Different Type of Flu Vaccines

This is designed to protect against 4 different flu viruses, including 2 influenza A and 2 influenza B

High-dose flu vaccines are a type of vaccine approved for people aged 65 and older. They can help people in this age group have a stronger immune system response against influenza, commonly called the flu.

The flu viruses used in the cell-based vaccines are grown in cultured cells of mammalian origin instead of in hen’s eggs.

A jet injector is a medical device used for vaccination that uses a high-pressure, narrow stream of fluid to penetrate the skin instead of a needle. Jet injectors may be powered by compressed gas or springs. The devices were invented in the 1960s and were used successfully in mass vaccination efforts to prevent smallpox and other diseases. These devices have also been used to vaccinate members of the armed forces.

All nasal spray influenza (flu) vaccines for the 2023-2024 season are Quadrivalent, meaning they are designed to protect against four flu viruses: an influenza A(H1N1) virus, an influenza A(H3N2) virus, and two influenza B viruses. Some people should not get the nasal spray flu vaccine:

• Children younger than 2 years old

• Adults 50 years and older

• People with a history of severe allergic reaction to any ingredient of the vaccine (except for egg protein) or to a previous dose of any flu vaccine

• Children 2 through 17 years old who are receiving aspirin- or salicylate-containing medications.

• Children 2 through 4 years old who have asthma or who have had a history of wheezing in the past 12 months

• People with weakened immune systems (immunosuppression) from any cause

• People who care for severely immunocompromised persons who require a protected environment (or otherwise avoid contact with those persons for 7 days after getting the nasal spray vaccine)

• People without a spleen, or with a non-functioning spleen

• Pregnant people

• People with an active leak between the cerebrospinal fluid and the mouth, nose, ear, or other place within the skull

• People with cochlear implants

• People who have taken flu antiviral drugs within a certain amount of time (within the past 48 hours for oseltamivir and zanamivir, the past 5 days for peramivir, and the past 17 days for baloxavir).
  
  In addition, the following medical conditions are precautions to the use of the nasal spray flu vaccine:

• Asthma in people 5 years and older.

• Other underlying medical conditions that can put people at higher risk of serious flu complications. These include conditions such as lung disease, heart disease (except isolated hypertension), kidney disease (like diabetes), kidney or liver disorders, and neurologic/neuromuscular, or metabolic disorders. “People at Higher Risk of Developing Flu–Related Complications.”

• Moderate or severe acute illness with or without fever.

• Guillain-Barre Syndrome within 6 weeks following a previous dose of flu vaccine.

An adjuvant is an ingredient added to a vaccine that helps create a stronger immune response to vaccination. Fluad Quadrivalent is approved for use among people 65 years and older, who often have a lower protective immune response after flu vaccination compared to younger people.

Recombinant influenza (flu) vaccines are produced using recombinant technology. This method does not require an egg-grown vaccine virus and does not use chicken eggs in the production process.

The recombinant flu vaccine was first licensed by the FDA in the United States in 2013. Currently, the recombinant flu vaccine and the cell culture-based flu vaccine are the only egg-free flu vaccines licensed for use in the United States.

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There is one Quadrivalent recombinant flu shot (Flublok Quadrivalent) available this season.