Flu: The Other Deadly VirusPage 12 of 14

11. Make-Up of the Flu Vaccines 2021–2022 Season

The FDA recommends that the quadrivalent formulation of egg-based influenza vaccines for the U.S. 2021-2022 influenza season contain the following:

  • an A/Victoria/2570/2019 (H1N1) pdm09-like virus;
  • an A/Cambodia/e0826360/2020 (H3N2)-like virus;
  • a B/Washington/02/2019- like virus (B/Victoria lineage);
  • a B/Phuket/3073/2013-like virus (B/Yamagata lineage).

The FDA recommends that the quadrivalent formulation of cell- or recombinant based influenza vaccines for the U.S. 2021-2022 influenza season contain the following:

  • an A/Wisconsin/588/2019 (H1N1) pdm09-like virus;
  • an A/Cambodia/e0826360/2020 (H3N2)-like virus;
  • a B/Washington/02/2019- like virus (B/Victoria lineage);
  • a B/Phuket/3073/2013-like virus (B/Yamagata lineage).

Because flu viruses are constantly changing, it is not possible to predict with certainty which types of viruses will predominate during a given season. Flu viruses can change from one season to the next and can even change within the course of one flu season. Because of these factors, there is always the possibility of a less-than-optimal match between circulating viruses and the viruses in the vaccine.

Six Updates for the 2021–2022 Season

The 2021–2022 season includes these six updates (Grohskopf et al., 2021):

  1. All seasonal influenza vaccines available in the U.S. are quadrivalent.
  2. The composition of U.S. influenza vaccines includes updates to the influenza A(H1N1)pdm09 and influenza A(H3N2) components. U.S.-licensed influenza vaccines will contain hemagglutinin derived from an influenza A/Victoria/2570/2019 (H1N1)pdm09-like virus (for egg-based vaccines) or an influenza A/Wisconsin/588/2019 (H1N1)pdm09-like virus (for cell culture–based and recombinant vaccines), an influenza A/Cambodia/e0826360/2020 (H3N2)-like virus, an influenza B/Washington/02/2019 (Victoria lineage)-like virus, and an influenza B/Phuket/3073/2013 (Yamagata lineage)-like virus.
  3. The approved age indication for the cell culture–based inactivated influenza vaccine, Flucelvax Quadrivalent (ccIIV4), has been expanded from ages ≥4 years to ages ≥2 years.
  4. Administration of influenza vaccines with other vaccines includes considerations for co-administration of influenza vaccines and COVID-19 vaccines. Vaccines given at the same time should be administered in separate anatomic sites.
  5. Flu vaccination soon after vaccine becomes available can be considered for pregnant women in the third trimester. As previously recommended, children who need 2 doses (children aged 6 months through 8 years who have never received influenza vaccine or who have not previously received a lifetime total of ≥2 doses) should receive their first dose as soon as possible after vaccine becomes available to allow the second dose (which must be administered ≥4 weeks later) to be received by the end of October.
  6. Contraindications and precautions to the use of ccIIV4 and RIV4 have been modified, specifically for those with a history of severe allergic reaction (e.g., anaphylaxis) to an influenza vaccine. A history of a severe allergic reaction to a previous dose of any egg-based IIV, LAIV, or RIV of any valency is a precaution to use of ccIIV4.

    A history of a severe allergic reaction to a previous dose of any egg-based IIV, ccIIV, or LAIV of any valency is a precaution to use of RIV4. Use of ccIIV4 and RIV4 in such instances should occur in an inpatient or outpatient medical setting under supervision of a provider who can recognize and manage a severe allergic reaction; providers can also consider consulting with an allergist to help identify the vaccine component responsible for the reaction.

    For ccIIV4, history of a severe allergic reaction (e.g., anaphylaxis) to any ccIIV of any valency or any component of ccIIV4 is a contraindication to future use of ccIIV4. For RIV4, history of a severe allergic reaction (e.g., anaphylaxis) to any RIV of any valency or any component of RIV4 is a contraindication to future use of RIV4.

Vaccines for the 2021–2022 Flu Season

The following vaccine list is grouped by category.

  • Inactivated Influenza Vaccines (IIV4s) and Recombinant Influenza Vaccine (RIV4)
    • Quadrivalent IIVs (IIV4s)—Standard-dose—Egg-based
      • Afluria Quadrivalent
      • Fluarix Quadrivalent
      • FluLaval Quadrivalent
      • Fluzone Quadrivalent
    • Quadrivalent IIV (ccIIV4)—Standard-dose—Cell culture-based
      • Flucelvax Quadrivalent
    • Quadrivalent IIV (HD-IIV4)—High-dose—Egg-based
      • Fluzone High-Dose Quadrivalent
    • Adjuvanted quadrivalent IIV4 (aIIV4)—Standard-dose with MF59 adjuvant—Egg-based
      • Fluad Quadrivalent
    • Quadrivalent RIV (RIV4)—Recombinant HA
      • Flublok Quadrivalent
  • Live Attenuated Influenza Vaccine (LAIV4)
    • Quadrivalent LAIV (LAIV4)—Egg-based
      • FluMist Quadrivalent

Online Resource

For a table of approved influenza vaccines for the 2021–2022 season, click the link below.

https://www.cdc.gov/flu/professionals/acip/2021-2022/acip-table.htm

Source: CDC, December 10, 2021

 

Giving an Influenza Vaccination via Needle

Photo: Giving an Influenza Vaccination via Needle

Source: United States Navy. Public domain.