Can you get sick from the flu shot

With flu season upon us, the flu shot is your best available protection against the flu. Even though the dominant flu strains are constantly changing every year, getting the flu shot still lessens the risk of severe illness from any strain of the flu.

Getting the flu shot not only protects you, but it also protects those around you and your loved ones. If you are pregnant or have a baby, getting the flu shot can help keep you healthy and reduce the risk of spreading the flu to others.

Because of this, the Centers for Disease Control and Prevention (CDC) recommends an annual flu shot for everyone six months of age and older to reduce the risk of illness and prevent the spread to others.

If you are concerned about the potential side effects of the flu shot, speak to a trusted medical doctor for personalized guidance.

Flu shot reaction in adults

Flu shot side effects are possible but are generally mild. The most common side effects in adults include:

  • Fainting (in rare cases)
  • Fever
  • Headache
  • Muscle aches
  • Nausea
  • Swelling/redness around the injection site

Some studies have found a potential small link between the flu vaccine and Guillain-Barre syndrome (GBS). This is a rare disorder where the body’s immune system attacks the nerves of the body, leading to paralysis in some severe cases. 

The estimated risk is one to two cases of GBS per one million people vaccinated, and it is more likely to occur due to an infection like the flu rather than the vaccine itself.

Flu shot reaction in children

The reactions to flu shots in children are similar to those in adults. The main difference is that children are more likely to develop a temporary fever as a side effect than adults.

  • Body aches
  • Fainting (in rare cases)
  • Fatigue
  • Headache
  • Low-grade fever
  • Nausea
  • Soreness, redness, or discomfort at the injection site

In rare cases, if a child is allergic to one of the ingredients in the shot, they may have an allergic reaction to the flu shot. 

In the case of a fever, Tylenol can be taken. While flu shot side effects are possible, the benefits of flu vaccine protection outweigh the potential risks of infection.

Just like in adults, a child can’t get the flu from the flu vaccine.

Risks of not getting the flu shot

While there is a small risk of side effects from the flu shot, there are more significant risks associated with not getting it.

The CDC estimates that up to 20% of Americans will contract the influenza virus each year, and more than 200,000 will be hospitalized due to flu-related complications. Not getting the flu shot poses a bigger risk to overall health.

In particular, not getting the flu shot increases the risk of more severe illness, hospitalizations, and death in rare cases. This is especially true in those with compromised immune systems, such as pregnant women and the elderly.

Allergic reaction to flu shot

Some may experience a genuine allergic reaction to flu shot ingredients, which is different from the typical flu shot side effects mentioned above. In the case of a flu shot allergy, there are a few specific signs to look out for, especially if you or a loved one has never received the flu vaccine before:

  • A rapid heartbeat
  • Difficulty breathing
  • Dizziness
  • Hives
  • Hoarseness
  • Paleness
  • Swelling around the eyes or lips
  • Weakness
  • Wheezing 

Any of these signs may indicate an allergic reaction to the flu shot and require immediate medical attention. Those with egg allergies or who are allergic to certain other ingredients in the vaccine are more likely to develop a reaction.

In these cases, ask your doctor about an egg-free or alternative vaccine as a safe option.

Why does it feel like I have the flu?

Some people may experience symptoms after the flu shot, and many mistake it for the flu. It’s important to remember these flu shot symptoms are the body’s normal immune response to the inactivated virus in the vaccine and do not represent an actual flu infection. 

If you experience any side effects such as fever, headache, nausea, fatigue, or faintness, they are typically much less severe than the actual influenza virus. They usually only last one to two days and resolve on their own. 

To reduce the risk of flu shot side effects, drink plenty of water and take acetaminophen or ibuprofen for prevention.

Common flu vaccine myths

Despite what the research shows, a few common flu shot myths persist. Many wonder, “Can you get sick from the flu shot?” among other myths such as:

  • The vaccine causes autism.
  • I’m healthy and don’t need one.
  • I’ve gotten the flu shot before, so I don’t need another. 
  • The flu shot doesn’t do much.
  • I’ll wait until I get the flu to get a shot.
  • The vaccine causes infertility.
  • The vaccine can overload your immune system.
  • The vaccine contains toxins.
  • The vaccine gives you the flu.

Fortunately, none of these myths are backed by research. A flu shot does not make you sick and is recommended for everyone six months and older. If you have questions or concerns about the flu vaccine or a flu shot reaction, speak to a trusted medical professional who will discuss the facts and recommendations with you.

Flu shot FAQs

Here are some frequently asked questions about the flu shot:

How many days after the flu shot do you feel tired?

You may feel tired for a day or two after the flu shot, but many people do not experience any fatigue.

What meds should not be taken after a flu shot?

There are no harmful drug interactions with the flu shot, but it can change how some medications are metabolized. Speak to your healthcare provider if you are on any medication and plan on taking the flu shot.

Is the flu vaccine mandatory?

No, the flu vaccine is not mandatory but may be strongly encouraged for people in certain jobs.

When is the best time to get a flu shot?

You should get the flu shot at least two weeks before the start of flu season, which typically begins in October. September or early October is the best time to get a flu shot.

How long is a flu vaccine good for?

The flu shot protects you for about six months, which is why it is recommended that you get a new shot every year.

Does insurance cover the flu vaccine?

Most insurances cover the flu vaccine, but this can depend on your insurance plan. 

Visit an urgent care for your flu shot

Flu season is upon us, and one of the best ways to protect yourself from serious illness is by getting the flu shot and we are here to make it easy to get. To schedule your flu shot, find the center nearest you, walk-in today, or save your spot online. We are open seven days a week with extended hours, so you can get your shot when it works for you.

Written by Sarah Thebarge, Physician Assistant