best time to get vaccinated is whenever you can—though October seems to be a pretty good, sweet spot for staying protected through the end of flu season, earlier is totally okay, too. Definitely don't wait if you have the opportunity! There's no such thing as too late, either, if you're being offered the flu shot: It's because there's still flu hanging around.”

  • Where to get a flu shot

    - Question: Where should I go to get a flu shot?
    - Source: Rachel Roper, Ph.D.
    - Answer: “Your doctor’s office, public health clinic, many pharmacies, and even some grocery stores. Everyone should have a primary care physician. If you have a physician, you can get help when you need it. If you don’t have a physician, it can be really difficult to find an appointment when you need one. Just go make an appointment with a physician for a check-up and flu shot so you will have an existing relationship with one where they have your info on file. It could save your life.”

  • Allergy to eggs

    - Question: I'm allergic to eggs, how does that affect me getting a flu shot?
    - Source: Josh Petrie, Ph.D.
    - Answer: “It shouldn't. The CDC recommends that people with egg allergy can receive any licenced influenza vaccine. However, there are vaccine options available that are not produced in eggs that you can discuss with your doctor if you're concerned or if you have had a severe reaction after receiving an influenza vaccine in the past.”