Recommendations for Prevention and Control of Influenza in Children, 2021-2022

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Recommendations for Prevention and Control of Influenza in Children, 2021-2022

                           Recommendations for Prevention and
                           Control of Influenza in Children,
                           COMMITTEE ON INFECTIOUS DISEASES

This technical report accompanies the recommendations of the                          abstract
American Academy of Pediatrics for the routine use of the influenza
vaccine and antiviral medications in the prevention and treatment of
influenza in children during the 2021–2022 season. Influenza
vaccination is an important intervention to protect vulnerable
populations and reduce the burden of respiratory illnesses during
circulation of severe acute respiratory syndrome coronavirus 2, which
is expected to continue during this influenza season. In this technical
report, we summarize recent influenza seasons, morbidity and
mortality in children, vaccine effectiveness, vaccination coverage, and
                                                                                      American Academy of Pediatrics, Itasca, Illinois
detailed guidance on storage, administration, and implementation. We
also provide background on inactivated and live attenuated influenza                  This document is copyrighted and is property of the American
                                                                                      Academy of Pediatrics and its Board of Directors. All authors have
vaccine recommendations, vaccination during pregnancy and                             filed conflict of interest statements with the American Academy of
breastfeeding, diagnostic testing, and antiviral medications for                      Pediatrics. Any conflicts have been resolved through a process
                                                                                      approved by the Board of Directors. The American Academy of
treatment and chemoprophylaxis.                                                       Pediatrics has neither solicited nor accepted any commercial
                                                                                      involvement in the development of the content of this publication.
                                                                                      Technical reports from the American Academy of Pediatrics benefit
                                                                                      from expertise and resources of liaisons and internal (AAP) and
                                                                                      external reviewers. However, technical reports from the American
INTRODUCTION                                                                          Academy of Pediatrics may not reflect the views of the liaisons or
This technical report accompanies the recommendations of the                          the organizations or government agencies that they represent.

American Academy of Pediatrics (AAP) for the routine use of influenza                 The guidance in this report does not indicate an exclusive course
                                                                                      of treatment or serve as a standard of medical care. Variations,
vaccine and antiviral medications in the prevention and treatment of                  taking into account individual circumstances, may be appropriate.
influenza in children during the 2021–2022 season.1                                   All technical reports from the American Academy of Pediatrics
                                                                                      automatically expire 5 years after publication unless reaffirmed,
                                                                                      revised, or retired at or before that time.
                                                                                      PEDIATRICS (ISSN Numbers: Print, 0031-4005; Online, 1098-4275).
2017–2018, 2018–2019, and 2019–2020 Influenza Seasons                                 Copyright © 2021 by the American Academy of Pediatrics

The 2017–2018 influenza season was the first season classified as a
high-severity season for all age groups, with high levels of outpatient
clinic and emergency department visits for influenzalike illness, high                  To cite: COMMITTEE ON INFECTIOUS DISEASES.
                                                                                        Recommendations for Prevention and Control of Influenza in
rates of influenza-related hospitalization, and high mortality.2–4                      Children, 2021–2022. Pediatrics. 2021;148(4):e2021053745
Influenza A (H3N2) predominated early, followed by a second wave of

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PEDIATRICS Volume 148, number 4, October 2021:e2021053745                                     FROM THE AMERICAN           ACADEMY OF PEDIATRICS
influenza B/Yamagata from March                                past decade, with elevated levels of                           A(H3N2) this season, despite
2018 onward. Although                                          influenzalike illness activity for a                           achieving the highest vaccination
hospitalization rates for children did                         total duration of 21 consecutive                               coverage reported in the last decade
not exceed those reported during                               weeks (compared with an average                                in children (62.6% overall) (Table 1,
the 2009 pandemic, they did surpass                            duration of 16 weeks).5 Variations                             Fig 1).5,6
rates reported in previous high-                               in circulating strains affected
severity A(H3N2)-predominant                                   vaccine efficacy. Influenza                                    The 2018–2019 season was of
seasons. Excluding the 2009                                    A(H1N1)pdm09 viruses                                           moderate severity, with similar
pandemic, the 188 pediatric deaths                             predominated from October to mid-                              hospitalization rates in children as
reported during the 2017–2018                                  February, and influenza A(H3N2)                                during the 2017–2018 season (71
season (approximately half of which                            viruses were identified more                                   per 100 000 among children 0–4
occurred in otherwise healthy                                  frequently from February to May.                               years old and 20.4 per 100 000
children) were the highest reported                            Influenza B (B/Victoria lineage                                among children 5–17 years old),
since influenza-associated pediatric                           predominant) represented                                       which were higher than those
mortality became a nationally                                  approximately 5% of circulating                                observed in previous seasons from
notifiable condition in 2004.2–4                               strains. Most characterized influenza                          2013–2014 to 2016–2017.5 Among
Among pediatric deaths of children                             A(H3N2) viruses were antigenically                             1132 children hospitalized with
6 months and older who were                                    distinct from the A(H3N2)                                      influenza and for whom data were
eligible for vaccination and for                               component of the 2018–2019                                     available, 55% had at least 1
whom vaccination status was                                    vaccine. The vaccine’s A(H3N2)                                 underlying medical condition; the
known, approximately 80% had not                               virus belonged to subclade 3C.2a1.                             most commonly reported underlying
received the influenza vaccine                                 Cocirculation of multiple genetically                          conditions were asthma or reactive
during the 2017–2018 season.2                                  diverse subclades of A(H3N2) was                               airway disease (26%), neurologic
Influenza vaccine effectiveness (VE)                           documented. Circulating viruses                                disorders (15.6%), and obesity
for the 2017–2018 season in                                    identified belonged to subclade                                (11.6%).7 A total of 144 influenza-
children is shown in Table 1.3                                 3C.2a1 or clade 3C.3a, with 3C.3a                              associated pediatric deaths were
                                                               viruses accounting for >70% of the                             reported.
The 2018–2019 influenza season                                 A(H3N2) viruses in the United
was the longest-lasting season                                 States. This likely contributed to an                          The 2019–2020 influenza season
reported in the United States in the                           overall lower VE against influenza                             was unusual and complicated by the

TABLE 1 Adjusted VE in Children in the United States, by Season, as Reported by the CDC, US Influenza VE Network
                                            2017–2018 H3N2 and B/Yamagata,                      2018–2019 H1N1 and H3N2,                      2019–2020 B/Victoria and H1N1,
    Influenza Type and Age Group                     VE% (95% CI)                                     VE% (95% CI)                                    VE% (95% CI)
    Influenza A and B
       Overall all ages                                38 (31 to 43)                                    29 (21 to 35)                                    39 (32 to 44)
       6 mo to 8 y                                     68 (55 to 77)                                    48 (37 to 58)                                    34 (19 to 46)
       9–17 y                                          32 (16 to 44)                                     7 (−20 to 28)                                   40 (22 to 53)
    Influenza A(H1N1)pdm09
       Overall all ages                                62 (50 to 71)                                    44 (37 to 51)                                   30 (21 to 39)
       6 mo to 8 y                                     87 (71 to 95)                                    59 (47 to 69)                                   23 (−3 to 42)
       9–17 y                                          70 (46 to 67)                                    24 (−18 to 51)                                  29 (−7 to 52)
    Influenza A(H3N2)
       Overall all ages                                22 (12 to 31)                                     9 (−4 to 20)                                          NA
       6 mo to 8 y                                     54 (33 to 69)                                    24 (1 to 42)                                           NA
       9–17 y                                          18 (−6 to 36)                                     3 (−30 to 28)                                         NA
    Influenza B/Victoria
       Overall all ages                                76 (45 to 89)                                     Not reported                                    45 (37 to 52)
       6 mo to 8 y                                     Not reported                                      Not reported                                    39 (20 to 54)
       9–17 y                                          Note reported                                     Not reported                                    43 (23 to 58)
    Influenza B/Yamagata
       Overall all ages                                48 (39 to 55)                                     Not reported                                          NA
       6 mo to 8 y                                     77 (49 to 90)                                     Not reported                                          NA
       9–17 y                                          28 (1 to 48)                                      Not reported                                          NA
VE is estimated as 100% × (1 − odds ratio [ratio of the odds of being vaccinated among outpatients with influenza-positive test results on the CDC’s real-time reverse transcripta-
se–polymerase chain reaction to the odds of being vaccinated among outpatients with influenza-negative test results]); odds ratios were estimated by using logistic regression.
Adjusted for study site, age group, sex, race and/or ethnicity, self-rated general health, number of days from illness onset to enrollment, and month of illness using logistic regres-
sion. NA, not applicable.

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2                                                                                                             FROM THE AMERICAN ACADEMY OF PEDIATRICS
FIGURE 1 Influenza vaccination coverage in children 6 months to 17 years of age in the United States, 2010–2020. Error bars represent 95% CIs around the
          estimates. Adapted from Centers for Disease Control and Prevention. Flu vaccination coverage, United States, 2019–20 influenza season. Available
          at: Accessed July 12, 2021; and National Immunization Survey-Flu

emergence of the severe acute                       2019–2020 vaccine. During this                        the highest hospitalization rates in
respiratory syndrome coronavirus 2                  season, the predominant A(H3N2)                       children, 68.2 per 100 000
(SARS-CoV-2) pandemic in early                      circulating clade was 3C.2a, subclade                 population overall, were reported
2020. Influenza activity began early                3C.2a1, with cocirculation of a small                 this season. The first peak of activity
in October 2019, continuing through                 proportion of 3C.3a, in contrast to                   occurred in early January, likely
mid-March 2020, with an abrupt                      the 2018–2019 season, when 3C.3a                      associated with influenza B
decline after the implementation of                 strains predominated. Estimates of                    circulation; the second peak
social distancing measures for                      the effectiveness of the 2019–2020                    occurred in February, when
mitigation of the SARS-CoV-2                        seasonal influenza vaccines against                   influenza A(H1N1)pdm09 became
pandemic. Although influenza                        medically attended influenza illness                  predominant; and the third peak in
B/Victoria viruses predominated                     from the US Flu VE Network are                        March was associated with
early in the season, influenza                      shown in Table 1.8 Susceptibility to                  cocirculation of influenza and SARS-
A(H1N1)pdm09 viruses were the                       available antiviral agents remained                   CoV-2. The CDC now has a separate
most predominant circulating strain.                greater than 99% for all circulating                  surveillance report for novel
Influenza A(H3N2) and the B/                        strains, but 0.5% of A(H1N1)pdm09                     coronavirus disease 2019
Yamagata lineage represented                        isolates tested by the Centers for                    (COVID-19)–like illness.10 The
approximately 4.1% and 0.8% of                      Disease Control and Prevention                        cumulative influenza hospitalization
circulating strains, respectively. A                (CDC) exhibited substantially                         rates per 100 000 population were
majority of characterized influenza                 reduced inhibition to oseltamivir                     92.3 among children 0 to 4 years
A(H1N1)pdm09 (82.5%) and                            and peramivir. Reduced                                old and 23.5 among children 5 to 17
influenza B/Victoria (59.7%) viruses                susceptibility to baloxavir has not                   years old. Hospitalization rates in
were antigenically similar to the                   been reported in the United States                    children 0 to 4 years old were
viruses included in the 2019–2020                   to date.9                                             higher than those seen for this age
influenza vaccine. Less than half                                                                         group during the 2009 influenza
(46.5%) of influenza A(H3N2)                        The 2019–2020 season was of                           pandemic, higher than the rate in
viruses were antigenically similar to               moderate severity, although 3 peaks                   adults 50 to 64 years old this season
the A(H3N2) component of the                        of influenzalike illness activity and                 (89.4 per 100 000), and the highest

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on record for this age group. Among        vaccination, and 7 had received 1               COVID-19 mortality observed this
children hospitalized with influenza       of 2 ACIP-recommended doses).                   season was attributable primarily to
and for whom data were available,                                                          COVID-19 and not influenza. No
48.6% had no recorded underlying           2020–2021 Influenza Season                      influenza-associated pediatric deaths
condition and 42.9% had at least 1         The 2020–2021 influenza season                  were identified from this past
underlying medical condition; the          was substantially and unusually                 season. One influenza-associated
most commonly reported underlying          mild, likely because of the                     pediatric death that occurred in
conditions were asthma or reactive         circulation of SARS-CoV-2 and the               January 2020 was reported during
airway disease (22.1%), neurologic         implementation of pandemic                      the 2020–2021 season.
disorders (17.5%), and obesity             mitigation measures. The circulation
(12%).                                     of influenza viruses was low,                   INFLUENZA MORBIDITY AND
                                           without a typical seasonal peak.                MORTALITY IN CHILDREN
There were 199 laboratory-                 From September 2020 to May 22,                  Influenza viruses are a common
confirmed influenza-associated             2021,
 People at High Risk of Influenza Complications
children 5 to 17 years of age and          be appropriate for a given patient,                    i. all vaccines: B/Phuket/
43% among children 6 months to 4           and vaccination should not be                             3073/2013-like virus (B/
years of age.18                            delayed to obtain a specific product.                     Yamagata/16/88 lineage)
Historically, up to 80% of influenza-      All 2021–2022 seasonal influenza                2. Trivalent vaccines do not include
associated pediatric deaths have           vaccines will be quadrivalent and                  the B/Yamagata component (not
occurred in unvaccinated children 6        contain the same influenza strains                 available in United States).
months and older. Influenza                as recommended by the World
vaccination is associated with             Health Organization (WHO) and                   Inactivated Influenza Vaccine
reduced risk of laboratory-                the US Food and Drug                            For the 2021–2022 season, all
confirmed influenza-related                Administration’s (FDA’s) Vaccines               licensed inactivated influenza
pediatric death.19 In one case-cohort      and Related Biological Products                 vaccines (IIVs) for children and
analysis comparing vaccination             Advisory Committee for the                      adults in the United States are
uptake in laboratory-confirmed             Northern Hemisphere.22 Both                     quadrivalent vaccines, with specific
influenza-associated pediatric deaths      influenza A(H1N1) and A(H3N2)                   age indications for available
to estimated vaccination coverage          components are different in this                formulations (Table 3). Among
among pediatric cohorts in the             season’s vaccine. The B                         vaccines available for children, 4 are
United States from 2010 to 2014,           components are unchanged. The                   egg based (seed strains grown in
Flannery et al19 found that only           influenza A strains may be                      eggs) and 1 is cell culture based
26% of children had received the           different for egg-based versus cell-            (seed strains grown in Madin-Darby
vaccine before illness onset,              or recombinant-based vaccines on                canine kidney cells). All inactivated
compared to an average vaccination         the basis of their optimal                      egg-based vaccines (Afluria
coverage of 48%. Overall VE against        characteristics for each platform,              Quadrivalent, Fluarix Quadrivalent,
influenza-associated death in              but all are matched to the strains              Flulaval Quadrivalent, and Fluzone
children was 65% (95% CI, 54% to           expected to circulate in the                    Quadrivalent) are licensed for
74%). More than half of children in        2021–2022 season.                               children 6 months and older and are
this study who died of influenza had                                                       available in single-dose, thimerosal-
$1 underlying medical condition            1. Quadrivalent vaccines contain the            free, prefilled syringes. The only
associated with increased risk of             following:                                   pediatric cell culture–based vaccine
severe influenza-related                      a. influenza A(H1N1) component:              (Flucelvax Quadrivalent) is now
complications; only 1 in 3 of these                i. egg-based vaccines: A/               licensed for children 2 years and
at-risk children had been                             Victoria/2570/2019                   older.23 The extension of the age
vaccinated; yet VE against death in                   (H1N1) pdm09-like virus              indication down from 4 years to 2
children with underlying conditions                   (new this season); and               years of age in March 2021 was
was 51% (95% CI, 31% to 67%).                      ii. cell- or recombinant-based          based on data from a randomized
Similarly, influenza vaccination                       vaccines: A/Wisconsin/              double-blind clinical efficacy study
reduces by three-quarters the risk of                  588/2019 (H1N1) pdm09-              conducted among children 2 to 18
severe life-threatening laboratory-                    like virus (new this                years of age over 3 seasons (2017 in
confirmed influenza in children                        season);                            the Southern Hemisphere and
requiring admission to the ICU.20             b. influenza A(H3N2) component:              2017–2018 and 2018–2019 in the
The influenza virus type might also                i. egg-based vaccines: A/               Northern Hemisphere), in which
affect the severity of disease. In a                  Cambodia/e0826360/2020               Flucelvax Quadrivalent
study of hospitalizations for                         (H3N2)-like virus (new this          demonstrated efficacy against
influenza A versus B, the odds of                     season); and                         laboratory-confirmed influenza
mortality were significantly greater               ii. cell- or recombinant-based          illness of 54.6% (95% CI, 45.7% to
with influenza B than with influenza                   vaccines: A/Cambodia/               62.1%), compared with a control
A and were not entirely explained                      e0826360/2020 (H3N2)-               vaccine (meningococcal serogroup
by underlying health conditions.21                     like virus (new this season);       ACWY conjugate vaccine).24
                                              c. B/Victoria component:
SEASONAL INFLUENZA VACCINES                        i. all vaccines: B/Washington/          A quadrivalent recombinant
The seasonal influenza vaccines                       02/2019-like virus (B/               baculovirus-expressed
licensed for children and adults for                  Victoria/2/87 lineage)               hemagglutinin influenza vaccine
the 2021–2022 season are shown in                     (unchanged); and                     (quadrivalent recombinant influenza
Table 3. More than one product may            d. B/Yamagata component:                     vaccine [RIV4]) (Flublok

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TABLE 3 Recommended Seasonal Influenza Vaccines for Different Age Groups: United States, 2021–2022 Influenza Season
                                                                                                                                                                                                                                        Presentation and Hemagglutinin Antigen                    Thimerosal Mercury
                                                                                                                                                                                                                                         Content (IIVs and RIV4) or Virus Count                         Content,
                                                                                                               Vaccine                                            Trade Name (Manufacturer)                     Age Group                  (LAIV4) per Dose for Each Antigen                       μg Hg/0.5-mL Dose                CPT Code
                                                                                                               Quadrivalent standard dose: egg-
                                                                                                                  based vaccines
                                                                                                                 IIV4                                          Afluria Quadrivalent (Seqirus)                    6–35 mo                0.25-mL prefilled syringe (7.5 μg/0.25 mL)                            0                         90685
                                                                                                                                                                              —                                 ≥36 mo                 0.5-mL prefilled syringe (15 μg/0.5 mL)                               0                         90686
                                                                                                                                                                              —                                 ≥6 mo                  5.0-mL multidose viala (15 μg/0.5 mL)                               24.5                       90687
                                                                                                                  IIV4                                         Fluarix Quadrivalent                             ≥6 mo                  0.5-mL prefilled syringe (15 μg/0.5 mL)                               0                         90686
                                                                                                                  IIV4                                         FluLaval Quadrivalent                            ≥6 mo                  0.5-mL prefilled syringe (15 μg/0.5 mL)                               0                         90686
                                                                                                                  IIV4                                         Fluzone Quadrivalent (Sanofi                      ≥6 mo                  0.5-mL prefilled syringe (15 μg/0.5 mL)                               0                         90686

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                                                                                                                                                                  Pasteur)                                                                (0.25 mL no longer available)

                                 October 2021
                                                                                                                                                                              —                                 ≥6 mo                  0.5-mL single-dose vial (15 μg/0.5 mL)                               0                         90686
                                                                                                                                                                              —                                 ≥6 mo                  5.0-mL multidose viala (15 μg/0.5 mL)                               25                         90687
                                                                                                               Quadrivalent standard dose: cell
                                                                                                                 culture–based vaccines
                                                                                                                 ccIIV4                                        Flucelvax Quadrivalent (Seqirus)                 ≥2 y                   0.5-mL prefilled syringe (15 μg/0.5 mL)                               0                         90674
                                                                                                                                                                              —                                 ≥2 y                   5.0 mL multidose viala (15 μg/0.5 mL)                               25                         90756
                                                                                                               Quadrivalent standard dose: egg-
                                                                                                                  based with adjuvant vaccines
                                                                                                                 aIIV4 MF-59 adjuvanted                        Fluad Quadrivalent (Seqirus)                     ≥65 y                  0.5-mL prefilled syringe (15 μg/0.5 mL)                               0                         90653
                                                                                                               Quadrivalent high dose: egg-
                                                                                                                  based vaccine
                                                                                                                 IIV4                                          Fluzone High-Dose Quadrivalent                   ≥65 y                  0.7-mL prefilled syringe (60 μg/0.7 mL)                               0                         90662
                                                                                                                                                                  (Sanofi Pasteur)
                                                                                                               Recombinant vaccine
                                                                                                                 RIV4                                          Flublok Quadrivalent (Sanofi                      ≥18 y                  0.5-mL prefilled syringe (45 μg/0.5 mL)                               0                         90682
                                                                                                               Live attenuated vaccine
                                                                                                                  LAIV4                                        FluMist Quadrivalent                             2–49 y                 0.2-mL prefilled intranasal sprayer (virus                            0                         90672
                                                                                                                                                                  (AstraZeneca)                                                           dose: 10 6.5–7.5 FFU/0.2 mL)
                                                                                                              Adapted from 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. 2021;70(5):1–28. The implementation guidance on supply, pricing, payment, CPT coding, and liability issues can be found at aIIV4, quadrivalent adjuvanted inactivated influenza
                                                                                                              vaccine; ccIIV4, quadrivalent cell culture–based inactivated influenza vaccine; CPT, Current Procedural Terminology; FFU, fluorescent focus unit; —, not applicable.

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                                                                                                                For vaccines that include a multidose vial presentation, a maximum of 10 doses can be drawn from a multidose vial.

Quadrivalent) is licensed only for          Only the 0.5-mL Fluzone prefilled               appetite, fatigue, muscle aches,
people 18 years and older. A high-          syringe will be available this season.          headache, arthralgia, and
dose quadrivalent inactivated               In addition, 2 other vaccines, Fluarix          gastrointestinal tract
influenza vaccine (IIV4) (Fluzone           Quadrivalent29 and FluLaval                     symptoms.
High-Dose Quadrivalent) containing          Quadrivalent,30 are licensed at a 0.5-
4 times the amount of antigen for           mL dose in children 6 to 35 months              IIVs can be administered
each virus strain compared with the         of age. These 2 vaccines do not have            concomitantly with other inactivated
standard-dose vaccines is licensed          a 0.25-mL dose formulation. Afluria             or live vaccines.32–36 The influenza
only for people 65 years and older.         Quadrivalent is the only pediatric              vaccine may be administered
The quadrivalent MF-59 adjuvanted           vaccine that has a 0.25-mL                      simultaneously or at any time before
inactivated vaccine (Fluad                  presentation for children 6 to 35               or after administration of the
Quadrivalent) was licensed for              months of age. Afluria 0.5 mL is                currently available COVID-19
people 65 years and older in                licensed for children 3 years and               vaccines.37 In general, although data
February 2020.23 Adjuvants may be           older only.31                                   are not available for concomitant
included in a vaccine to elicit a more                                                      administration of COVID-19 with
robust immune response, which               Given that different formulations of            other vaccines in children, extensive
                                            IIV for children 6 to 35 months of              experience with non-COVID-19
could lead to a reduction in the
                                            age are available, care should be               vaccines has demonstrated that
number of doses required for
                                            taken to administer the                         immunogenicity and adverse event
children. In one pediatric study, the
                                            appropriate volume and dose for                 profiles are generally similar when
relative vaccine efficacy of an MF-59
                                            each product. In each instance, the             vaccines are administered
adjuvanted influenza vaccine was
                                            recommended volume may be                       simultaneously as when they are
significantly greater than that of a
                                            administered from an appropriate                administered alone. Furthermore,
nonadjuvanted vaccine in the 6- to
                                            prefilled syringe, a single-dose vial,          concomitant administration with the
23-month age group.25 Adjuvanted
                                            or a multidose vial, as supplied by             influenza vaccine is being evaluated
seasonal influenza vaccines are not
                                            the manufacturer. For vaccines                  in adults (unpublished observations
licensed for children in the United
                                            that include a multidose vial                   presented at ACIP Influenza
                                            presentation, a maximum of 10                   Workgroup meeting), and data in
                                            doses can be drawn from a                       children are anticipated to inform
Children 36 months (3 years) and
                                            multidose vial. Importantly, dose               recommendations. Given that it is
older can receive any age-
                                            volume is different from the                    unknown whether reactogenicity of
appropriate licensed IIV,
                                            number of doses needed to                       COVID-19 vaccines will be increased
administered at a 0.5-mL dose
                                            complete vaccination. Children 6                with coadministration of the
containing 15 lg of hemagglutinin
                                            months to 8 years of age who                    influenza vaccine, the reactogenicity
(HA) from each strain. Children 6 to
                                            require 2 doses of the vaccine for              profile of the vaccines should be
35 months of age may receive any
                                            the 2021–2022 season should                     considered, and providers should
age-appropriate licensed IIV without
                                            receive 2 separate doses at the                 consult the most current ACIP and
preference for one product over
                                            recommended dose volume                         AAP guidance regarding
another. Several vaccines have been
                                            specified for each product.                     coadministration of COVID-19
licensed for children 6 to 35 months                                                        vaccines with influenza vaccines.38
of age since 2017 (Table 3). All are        IIVs are well tolerated in                      Overall, the benefits of timely
quadrivalent, but the dose volume,          children and can be used in                     vaccination with same-day
and therefore the antigen content,          healthy children as well as those               administration of IIV and other
may vary among different IIV                with underlying chronic medical                 recommended vaccines outweigh
products. In addition to a 0.25-mL          conditions. CDC best practice                   the risk of potential reactogenicity
(7.5 lg of HA per vaccine virus)            guidelines should be followed for               in children.
Fluzone Quadrivalent vaccine, a 0.5-        administration (https://www.cdc.
mL formulation of Fluzone                   gov/vaccines/hcp/acip-recs/                     Thimerosal-containing vaccines are
Quadrivalent containing 15 lg of HA         general-recs/). The most common                 not associated with an increased
per vaccine virus per dose was              injection site adverse reactions                risk of autism spectrum disorder in
licensed in January 2019 after these        after administration of IIV in chil-            children. Thimerosal from vaccines
2 formulations were shown to have           dren are injection site pain, red-              has not been linked to any
comparable safety and                       ness, and swelling. The most                    neurologic condition. The AAP
immunogenicity in a single                  common systemic adverse events                  supports the current WHO
randomized multicenter study.26–28          are drowsiness, irritability, loss of           recommendations for use of

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thimerosal as a preservative in                 children during the 2016–2017 and               reviewed available data on influenza
multiuse vials in the global vaccine            2017–2018 seasons, given concerns               epidemiology and VE for the
supply.39 Despite the lack of                   about its effectiveness against                 2018–2019 season and agreed that
evidence of harm, some states have              A(H1N1)pdm09. For the 2017–2018                 harmonizing recommendations
legislation restricting the use of              season, a new A(H1N1)pdm09-like                 between the AAP and CDC for the
vaccines that contain even trace                virus strain (A/Slovenia/2903/                  use of LAIVs in the 2019–2020
amounts of thimerosal. The benefits             2015) was included in the LAIV4,                season was appropriate. After the
of protecting children against the              replacing the previous A/Bolivia/               February 2020 ACIP meeting, the
known risks of influenza are clear.             559/2013 strain. A study conducted              AAP Committee on Infectious
Therefore, to the extent permitted              by the LAIV4 manufacturer                       Diseases reviewed available
by state law, children should receive           evaluated viral shedding and                    epidemiological and effectiveness
any available formulation of IIVs               immunogenicity associated with the              data for the previous and current
rather than delaying vaccination                LAIV4 formulation containing the                seasons to inform recommendations
while waiting for reduced                       new A(H1N1) pdm09-like virus                    for the 2020–2021 season. Despite
thimerosal-content or thimerosal-               among US children 24 to 48 months               the early circulation of
free vaccines. IIV formulations that            of age.41 Shedding and                          A(H1N1)pdm09 during the
are free of even trace amounts of               immunogenicity data suggested that              2018–2019 season and its
thimerosal are widely available                 the new influenza A(H1N1)pdm09-                 predominance during the
(Table 3).                                      like virus included in its latest               2019–2020 season, low use of the
                                                formulation had improved                        LAIV4 in the US population has
Live Attenuated (Intranasal)                    replicative fitness over previous               limited the evaluation of product-
Influenza Vaccine                               LAIV4 influenza A(H1N1)pdm09-like               specific VE, and no additional US
The intranasal live attenuated                  virus strains, resulting in an                  data on VE for the LAIV4 are
influenza vaccine (LAIV) was initially          improved immune response                        available. Although the proportion of
licensed in the United States in 2003           comparable to that of the LAIV3                 the LAIV used for vaccination is
for people 5 to 49 years of age as a            available before the 2009 pandemic.             unknown, interim overall VE (not
trivalent formulation (trivalent live           Shedding and replicative fitness are            specific to a type of vaccine) for the
attenuated influenza vaccine [LAIV3]),          not known to correlate with efficacy,           2019–2020 influenza season showed
and the approved age group was                  and no published effectiveness                  reassuring protection in children
extended to 2 years of age in 2007.             estimates for this revised                      against circulating influenza A and B
The quadrivalent formulation                    formulation of the vaccine against              strains (Table 1).42 Furthermore,
(quadrivalent live attenuated                   influenza A(H1N1)pdm09 viruses                  influenza vaccine coverage rates in
influenza vaccine [LAIV4]), licensed in         were available before the start of              children were stable until the
2012, was first available during the            the 2018–2019 influenza season                  COVID-19 pandemic.6 In European
2013–2014 influenza season,                     because influenza A(H3N2) and                   surveillance networks where
replacing the LAIV3.                            influenza B viruses predominated                uninterrupted use of the LAIV has
                                                during the 2017–2018 Northern                   continued from the 2016–2017 to
The CDC conducted a systematic                  Hemisphere season. Therefore, for               the 2019–2020 seasons, the United
review of published studies                     the 2018–2019 influenza season, the             Kingdom was the only country to
evaluating the effectiveness of the             AAP recommended the IIV4 or                     report final VE against medically
LAIV3 and LAIV4 in children from                trivalent inactivated influenza                 attended influenza for the
the 2010–2011 to the 2016–2017                  vaccine as the primary choice for               2018–2019 season. In children 2 to
influenza seasons, including data               influenza vaccination in children,              17 years of age, the reported VE
from US and European studies.40                 with LAIV4 use reserved for                     was 49.9% (95% CI, 14.3% to
The data suggested that the                     children who would not otherwise                78.0%) for A(H1N1)pdm09 and
effectiveness of the LAIV3 or LAIV4             receive an influenza vaccine and for            27.1% (95% CI, 130.5% to 77%)
for the influenza A(H1N1)pdm09                  whom LAIV use was appropriate for               for A(H3N2).43 The final adjusted VE
strain was lower than that of the IIV           age (2 years and older) and health              in the United States (where mostly
in children 2 to 17 years of age. The           status (ie, healthy, without any                the IIV was used) for 2018–2019
LAIV was similarly effective against            underlying chronic medical                      against A(H1N1)pdm09 was 59%
influenza B and A/H3N2 strains in               condition).                                     (95% CI, 47% to 69%) for children
some age groups compared with the                                                               6 months to 8 years of age but only
IIV. The LAIV was not recommended               In February 2019, the AAP                       24% (95% CI, 18% to 51%) for
by the CDC or AAP for use in                    Committee on Infectious Diseases                children 9 to 17 years of age. The

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reported US VE was 24% (95% CI,              vaccines is separated by a 4-week               determine if future receipt of the
1% to 42%) in children 6 months to           interval from LAIV4 vaccination.                vaccine is appropriate.
8 years of age and 3% (95%
CI, 30% to 28%) in children 9 to             LAIV and Immunocompromised                      Minor illnesses, with or without
17 years of age for A(H3N2).44               Hosts                                           fever, are not contraindications to
Direct comparisons cannot be made            The IIV is the vaccine of choice for            the use of influenza vaccines,
given differences in reporting of VE         anyone in close contact with a                  including among children with mild
for various age groups. Other                subset of severely                              upper respiratory infection
countries that use the LAIV (Canada,         immunocompromised people (ie,                   symptoms or allergic rhinitis. In
Finland) have not reported LAIV4-            those requiring a protected                     children with a moderate to severe
specific VE in the past several              environment). The IIV is preferred              febrile illness (eg, high fever, active
seasons. Small case numbers and              over the LAIV for contacts of                   infection, requiring hospitalization),
low LAIV use may also limit                  severely immunocompromised                      on the basis of the judgment of the
accurate VE calculations in these            people because of a theoretical risk            clinician, vaccination should be
countries. In general, as long as use        of infection attributable to LAIV               deferred until resolution of the
of the LAIV is low relative to the IIV,                                                      illness. Children with confirmed
                                             strains in an immunocompromised
it will be difficult to estimate LAIV                                                        COVID-19 can receive the influenza
                                             contact of an LAIV-immunized
VE accurately. Furthermore,                                                                  vaccine when the acute illness has
                                             person. Available data indicate a low
important variability in VE against                                                          resolved and/or illness is mild.
                                             risk of transmission of the virus
all strains is reported for both the                                                         Children with an amount of nasal
                                             from both children and adults
IIV and LAIV.                                                                                congestion that would notably
                                             vaccinated with the LAIV. Health
                                                                                             impede vaccine delivery into the
Influenza VE varies from season to           care personnel (HCP) immunized                  nasopharyngeal mucosa should have
season and is affected by many               with the LAIV may continue to work              the LAIV deferred until resolution or
factors, including age and health            in most units of a hospital, including          may receive the IIV.
status of the recipient, influenza           the NICU and general oncology
type and subtype, existing immunity          ward, using standard infection-                 A precaution for vaccination is a
from previous infection or                   control techniques. As a                        condition in a recipient that might
vaccination, and degree of antigenic         precautionary measure, people                   increase the risk or seriousness of a
match between vaccine and                    recently vaccinated with the LAIV               possible vaccine-related adverse
circulating virus strains. It is             should restrict contact with severely           reaction. A precaution also may exist
possible that VE also differs among          immunocompromised patients for 7                for conditions that might
individual vaccine products;                 days after immunization, although               compromise the ability of the host
however, product-specific                    there have been no reports of LAIV              to develop immunity after
comparative effectiveness data are           transmission from a vaccinated                  vaccination. Vaccination may be
lacking for most vaccines. Additional        person to an immunocompromised                  recommended in the presence of a
experience over multiple influenza           person. In the theoretical scenario in          precaution if the benefit of
seasons will help to determine               which symptomatic LAIV infection                protection from the vaccine
optimal use of the available vaccine         develops in an                                  outweighs the potential risks.
formulations in children. The AAP            immunocompromised host, LAIV
will continue to monitor annual                                                              A history of Guillain-Barre syndrome
                                             strains are susceptible to antiviral
influenza surveillance and VE                                                                (GBS) after influenza vaccination is
reports to update influenza vaccine                                                          considered a precaution for the
recommendations if necessary.                                                                administration of influenza vaccines.
                                             INFLUENZA VACCINE                               GBS is rare, especially in children,
                                             CONTRAINDICATIONS AND                           and there is a lack of evidence on
The most commonly reported
reactions of the LAIV4 in children                                                           risk of GBS after influenza
are runny nose or nasal congestion,          Anaphylactic and severe allergic                vaccination in children. Nonetheless,
headache, decreased activity or              reactions to any influenza vaccine              regardless of age, a history of GBS
lethargy, and sore throat. The LAIV4         are contraindications to vaccination.
outweigh the risks for certain                   close contacts and caregivers of              immunization. It is not necessary to
people who have a history of GBS                  those who are severely immuno-                inquire about an egg allergy before
(particularly if not associated with              compromised and require a pro-                the administration of any influenza
previous influenza vaccination) and               tected environment;                           vaccine, including on screening
who also are at high risk for severe             children and adolescents receiv-              forms. Routine prevaccination
complications from influenza.                     ing aspirin or salicylate-contain-            questions regarding anaphylaxis
                                                  ing medications;                              after receipt of any vaccine are
Specific precautions for the LAIV                children who have received other              appropriate. Standard vaccination
include a diagnosis of asthma in                  live-virus vaccines within the pre-           practice for all vaccines in children
children 5 years and older and the                vious 4 weeks (except for the rota-           should include the ability to respond
presence of certain chronic                       virus vaccine); however, the LAIV             to rare acute hypersensitivity
underlying medical conditions,                    can be administered on the same
                                                                                                reactions. Children who have had a
including metabolic disease,                      day with other live-virus vaccines
                                                                                                previous allergic reaction to the
diabetes mellitus, other chronic                  if necessary;
                                                                                                influenza vaccine should be
disorders of the pulmonary or                    children taking an influenza anti-
                                                                                                evaluated by an allergist to
cardiovascular systems, renal                     viral medication until 48 hours
                                                                                                determine if future receipt of the
dysfunction, or hemoglobinopathies.               (oseltamivir, zanamivir), 5 days
                                                                                                vaccine is appropriate.
Because the safety of the LAIV has                (peramivir), or 2 weeks (baloxa-
not been definitively established in              vir) after stopping the influenza
these situations, the IIV should be               antiviral therapy; if a child                 INFLUENZA VACCINES DURING
considered, and vaccination should                recently received the LAIV but                PREGNANCY AND BREASTFEEDING
not be delayed in these high-risk                 has an influenza illness for which            The influenza vaccine is
groups. People who should not                     antiviral agents are appropriate,             recommended by the ACIP, the
receive the LAIV are listed below.                the antiviral agents should be
                                                                                                American College of Obstetrics and
                                                  given; if antiviral agents are nec-
                                                                                                Gynecology, and the American
People in whom the LAIV is                        essary for treatment within 2
                                                                                                Academy of Family Physicians for all
contraindicated include the                       weeks of LAIV immunization,
                                                                                                women during any trimester of
following:                                        reimmunization or administra-
                                                                                                gestation for the protection of
                                                  tion of IIV is indicated because of
                                                                                                mothers against influenza and its
 children younger than 2 years;                  the potential effects of antiviral
                                                                                                complications.23,47 Substantial
 children 2 to 4 years of age with               medications on LAIV replication
                                                  and immunogenicity; and                       evidence has accumulated regarding
  a diagnosis of asthma or a his-
                                                 pregnant women.                               the efficacy of maternal influenza
  tory of recurrent wheezing or a
                                                                                                immunization in preventing
  medically attended wheezing epi-
                                                                                                laboratory-confirmed influenza
  sode in the previous 12 months                INFLUENZA VACCINES AND EGG
  because of the potential for                  ALLERGY                                         disease and its complications in
  increased wheezing after immu-                                                                both mothers and their infants in
                                                There is strong evidence that
  nization; in this age range, many                                                             the first 2 to 6 months of life.47–52
                                                individuals with egg allergies can
  children have a history of wheez-                                                             Pregnant women who are
                                                safely receive the influenza vaccine
  ing with respiratory tract ill-                                                               immunized against influenza at any
                                                without any additional precautions
  nesses and are eventually                                                                     time during their pregnancy provide
                                                beyond those recommended for any
  diagnosed with asthma;                        vaccine.45,46 The presence of an egg            protection to their infants during
 children with cochlear implants               allergy in an individual is not a               their first 6 months of life, when
  or active cerebrospinal fluid                 contraindication to receive the IIV             they are too young to receive the
  leaks;                                        or LAIV. Vaccine recipients with egg            influenza vaccine themselves,
 children who have a known or                  allergies are at no greater risk for a          through transplacental passage of
  suspected primary or acquired                 systemic allergic reaction than those           antibodies.49–57 Infants born to
  immunodeficiency or who are                   without egg allergies. Therefore,               women who receive influenza
  receiving immunosuppressive                   precautions, such as choice of a                vaccination during pregnancy have
  or immunomodulatory                           particular vaccine, special                     been shown to have a risk reduction
  therapies;                                    observation periods, or restriction of          of up to 72% (95% CI, 39% to 87%)
 children with anatomic or func-               administration to particular medical            for laboratory-confirmed influenza
  tional asplenia, including from               settings, are not warranted and                 hospitalization in the first few
  sickle cell disease;                          constitute an unnecessary barrier to            months of life.55

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It is safe to administer the IIV to        association between receipt of the              influenza.html and at https://www.
pregnant women during any                  IIV containing H1N1pdm09 and risk     
trimester of gestation and post            of spontaneous abortion when an                 infectioncontrol/peri-post-settings.
partum. Any licensed, recommended,         H1N1pdm09-containing vaccine had                htm. Breastfeeding should be
and age-appropriate influenza              also been received the previous                 encouraged even if the mother or
vaccine may be used, although              season.64 A follow-up study                     infant has influenza illness. The
experience with the use of the RIV4        conducted by the same investigators             mother should pump and feed
in pregnant women is limited. The          with a larger population and stricter           expressed milk if she or her infant is
LAIV is contraindicated during             outcome measures did not show this              too sick to breastfeed. If the breast-
pregnancy. Data on the safety of           association and further supported               feeding mother requires antiviral
influenza vaccination at any time          the safety of the influenza vaccine             agents, treatment with oral oselta-
during pregnancy continues to              during pregnancy.65                             mivir is preferred. The CDC does not
support the safety of influenza                                                            recommend use of baloxavir for
immunization during                        Women in the postpartum period                  treatment of pregnant women or
pregnancy.47,49–54,58 In a 5-year          who did not receive influenza                   breastfeeding mothers. There are no
retrospective cohort study from            vaccination during pregnancy should             available efficacy or safety data in
2003 to 2008 with more than                be encouraged to discuss receiving              pregnant women, and there are no
10 000 women, influenza                    the influenza vaccine before                    available data on the presence of
vaccination in the first trimester         discharge from the hospital with                baloxavir in human milk, the effects
                                           their obstetrician, family physician,           on the breastfed infant, or the
was not associated with an increase
                                           nurse midwife, or other trusted                 effects on milk production.
in the rates of major congenital
                                           provider. Women who traditionally
malformations.59 Similarly, a
                                           experience barriers to preventive
systematic review and meta-analysis                                                        VACCINE STORAGE AND
                                           care (eg, women who do not qualify
of studies of congenital anomalies                                                         ADMINISTRATION
                                           for Medicaid) should be offered
after vaccination during pregnancy,                                                        The AAP storage and handling tip
                                           vaccination before hospital
including data from 15 studies (14                                                         sheet provides resources for
                                           discharge or offered information in
cohort studies and 1 case-control                                                          practices to develop comprehensive
                                           their preferred language about free
study), did not show any association                                                       vaccine management protocols to
                                           vaccine clinics. Vaccination during
between congenital defects and                                                             keep the temperature for vaccine
                                           breastfeeding is safe for mothers
influenza vaccination in any                                                               storage constant during a power
                                           and their infants.
trimester, including the first                                                             failure or other disaster.67 The AAP
trimester of gestation.60                  Breastfeeding is strongly                       recommends the development of a
Assessments of any association with        recommended to protect infants                  written disaster plan for all practice
influenza vaccination and preterm          against influenza viruses by                    settings. Additional information is
birth and infants small for                activating innate antiviral                     available at
gestational age have yielded               mechanisms, specifically type 1                 During the COVID-19 pandemic, the
inconsistent results, with most            interferons. Human milk from                    AAP recommends that influenza vac-
studies reporting a protective effect      mothers vaccinated during the third             cine administration follow CDC guid-
or no association against these            trimester also contains higher levels           ance for administration of
outcomes.61,62 The authors of a            of influenza-specific immunoglobulin            immunizations (https://www.cdc.
cohort study from the Vaccines and         A.66 Greater exclusivity of                     gov/vaccines/pandemic-guidance/
Medications in Pregnancy                   breastfeeding in the first 6 months             index.html). Vaccination in the medi-
Surveillance System of vaccine             of life decreases the episodes of               cal home is ideal to ensure that
exposure during the 2010–2011 to           respiratory illness with fever in               pediatric patients receive other vac-
2013–2014 influenza seasons found          infants of vaccinated mothers. For              cinations and routine care in a
no significant association of              infants born to mothers with                    timely manner and receive catch-up
spontaneous abortion with influenza        confirmed influenza illness at                  immunizations if delays have
vaccine exposure in the first              delivery, breastfeeding is                      occurred because of the pandemic.
trimester or within the first 20           encouraged, and guidance on                     In general, infection-prevention
weeks’ gestation.63 One                    breastfeeding practices can be found            measures should be in place for all
observational Vaccine Safety               at                         patient encounters, including screen-
Datalink study conducted during the        breastfeeding/breastfeeding-                    ing for symptoms, physical distanc-
2010–2011 and 2011–2012                    special-circumstances/                          ing, respiratory and hand hygiene,
influenza seasons indicated an             maternal-or-infant-illnesses/                   and surface decontamination. In

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12                                                                                             FROM THE AMERICAN ACADEMY OF PEDIATRICS
addition to standard precautions                LAIV                                            onset of the influenza season.
and hand hygiene, during the                    The cold-adapted, temperature-                  Children who require only 1 dose of
COVID-19 pandemic, it is recom-                 sensitive LAIV4 formulation is                  the influenza vaccine should also
mended that vaccine administrators              shipped and stored at 2 C to 8 C              ideally be vaccinated by the end of
wear a surgical face mask (not N95              (35 F–46 F) and administered                  October. Recent data in adults
or respirator) at all times and eye             intranasally in a prefilled single-use          suggest that early vaccination (July
protection if the level of community            sprayer containing 0.2 mL of the                or August) might be associated with
spread is moderate or elevated.68               vaccine. A removable dose-divider               suboptimal immunity before the end
Administration of the LAIV intrana-             clip is attached to the sprayer to              of the influenza season, and the CDC
sally is not an aerosol-generating              facilitate administration of 0.1 mL             now discourages vaccination in the
procedure; however, vaccine admin-              separately into each nostril. If the            summer months, particularly among
istrators are advised to wear gloves            child sneezes immediately after                 older adults.37
when administering the LAIV given               administration, the dose should not
                                                be repeated.                                    Although the evidence is limited in
the potential for contact with respi-
                                                                                                children, recent reports raise the
ratory secretions. Gloves used for
                                                                                                possibility that early vaccination
intranasal or intramuscular vaccine             TIMING OF VACCINATION AND
                                                DURATION OF PROTECTION                          might contribute to reduced
administration should be changed
                                                                                                protection later in the influenza
with every patient. Gowns are not               Although peak influenza activity in
                                                                                                season.69–80 In these studies, VE
required.                                       the United States tends to occur
                                                                                                decreased within a single influenza
                                                from January to March, influenza
                                                                                                season, and this decrease was
                                                can circulate from early fall
                                                                                                correlated with increasing time after
                                                (October) to late spring (May), with
IIVs                                                                                            vaccination. However, this decay in
                                                one or more disease peaks. This
IIVs for intramuscular injection are                                                            VE was not consistent across
                                                pattern of circulation was
shipped and stored at 2 C to 8 C                                                              different age groups and varied by
                                                substantially altered during the
(36 F–46 F); vaccines that are                                                                season and virus subtypes. In some
                                                COVID-19 pandemic. Predicting the
                                                                                                studies, waning VE was more
inadvertently frozen should not be              onset and duration or the severity of
                                                                                                evident among older adults and
used. These vaccines are                        the influenza season with accuracy
                                                                                                younger children72,74 and with
administered intramuscularly into               is impossible. It is also challenging
                                                                                                influenza A(H3N2) viruses more
the anterolateral thigh of infants and          to balance public health strategies
                                                                                                than influenza A(H1N1) or B
young children and into the deltoid             needed to achieve high vaccination
                                                                                                viruses.73,76,78 A multiseason
muscle of older children and adults.            coverage with achieving optimal
                                                                                                analysis from the US Flu VE
Given that various IIVs are available,          individual immunity for protection
                                                against influenza at the peak of                Network found that VE declined by
careful attention should be paid to
                                                seasonal activity, knowing that the             approximately 7% per month for
ensure that each product is used
                                                duration of immunity after                      influenza A (H3N2) and influenza B
according to its approved age
                                                vaccination can wane over time.                 and by 6% to 11% per month for
indication, dosing, and volume of                                                               influenza A (H1N1)pdm09 in
administration (Table 3). A 0.5-mL              Initiation of influenza vaccination
                                                before influenza is circulating in the          individuals 9 years and older.71 VE
unit dose of any IIV should not be                                                              remained greater than 0 for at least
                                                community and continuing to
split into 2 separate 0.25-mL doses.                                                            5 to 6 months after vaccination. A
                                                vaccinate throughout the influenza
If a lower dose than recommended                                                                more recent study of children older
                                                season are important components of
is inadvertently administered to a                                                              than 2 years also found evidence of
                                                an effective influenza vaccination
child 36 months or older (eg, 0.25                                                              declining VE, with an odds ratio
mL), an additional 0.25-mL dose                                                                 increasing approximately 16% with
should be administered to provide a             Complete influenza vaccination by               each additional 28 days from
full dose of 0.5 mL as soon as                  the end of October is recommended               vaccine administration.77 Another
possible. The total number of full              by the CDC and AAP. Children who                study evaluating VE from the
doses appropriate for age should be             need 2 doses of the vaccine should              2011–2012 to the 2013–2014
administered. If a child is                     receive their first dose as soon as             influenza seasons demonstrated
inadvertently vaccinated with a                 possible when the vaccine becomes               54% to 67% protection from 0 to
formulation only approved for                   available, to allow sufficient time for         180 days after vaccination.75 Finally,
adults, the dose should be counted              receipt of the second dose $4                   a multiseason study in Europe from
as valid.                                       weeks after the first, before the               2011–2012 to 2014–2015 showed a

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                                           from by guest on September 16, 2021                         13
steady decline in VE down to 0%             coding, and liability issues; these             practice-specific Web sites, or social
protection by 111 days after                documents can be found at https://              media platforms); creating walk-in
vaccination.76                                        influenza vaccination clinics;
                                            pages-in-progress/influenza/                    extending hours beyond routine
Further evaluation is needed before         managing-influenzavaccination-                  times during peak vaccination
any policy change in timing of              in-your-practice/. The committee                periods; administering the influenza
influenza administration in children        supports adequate payment from                  vaccine during both well-child
is made. An early onset of the              public and private payers for the               examinations and sick visits as well
influenza season is a concern when          vaccine product and administration              as in hospitalized patients, especially
considering delaying vaccination.           in the pediatric population. Informa-           those at high risk of influenza
Until there are definitive data             tion on preparing your practice to              complications, before hospital
demonstrating waning immunity               administerinfluenza vaccines during             discharge (unless medically
influences VE in children,                  the COVID-19 pandemic can be                    contraindicated); implementing
administration of the influenza             found at              standing orders for influenza
vaccine should not be delayed to a          en/pages/2019-novel-                            vaccination; considering how to
later date because this increases the       coronaviruscovid-19-infections/                 immunize parents, adult caregivers,
likelihood of missing influenza             help-for-pediatricians/                         and siblings (see risk management
vaccination altogether.81 Providers         preparing-for-flu-season/. HCP,                 guidance associated with adult
may continue to offer vaccination as        influenza campaign organizers, and              immunizations in ref 85) at the
long as influenza is circulating and        public health agencies are encour-              same time as children; and working
until June 30 of each year, when the        aged to collaborate to develop                  with other institutions (eg, schools,
seasonal influenza vaccine expires,         improved strategies for planning,               child care programs, local public
because the duration of influenza           distribution, communication, and                health departments, and religious
circulation is unpredictable.               administration of vaccines. For                 organizations) or alternative care
Furthermore, a person may                   example, pediatricians can play a               sites, such as pharmacies and
experience more than 1 influenza            key role in educating and assisting             hospital emergency departments, to
infection during a given season             early childhood education centers               expand venues for administering the
because of the various cocirculating        and schools in educating parents on             vaccine. If a child receives the
strains. Although influenza activity        the importance of influenza immuni-             influenza vaccine outside his or her
in the United States is typically low       zation. Resources for effective com-            medical home, such as at a
during the summer, influenza cases          munication and messaging                        pharmacy, retail-based clinic, or
and outbreaks can occur,                    strategies, including promoting vac-            another practice setting, appropriate
particularly among international            cinations and providing resources               documentation of vaccination should
travelers, who may be exposed to            for pediatricians to communicate                be provided to the patient to be
influenza year-round, depending on
                                            with patients, families, and the com-           shared with his or her medical
the destination.
                                            munities they serve, are available on           home and entered into the state or
                                            the AAP Web site (https://services.             regional immunization information
VACCINE IMPLEMENTATION                                       system (ie, registry).
The AAP Partnership for Policy              campaigns-and-toolkits/
Implementation has developed a              immunizations and https://www.                  Concerted efforts among the
series of definitions using accepted                     aforementioned groups, plus vaccine
health information technology               policy/aap-health-initiatives/                  manufacturers, distributors, and
standards to assist in the                  immunizations/Influenza-                        payers, are necessary to prioritize
implementation of vaccine                   Implementation-Guidance/Pages/                  distribution appropriately to the
recommendations in computer                 Patient-Family-and-Community.                   primary care office setting and
systems and quality measurement             aspx).                                          patient-centered medical home
efforts. This document is available at                                                      before other venues, especially                   Pediatricians and other pediatric               when vaccine supplies are delayed
professional-resources/                     health care providers should plan to            or limited. Payers should eliminate
quality-improvement/                        make the influenza vaccine easily               remaining patient responsibility cost
Pages/Partnership-for-Policy-               accessible for all children. Examples           barriers to the influenza vaccine
Implementation.aspx. In addition,           include sending alerts to families              where they still exist. Similar efforts
the AAP has developed implementa-           that vaccine is available (eg, e-mails,         should be made to eliminate the
tion guidance on supply, payment,           texts, letters, patient portals,                vaccine supply discrepancy between

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14                                                                                              FROM THE AMERICAN ACADEMY OF PEDIATRICS
privately insured patients and those            patients and colleagues by receiving            available and prioritized to
eligible for vaccination through the            influenza vaccination annually.                 document influenza vaccination.
Vaccines for Children program.                                                                  Two-dimensional barcodes have
American Indian and Alaskan native              INFLUENZA VACCINE COVERAGE                      been used to facilitate more efficient
children, who are eligible for                                                                  and accurate documentation of
                                                Although national influenza
vaccines through the Vaccines for                                                               vaccine administration, with limited
                                                vaccination coverage among
Children program, are at higher risk                                                            experience to date. Additional
                                                children had remained stable and
for influenza complications and                                                                 information concerning current
                                                even increased in the past several
should be prioritized in a vaccine                                                              vaccines shipped with two-
                                                seasons before the COVID-19
shortage (Table 2).                                                                             dimensional barcodes can be found
                                                pandemic, overall vaccination
Population health can benefit from              coverage remains suboptimal (Fig
pediatricians’ discussions about                1). The Healthy People 2020
vaccine safety and effectiveness.               national target of 70% of children              Children’s likelihood of being
Pediatricians and their office staff            and adults vaccinated against                   immunized according to
can influence vaccine acceptance by             influenza was not achieved, with                recommendations appears to be
explaining the importance of annual             coverage lagging by 6 percentage                associated with the immunization
influenza vaccination for children              points for children and almost 20               practices of their parents. The
and emphasizing when a second dose              percentage points for adults. The               authors of one study found that
of the vaccine is indicated. The AAP            newly launched Healthy People                   children were 2.77 times (95% CI,
and CDC have created communication              2030 has, therefore, set a target for           2.74 to 2.79) more likely to be
resources to convey these important             influenza vaccination of people $6              immunized against seasonal
messages and to help the public                 months of age at 70%.87 Additional              influenza if their parents were
understand influenza                            options for vaccination of children             immunized.48 When parents who
recommendations. Resources will be              may provide a means to improve                  were previously not immunized had
available on Red Book Online (https://          coverage, particularly in pharmacies            received immunization for seasonal            and child care and school-based                 influenza, their children were 5.44
ssPage.aspx?SelfServeContentId=                 settings. Achieving high coverage               times (95% CI, 5.35 to 5.53) more
influenza-resources).                           rates of the influenza vaccine in               likely to receive the influenza
                                                infants and children is a priority to           vaccine.
The AAP supports mandatory                      protect them against influenza
influenza vaccination programs for all          disease and its complications.                  Pediatric offices may choose to
HCP in all settings, including                                                                  serve as a venue for providing
outpatient settings. Optimal prevention         The AAP and CDC recommend                       influenza vaccination for parents
of influenza in the health care setting         vaccine administration at any visit             and other care providers of children,
depends on the vaccination of at least          to the medical home during                      if the practice is acceptable to both
90% of HCP. Vaccine coverage among              influenza season when it is not                 pediatricians and the adults who are
HCP was 81.1% during the                        contraindicated, at specially                   to be vaccinated, particularly when
2018–2019 season, up from 78.4% the             arranged vaccine-only sessions, and             it can help reduce inequities in
previous year.86 Influenza vaccination          through cooperation with public                 vaccination access. Medical liability
programs for HCP benefit the health of          health departments, community                   and payment issues, along with
employees, their patients, and                  sites, schools, and Head Start and              medical record documentation
members of the community, especially            child care facilities to provide the            requirements, need to be considered
because HCP frequently come into                influenza vaccine. It is important              before a pediatrician begins
contact with patients at high risk of           that annual delivery of the influenza           immunizing adults (see risk
influenza illness in their clinical             vaccine to primary care medical                 management guidance associated
settings. Mandatory influenza                   homes be timely to avoid missed                 with adult immunizations in ref 85).
immunization for all HCP is considered          opportunities. If alternate venues,             Pediatric practices should be aware
to be ethical, just, and necessary to           including pharmacies and other                  of payment implications, including
improve patient safety. For the                 retail-based clinics, are used for              nonpayment or having the parent
prevention and control of influenza,            vaccination, a system of patient                inappropriately attributed by a
HCP must prioritize the health and              record transfer is crucial to maintain          payer as a patient of the
safety of their patients, honor the             the accuracy of immunization                    pediatrician’s office. The AAP
requirement of causing no harm, and             records. Immunization information               supports efforts to overcome these
act as role models for both their               systems should be used whenever                 payment barriers with insurance

PEDIATRICS Volume 148, number 4,Downloaded
                                 October 2021
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