Did you know there isn’t just one “flu shot” every year? In the years I've been analyzing available options, there are usually nine different vaccines on the market in any given flu season.
If you request the "flu shot" at your local pharmacy or healthcare provider's office, you may receive any of the vaccines on the market. The vaccines vary in ingredients and preparation so it is important to understand your options if you choose to receive one once you've been provided all the information necessary to make your decision. I suggest calling ahead to find out which vaccines are available before your appointment. If your preferred vaccine is not available, choose another location.
Who Makes the Flu Vaccines?
Four pharmaceutical companies produce all of the flu vaccines in the United States market. They are Sanofi- Pasteur, GlaxoSmithKline, Seqirus, and AstraZenica. Cumulatively, they are projected to produce 173.5 million to 183.5 million doses of flu vaccine this season.
How Are Flu Vaccines Made?
Three manufacturing processes are used to produce the flu vaccines. They are egg-based, cell-culture based, or recombinant technologies. The viruses used are either live, attenuated (weakened), or inactivated (killed). Vaccines are available in multi-dose or single-dose vials. All vaccines produced this season will be quadrivalent, meaning they are designed to protect against four different influenza viruses.
Why does a mama need to know all this technical talk? I'll get to that below! For now, keep reading.
Egg-based manufacturing involves injecting live influenza virus into eggs for replication. The resulting fluid is harvested and the virus is attenuated or inactivated. It is important to note that egg-based vaccines may be less effective due to viral changes that occur during egg incubation.
Cell culture manufacturing uses mammalian cells such as canine kidney cells for viral replication to create inactivated virus vaccines. The virus is then harvested for vaccines.
Recombinant vaccines are produced synthetically by combining an influenza virus gene with baculovirus, which normally only infects insects. The virus is then injected into a worm host for replication and then harvested for vaccine production.
Multi-Dose Versus Single-Dose Flu Vaccines
Multi-dose vial vaccines are used on multiple patients and contain the mercury-based preservative Thimerisol. This means they contain 25 mcg of mercury per dose. Single-dose preparations do not require a preservative. This means they either do not contain thimerisol or that it has been filtered out. It is estimated that 93 percent of vaccines produced for the 2022-2023 flu season will be thimerosal-free or "thimerosal-reduced."
Why Does This Matter?
The EPA recommends limiting daily mercury intake to about .045 micrograms of mercury per pound. A person weighing 200 pounds could safely consume about 63 micrograms of mercury each week. Someone weighing 150 pounds could safely consume 47 micrograms. If you’re curious about mercury and why we should avoid it, this article is helpful.
How Are the Vaccine Virus Strains Chosen Each Year?
Flu vaccines are created to protect against the most prevalent strains that are expected to circulate each year. For the Northern Hemisphere flu season that is approximately October-May, this prediction is made in the preceding February. This means vaccines are produced each year based on a mere educated guess during the previous flu season. In 2021, flu vaccines were 27 to 44 percent effective, depending on the population studied. Efficacy ranges widely from 3 to 60 percent over time.
What Flu Vaccines Are Available This Year?
Like many other years, the 2022-2023 flu season will have nine vaccine options.
FluMist is an egg-based vaccine with live attenuated virus. It is approved for non-pregnant people 2 to 49 years of age. FluMist should not be given to children taking aspirin or anyone on antiviral medications. It is also a poor choice for those with asthma as it can cause wheezing and increases the risk of hospitalization. Historically, FluMist has performed poorly, with efficacy as low as 3 percent. The vaccine information sheet (VIS) can be found here.
Fluarix and Flulaval are both egg-based inactivated vaccines for people six months and older. Both are only available in single dose preparation.
Flublok single-dose is a recombinant inactivated vaccine and does not use eggs in the manufacturing process. It is approved for people 18 years and older. It is the only recombinant vaccine on the US market.
Fluzone egg-based inactivated vaccine is available in both single-dose and multi-dose vial preparations for people 6 months and older. It is also available in a high-dose preparation for those over 65.
Afluria egg-based inactivated vaccine is produced in both single-dose and multi-dose preparations. However, the single-dose for children is not expected to be available this year.
Fluad egg-based inactivated vaccine contains the adjuvant MF59 that stimulates pro-inflammatory cytokines. It is available in single-dose preparation for adults 65 and older.
Flucelvax inactivated cell culture vaccine is available in both single and multi-dose preparations for people 6 months and older. It is the only cell culture vaccine on the market this year.
What Is the Best Flu Vaccine Option for My Family?
From a toxin perspective, the single-dose preparations are a better choice due to the Mercury content of multi-dose vials. If you have an egg allergy, recombinant or cell culture vaccines are your only options. If you are vegan, you may choose not to receive cell culture or egg-based vaccines. This chart summarizes this year's vaccines very well. There are multiple land mines to navigate if you choose to receive a flu vaccine. Avoiding eggs, insect and canine kidney cells and mercury can get complicated.
What If I'm Required to Receive a Flu Vaccine?
If you chose not to receive a flu shot but your employer requires it as a condition of employment, you are entitled to submit an exemption. For guidance with this, contact the advocates at Wonderfully Made Wellness Sanctuary.
Is There Another Option?
Boiron Influenzium is a readily available homeopathic flu prevention for the entire family. Oscillococcinum can also be used for flu-like symptoms. should you become ill. This article is a very helpful description of usage for both of these remedies.
RELATED READ: Natural Remedies for Winter Wellness
I hope this guide helps you make an informed decision regarding the flu vaccine this year. As always, my goal is to provide thorough and accurate information to help you make the best possible educated choice for yourself and your family! If you would like to review previous year's article, visit my blog archive.