• Q: What's new in the 2020–21 influenza vaccine recommendations?
• Q: Who is recommended to be vaccinated against influenza?
• Q: Which influenza vaccines will be available during the 2020–21 influenza season? 
• Q: What are the changes to vaccine viruses for the 2020–21 influenza season?
• Q: What are the new influenza vaccines available for the 2020–21 influenza season?
• Q: Which formulations of influenza vaccines are licensed for various age groups?
• Q: Does ACIP prefer that healthcare professionals administer high-dose or adjuvanted influenza vaccine to people age 65 years and older, or is standard-dose influenza vaccine acceptable?
• Q: When does CDC recommend starting influenza vaccination?
• Q: Should our practice consider revaccinating our high risk and older patients a second time during the year due to concerns with waning immunity?
• Q: Should Fluzone High-Dose Quadrivalent, Fluad (trivalent), or Fluad Quadrivalent be administered to patients younger than age 65 years?
• Q: Does ACIP recommend one influenza product over another for pregnant women?
• Q: Which influenza vaccines can we give to children?
• Q: Please provide details about the use of inactivated influenza vaccine in children younger than 3 years.
• Q: Which children younger than age 9 years will need 2 doses of influenza vaccine in this influenza season?
• Q: Can a clinic vaccinate children younger than age 3 years with influenza vaccine taken from a multi-dose vial of influenza vaccine? The multi- dose vials contain thimerosal as a preservative.
• Q: For whom is FluMist Quadrivalent approved?
• Q: Is administering FluMist an aerosol-generating procedure requiring airborne precautions during the COVID-19 pandemic?
• Q: What types of personal protective equipment do healthcare personnel need for administering vaccines?
• Q: What are contraindications and precautions for inactivated influenza vaccines?
• Q: What are contraindications and precautions for the recombinant influenza vaccine (Flublok)?
• Q: What are the contraindications and precautions for FluMist?
• Q: What is the latest ACIP guidance on influenza vaccination and egg allergy?
• Q: We are considering co-locating our COVID-19 drive-through testing site and influenza vaccination sites.  Can we vaccinate someone with suspected or confirmed COVID-19 infection?
• Q: Is it acceptable to draw up vaccine into syringes at the beginning of the day? If it isn't, how much in advance can this be done?  

Influenza Vaccination Questions & Answers for the 2020–21 Season

Q: What's new in the 2020–21 influenza vaccine recommendations?

A: The 2020–21 ACIP influenza vaccine recommendations were published on August 21, 2020, and are available at www.cdc.gov/mmwr/volumes/69/rr/pdfs/rr6908a1-H.pdf. The updated guidance describes the vaccine composition for this season (a change in the A/H3N2, A/H1N1, and B/Victoria lineage vaccine components); discusses the availability of two new vaccines for adults age 65 and older, Fluzone High-Dose Quadrivalent (Sanofi Pasteur) and Fluad Quadrivalent (Seqirus); updates recommended intervals between live attenuated influenza vaccine (LAIV4, FluMist Quadrivalent; AstraZeneca) and influenza antiviral medications; updates contraindications for LAIV4 to include cerebral spinal fluid leak, cochlear implant, and anatomic or functional asplenia; and updates guidance on vaccination of people with severe allergic reaction to eggs to state that vaccination in a medical setting supervised by a healthcare provider who is able to recognize and manage severe allergic reaction is needed only if administering a vaccine other than cell culture-based quadrivalent influenza vaccine (Flucelvax Quadrivalent; Seqirus) or recombinant hemagglutinin influenza vaccine (Flublok Quadrivalent; Sanofi Pasteur). 

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Q: Who is recommended to be vaccinated against influenza?

A: ACIP recommends annual vaccination for all people ages 6 months and older who do not have a contraindication to influenza vaccination.

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Q: Which influenza vaccines will be available during the 2020–21 influenza season?

A: Multiple manufacturers are producing influenza vaccine for the U.S. market for the 2020–21 season. Inactivated influenza vaccines will be produced using egg-based, cell culture-based, and recombinant technologies. Live attenuated nasal spray vaccine (Flumist Quadrivalent; AstraZeneca) will also be available. All but one influenza vaccine will be quadrivalent (containing four strains of influenza virus). The only trivalent vaccine available is the MF-59 adjuvanted vaccine (Fluad; Seqirus), however a quadrivalent MF-59 adjuvanted vaccine is also available (Fluad Quadrivalent; Seqirus). Both Fluad vaccines are indicated for adults age 65 years and older.
 
ACIP does not state a preference for one influenza vaccine over another for people for whom more than one vaccine is recommended for their age and health condition. A complete listing of influenza vaccine products is available at www.immunize.org/catg.d/p4072.pdf.

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Q: What are the changes to vaccine viruses for the 2020–21 influenza season?

A: Influenza vaccines produced for the current season will mostly be quadrivalent (four components). Quadrivalent vaccines contain two A viruses and two B viruses while trivalent vaccines contain two A viruses and one B virus.
 
For the 2020–21 season, U.S. egg-based influenza vaccines (i.e., vaccines other than Flucelvax Quadrivalent and Flublok Quadrivalent) will contain hemagglutinin (HA) derived from an influenza:

• A/Guangdong-Maonan/SWL1536/2019 (H1N1)pdm09-like virus,
• A/Hong Kong/2671/2019 (H3N2)-like virus,
• B/Washington/02/2019 (Victoria lineage)-like virus, and
• B/Phuket/3073/2013 (Yamagata lineage)-like virus (for quadrivalent vaccines).

U.S. cell culture-based (Flucelvax Quadrivalent) and recombinant (Flublok Quadrivalent) influenza vaccines will contain HA derived from an influenza:

• A/Hawaii/70/2019 (H1N1)pdm09-like virus,
• A/Hong Kong/45/2019 (H3N2)-like virus, 
• B/Washington/02/2019 (Victoria lineage)-like virus, and
• B/Phuket/3073/2013 (Yamagata lineage)-like virus.

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Q:  What are the new influenza vaccines available for the 2020–21 influenza season?

A: Fluzone High-Dose Quadrivalent (HD-IIV4, Sanofi Pasteur) and Fluad Quadrivalent (Seqirus), both for adults 65 years and older, are new for 2020–21. The HD-IIV4 replaces Fluzone High-Dose (trivalent). Both Fluad Quadrivalent and Fluad (trivalent) will be available this season.
 
HD-IIV4, Fluad (trivalent), and Fluad Quadrivalent are supplied as pre-filled syringes. A dose of HD-IIV4 is 0.7 mL; the dose of both Fluad and Fluad Quadrivalent vaccines is 0.5 mL.

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Q: Which formulations of influenza vaccines are licensed for various age groups?

A: Influenza vaccines differ with regard to age group indications. IAC has a handout that summarizes each of the products available for the current influenza vaccination season at www.immunize.org/catg.d/p4072.pdf. ACIP does not state a preference for one influenza vaccine over another for persons for whom more than one vaccine is recommended and is age- and health condition-appropriate.

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Q: Does ACIP prefer that healthcare professionals administer high-dose or adjuvanted influenza vaccine to people age 65 years and older, or is standard-dose influenza vaccine acceptable?

A: ACIP has no preference.

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Q: When does CDC recommend starting influenza vaccination?

A: CDC recommends that vaccination should be offered by the end of October. Vaccination should continue throughout the influenza season, including into the spring months (for example, through May), as long as influenza viruses are circulating and providers have unexpired vaccine.
 
Children age 6 months to 8 years without two prior doses of influenza vaccine need 2 doses. They should get their first influenza vaccination as soon as vaccine becomes available to ensure they are fully vaccinated before the influenza season begins; the minimum interval for the second dose is 28 days.
 
To avoid missed opportunities for vaccination, providers should offer vaccination during routine healthcare visits and hospitalizations. However, for people who need only 1 dose, early vaccination (i.e., July and August) can result in reduced immune protection towards the end of the influenza season, particularly for older adults.

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Q: Should our practice consider revaccinating our high risk and older patients a second time during the year due to concerns with waning immunity?

A: For people who have already been fully vaccinated, revaccination later in the season is not recommended.

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Q: Should Fluzone High-Dose Quadrivalent, Fluad (trivalent), or Fluad Quadrivalent be administered to patients younger than age 65 years?

A: No. These three vaccines are licensed only for people age 65 years and older and are not recommended for younger people.

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Q: Does ACIP recommend one influenza product over another for pregnant women?

A: Pregnant women can receive any inactivated or recombinant influenza vaccine. They should not be given FluMist Quadrivalent.

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Q: Which influenza vaccines can we give to children?

A: Four injectable inactivated influenza vaccines are now approved by FDA for children age 6 months and older:

• Fluzone Quadrivalent (Sanofi Pasteur),
• FluLaval Quadrivalent (GSK),
• Fluarix Quadrivalent (GSK), and
• Afluria Quadrivalent (Seqirus).

The inactivated cell culture-based influenza vaccine Flucelvax (Seqirus) is approved for people age 4 years and older.
 
The nasal spray live attenuated influenza vaccine FluMist Quadrivalent (AstraZeneca) is approved for healthy people age 2–49 years who are not pregnant. Information about all influenza vaccines available in the U.S., including product billing codes, is available in IAC's handout titled "Influenza Vaccine Products for the 2020–2021 Influenza Season" at www.immunize.org/catg.d/p4072.pdf. Information on vaccine products for the U.S. is also available on CDC's website at www.cdc.gov/flu/professionals/vaccines.htm.

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Q: Please provide details about the use of inactivated influenza vaccine in children younger than 3 years.

A: Afluria Quadrivalent (Seqirus) dosing is 0.25 mL given IM for children age 6–35 months and 0.5 mL for children age 3 years and older.
 
The dosing for FluLaval Quadrivalent (GSK) and Fluarix Quadrivalent (GSK) vaccines is 0.5 mL for children age 6 months and older.
 
For Fluzone Quadrivalent (Sanofi Pasteur), either 0.25 mL or 0.5 mL doses can be given to children age 6–35 months. For children age 3 years and older, the dose is 0.5 mL.
 
Flucelvax Quadrivalent (Seqirus) is recommended beginning at age 4 years at 0.5 mL dose, but should not be used for children younger than age 4 years.

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Q: Which children younger than age 9 years will need 2 doses of influenza vaccine in this influenza season?

A: Children age 6 months through 8 years should receive a second dose 4 weeks or more after the first dose 1) if they are receiving influenza vaccine for the first time, 2) if they did not receive a total of at least two doses of any seasonal influenza vaccine before July 1 of the current year, or 3) if their vaccination history is unknown. The two previous doses need not have been received during the same season or consecutive seasons.
 
IAC's handout titled "Guide for Determining the Number of Doses of Influenza Vaccine to Give to Children Ages 6 Months Through 8 Years" provides guidance on this issue; it is available at www.immunize.org/catg.d/p3093.pdf. 

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Q: Can a clinic vaccinate children younger than age 3 years with influenza vaccine taken from a multi-dose vial of influenza vaccine? The multi-dose vials contain thimerosal as a preservative.

A: Yes. Multi-dose vials of inactivated influenza vaccine contain a small amount of thimerosal to prevent bacterial and fungal growth in the vial. Thimerosal-containing vaccines are safe to use in children. No scientific evidence indicates that thimerosal in vaccines causes adverse events unless the patient has a severe allergy to thimerosal. However, a few states have enacted legislation that restricts the use of thimerosal-containing vaccines in children. To find out if your state has such restrictions, check with your state immunization program (see www.immunize.org/coordinators for contact information).

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Q: For whom is FluMist Quadrivalent approved?

A: FluMist Quadrivalent (AstraZeneca) is currently approved by FDA only for use among healthy non-pregnant persons age 2 through 49 years.

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Q: Is administering FluMist an aerosol-generating procedure requiring airborne precautions during the COVID-19 pandemic?

A: No. Giving FluMist is not considered an aerosol-generating procedure. See the CDC web page Vaccination Guidance During a Pandemic for additional details.

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Q: What types of personal protective equipment do healthcare personnel need for administering vaccines in light of COVID-19?

A: CDC recommends that healthcare personnel administering any vaccines during COVID-19 wear surgical masks and eye protection (goggles or face shields). N95 respirators are not recommended. Gloves are recommended when giving intranasal or oral vaccines because of the increased likelihood of coming into contact with a patient’s mucous membranes and body fluids. Gloves are optional for other vaccines. Importantly, hands should be washed and gloves, when worn, should be changed between each patient. See the CDC web page Vaccination Guidance During a Pandemic for additional details.

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Q: What are contraindications and precautions for inactivated influenza vaccines?

A: Contraindications to inactivated influenza vaccines are a severe allergic reaction to a prior dose of influenza vaccine or a severe allergy to an influenza vaccine component (except egg).
 
Precautions to inactivated influenza vaccine include moderate or severe acute illness, and history of Guillain-Barré syndrome within 6 weeks after a dose of influenza vaccine.

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Q: What are contraindications and precautions for the recombinant influenza vaccine (Flublok)?

A: Contraindications to Flublok include history of severe allergic reaction to any component of the vaccine. 
 
Precautions include moderate or severe acute illness, and history of Guillain-Barré syndrome within 6 weeks after a dose of influenza vaccine.

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Q: What are the contraindications and precautions for FluMist?

A: Contraindications are:

• a history of severe allergic reaction to a vaccine component (except egg––see next question) or after a previous dose of any influenza vaccine
• concomitant aspirin or salicylate-containing therapy in children and adolescents because of the risk of Reye syndrome
• children age 2 through 4 years who have received a diagnosis of asthma or whose parents or caregivers report that a healthcare provider has told them during the preceding 12 months that their child had wheezing or asthma or whose medical record indicates a wheezing episode during the preceding 12 months
• immunosuppression due to any cause including medications or HIV infection
• cerebral spinal fluid (CSF) leak, cochlear implant, or anatomic asplenia or functional asplenia (e.g., due to sickle cell anemia)
• close contacts and caregivers of severely immunosuppressed persons who require a protected environment (e.g., reverse isolation in a hospital)
• pregnancy
• receipt of influenza antiviral medication within the previous 48 hours for oseltamivir and zanamivir, previous 5 days for peramivir, and previous 17 days for baloxavir

Precautions are:

• moderate or severe acute illness with or without fever
• history of Guillain-Barré syndrome within 6 weeks after a dose of influenza vaccine
• asthma in a person age 5 years or older
• underlying medical conditions that might predispose to complications after influenza virus infection, such as chronic pulmonary, cardiovascular (except isolated hypertension), renal, hepatic, neurologic, hematologic, or metabolic disorders including diabetes mellitus

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Q: What is the latest ACIP guidance on influenza vaccination and egg allergy?

A: ACIP recommends that people with a history of egg allergy who have experienced only hives after exposure to egg should receive influenza vaccine without specific precautions (except a 15-minute observation period for syncope). Any age-appropriate vaccine may be used. For people who report having had an anaphylactic reaction to egg (more severe than hives), if a vaccine other than Flucelvax Quadrivalent (ccIIV, Seqirus) or Flublok Quadrivalent (RIV4, Sanofi Pasteur) is given, the vaccine should be administered in an inpatient or outpatient medical setting supervised by a healthcare provider who is able to recognize and manage severe allergic conditions. Although not specifically recommended by ACIP, providers may prefer administering an age-appropriate egg-free vaccine (ccIIV4 or RIV4) for patients with severe egg allergy.
 
A previous severe allergic reaction to influenza vaccine, regardless of the component suspected to be responsible for the reaction, is a contraindication to future receipt of the vaccine. For a complete list of vaccine components (i.e., excipients and culture media) used in the production of the vaccine, check the package insert (available at www.immunize.org/fda) or go to the vaccine excipient table in CDC’s Pink Book.

For more details about giving influenza vaccine to people with a history of egg allergy, see the ACIP guidance at www.cdc.gov/mmwr/volumes/69/rr/pdfs/rr6908a1-H.pdf. You also may find the IAC handout "Influenza Vaccination of People with a History of Egg Allergy" helpful (see www.immunize.org/catg.d/p3094.pdf).

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Q: We are considering co-locating our COVID-19 drive-through testing site and influenza vaccination sites. Can we vaccinate someone with suspected or confirmed COVID-19 infection?

A: CDC recommends deferring vaccination for people with suspected or confirmed COVID-19 until they have met criteria for no longer needing quarantine or isolation to avoid exposing healthcare personnel and other patients. When scheduling or confirming appointments for vaccination, patients should be screened for COVID-19 symptoms and recent exposure.

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Q: Is it acceptable to draw up vaccine into syringes at the beginning of the day? If it isn't, how much in advance can this be done?

A: CDC discourages the practice of prefilling vaccine into syringes for several reasons, including

• the increased possibility of administration and dosing errors,
• the increased risk of inappropriate storage temperature,
• the probability of bacterial contamination since the syringe will not contain a bacteriostatic agent, and
• the probability of reducing the vaccine's potency over time because of its interaction with the plastic syringe components. 

Prefilling vaccine into syringes also violates basic medication administration guidelines, which state that an individual should administer only those medications he or she has prepared and drawn up.
 
Although pre-drawing vaccine is discouraged, a limited amount of vaccine may be pre-drawn in a mass-immunization clinic setting under the following conditions:

• Only a single type of vaccine (for example, influenza) is administered at the mass-immunization clinic setting,
• vaccine is not drawn up in advance of its arrival at the mass-vaccination clinic site,
• these pre-drawn syringes are stored at temperatures appropriate for the vaccine they hold,
• no more than 1 vial or 10 doses (whichever is greater) is drawn into syringes, and
• clinic staff monitor patient flow carefully and avoid drawing up unnecessary doses or delaying administration of pre-drawn doses.

At the end of the clinic day, any remaining vaccine in syringes prefilled by staff should be discarded.

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