The Centers for Disease Control and Prevention (CDC) recommends vaccination with any licensed, age-appropriate flu vaccine (with no preference expressed for any one vaccine over another) for the 2020-2021 influenza season.

There are many vaccines available which can sometimes be overwhelming and confusing. We have outlined a few of the commonly asked questions below. Remember, the most important thing is to get your influenza vaccination every year. This will help lower your risk of influenza infection and serious complications.

Why are there so many different types of influenza vaccines?
There are many variables between influenza vaccines including:
– The company that manufactures it
– The process by which the vaccine is manufactured
– The number of influenza strains (i.e. quadrivalent v. trivalent)
– The amount of antigen

The company that manufactures it:
There are many manufacturers (companies) that make influenza vaccines.
The manufacturer chooses a name for its vaccine and may choose to advertise for their product. You may have heard the following vaccine names: Fluarix, Afluria, Fluzone®. These are all standard dose inactivated vaccines, each made by a different company. There are 10 different influenza vaccines available in the US for the 2020-2021 influenza season.

The process by which the vaccine was manufactured:
There are many variables in the manufacturing process. Every vaccine that is created and available on the US Market is tested for effectiveness and safety, then approved by the FDA.

  • The most common influenza vaccine is the inactivated vaccine. This vaccine is made through an egg-based process in a lab where the viruses are grown, replicated (made into many copies), harvested and then killed (inactivated) and purified to create the vaccine. Note: although the process is egg-based, it does not mean people with an egg allergy cannot safely receive the vaccine. Talk with your provider about your type of egg allergy reaction to determine the safety.
  • The cell culture based vaccine does not use an egg-based process, but grows the viruses in mammalian (animal) cells instead of eggs. The Flucelvax® is the cell-based vaccine currently available.
  • Vaccines can also be made using recombinant technology, a process to make vaccines synthetically.
  • The Flublok® is a recombinant vaccine. Both the cell culture based and recombinant vaccines are good options for someone who requires an egg-free vaccine.
  • Some vaccines contain an extra ingredient called an adjuvant. For example, the Fluad vaccine is an inactivated vaccine that contains an adjuvant (MF59®) to help the body amount a stronger immune response. The adjuvant vaccines are approved for people 65 years and older.
  • Live, attenuated influenza vaccines are made through an egg-based process similar to the inactivated vaccine. However, for the live attenuated vaccines, the virus is not killed (inactivated) and instead the virus is weakened. This vaccine, called FluMist®, is given as a nasal spray.

The number of influenza strains:
A group of viruses (like the influenza virus) can have minor genetic differences. Each virus that is slightly different from the other virus is called a strain. Various strains of influenza A and various strains of influenza B are included in the influenza vaccines each year.

  • Quadrivalent means there are 4 influenza strains
  • Trivalent means there are 3 influenza strains

The CDC recommends the influenza strains that should be included in the vaccines each year based on the prediction of which influenza viruses may cause the most human illness that season.

The amount of antigen:
The antigen is the part of the vaccine that causes the human body to produce antibodies. This process of producing antibodies is the body’s “immune response,” gearing up to protect you from future exposure to the influenza virus.
The standard dose influenza vaccine contains 15 micrograms (mcg) of antigen. The Fluzone® high dose influenza vaccine contains 60 mcg of antigen and is approved for people 65 years of age and older. The is another vaccine called the Flublok® that contains 45 mcg of antigen.

Which vaccine should I receive?
Talk with your provider about which vaccine may be best for you considering your age and health status. Remember, vaccination is the most important part! We recommend the influenza vaccine to patients 6 months and older.* We can give you an influenza vaccine during your office visit or you can make an appointment for vaccination only

At Vibrant Health, we have two influenza vaccines available for the 2020-2021 season.

  • Fluzone®, an inactivated quadrivalent standard dose vaccine (contains 15 mcg antigen)
  • Flublok®, a recombinant quadrivalent vaccine (contains 45 mcg antigen)

If you prefer to get another influenza vaccine such as the FluMist® (live attenuated nasal spray) or Fluzone® High Dose (recommended for ages 65+), talk with your doctor about comparing your options. Some community pharmacies may have these available. Don’t delay your vaccination!

*If you have an immune system compromising condition, egg allergy, or are currently ill, talk with your provider about vaccination first.

Resource: Center for Disease Control and Prevention. Influenza (Flu): Prevent Seasonal Flu. September 28, 2020.