Do People With Thyroid Disease Need a Flu Shot?

woman getting a shot
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Influenza, known as the "flu," is a viral infection of the respiratory system that can be severe, even life-threatening, for some people. The good news, though, is that influenza may be prevented by undergoing the flu shot.

Still, each year, people with thyroid and other autoimmune diseases question whether or not they should get a flu shot—and this is a reasonable question, especially considering that vaccines interact with your immune system.

While you should always check with your doctor for guidelines and advice regarding your own personal situation, here are some "flu facts" to keep in mind as you navigate this decision-making process.

Who Should Be Vaccinated?

According to the Centers for Disease Control and Prevention (CDC), routine yearly influenza vaccination is recommended for all people, ages six months and older (who do not have contraindications, like people with a history of a severe allergic reaction to the flu vaccine). 

The CDC states that "emphasis should be placed on vaccination of high-risk groups and their contacts and caregivers."

High-Risk Groups

These high-risk groups include:

  • All people aged 50 years or older
  • Children under five years old
  • Pregnant women
  • Residents of nursing homes and long-term care facilities
  • Extremely obese people (those with a BMI of 40 or more)
  • American Indians and Alaskan Natives
  • Children or teenagers receiving aspirin or aspirin-containing medications and who might be at risk for developing Reyes syndrome

The CDC also recommends the flu vaccine for people who have certain chronic medical conditions, such as:

  • Asthma
  • Chronic lung diseases, such as chronic obstructive pulmonary disease [COPD] and cystic fibrosis
  • Heart diseases, such as congenital heart disease, congestive heart failure, and coronary artery disease
  • Neurological and neurodevelopmental conditions
  • Blood disorders, such as sickle cell disease
  • Endocrine disorders, such as diabetes mellitus. (Note that thyroid disease all falls into the category of an endocrine disorder).
  • Kidney disorders
  • Liver disorders
  • Metabolic disorders

Lastly, people with a weak immune system due to disease or medication (such as people with HIV or AIDS, or cancer, or those on chronic steroids) should undergo the flu shot.

What Is the Flu Vaccine?

The injectable flu shot is made up of an inactive flu virus, which stimulates an immune reaction to the current strains of flu. It's essential to understand that the flu vaccine is made from dead influenza viruses (not live viruses), so it cannot possibly give someone the flu infection. 

To clarify, in some years, the live attenuated influenza vaccine (LAIV), known by its trade name "FluMist," was given to certain people—this vaccine (a nasal spray) does contain live, weakened virus.

However, the Centers for Disease Control did not recommend the LAIV nasal vaccine for the 2017-2018 flu season due to concerns over its effectiveness; although it looks like it will be included for administration in the 2018-2019 flu season.

What Does the Flu Shot Do?

The flu vaccine stimulates your immune system to produce antibodies against infection with influenza.

The flu shot not only helps prevents you from getting ill with the flu, but it also reduces your risk of being hospitalized or developing a complication (for example, getting bacterial pneumonia) if you do become sick.

Does the Flu Shot Sometimes Not Work?

If the inactive viruses in the flu vaccine for a particular season are not closely matched to the ones flowing around a person's community, the flu shot may not be as effective.

However, keep in mind, even if not closely matched, the flu shot is still giving you some protection (in other words, some "flu-like" antibodies are likely better than none).

Are There Side Effects from the Flu Vaccine?

Like with taking any medication, there is a chance that a person will have a reaction; however, if a reaction does occur, it's generally mild and short-lived, lasting about one to two days after the shot is given.

Minor problems associated with the flu shot include:

  • Soreness, redness, or swelling where the flu shot was given
  • Hoarseness and cough
  • Sore, red or itchy eyes
  • Fever 
  • Aches, including a headache
  • Itching
  • Fatigue

While extremely rare, serious reactions may occur with the flu shot. One serious risk associated with getting the flu shot is Guillain-Barré Syndrome (GBS)—a neurological condition that causes mild to severe muscle weakness. 

Will the Flu Shot Impact My Autoimmune Disease?

The connection between vaccines and autoimmune disease is still fuzzy, mostly because it's complex, depending on many factors, such as a person's genes and the vaccine being administered.

With that, it might be easiest to consider both sides of the story when determining how the flu shot may positively or negatively impact your immune system. 

Positive

Vaccinations, like the flu shot, help prevent a person from getting the "flu" or from developing serious flu-related complications (if they do get sick). So the flu shot prevents infection, and infection may be what triggers a person's autoimmune disease to develop in the first place (or be the trigger of an autoimmune flare). 

There is also some scientific evidence that certain vaccines (not necessarily the flu shot) may help prevent the manifestation of autoimmune diseases, by altering a person's immune system in such a way that is protective.

Negative

Post-vaccine reactions, like the development of post-flu shot GBS (an autoimmune condition that affects your nervous system), suggest that vaccines can trigger autoimmunity.

With that, there is some concern that vaccinations may exacerbate a person's underlying autoimmune illness, including autoimmune thyroid conditions like Hashimoto's disease and Graves' disease.

A Word From Verywell

The puzzling vaccine-autoimmunity dilemma leaves many doctors, patients, and researchers scratching their heads.

In the end, there is no great answer, except to consider a person's individual situation, weighing the vaccine's benefit over its risk.

Although, when it comes to the flu shot, the benefit likely outweighs any risks (for the vast majority).

The bottom line is if you have a thyroid or other autoimmune disease, have an open, honest conversation with your doctor—it's sensible, and you will feel better afterward, knowing you are making an informed decision. 

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View Article Sources
  • Centers for Disease Control. (2018). "CDC Guidelines for the 2017-2018 Flu Season." 
  • Vadala M, Poddighe D, Laurino C, Palmieri B. Vaccination and autoimmune diseases: is prevention of adverse health effects on the horizon? EPMA J. 2017 Sep;8(3):295-311.