The Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices has issued new guidelines for the prevention and control of seasonal influenza with vaccines for the 2021-2022 season. In general, routine annual vaccination is recommended for all patients 6 months of age and older who have no contraindications and should be completed by the end of October.

As the influenza season will coincide with the ongoing COVID-19 pandemic, influenza vaccination will help reduce the prevalence of influenza illness and can reduce symptoms that might be confused with COVID-19.  Vaccination may also help prevent outbreaks that may further strain the healthcare system.

For the 2021–2022 season, all influenza vaccines are expected to be quadrivalent.

Egg-based influenza vaccines:

Cell culture-based inactivated and recombinant influenza vaccines:

  • Will contain hemagglutinin derived from an influenza A/Wisconsin/588/2019 (H1N1)pdm09-like virus, 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.
  • These include Flucelvax Quadrivalent (standard dose cell culture-based) and Flublok Quadrivalent (recombinant).

Updates to the guidance for this upcoming influenza season include the following:
  • The Food and Drug Administration approved the use of Flucelvax Quadrivalent (cell culture-based quadrivalent inactivated influenza vaccine) for children aged 2 through less than 4 years old.
  • Current guidance indicates that COVID-19 vaccines can be coadministered with other vaccines including influenza vaccines. Clinical considerations regarding COVID-19 vaccination should be periodically reviewed for updated information.
  • Recommendations on the timing of influenza vaccination have been updated:
    • Vaccination soon after vaccine is available should be considered for women in the third trimester of pregnancy.
    • Children who need 2 doses of influenza vaccine administered at least 4 weeks apart should receive the first dose as soon as possible to allow for the second dose to be received by the end of October.  
    • Early vaccination (July, August) should be avoided in nonpregnant adults unless there is concern that later vaccination might not be possible.
  • For persons with a history of severe allergic reactions (eg, anaphylaxis) to influenza vaccine:
    • Use caution when administering cell culture-based inactivated influenza vaccine to patients with previous severe allergic reaction to egg-based influenza vaccine, live attenuated influenza vaccine, or recombinant influenza vaccine.
    • Use caution when administering recombinant influenza vaccine to patients with previous severe allergic reactions to egg-based influenza vaccine, cell culture-based inactivated influenza vaccine, or live attenuated influenza vaccine.
    • In these instances, administration should be done in an inpatient or outpatient medical setting under supervision of a provider who can recognize and manage a severe allergic reaction; allergist consult may also be beneficial.
    • For patients who have had severe allergic reactions to cell culture-based inactivated influenza vaccine or recombinant influenza vaccine or to components within the vaccine, there is a contraindication for future use.

The full report, which includes guidance for influenza vaccination of specific populations (eg, children, pregnant women, older patients, immunocompromised individuals), and situations (eg, history of Guillain-Barré Syndrome, egg allergy) can be found here.


Grohskopf LA, Alyanak E, Ferdinands JM, et al. Prevention and control of seasonal influenza with vaccines: Recommendations of the Advisory Committee on Immunization Practices, United States, 2021-22 influenza season. MMWR Recomm Rep. Published August 27, 2021.