Is the Flu Shot Safe?

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Is the flu shot safe or effective
Wellness Mama » Blog » Health » Is the Flu Shot Safe?

There is no question that the presence of flu season each year and the vaccine created as a result have become hotly debated issues in the media, by bloggers and perhaps most fiercely, by moms.

Since I have often fit into high risk category number one in the past few years (pregnant women), and have children that fit into high risk category number two (young children), this is an issue I have spent many hours researching. I’ve compiled some of the research I have come across in researching this topic. Please note that I am not a doctor, and none of this is to be considered medical advice. I’m simply sharing information I found while researching this topic for my own family.

Also please note that any discussion involving vaccines can potentially become heated. I welcome *charitable and civil* discussion in the comments below. Any direct attacks or name calling will be banned. At the end of the day, we are all striving to make the most healthy decisions for ourselves and our families.

Terms, Defined

When referring to the flu, I am including all of the following in the definition:

Influenza, often referred to as “flu,“ is an infectious respiratory disease caused by type A or type B influenza viruses, which are present in the mucus membranes and secretions of the nose, throat and lungs. There are other viruses and bacteria associated with “flu-like” symptoms and it is estimated that about 80 percent of all flu-like illness that occurs every year during the “flu season” is not type A or type B influenza. Only lab confirmation can detect whether flu-like symptoms, including serious complications like pneumonia, are caused by influenza viruses or other types of viral or bacterial organisms.

When referring to the flu vaccine I am including the following:

Two types of influenza vaccines are available in the U.S.: inactivated injectable influenza vaccine and live attenuated influenza vaccine, which is inhaled through the nose,Inactivated, injectable influenza vaccines packaged in multi-dose vials contain the mercury preservative thimerosal but inactivated influenza vaccines in single dose vials are thimerosal-free or contain trace amounts of the mercury preservative. The live attenuated nasal influenza vaccine does not contain thimerosal. (as of the date of my research on the topic)
There are 16 different influenza vaccine products licensed in the U.S. marketed by different pharmaceutical companies. Some of these vaccines contain only the 2009 pandemic H1N1 influenza A virus strain. However, most seasonal influenza vaccines in the U.S. contain two type A influenza viruses and one type B influenza virus that are selected every year by the World Health Organization (WHO) and U.S. Centers for Disease Control (CDC) for inclusion in flu shots given during the current flu season.

What’s the Flu Vaccine?

The NVIC compiled a helpful list of links (from the FDA website) of the product inserts and specifics on the current flu vaccines:

Quadrivalent Vaccines – Nasal

Quadrivalent Vaccines – Injected

Trivalent Vaccines – Injected

  • AFLURIA by CSL Limited (Afluria) – Package Insert & Licensing Information, Category B
  • Agriflu by Novartis Vaccines and Diagnostics, Inc. – Package Insert & Licensing Information, Category B
  • FluLaval by ID Biomedical Corporation of Quebec – Package Insert  & Licensing Information, Category B
  • Fluarix by GlaxoSmithKline Biologicals – Package Insert & Licensing Information, Category B
  • Flublok by Protein Sciences Corporation – Package Insert & Licensing Information, Category B
  • Flucelvax by Novartis Vaccines and Diagnostics, Inc. ­– Package Insert & Licensing Information, Category B
  • Fluvirin by Novartis Vaccines and Diagnostics Ltd. – Package Insert & Licensing Information, Category C
  • Fluzone by Sanofi Pasteur, Inc.
    • Aluminum
    • Formaldehyde
    • Trace antibiotics
    • Aluminum — a neurotoxin that has been linked to Alzheimer’s disease
    • Triton X-100 — a detergent
    • Phenol (carbolic acid)
    • Ethylene glycol (antifreeze)
    • Betapropiolactone – a disinfectant
    • Nonoxynol – used to kill or stop growth of STDs
    • Octoxinol 9 – a vaginal spermicide
    • Sodium phosphate

      Pros & Cons of the Flu Shot

      Obviously, the upside of getting a flu vaccine should be immunity from the flu. Unfortunately, if the wrong strain is included in the vaccine, this won’t be accomplished. This article explains how this is not an exact science and how it is not possible to completely predict the strain or provide protection from it.

      It seems there are two safety issues with flu season: the flu itself and the safety of the vaccine. I set out to research if (a) the vaccine was effective and (b) if it was safe. Once finding this out, I also wanted to determine the risks of the vaccine in comparison to the risks of simply contracting the flu.

      Ironically, while pregnant women, elderly, small children and medical workers are thought to be high risk candidates for contracting the virus (and are therefore encouraged to get it), the research is still out on the safety of the vaccine for these categories.

      What are contraindications to the flu vaccine?

      Among high risk factors listed by the CDC and the vaccine manufacturers are anyone who:
      (1) is sick with a fever;
      (2) has an egg allergy;
      (3) has a mercury allergy;
      (4) has a history of Guillain-Barre syndrome.

      If immunosuppressed individuals receive the flu vaccine they may not get an adequate protective antibody response.

      Is Flu Vaccine Recommended for Children?

      One consideration with the mass use of flu vaccine in healthy children is the removal of natural antibodies to flu which are obtained from natural infection. The question of whether it is better for healthy children, who rarely suffer complications from flu, to get the flu and develop permanent immunity to that flu strain or it is better for children to get vaccinated every year to try to suppress all flu infection in early childhood is a question that has yet to be adequately answered by medical science.

      Although in the past the flu vaccine has not been recommended for healthy children, today vaccination of children between the ages of 6 months and 18 years is strongly recommended by the Advisory Committee on Immunization Practices (ACIP) of the CDC and New Jersey now requires influenza vaccine for daycare and kindergarten entry.

      Is the flu Vaccine Safe During Pregnancy?

      In years past, pregnancy was also a contraindication to flu vaccine but, today, the Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control (CDC) recommends flu vaccine for women more than 14 weeks pregnant.

      Influenza vaccines are Category B or C drugs, which means that adequate and well-controlled studies on pregnant women have not been conducted and it is not known whether these vaccines can cause fetal harm when administered to a pregnant woman or if they can affect reproduction capacity.

      The package inserts published by the flu vaccine manufacturers state that “Animal reproduction studies have not been conducted with influenza virus vaccine. It is also not known whether influenza virus vaccine can cause fetal harm when administered to a pregnant woman. Although animal reproductive studies have not been conducted, the prescribing health care provider should be aware of the recommendations of the Advisory Committee on Immunization Practices. The ACIP states that if used during pregnancy, administration of influenza virus vaccine after 14 weeks of gestation may be preferable to avoid coincidental association of the vaccine with early pregnancy loss.”

      Pregnant women should be aware that the flu vaccine contains Thimerosal, which is a mercury derivative. Mercury is toxic to the brain and has been found to be associated with brain damage and developmental delays in babies whose mothers were exposed to high levels of mercury during pregnancy.”

      No testing has been done on the effects of these vaccines, alone or in combination, on the unborn children of pregnant women who receive them, though:

      A recent study showed exposure flu viruses among women during pregnancy provoke a similar gene expression pattern in the fetus as that seen in autistic children.

      Another important point to consider when weighing the risks and benefits of the flu vaccine(s) is their effectiveness. There are no controlled studies that demonstrate any decrease in cases of the flu among those who have gotten the vaccine. The insert in the FLUVAL vaccine for the 2009-2010 formula specifically states:

      FLULAVAL is an influenza virus vaccine indicated for active immunization of adults 18 years of age and older against influenza disease caused by influenza virus subtypes A and type B contained in the vaccine. This indication is based on immune response elicited by FLULAVAL, and there have been no controlled trials demonstrating a decrease in influenza disease after vaccination with FLULAVAL.

      Additional Resources

      I highly encourage everyone to do their own research on this or any health topic. If you are interested in further reading, here are some of the resources I found helpful:

      National Vaccine Information Center page on Influenza

      More detail on the flu vaccine

      Flu Shot and possible link to Guillain Barre Syndrome

Katie Wells Avatar

About Katie Wells

Katie Wells, CTNC, MCHC, Founder of Wellness Mama and Co-founder of Wellnesse, has a background in research, journalism, and nutrition. As a mom of six, she turned to research and took health into her own hands to find answers to her health problems. is the culmination of her thousands of hours of research and all posts are medically reviewed and verified by the Wellness Mama research team. Katie is also the author of the bestselling books The Wellness Mama Cookbook and The Wellness Mama 5-Step Lifestyle Detox.


108 responses to “Is the Flu Shot Safe?”

  1. John Giffin Avatar
    John Giffin

    Only multi-dose vials of flu vaccine use thimerosal, so it’s easy enough to avoid. It’s not a threat anyway – thimerosal contains ethylmercury, which is cleared from the body far faster than methylmercury (which you find in fish). It doesn’t bioaccumulate. A lifetime of vaccinations will put less mercury and a less harmful form in your body than eating tuna once.

  2. Mary jo Avatar

    As you are aware…..these are crazy times and the decision to get a flu shot Or not get a flu shot can be very confusing. I wonder if have any reliable research on “who is at risk if they contract the flu?” Are there certain people (older) that need to look at the risk factors of contracting the flu?

  3. Sara Avatar

    I work in the ICU and every year I see people die from the flu. The ones who get the sickest are the ones that don’t get the vaccine. The flu vaccine doesn’t mean you won’t get the flu, it means you won’t get as sick from the flu if you do contract it, because your body has already mounted an immune response to it. I’ve seen otherwise healthy 30 year olds die from the flu. I always recommend it, and am required to get it every year myself. I have never had any negative effects, and none of the nurses or physicians who get it have ever had any negative effects that I’ve heard.

    1. Sherri Becker Avatar
      Sherri Becker

      Hi Sara, This is a personal question but I would like to ask you how is your memory. Being a nurse and receiving a flu shot every year, I assume that by now it is 2023 and your post was 2019, you have received 4 more doses since this post, have you noticed any affects to your memory? The adjuvants in those vaccines you received cross the blood-brain barrier and must settle there, so I am curious to know if there has been an affect on your memory as of today, December 2023. Thank you if you decide to answer honestly. Blessings to you for your work. Sherri

  4. Lynne Roue Avatar
    Lynne Roue

    I have had flu just once in my life and that was 19 years ago. I am 65, I have slight Asthma and I remember sitting (I could only sit as I coughed so much and couldn’t breathe even if reclining) and realised I could imagine dying from Flu. After that my doctor advised the flu jab. I had it for three years, each time I had slight cold symptoms after. I haven’t had the jab since, I hope I never get flu again. I am not against inoculation but (rightly or wrongly) in THIS case I have decided that its not a 100% protection and might possibly actually be harmful though I might change my mind in the future.

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