What is in a Flu Vaccine? Understanding What Goes in Your Body

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What is in a Flu Vaccine? Understanding What Goes in Your Body

As the flu season draws near, you should be planning when to get your annual flu shot. It’s vital that we reduce the spread of respiratory diseases because of the ongoing pandemic. And the best way to protect yourself and your loved ones against influenza is to get vaccinated.

The flu virus is always changing. It’s one of the flu vaccine facts people must know. It’s nothing to become alarmed about as researchers are always working to update the flu vaccine. This article will answer some of the common questions about it.

Why Get Flu Shots?

Many people believe the flu is the worst type of cold. While it might seem that way, the reality is the flu can be deadly. According to the CDC, an average of 36,000 people died from the flu every year in the last decade. The number wasn’t so bad last year since more people were wearing masks. This has reduced virus transmission. But doctors believe the number of people getting the flu will go up again. This is due to the country returning to normalcy. Getting the flu shot means you won’t be part of that demographic.

There are other reasons to get a shot, like:

· You won’t spread the virus to the people around you.

· It will lower the odds of getting brought to the ER with flu-related illness.

· The symptoms will be less severe.

· It will prevent children from dying from flu-related complications.

What’s in Your Flu Vaccine?

Why Get Flu Shots | Well Health Works

Viruses are always mutating. Scientists work hard to be a step ahead of the latest variant. They develop a different iteration of the current flu shot to achieve this.

What’s in a flu vaccine? That’s one of the questions people always ask their doctors. Each vaccine has several components. The flu vaccine carries a mix of the four most common strains of influenza. It also contains a combination of antibiotics, preservatives, and sugars.

So how does the flu vaccine work if the virus is part of its components? While it does carry strains of the influenza virus, they’re deactivated. They won’t cause you to be sick. A vaccine works by introducing a modified version of a bacteria or virus. This is to give the body a chance to fight off the virus.

The recipe for a flu shot is quite complicated. Here’s a quick breakdown of the ingredients and their purpose:

Flu Virus

Vaccines contain small amounts of the virus they’re protecting people from. The flu virus in your vaccine is inactive or dead. It won’t cause you to get sick, but it will trigger your immune system to produce antibodies.

Flu shots are three-component vaccines. They will protect you against three viruses. These are the strains scientists believe will be prevalent during that year’s flu season. For 2021, they are –

· Influenza A HiN1 (Guangdong-Maonan strain)

· Influenza A H3N2 (Hong Kong strain)

· Influenza B (Washington strain)

Aluminum Salts

Aluminum salts assist the body in developing a strong immune response to the virus. The salt is an adjuvant. They make it possible for small amounts of the deactivated flu virus to be present in the vaccine. Aluminum salts are not always used in flu vaccines though. There are some iterations of the vaccine that are aluminum-free.


Antibiotics stop bacteria from growing in the vaccine. Manufacturers don’t use penicillin or other antibiotics that cause intense reactions. Neomycin or gentamicin is often used. The two are common ingredients in eye drops and topical medications.

Chicken Egg Proteins

These proteins are vital in the development of a flu vaccine. The deactivated virus used is often grown inside chicken eggs. The virus replicates in these proteins. The vaccine manufacturer then separates the virus from the egg.

The vaccine will contain trace amounts of egg proteins because of this. The amount is so small that people allergic to eggs can receive a flu shot without any problem. But those with several allergic reactions should receive the shot in a supervised location. They can also opt for egg-free flu vaccines.


Many people are often surprised to find that this chemical is in human bodies. It’s the product of a healthy digestive system. The chemical is toxic in large doses. But the amount of formaldehyde in the flu vaccine is very small. It’s used to deactivate the toxins from bacteria that might contaminate the vaccine.


This substance acts as a stabilizer in the vaccine. It protects the vaccine from damage caused by any freeze-drying or heat process. The gelatin ensures your flu shot is effective from the time it’s produced until you use it.


This preservative has been a component of vaccines since 1930. It’s derived from an organic form of mercury. It helps keep vaccines from becoming contaminated. The substance is only used in vials that hold more than one dose. It’s common for fungi and bacteria to grow in these vials, and this chemical prevents that from happening. Nasal sprays and one-dose vials aren’t at risk of contamination so they don’t need them.

Did the article help you understand vaccines better? You should also read this post on Recommended Vaccines for Adults.

Building a Healthy and Happy Workplace

Healthy and happy employees are productive employees. WellHealthWorks will help keep them that way. We are the top provider of wellness programs for a dynamic workplace. We have unique ideas when it comes to corporate wellness solutions. We’ve leveraged decades of experience to bring you convenient and affordable care packages. We offer COVID-19 employee testing and flu shots. We also do health screenings and biometric screenings. You can reach us at 833-935-9355 or at info@wellhealhworks.com.

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