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State of California—Health and Human Services Agency
California Department of Public Health

October 21, 2022

Dear Colleagues

Flu Vaccine 2022

Influenza (flu) season has arrived while COVID-19 and Monkeypox (MPX) are still circulating in our communities. People with HIV are at high risk of serious influenza-related complications. Getting the flu vaccine – both for people with HIV and for healthcare providers – is our best protection against the flu, as demonstrated in multiple clinical studies. Updated (bivalent) COVID-19 boosters, formulated to better protect against the most recently circulating COVID-19 variant, are now available and recommended. The COVID-19 vaccine and flu vaccine can be coadministered at the same visit. In addition, MPX vaccine (Jynneos) is also now recommended for all people with HIV. Ensuring that all of these vaccines are up to date for people with HIV is critical, as we all work to decrease acute illnesses in our community.

There have been several updates to the available influenza vaccine products (PDF) for this flu season, and the California Department of Public Health (CDPH) has updated its informational frequently asked questions (FAQ) on the use of these vaccines in people with HIV (see below). Flu vaccination is a covered benefit by all insurance providers and by California's AIDS Drug Assistance Program (ADAP). People with HIV who are uninsured or underinsured may also receive HIV care, including vaccinations, in Ryan White HIV/AIDS Program clinics. Let's utilize this benefit and protect even more people during the 2022-2023 flu season!

Please email me or Dr. Lily Horng in the California Department of Public Health (CDPH), Immunization Branch ( with any questions regarding the FAQ.



Philip Peters, MD

Office of AIDS Medical Officer

California Department of Public Health


Influenza (Flu) Vaccine "Frequently Asked Questions" for HIV Care Providers

1.    Should all people with HIV receive a flu vaccine?

Yes, all people 6 months of age and older who do not have contraindications should be vaccinated annually. People with HIV are a priority population for flu vaccine because they are at increased risk for severe influenza. Studies have shown that flu vaccination prevents illness and doctor's visits among people with immune suppression from HIV or other conditions, though may not work as well in people with low CD4 cell counts (less than 200 cells/mm3).

2.    Is it okay to administer a COVID-19 booster dose and a flu vaccine at the same visit?

Yes. COVID-19 vaccines and flu vaccines may be co-administered on the same day, including higher dose or adjuvanted flu vaccines. The benefits of co-administration and timely catch-up on vaccinations outweigh any theoretical risk. New data shows that immunogenicity and adverse event profiles are generally similar when vaccines are administered simultaneously as when they are administered alone (see "Coadministration of COVID-19 vaccines with other vaccines").

3.    What flu vaccines can be administered this season for people with HIV?

All FDA-approved flu vaccines can be administered at an age-appropriate dose for people with HIV, except for the live attenuated flu vaccine (Flumist), which is contraindicated in people with HIV regardless of age or CD4 count. All flu vaccines are quadrivalent, meaning that the vaccine protects against four strains, including two influenza A viruses (H1N1 and H3N2) and two influenza B viruses. In addition to standard products, high-dose and adjuvanted products are available for patients age 65 years and older. Most flu vaccines are manufactured with an egg-based process, but there are also egg-free vaccines using cell culture-based and recombinant formulations.

4.    Is a particular influenza (flu) vaccine brand or formulation preferred for people with HIV?

No. The Advisory Committee on Immunization Practices (ACIP) and the Centers for Disease Control and Prevention (CDC) do not recommend a particular vaccine as preferred for people with HIV. Any inactivated or recombinant flu vaccine that is age-appropriate may be used. Vaccination should not be delayed if a specific product is not readily available.

5.    Why can't the live attenuated flu vaccine (FluMist) be administered to people with HIV?

There is not enough safety and efficacy data for live attenuated flu vaccine use in people with HIV. In addition, there are alternative safe and effective flu vaccines available.

6.    Do people with HIV who are wearing a mask and washing their hands still need to get a flu vaccine?

Yes. Practicing everyday preventive actions are essential to protect yourself from COVID-19 and may help prevent flu illness. Getting a flu vaccine this fall is still necessary even when taking steps to prevent COVID-19. A flu vaccine will reduce the risk of flu illness even further, and among people who get the flu it reduces the severity of illness (lower risk of hospitalization and death).

7.    Should flu vaccine be given to a person with acute illness from suspected or confirmed COVID-19?

No. Vaccination should be temporarily deferred (postponed) for people who have acute illness with suspected or confirmed COVID-19. Flu vaccination can be administered once they have recovered from their acute illness and have met criteria to discontinue isolation. Mild illness is not a contraindication to flu vaccination, but vaccination visits should be scheduled after the isolation period is over to avoid exposing healthcare workers and other patients to COVID-19.

8.    What are the contraindications to flu vaccination?

Contraindications to flu immunization are rare. A history of a severe allergic reaction (e.g., anaphylaxis) to the vaccine or any of its components is a contraindication to the receipt of additional doses. Information about vaccine components can be found in the package inserts for each vaccine.

Immunization is safe for most patients with egg allergy (see "Persons with a History of Egg Allergy" section in the Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices — United States, 2022–23 Influenza Season: ( Moderate or severe acute illness or a prior history of Guillain-Barré syndrome within six weeks after receipt of influenza vaccination are precautions to influenza immunization, which means that the risks and benefits of immunization should be considered on a case-by-case basis.

9.    Tell me about the use of high-dose, adjuvanted, and recombinant influenza (flu) vaccines.

Adults aged ≥65 years should preferentially receive any one of the following higher dose or adjuvanted flu vaccines: Fluzone High-Dose Quadrivalent, Fluad, and Flublok Quadrivalent. Older adults are at increased risk for complications of flu, and vaccine effectiveness also decreases with age. These concerns have led to the development of products specifically for people aged 65 and over.

Fluzone High-Dose Quadrivalent is a quadrivalent, inactivated flu vaccine that contains four times as much antigen as standard-dose vaccines. A randomized trial conducted over two influenza seasons (2011–12 and 2012–13) among 31,989 people aged ≥65 years found that Fluzone High-Dose[1] was 24% more effective than standard-dose Fluzone.

Fluad is a quadrivalent, adjuvanted, inactivated influenza vaccine. An adjuvant is a substance added to a vaccine to increase the immune response. The MF59 adjuvant in Fluad is based on squalene, an oil that occurs naturally in many plants and animals. In a small observational study among older adults (65 years and older), Fluad was about 63% more effective than unadjuvanted inactivated influenza vaccine[2].

Flublok Quadrivalent is a recombinant, quadrivalent influenza vaccine that contains a higher dose of the influenza hemagglutinin antigen. It is approved for use in people 18 years of age and older. In a randomized controlled trial among 8,604 people aged at least 50 years during the 2014-15 season, the probability of influenza-like illness was 30% lower in those receiving Flublok compared to those receiving a standard dose quadrivalent inactivated vaccine[3].

10.    Should older adults, including older adults with HIV, preferentially receive the high-dose (Fluzone High-Dose), adjuvanted vaccine (Fluad), or recombinant (Flublok) influenza vaccine?

Yes, older adults with HIV should preferentially receive one of these three vaccines. If none of these three vaccines is available, then any other age-appropriate influenza vaccine should be administered.

11.    Are high-dose (Fluzone High-Dose) and adjuvanted vaccine (Fluad) recommended for people younger than 65 years of age?

No. Fluzone High-Dose and Fluad are licensed only for people age 65 years and older and are not recommended for younger people.

12.    Sometimes patients aged 65 years and older who have already received the standard-dose influenza vaccine hear about the high-dose (Fluzone High-Dose) or adjuvanted vaccine (Fluad) and want to receive those too. Is this okay to administer?

No. ACIP does not recommend that adolescents or adults receive more than one dose of influenza vaccine in a season. Only children aged six months through eight years who have never received influenza vaccine should receive two doses of influenza vaccine in a season.

13.    Where can I get more information and resources regarding flu vaccination for my patients?

The CDC has published its annual recommendations for influenza vaccination for the 2022-2023 influenza season (

The CDC also has a resource page for influenza vaccination for people with HIV, (

CDPH has additional resources to help prepare clinics to fight flu (

[1] Fluzone High-Dose study: Diaz Granados CA, Dunning AJ, Kimmel M, et al. Efficacy of high-dose versus standard- dose influenza vaccine in older adults. N Engl J Med 2014;371:635–45. [Note: study evaluated a trivalent version of the vaccine]

[2] Fluad study: Van Buynder PG, Konrad S, Van Buynder JL, et al. The comparative effectiveness of adjuvanted and unadjuvanted trivalent inactivated influenza vaccine (TIV) in the elderly. Vaccine 2013;31:6122–8. [Note: study evaluated a trivalent version of the vaccine]

[3] Flublok study: Dunkle LM, Izikson R, Patriarca P, Goldenthal KL, Muse D, Callahan J, et al. Efficacy of Recombinant Influenza Vaccine in Adults 50 Years of Age or Older. N Engl J Med. 2017 Jun 22;376(25):2427-36

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