Next Article in Journal
How European Research Projects Can Support Vaccination Strategies: The Case of the ORCHESTRA Project for SARS-CoV-2
Previous Article in Journal
Changes in the Epidemiology of Rubella: The Influence of Vaccine-Introducing Methods and COVID-19
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Vaccines
Volume 11
Issue 8
10.3390/vaccines11081360
vaccines-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Systematic Review

Parental Acceptance, Parental Hesitancy, and Uptake of Seasonal Influenza Vaccination among Children Aged 6–59 Months: A Systematic Review and Meta-Analysis

by
Paul Shing-fong Chan
1,
Yuan Fang
2,
Joseph Kawuki
1,
Siyu Chen
1,
Xue Liang
1,
Phoenix Kit-han Mo
1 and
Zixin Wang
1,*
1
Centre for Health Behaviours Research, Jockey Club School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China
2
Department of Health and Physical Education, The Education University of Hong Kong, Hong Kong, China
*
Author to whom correspondence should be addressed.
Vaccines 2023, 11(8), 1360; https://doi.org/10.3390/vaccines11081360
Submission received: 8 July 2023 / Revised: 2 August 2023 / Accepted: 9 August 2023 / Published: 13 August 2023
Browse Figures
Versions Notes

Abstract

:
This systematic review and meta-analysis summarises the literature on parental acceptance, parental hesitancy, uptake, and the associated factors of seasonal influenza vaccination (SIV) among children aged 6–59 months. Studies were sourced from the following platforms: PubMed, Web of Science, MEDLINE, and EMBASE databases. A random-effects model was used to evaluate the prevalence and 95% confidence intervals (CI) of parental acceptance, parental hesitancy, and SIV uptake in the last flu season and lifetime among children. A total of 36 studies were included for analysis. The overall prevalence was 64% for parental acceptance (95% CI: 51–75%), 34% for parental hesitancy (95% CI: 22–48%), 41% for SIV uptake in the last flu season (95% CI: 33–50%), and 46% for SIV uptake in a lifetime (95% CI: 20–74%). Associated factors of parental acceptance/hesitancy and uptake included the age of the children or parents, parental education level, household income level, ethnicity, and other modifiable factors, including perceived benefits, perceived barriers, perceived severity, perceived susceptibility, and cues to action related to SIV. Meta-regression analyses revealed regional differences in parental acceptance (Americas: 79% vs. Asia: 60%). The results provided implications informing us of the development of intervention programs targeting parents to improve SIV coverage among young children.

1. Introduction

Seasonal influenza is a common respiratory tract infection and a public health problem, particularly in children [1]. It is a significant cause of illness in young children aged under five years, who are at a greater risk of complications, which results in an estimated 870,000 hospitalisations and 10,200 deaths across the globe every year [2,3,4,5]. Children aged 6–59 months are more susceptible to seasonal influenza and have more severe consequences than the older groups [6,7]. For instance, children aged 6–59 months had higher rates than those aged 5–59 years in infection (83.7 vs. 10.2–16.4 per 100,000 individuals), hospitalisation (6.7–10.9 vs. 1.7–3.2 per 10,000 individuals), and mortality of seasonal influenza (0.2 vs. 0.02–0.04 per 100,000 individuals) [6,7]. Therefore, effective measures, such as vaccination, to prevent younger children from seasonal influenza infection are of vital importance [6,7].
Seasonal influenza vaccination (SIV) is considered one of the most effective ways to prevent influenza illness and severe complications from influenza virus infection [4,8,9]. It was shown that vaccinated young children had fewer respiratory illnesses and primary care consultations than their unvaccinated counterparts, and SIV could help reduce hospitalisation by 70% [10,11]. It was reported that not only did SIV protect the children, but it also protected the whole community and helped reduce influenza incidence in the general population [12]. Due to the constant mutation of the influenza virus, the World Health Organization (WHO) recommends children aged 6–59 months receive SIV every year [13]. Many countries implemented this guideline for SIV among children aged 6–59 months [14,15,16].
Despite the WHO’s recommendations, the successful implementation of SIV for children faced various obstacles, resulting in a low immunisation rate. Since parents are the main healthcare decision-makers for their young children, parents’ attitudes and perceptions of SIV play an important role in children’s SIV uptake. Across countries, studies reported a higher level of parental hesitancy for SIV among parents of children under the age of five years than parents of children aged 5–18 years (43–85% vs. 19.5–25.8%) [17,18,19]. As a result, the SIV uptake among children aged 6–59 months in the last flu season in these countries (9–45%) was lower than their older counterparts (59%) as well as the target SIV coverage rate (75%) recommended by the WHO [13,20,21,22]. It is possible that the factors that influence parental decisions regarding the vaccination of young children may be different from those that influence the vaccination of older children. Parents of children aged under five years expressed concerns that it was too young for their children to receive SIV, and they worried that SIV would have a negative effect on interactions with other vaccines to be received by their children [23,24,25]. These parents also worried that their young children may catch influenza from the vaccine [26,27]. Furthermore, they believed that natural immunity to influenza was better for their young children [28]. All these are unique obstacles for parents to vaccinate their children aged under five years. A systematic review was conducted in 2017 to investigate factors affecting routine childhood vaccination, including SIV, among children aged under 5 years [29]. However, the aforementioned systematic review did not cover countries in which SIV was not part of routine childhood vaccination [30]. In many countries (e.g., China, Singapore, and Poland), routine childhood vaccination programs for children aged under 5 years did not include SIV. From the existing literature, it is observed that there is no systematic review specifically looking at SIV uptake among children aged under five years. Therefore, a thorough understanding of the level of parental acceptance, parental hesitancy, and SIV uptake among children aged under five years, as well as their associated factors, is important for intervention development and policymaking in order to increase SIV coverage in this group of children.
This systematic review and meta-analysis was, therefore, conducted to synthesise and summarise the available literature on the levels of parental acceptance, parental hesitancy, and SIV uptake in the last flu season and lifetime in children aged 6–59 months as well as factors associated with parental acceptance/hesitancy and children’s SIV uptake.

2. Materials and Methods

2.1. Study Design

This systematic review and meta-analysis was registered in PROSPERO (CRD42023428862) and conducted according to the PRISMA guideline [30]. We included studies reporting on parental acceptance, parental hesitancy, and uptake rates of SIV in the last flu season and lifetime among children aged 6–59 months. Studies were sourced from the following platforms: PubMed, Web of Science, MEDLINE, and EMBASE databases.

2.2. Search Strategy

A comprehensive search was conducted using a number of appropriate keywords in order to identify studies reporting on parental acceptance, parental hesitancy, uptake, and the associated factors of parental acceptance/hesitancy and children’s SIV uptake in children aged 6–59 months. To match the aim of this systematic review, there were five sets of keywords for searching articles, which were related to the following: (1) acceptance/hesitancy/uptake/determinants; (2) parent; (3) influenza; (4) vaccination; and (5) children. The research team discussed to achieve a consensus on the terms to be included in each set. The asterisk “*” was appended to each term to search for variations of those terms. Additionally, the Boolean operators “OR” was used to link each term in each set and “AND” was used to link each set of the terms. The complete search strategy is described as follows:
(1)
willing* OR accept* OR refus* OR hesitan* OR inten* OR reject* OR declin* OR uptake* OR factor* OR determinant* OR reason* OR facilitator* OR barrier* OR attitude* OR perception* OR view* OR predict* OR enabl* OR knowledge OR perspective*;
(2)
parent* OR guardian* OR caregiver*;
(3)
influenza OR flu;
(4)
vaccin* OR immuni*;
(5)
child* OR infant* OR toddler* OR pediatr* OR preschool* OR kindergart*;
(6)
1 AND 2 AND 3 AND 4 AND 5.

2.3. Inclusion and Exclusion Criteria

Peer-reviewed original studies published in English-language journals using quantitative, qualitative, or mixed-method methodology were included in this systematic review. The eligible studies should report parental acceptance, parental hesitancy, uptake, and the associated factors of SIV in children aged 6–59 months. The articles were searched with no restriction on country or region. An article was excluded if it was (1) the development of a study protocol/scale/measurement tool; (2) unclear about whether the participants were parents/caregivers of children; (3) the modelling or projection for prediction of SIV uptake among children; or (4) other grey papers, such as government documents/reports, newspapers, textbooks, book chapters, and preprints. As government documents/reports and newspapers were not written for scientific purposes, they were excluded from consideration. In view of the fact that grey papers were generally published without peer review, there are concerns regarding the quality and reliability of these publications.

2.4. Data Extraction

Two independent reviewers (P.S.-f.C. and J.K.) carried out data extraction and reference searching parallelly. Five papers were randomly selected for initial data extraction. The two reviewers discussed the results of these five papers, and any discrepancies arising were resolved through consensus. After that, they continued to work on the data extraction of the rest of the papers. After finishing data extraction of all papers, they discussed all results, and consensus was achieved through discussions. A data extraction form was used, which included reference ID, first author, publication year, study year, title, country, study design, participants, sample size, parental acceptance or hesitancy rates, uptake rates in the previous flu season or lifetime among children aged 6–59 months, and other relevant findings on associated factors, attitude, and perception.

2.5. Quality Assessment

The information from the included articles was assessed using the Mixed-Method Appraisal Tool with detailed descriptions of the rating [31]. For quantitative studies, there are four assessment criteria: (1) whether the research question can be addressed using the sampling strategy; (2) whether the sample is representative of the population under study; (3) whether appropriate measurements are used, e.g., clear origin, reliability, and validity; (4) whether there is an acceptable response (at least 60%). For qualitative studies, there are also four assessment criteria: (1) whether the sources of qualitative data are relevant to address the research question; (2) whether the process for analysing qualitative data is relevant to address the research question; (3) whether appropriate consideration is given to how findings relate to the context, e.g., the setting, in which the data were collected; (4) whether appropriate consideration is given to how findings relate to researchers’ influence, e.g., via their interactions with participants. For mixed-method studies, in addition to the aforementioned criteria for the quantitative and qualitative studies, there are other three criteria: (1) whether the mixed-method research design is relevant to address the qualitative and quantitative research questions; (2) whether the integration of qualitative and quantitative data (or results) is relevant to address the research question; (3) whether appropriate consideration is given to the limitations associated with this integration, e.g., the divergence of qualitative and quantitative data. For each criterion, “Yes” or “No” is given as the rating [31]. Two authors (P.S.-f.C. and J.K.) independently assessed the quality of the included studies. Similar to data extraction, five papers were randomly selected for initial quality assessment. The two reviewers discussed the results of these five papers, and any discrepancies that arose were resolved through consensus. After that, they continued to work on the quality assessment of the rest of the papers. After finishing the quality assessment of all papers, they discussed all results, and consensus was achieved through discussions.

2.6. Statistical Analysis

Frequencies and percentages were used to summarise the characteristics of included studies. Random-effects models were used to generate the pooled uptake rates of children aged 6–59 months in the last flu season and lifetime, parental acceptance, and parental hesitancy. Q-test and I2 test were employed to assess heterogeneity among studies. The parental hesitancy rate was computed using the formula (100-parental acceptance rate) for studies that only provided information on the parental acceptance rate. Likewise, the parental acceptance rate was computed using the formula (100-parental hesitancy rate) for studies that only provided information on the parental hesitancy rate.
In order to determine if study characteristics could explain the variability between studies, subgroup analyses and meta-regression were conducted. This included study year (2010 or before, 2011–2015, 2016–2019, and 2020 or after), region (Asia, Americas, Europe, and Oceania), and sample size (≤1000 and >1000). In order to test whether the uptake of SIV in the last flu season and lifetime among children aged 6–59 months, parental acceptance, and parental hesitancy varied according to the selected study characteristics, univariate meta-regression was performed. Study characteristics were then included in the multivariable meta-regression if they were significant (p < 0.05) in the univariate analysis.
The presence of publication bias was visualised using funnel plots, and Egger’s linear regression test was performed. Meta-prop package (method = Inverse and summary measure = PLOGIT) was adopted in R Studio (version 4.2.1, https://cran.r-project.org/bin/windows/base/old/4.2.1/, accessed on 1 May 2023) to conduct the meta-analyses.
Additionally, other key findings on associated factors of parental acceptance, parental hesitancy, and uptake of SIV in the last season and lifetime among children aged 6–59 months, as well as parental attitudes and perceptions, were summarised thematically.

3. Results

3.1. Identification of Studies

The initial search returned 3901 citations, and 2242 remained after excluding duplicates (Figure 1). After that, we further removed 2179 articles after screening for titles and abstracts. We performed full-text screening on 63 articles, of which 27 articles were excluded because they did not meet the selection criteria.

3.2. Overview of Included Studies

A total of 36 studies published from 2004 to 2023 were finally analysed and summarised [14,15,16,17,18,19,20,21,23,24,25,26,27,28,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53] (Table 1). Most of the studies were performed in Asia (n = 15, 42%) and the Americas (n = 14, 39%), followed by Europe (n = 5, 14%) and Oceania (n = 2, 6%). These studies consist of 33 quantitative studies, 2 qualitative studies, and 1 mixed-method study. The total sample size is 68,567. Regarding study years, 14 studies were conducted before 2011, 9 were between 2011 and 2015, 10 were between 2016 and 2019, and 3 were in 2020 or after. Regarding the overall quality of the included studies, over 75% of them satisfied each criterion, except for the response rates in quantitative studies and issues related to researchers’ influence in qualitative studies. Less than half of the quantitative studies had a response rate higher than 60%. All qualitative studies did not have appropriate consideration given to how findings relate to researchers’ influence (Supplementary Table S1A–C).

3.3. Primary Findings

The pooled prevalence of parental acceptance, parental hesitancy, and the uptake of SIV in the last flu season and lifetime among children aged 6–59 months are presented in Figure 2A–D (forest plots), the associated factors are shown in Table 2, and parental attitudes and perceptions are presented in Table 1.

3.3.1. SIV Uptake in the Last Flu Season among Children Aged 6–59 Months

Twenty-three studies reported on the SIV uptake in the last flu season (Figure 2A). The overall uptake rate was 41% (95% CI: 33–50%), with a range of 9% to 76%, and had a significant heterogeneity (I2 = 99%, p < 0.01). The highest SIV uptake was reported in the United States (76%), followed by Argentina (73%), while the lowest uptake was observed in Thailand (9%).
To determine if the study year, area, and sample size could contribute to the observed heterogeneity among studies, meta-regression and subgroup analyses were conducted. Univariate meta-regression revealed that there was no significant association between SIV uptake in the last flu season and study year, region, and sample size. In subgroup analyses, since all heterogeneity analyses were significant (p < 0.01), no variability could be explained (Table 3 and Supplementary Figure S1A–C).
Publication bias among studies for SIV uptake in the last flu season was assessed using the funnel plot and Egger’s test. The funnel plot revealed that there was a probable publication bias toward studies with higher uptake rates using visual inspection (Figure 3A). However, Egger’s test showed no significant publication bias (p = 0.05). The adjusted uptake rate was 51% (95% CI: 41–62%) after filling in six missing studies by performing the trim-and-fill analysis.

3.3.2. SIV Uptake in Lifetime among Children Aged 6–59 Months

Five studies reported on SIV uptake in the lifetime among children (Figure 2B). The overall uptake rate was 46% (95% CI: 20–74%), ranging from 9% to 78%, and with significant heterogeneity (I2 = 99%, p < 0.01). Poland reported the highest uptake of SIV in a lifetime (78%), whilst the lowest was in Hong Kong (9%).
Univariate meta-regression revealed that there was no significant association between SIV uptake in the lifetime and the study year, region, and sample size. In subgroup analyses, however, only the study year had no significant heterogeneity, which means that only the study year explained some of the variability among studies (Table 3 and Supplementary Figure S2A–C).
Concerning publication bias, the funnel plot showed a probable publication bias toward studies with higher uptake rates using visual inspection (Figure 3B). However, Egger’s test found no significant publication bias (p = 0.34). Moreover, no adjusted uptake rate could be generated after performing the trim-and-fill analysis.

3.3.3. Parental Acceptance and Hesitancy of SIV

A total of fourteen studies were reported on parental acceptance and parental hesitancy (Figure 2C,D). The pooled prevalence of parental acceptance was 64% (95% CI: 51–75%), with a range of 15% to 88% (Figure 2C). Significant heterogeneity was found (I2 = 100%, p < 0.01). Canada reported the highest parental acceptance (88%), followed by the United States (87%) and South Korea (84%), whilst the Netherlands reported the lowest parental acceptance (15%). The pooled prevalence of parental hesitancy was 34% (95% CI: 22–48%), with a range of 11% to 85% (Figure 2D). Significant heterogeneity was also found (I2 = 100%, p < 0.01). The Netherlands reported the highest parental hesitancy (85%), while the lowest was found in Canada (12%) and the United States (11%).
Univariate meta-regression revealed that there was a significant association between parental acceptance and hesitancy and study region (p = 0.04, p = 0.02). The Americas had a higher parental acceptance than Asia (79% vs. 60%) and lower parental hesitancy than Asia (17% vs. 40%). In subgroup analyses, since all heterogeneity analyses were significant (p < 0.01), no variability could be explained. (Table 3 and Supplementary Figures S3A–C and S4A–C).
The funnel plot revealed a probable publication bias toward studies with low acceptance rates and high hesitancy rates (Figure 3C,D). However, Egger’s test showed no significant publication bias in parental acceptance and parental hesitancy (p = 0.39 and 0.35). Nevertheless, the adjusted acceptance and hesitancy rates were 46% (95% CI: 30–62%) and 54% (95% CI: 37–71%) after filling in six missing studies in acceptance and hesitancy using the trim-and-fill analyses.

3.3.4. Factors Associated with Parental Acceptance/Hesitancy of SIV, and SIV Uptake in Children Aged 6–59 Months

Thirty-one studies reported on the factors associated with SIV (uptake in the last flu season, uptake in lifetime, acceptance/hesitancy), as shown in Table 2. Parental education level was a strong predictor reported in nine studies, with one study reporting a negative association [44] and some reporting a positive association with acceptance and uptake [19,20,37,38,40,45,50]. Household income [14,36,37,38,40,41,44,50] and having chronic diseases/comorbidities [35,36,41,47,48,51,52] were also important predictors of vaccine acceptance and uptake. The age of children had a positive association with vaccine acceptance/uptake [41,50] but a negative association in others [44,45,51,52]. Parental age was also a significant predictor of vaccine acceptance/hesitancy/uptake [19,25,35,36,38,44,45,50]. The cost of the vaccine had a negative association with acceptance and uptake [16,20,38,44,50,53]. Perceived susceptibility [35,41,45,48], perceived severity [41,43], perceived benefits [14,19,25,35,36,37,40,41,44,45,48,51], self-efficacy to receive vaccination [36,41], and cues to action [14,16,20,21,35,36,40,42,44,45,46,47,48] were also strong positive predictors of parental acceptance and the uptake of SIV among children. Nonetheless, perceived barriers such as serious side effects and safety concerns about the vaccines and inconvenience of vaccination centres were associated with higher parental hesitancy [28,35,40,45,48]. Other reported factors included ethnicity [51,54], employment status [25,35,38], the belief that SIV is the social norm [17,28,45], and awareness that children aged 5 years are the priority group [16,44,46].

3.3.5. Parental Attitudes and Perceptions of SIV

A total of 17 studies reported parental attitudes and perceptions of SIV (Table 1). One revealed that the majority of the parents (about 90%) were aware of SIV [46], but another qualitative study showed that parents lacked knowledge about SIV [49]. The cost of the vaccine was an important issue mentioned in several studies [17,23,24,37,43]. SIV was perceived as safe, effective, and important [14,17,18,23,24,25,28,37,43,45,49]. However, worries about side effects and doubts about vaccine effectiveness were also reported [17,18,23,24,25,28,33,37,45,49]. The convenience of taking up SIV was also frequently discussed, with parents in some studies reporting that it was easy to take up SIV [17,24,28,45], but inconvenience was also reported in a few studies [37,49]. The belief that SIV was the social norm (e.g., many parents arranged SIV for their children) was revealed in various studies [18,23,24,25,49]. Nonetheless, worrying that their children could catch the flu from the vaccine was mentioned by parents [26,27,28,43]. Studies showed that parents were aware that the government recommended SIV for children aged less than 5 years or that physicians gave them the recommendations [14,23,24,25,27,33,37,45,49]. On the other hand, parents also thought that it was too young for their child to receive the SIV, and the vaccine would have a negative effect in the interactions with other vaccines to be received by the child [23,24,25]. Parents also had a high perceived self-efficacy in receiving SIV, as they believed that they would be able to get their child vaccinated if they desire to do so [23,24,25].

4. Discussion

To our knowledge, this is the first systematic review and meta-analysis to summarise evidence on SIV among children aged 6–59 months. This study revealed the pooled prevalence of parental acceptance, parental hesitancy, and the uptake of SIV in the last flu season and lifetime among children aged 6–59 months. Then, it assessed factors associated with SIV and parental attitudes and perceptions of SIV. Moreover, a reproducible search strategy with a well-established keyword system was employed for the identification of studies from key databases. All these are contributions to the literature.
This review found that the uptake of SIV in the last flu season was 41% (95% CI: 33–50%), SIV uptake in a lifetime was 46% (95% CI: 20–74%), parental acceptance was 64% (95% CI: 51–75%), and parental hesitancy was 34% (95% CI: 22–48%). Associated factors of the uptake, acceptance, or hesitancy included the age of the children or parents, parental education level, household income level, ethnicity, and other modifiable factors, including perceived benefits, perceived barriers, perceived severity, perceived susceptibility, and cues to action related to SIV.
Although 64% of the parents were willing to vaccinate their children, only 41% received SIV in the last flu season. This uptake rate is much lower than the target influenza vaccine coverage rate (VCR) of 75% recommended by the WHO [13]. This uptake is also slightly lower than that of their older counterparts (45.1–52.8%) [54,55]. This shows that there is a large room for improvement in the uptake of SIV in young children. Specific barriers to parents’ acceptance of SIV in their young children included their concerns that it was too young for their children to receive SIV and that SIV would have a negative effect in interaction with other vaccines to be received by the child [23,24,25]. Future SIV promotion programs should address these specific barriers in order to reduce parents’ concerns. For instance, supporting evidence emphasizing the safety of SIV in young children should be included in the promotion programs.
Additionally, meta-regression results showed that parental acceptance/hesitancy varied in different regions. The Americas had a higher acceptance than Asia (79% vs. 60%) and lower hesitancy than Asia (17% vs. 40%). The observed differences could be explained by the factors at the individual level and policy level. At the individual level, this study showed that a higher number of studies conducted in Asia (n = 6) than Americas (n = 3) reported perceived side effects of SIV as an important factor for acceptance of SIV. Additionally, the parental belief that it is too young for their child to receive SIV and SIV would have a negative effect in interaction with other vaccines to be received by the child were only reported in studies conducted in Asia [23,24,25]. Furthermore, these findings may be explained by the different vaccination policies in various countries. In the United States and Canada, SIV is included in the subsidised childhood immunisation scheme and free for children aged 6–59 months [56,57]. However, in countries in Asia, such as China and Singapore, SIV is not part of the subsidised childhood immunisation scheme, and it needs to be paid for out of pocket [40,46]. Health authorities in these Asian countries should consider providing subsidies for children aged 6–59 months to receive SIV.
Associated factors of the uptake/acceptance/hesitancy of SIV could be mainly categorised into individual and interpersonal levels based on the socioecological model [58]. Factors at the individual level included sociodemographics, such as the age of the children or parents, parental education level, household income level, ethnicity, and others. Older parents, lower parental education level, and household income were more consistently found to be negatively associated with uptake and acceptance. Therefore, in order to achieve the VCR (75%) recommended by the WHO [13], for successful vaccination programs in the future, such sociodemographic factors should be considered and incorporated when designing health promotion programs or targeted interventions. Other factors at the individual level also included some modifiable factors, such as perceived benefits, perceived barriers, perceived severity, and perceived susceptibility. Previous studies showed that interventions targeting modifiable factors (e.g., perceived benefits and perceived barriers) are effective in increasing vaccination uptake [59,60,61]. Factors at the interpersonal level included the influences of others (e.g., relatives/friends/spouses/health professionals). The study results consistently found that support from significant others and recommendations from health professionals to vaccinate their children had positive influences on parental decisions. Therefore, involving significant others and health professionals should be one of the core components in future health promotion programs or interventions for SIV among children.
This study also attempted to compare the uptake/acceptance/hesitancy of SIV before and during the coronavirus disease 2019 (COVID-19) pandemic. The interruptions in vaccination service provision (e.g., COVID-19 control measures and changes in the priority of health services) might play a role in the changes in the uptake/acceptance/hesitancy of SIV among children. Nonetheless, it did not show significant differences in the uptake/acceptance/hesitancy of SIV in this study. However, such results should be interpreted cautiously because there was a limited number of studies (n = 3) that were conducted during the COVID-19 pandemic, and thus, the impact of COVID-19 on children’s SIV was unclear. On the other hand, individual studies including older children (>59 months old) consistently reported a significant increase in parental acceptance (1.48–3.43-fold higher) after the COVID-19 outbreak [62,63,64]. For instance, one Chinese study found that parents were more willing to vaccinate their children against seasonal influenza than the time before the COVID-19 pandemic (68.4% vs. 35.2%) [62]. In Switzerland, compared to the time before the COVID-19 pandemic, about a two-fold increase in parental acceptance of SIV for their children was observed during the pandemic (17% vs. 7.2%) [63]. A similar trend was also reported among parents in Saudi Arabia [64]. Nevertheless, the above studies included children aged older than 59 months. Whether there is a change in the uptake/acceptance of SIV for children aged 6–59 months is still unclear.
Some studies suggested that certain strategies or interventions could increase SIV among children, including those conducted after the COVID-19 outbreak. One study showed that increasing the frequency of recommendations to receive SIV by health professionals could significantly increase SIV uptake among children [65]. Parental acceptance of SIV could be increased by offering free vaccination [62]. A review study revealed that vaccination reminders and education directed at either parents or healthcare providers, as well as via vaccination-related clinic process changes significantly improved SIV by 60% among children [66]. Several studies were conducted during the COVID-19 pandemic attempting to maintain or enhance children’s vaccination. These studies suggested using innovative approaches may be useful strategies for the post-pandemic period, such as using utilizing online technologies to remind parents and update them parents about their children’s vaccination status and remind them about the vaccination schedule [67,68,69], providing phone counselling interventions for children’s vaccination in parents [70], using telemedicine to provide necessary health information to assist parents in achieving self-efficacy and making decisions for their children’s vaccination [67,68,69,70,71,72,73], and using a chatbot real-time consultation messenger service to increase in parents’ motivation and self-efficacy to vaccinate their children [73].
Although this study provides valuable insights into parental acceptance/hesitancy and SIV uptake in the last flu season and lifetime among children aged 6–59 months, it has several limitations. First, high heterogeneity existed regarding the pooled prevalence of parental acceptance/hesitancy and uptake of SIV among children aged 6–59 months. The high heterogeneity could not be fully addressed despite subgroup analysis being performed. Nonetheless, these studies were from different countries/regions with different vaccination policies, and various types of study methodologies were used, which made heterogeneity inevitable. Second, data collected in the included studies in this review were self-reported, and recall and social desirability bias might exist. Third, since all studies were cross-sectional, no causal relationship between uptake/acceptance/hesitancy with factors could be established. Fourth, the exclusion of government documents/reports and newspapers without peer review might be justifiable for scientific rigour, but it is acknowledged that this decision might limit the inclusion of valuable information.

5. Conclusions

This study revealed the pooled prevalence of parental acceptance, parental hesitancy, and the uptake of SIV in the last flu season and lifetime, as well as their associated factors among children aged 6–59 months. The results revealed that the uptake of SIV in the last flu season, SIV uptake in a lifetime, parental acceptance, and parental hesitancy, were 41%, 46%, 64%, and 34%, respectively. Associated factors of the uptake, acceptance, or hesitancy included the age of the children or parents, parental education level, household income level, ethnicity, and other modifiable factors, including perceived benefits, perceived barriers, perceived severity, perceived susceptibility, and cues to action related to SIV. In order to achieve the VCR (75%) recommended by the WHO to protect children from vaccine-preventable diseases, it is crucial to implement tailored SIV interventions or programs for parents that address the factors, parental attitudes/perceptions, and specific local contexts in various regions or countries.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/vaccines11081360/s1. Table S1 (A): Quality assessment of quantitative studies; (B): Quality assessment of qualitative studies; (C): Quality assessment of mixed-method study; Figure S1 (A): Forest plot of subgroup analysis of the uptake in the last flu season by year; (B): Forest plot of subgroup analysis of the uptake in the last flu season by region; (C): Forest plot of subgroup analysis of the uptake in the last flu season by sample size; Figure S2 (A): Forest plot of subgroup analysis of the uptake in lifetime by year; (B): Forest plot of subgroup analysis of the uptake in lifetime by region; (C): Forest plot of subgroup analysis of the uptake in lifetime by sample size; Figure S3 (A): Forest plot of subgroup analysis of the parental acceptance by year; (B): Forest plot of subgroup analysis of the parental acceptance by region; (C): Forest plot of subgroup analysis of the parental acceptance by sample size; Figure S4 (A): Forest plot of subgroup analysis of the parental hesitancy by year; (B): Forest plot of subgroup analysis of the parental hesitancy by region; (C): Forest plot of subgroup analysis of the parental hesitancy by sample size

Author Contributions

Conceptualisation: P.S.-f.C. and Z.W.; methodology and analysis: P.S.-f.C. and Z.W.; formal analysis: P.S.-f.C., Z.W., Y.F. and J.K.; visualisation: P.S.-f.C. and J.K.; writing—original draft preparation: P.S.-f.C., Z.W., Y.F., J.K., S.C. and X.L.; writing—review and editing: P.S.-f.C., Z.W., Y.F., J.K., S.C., X.L. and P.K.-h.M. All authors have read and agreed to the published version of the manuscript.

Funding

This study was supported by internal funding from the Centre for Health Behaviours Research, The Chinese University of Hong Kong.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Data supporting this systematic review are available in the reference section. In addition, the analysed data used in this systematic review are available from the author upon reasonable request.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. World Health Organization. Influenza vaccines: Vaccins antigrippaux. Wkly. Epidemiol. Rec. 2005, 33, 279–287. [Google Scholar]
  2. Willis, G.A.; Preen, D.B.; Richmond, P.C.; Jacoby, P.; Effler, P.V.; Smith, D.W.; Robins, C.; Borland, M.L.; Levy, A.; Keil, A.D.; et al. The impact of influenza infection on young children, their family and the health care system. Influ. Other Respir. Viruses 2018, 13, 18–27. [Google Scholar] [CrossRef] [Green Version]
  3. Lafond, K.E.; Nair, H.; Rasooly, M.H.; Valente, F.; Booy, R.; Rahman, M.; Kitsutani, P.; Yu, H.; Guzman, G.; Coulibaly, D.; et al. Global Role and Burden of Influenza in Pediatric Respiratory Hospitalizations, 1982–2012: A Systematic Analysis. PLoS Med. 2016, 13, e1002060. [Google Scholar] [CrossRef] [Green Version]
  4. Nair, H.; Brooks, W.A.; Katz, M.; Roca, A.; Berkley, J.A.; Madhi, S.A.; Simmerman, J.M.; Gordon, A.; Sato, M.; Howie, S.; et al. Global burden of respiratory infections due to seasonal influenza in young children: A systematic review and meta-analysis. Lancet 2011, 378, 1917–1930. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  5. Wang, H.; Naghavi, M.; Allen, C.; Barber, R.M.; Bhutta, Z.A.; Carter, A.; Casey, D.C.; Charlson, F.J.; Chen, A.Z.; Coates, M.M.; et al. Global, regional, and national life expectancy, all-cause mortality, and cause-specific mortality for 249 causes of death, 1980–2015: A systematic analysis for the Global Burden of Disease Study 2015. Lancet 2016, 388, 1459–1544. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  6. Brotherton, J.; Wang, H.; Schaffer, A.; Quinn, H.; Menzies, R.; Hull, B.; Lawrence, G.; Wood, J.; Wood, N.; Rosewell, A.; et al. Vaccine preventable disease and vaccination coverage in Australia 2003 to 2005. Commuity Dis. Intellance 2007, 31 (Suppl. S1), S1–S152. [Google Scholar]
  7. Centers for Disease Control and Prevention. Update: Influenza activity—United States, 2009–10 season. Morb. Mortal. Wkly. Rep. 2010, 59, 901–908. [Google Scholar]
  8. Mantel, C.; Chu, S.Y.; Hyde, T.B.; Lambach, P. Seasonal influenza vaccination in middle-income countries: Assessment of immunization practices in Belarus, Morocco, and Thailand. Vaccine 2019, 38, 212–219. [Google Scholar] [CrossRef]
  9. Harper, S.A.; Bradley, J.S.; Englund, J.A.; File, T.M.; Gravenstein, S.; Hayden, F.G.; McGeer, A.J.; Neuzil, K.M.; Pavia, A.T.; Tapper, M.L.; et al. Seasonal Influenza in Adults and Children-Diagnosis, Treatment, Chemoprophylaxis, and Institutional Outbreak Management: Clinical Practice Guidelines of the Infectious Diseases Society of America. Clin. Infect. Dis. 2009, 48, 1003–1032. [Google Scholar] [CrossRef]
  10. Hurwitz, E.S.; Haber, M.; Chang, A.; Shope, T.; Teo, S.; Ginsberg, M.; Waecker, N.; Nancy, J.C. Effectiveness of influenza vaccination of day care children in reducing influenza-related morbidity among household contacts. JAMA J. Am. Med. Assoc. 2000, 284, 1677–1682. [Google Scholar] [CrossRef] [Green Version]
  11. Moreno, J.; De Hoz, F.; Rico, A.; Cotes, K.; Porras, A. Vaccine effectiveness against influenza: Meta analysis literature. Biomédica 2009, 29, 87–97. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  12. Shono, A.; Kondo, M. Factors associated with seasonal influenza vaccine uptake among children in Japan. BMC Infect. Dis. 2015, 15, 72. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  13. World Health Organization. Vaccines against influenza WHO position paper. Wkly. Epidemiol. Rec. 2012, 87, 461–476. [Google Scholar]
  14. Fisher, W.A.; Gilca, V.; Murti, M.; Orth, A.; Garfield, H.; Roumeliotis, P.; Rampakakis, E.; Brown, V.; Yaremko, J.; Buynder, B.V.; et al. Parental Attitudes and Perceptions of Support after Brief Clinician Intervention Predict Intentions to Accept the Adjuvanted Seasonal Influenza Vaccination: Findings from the Pediatric Influenza Vaccination Optimization Trial (PIVOT)-I. Vaccines 2022, 10, 1957. [Google Scholar] [CrossRef]
  15. Zhang, H.; Ren, X.; Tian, K.; Yu, J.; Zhu, A.; Zhang, L.; Gao, G.; Li, Z. The Impact and Vaccination Coverage of Seasonal Influenza among Children Aged 6–59 Months in China in 2017–2018: An Internet Panel Survey. Vaccines 2022, 10, 630. [Google Scholar] [CrossRef]
  16. Frawley, J.E.; McManus, K.; McIntyre, E.; Seale, H.; Sullivan, E. Uptake of funded influenza vaccines in young Australian children in 2018; parental characteristics, information seeking and attitudes. Vaccine 2020, 38, 180–186. [Google Scholar] [CrossRef] [PubMed]
  17. Wei, Z.; Sun, X.; Yang, Y.; Zhan, S.; Fu, C. Seasonal influenza vaccine hesitancy profiles and determinants among Chinese children’s guardians and the elderly. Expert Rev. Vaccines 2021, 20, 601–610. [Google Scholar] [CrossRef]
  18. van Lier, A.; Ferreira, J.A.; Mollema, L.; Sanders, E.A.; de Melker, H.E. Intention to vaccinate universally against varicella, rotavirus gastroenteritis, meningococcal B disease and seasonal influenza among parents in the Netherlands: An internet survey. BMC Res. Notes 2017, 10, 672. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  19. Wu, J.; Wei, Z.; Yang, Y.; Sun, X.; Zhan, S.; Jiang, Q.; Fu, C. Gap between cognitions and behaviors among children’s guardians of influenza vaccination: The role of social influence and vaccine-related knowledge. Hum. Vaccines Immunother. 2023, 19, 2166285. [Google Scholar] [CrossRef] [PubMed]
  20. Thanee, C.; Kittikraisak, W.; Sinthuwattanawibool, C.; Roekworachai, K.; Klinklom, A.; Kornsitthikul, K.; Jirasakpisarn, S.; Srirompotong, U.; Chittaganpitch, M.; Dawood, F.S.; et al. Knowledge, attitude/perception, and practice related to seasonal influenza vaccination among caregivers of young Thai children: A cross-sectional study. PLoS ONE 2021, 16, e0253561. [Google Scholar] [CrossRef]
  21. Nowalk, M.P.; Lin, C.J.; Zimmerman, R.K.; Ko, F.S.; Hoberman, A.; Raymund, M.; Kearney, D.H.; Greenberg, D.P. Changes in parents’ perceptions of infant influenza vaccination over two years. J. Natl. Med. Assoc. 2007, 99, 636–641. [Google Scholar] [PubMed]
  22. Imburgia, T.M.; Hendrix, K.S.; Donahue, K.L.; Sturm, L.A.; Zimet, G.D. Predictors of influenza vaccination in the U.S. among children 9–13 years of age. Vaccine 2017, 35, 2338–2342. [Google Scholar] [CrossRef]
  23. Lau, J.T.F.; Mo, P.K.H.; Cai, Y.S.; Tsui, H.Y.; Choi, K.C. Coverage and parental perceptions of influenza vaccination among parents of children aged 6 to 23 months in Hong Kong. BMC Public Health 2013, 13, 1026. [Google Scholar] [CrossRef] [Green Version]
  24. Wu, A.M.S.; Lau, J.T.F.; Ma, Y.L.; Lau, M.M.C. Prevalence and associated factors of seasonal influenza vaccination among 24-to 59-month-old children in Hong Kong. Vaccine 2015, 33, 3556–3561. [Google Scholar] [CrossRef]
  25. Wu, A.M.S.; Lau, J.T.F.; Ma, Y.L.; Cheng, K.M.; Lau, M.M.C. A longitudinal study using parental cognitions based on the theory of planned behavior to predict childhood influenza vaccination. J. Infect. Public Health 2020, 13, 970–979. [Google Scholar] [CrossRef]
  26. Bauer, K.E.; Agruss, J.C.; Mayefsky, J.H. Partnering with parents to remove barriers and improve influenza immunization rates for young children. J. Am. Assoc. Nurse Pract. 2021, 33, 470–475. [Google Scholar] [CrossRef] [PubMed]
  27. Biezen, R.; Grando, D.; Mazza, D.; Brijnath, B. Why do we not want to recommend influenza vaccination to young children? A qualitative study of Australian parents and primary care providers. Vaccine 2018, 36, 859–865. [Google Scholar] [CrossRef]
  28. Daley, M.F.; Crane, L.A.; Chandramouli, V.; Beaty, B.L.; Barrow, J.; Allred, N.; Berman, S.; Kempe, A. Misperceptions about influenza vaccination among parents of healthy young children. Clin. Pediatr. 2007, 46, 408–417. [Google Scholar] [CrossRef]
  29. Smith, L.E.; Amlot, R.; Weinman, J.; Yiend, J.; Rubin, G.J. A systematic review of factors affecting vaccine uptake in young children. Vaccine 2017, 35, 6059–6069. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  30. Moher, D.; Shamseer, L.; Clarke, M.; Ghersi, D.; Liberati, A.; Petticrew, M.; Shekelle, P.; Stewart, L.S. Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015 statement. Rev. Esp. Nutr. Hum. Die. 2016, 20, 148–160. [Google Scholar] [CrossRef] [Green Version]
  31. Pace, R.; Pluye, P.; Bartlett, G.; Macaulay, A.C.; Salsberg, J.; Jagosh, J.; Seller, R. Testing the reliability and efficiency of the pilot Mixed Methods Appraisal Tool (MMAT) for systematic mixed studies review. Int. J. Nurs. Stud. 2012, 49, 47–53. [Google Scholar] [CrossRef] [PubMed]
  32. Brown, C.; Clayton-Boswell, H.; Chaves, S.S.; Prill, M.M.; Iwane, M.K.; Szilagyi, P.G.; Edwards, K.M.; Staat, M.A.; Weinberg, G.A.; Fairbrother, G.; et al. Validity of parental report of influenza vaccination in young children seeking medical care. Vaccine 2011, 29, 9488–9492. [Google Scholar] [CrossRef]
  33. Bults, M.; Beaujean, D.J.M.A.; Richardus, J.H.; van Steenbergen, J.E.; Voeten, H.A.C.M. Pandemic influenza A (H1N1) vaccination in The Netherlands: Parental reasoning underlying child vaccination choices. Vaccine 2011, 29, 6226–6235. [Google Scholar] [CrossRef] [PubMed]
  34. Chantler, T.; Pace, D.; Wright, A.; Pollard, A.J.; Yu, L.M.; Nguyen-Van-Tam, J.S.; MacDonald, N. Uptake and acceptability of influenza vaccination in day nursery children. Community Pract. 2007, 80, 32–36. [Google Scholar]
  35. Chen, M.F.; Wang, R.H.; Schneider, J.K.; Tsai, C.T.; Jiang, D.D.S.; Hung, M.N.; Lin, L.J. Using the Health Belief Model to Understand Caregiver Factors Influencing Childhood Influenza Vaccinations. J. Community Health Nurs. 2011, 28, 29–40. [Google Scholar] [CrossRef]
  36. Chen, C.H.; Chiu, P.J.; Chih, Y.C.; Yeh, G.L. Determinants of influenza vaccination among young Taiwanese children. Vaccine 2015, 33, 1993–1998. [Google Scholar] [CrossRef]
  37. Choi, A.; Kim, D.H.; Kim, Y.K.; Eun, B.W.; Jo, D.S. The impact of an educational intervention on parents’ decisions to vaccinate their <60-monthold children against influenza. Korean J. Pediatr. 2017, 60, 254–260. [Google Scholar]
  38. Ganczak, M.; Dmytrzyk-Daniłów, G.; Karakiewicz, B.; Korzeń, M.; Szych, Z. Determinants influencing self-paid vaccination coverage, in 0-5 years old Polish children. Vaccine 2013, 31, 5687–5692. [Google Scholar] [CrossRef]
  39. Gentile, A.; Juárez, M.; Hernandez, S.; Moya, A.; Bakir, J.; Lucion, M. Influenza vaccine: Delayed vaccination schedules and missed opportunities in children under 2 years old. Vaccine 2015, 33, 3913–3917. [Google Scholar] [CrossRef]
  40. Han, K.; Hou, Z.; Tu, S.; Wang, Q.; Hu, S.; Xing, Y.; Du, J.; Zang, S.; Chantler, T.; Larson, H. Childhood Influenza Vaccination and Its Determinants during 2020-2021 Flu Seasons in China: A Cross-Sectional Survey. Vaccines 2022, 10, 1994. [Google Scholar] [CrossRef] [PubMed]
  41. He, L.; Liao, Q.Y.; Huang, Y.Q.; Feng, S.; Zhuang, X.M. Parents’ Perception and their Decision on their Children’s Vaccination Against Seasonal Influenza in Guangzhou. Chin. Med. J. 2015, 128, 327–341. [Google Scholar] [CrossRef] [PubMed]
  42. Hemingway, C.O.; Poehling, K.A. Change in recommendation affects influenza vaccinations among children 6 to 59 months of age. Pediatrics 2004, 114, 948–952. [Google Scholar] [CrossRef]
  43. Humiston, S.G.; Lerner, E.; Hepworth, E.; Blythe, T.; Goepp, J.G. Parent opinions about universal influenza vaccination for infants and toddlers. Arch. Pediatr. Adolesc. Med. 2005, 159, 108–112. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  44. Lai, X.; Li, M.; Hou, Z.; Guo, J.; Zhang, H.; Wang, J.; Fang, H. Factors associated with caregivers’ hesitancy to vaccinate children against influenza: A cross-sectional survey in China. Vaccine 2022, 40, 3975–3983. [Google Scholar] [CrossRef]
  45. Lau, J.T.; Wu, A.M.; Ma, Y.L.; Lau, M.M. Associated Factors of Behavioral Intention Regarding Childhood Influenza Vaccination Among Parents of Ever-Vaccinated and Never-Vaccinated 24-to 59-Month-Old Children in Hong Kong. Asia Pac. J. Public Health 2021, 33, 262–272. [Google Scholar] [CrossRef]
  46. Low, M.S.; Tan, H.; Hartman, M.; Tam, C.C.; Hoo, C.; Lim, J.; Chiow, S.; Lee, S.; Thing, R.; Cai, M.; et al. Parental perceptions of childhood seasonal influenza vaccination in Singapore: A cross-sectional survey. Vaccine 2017, 35, 6096–6102. [Google Scholar] [CrossRef]
  47. Ma, K.K.; Schaffner, W.; Colmenares, C.; Howser, J.; Jones, J.; Poehling, K.A. Influenza vaccinations of young children increased with media coverage in 2003. Pediatrics 2006, 117, E157–E163. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  48. Nowalk, M.P.; Zimmerman, R.K.; Lin, C.J.; Ko, F.S.; Raymund, M.; Hoberman, A.; Kearney, D.H.; Greenberg, D.P. Parental perspectives on influenza immunization of children aged 6 to 23 months. Am. J. Prev. Med. 2005, 29, 210–214. [Google Scholar] [CrossRef]
  49. Price, T.; McColl, E.; Visram, S. Barriers and facilitators of childhood flu vaccination: The views of parents in North East England. J. Public Health 2022, 30, 2619–2626. [Google Scholar] [CrossRef]
  50. Schuller, K.A.; Probst, J.C. Factors associated with influenza vaccination among US children in 2008. J. Infect. Public Health 2013, 6, 80–88. [Google Scholar] [CrossRef] [Green Version]
  51. Schellenberg, N.; Petrucka, P.; Dietrich Leurer, M.; Crizzle, A.M. Determinants of vaccine refusal, delay and reluctance in parents of 2-year-old children in Canada: Findings from the 2017 Childhood National Immunization Coverage Survey (cNICS). Travel Med. Infect. Dis. 2023, 53, 102584. [Google Scholar] [CrossRef]
  52. Shinall, M.C.; Plosa, E.J.; Poehling, K.A. Validity of parental report of influenza vaccination in children 6 to 59 months of age. Pediatrics 2007, 120, e783–e787. [Google Scholar] [CrossRef]
  53. Williams, J.T.; Rice, J.D.; Lou, Y.; Soderborg, T.K.; Bayliss, E.A.; Federico, S.G.; Hambidge, S.J.; O’Leary, S.T. Parental Vaccine Hesitancy and Risk of Pediatric Influenza Under-Vaccination in a Safety-Net Health Care System. Acad Pediatr. 2021, 21, 1126–1133. [Google Scholar] [CrossRef] [PubMed]
  54. Smith, L.E.; Webster, R.K.; Weinman, J.; Amlot, R.; Yiend, J.; Rubin, G.J. Psychological factors associated with uptake of the childhood influenza vaccine and perception of post-vaccination side-effects: A cross-sectional survey in England. Vaccine 2017, 35, 1936–1945. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  55. Zhai, Y.; Santibanez, T.A.; Kahn, K.E.; Srivastav, A. Parental-Reported Full Influenza Vaccination Coverage of Children in the US. Am. J. Prev. Med. 2017, 52, e103–e113. [Google Scholar] [CrossRef] [Green Version]
  56. Grohskopf, L.A.; Blanton, L.H.; Ferdinands, J.M.; Chung, J.R.; Broder, K.R.; Talbot, H.K.; Morgan, R.L.; Fry, A.M. Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices—United States, 2022–23 Influenza Season. Mmwr-Morb. Mortal. W. 2022, 71, 1–32. [Google Scholar] [CrossRef]
  57. Government of Canada. Public Funding for Influenza Vaccination by Province/Territory (as of June 2023). Available online: https://www.canada.ca/en/public-health/services/provincial-territorial-immunization-information/public-funding-influenza-vaccination-province-territory.html (accessed on 15 May 2023).
  58. Mcleroy, K.R.; Bibeau, D.; Steckler, A.; Glanz, K. An Ecological Perspective on Health Promotion Programs. Health Educ. Q. 1988, 15, 351–377. [Google Scholar] [CrossRef]
  59. Wang, Z.; Fang, Y.; Chan, P.S.F.; Chidgey, A.; Fong, F.; Ip, M.; Lau, J.T. Effectiveness of a Community-Based Organization-Private Clinic Service Model in Promoting Human Papillomavirus Vaccination among Chinese Men Who Have Sex with Men. Vaccines 2021, 9, 1218. [Google Scholar] [CrossRef] [PubMed]
  60. Chan, P.S.F.; Fang, Y.; Chidgey, A.; Fong, F.; Ip, M.; Wang, Z. Would Chinese Men Who Have Sex With Men Take Up Human Papillomavirus (HPV) Screening as an Alternative Prevention Strategy to HPV Vaccination? Front. Med. 2022, 9, 904873. [Google Scholar] [CrossRef] [PubMed]
  61. Mehta, P.; Sharma, M.; Lee, R.C. Designing and Evaluating a Health Belief Model-Based Intervention to Increase Intent of Hpv Vaccination among College Males. Int. Q. Community Health Educ. 2014, 34, 101–117. [Google Scholar] [CrossRef] [PubMed]
  62. Zhou, Y.H.; Tang, J.; Zhang, J.J.; Wu, Q.S. Impact of the coronavirus disease 2019 epidemic and a free influenza vaccine strategy on the willingness of residents to receive influenza vaccines in Shanghai, China. Hum. Vaccines Immunother. 2021, 17, 2289–2292. [Google Scholar] [CrossRef] [PubMed]
  63. Seiler, M.; Goldman, R.D.; Staubli, G.; Hoeffe, J.; Gualco, G.; Manzano, S. Parents’ intent to vaccinate against influenza during the COVID-19 pandemic in two regions in Switzerland. Swiss Med. Wkly. 2021, 151, w20508. [Google Scholar] [CrossRef] [PubMed]
  64. Salawati, E.; Alwafi, H.; Samannodi, M.; Minshawi, F.; Gari, A.; Abualnaja, S.; Almatrafi, M.A. Parents’ Willingness to Vaccinate Their Children Against Seasonal Influenza After the COVID-19 Pandemic in Saudi Arabia: A Retrospective Cross-Sectional Survey. Patient Prefer. Adherence 2021, 15, 2821–2835. [Google Scholar] [CrossRef]
  65. Pandolfi, E.; Marino, M.G.; Carloni, E.; Romano, M.; Gesualdo, F.; Borgia Pcarloni, R.; Guarino, A.; Giannattasio, A.; Tozzi, A.E. The effect of physician’s recommendation on seasonal influenza immunization in children with chronic diseases. BMC Public Health 2012, 12, 984. [Google Scholar] [CrossRef] [Green Version]
  66. Norman, D.A.; Barnes, R.; Pavlos, R.; Bhuiyan, M.; Alene, K.A.; Danchin, M.; Seale, H.; Moore, H.C.; Blyth, C.C. Improving Influenza Vaccination in Children With Comorbidities: A Systematic Review. Pediatrics 2021, 147, e20201433. [Google Scholar] [CrossRef]
  67. Ryan, G. Challenges to Adolescent HPV Vaccination and Implementation of Evidence-Based Interventions to Promote Vaccine Uptake During the COVID-19 Pandemic: “HPV Is Probably Not at the Top of Our List”. Prev. Chronic Dis. 2022, 19, E15. [Google Scholar] [CrossRef] [PubMed]
  68. Balogun, M.; Banke-Thomas, A.; Gwacham-Anisiobi, U.; Yesufu, V.; Ubani, O.; Afolabi, B.B. Actions and Adaptations Implemented for Maternal, Newborn and Child Health Service Provision During the Early Phase of the COVID-19 Pandemic in Lagos, Nigeria: Qualitative Study of Health Facility Leaders. Ann. Glob. Health 2022, 88, 1–14. [Google Scholar] [CrossRef]
  69. Kazi, A.M.; Ahsan, N.; Mughis, W.; Jamal, S.; Allana, R.; Raza, M.; Muneer, S.; Mughal, M.A.; Kaleemuddin, H.; Sameen, F.; et al. Usability and Acceptability of a Mobile App for Behavior Change and to Improve Immunization Coverage among Children in Pakistan: A Mixed-Methods Study. Int. J. Environ. Res. Public Health 2021, 18, 9527. [Google Scholar] [CrossRef]
  70. Murthy, S.; Sawant, M.; Doreswamy, S.S.; Pothula, S.C.; Yan, S.D.; Pathani, T.S.; Thakur, D.; Rajarama Sastry Vemuri, S.; Upadhyaya, S.; Alam, S.; et al. Supporting Immunization Uptake during a Pandemic, Using Remote Phone Call Intervention among Babies Discharged from a Special Neonatal Care Unit (SNCU) in South India. Vaccines 2022, 10, 507. [Google Scholar] [CrossRef]
  71. Kovar, C.L.; Pestaner, M.; Corbett, R.W.; Rose, C.L. HPV vaccine promotion: Snapshot of two health departments during the COVID-19 pandemic. Public Health Nurs. 2021, 38, 715–719. [Google Scholar] [CrossRef]
  72. Khader, Y.S.; Maalouf, W.; Khdair, M.A.; Al-Nsour, M.; Aga, E.; Khalifa, A.; Kassasbeh, M.; El-Halabi, S.; Alfven, T.; El-Khatib, Z. Scaling the Children Immunization App (CIMA) to Support Child Refugees and Parents in the Time of the COVID-19 Pandemic: A Social Capital Approach to Scale a Smartphone Application in Zaatari Camp, Jordan. J. Epidemiol. Glob. Health 2022, 12, 7–12. [Google Scholar] [CrossRef] [PubMed]
  73. Hong, Y.J.; Piao, M.; Kim, J.; Lee, J.H. Development and Evaluation of a Child Vaccination Chatbot Real-Time Consultation Messenger Service during the COVID-19 Pandemic. Appl. Sci. 2021, 11, 12142. [Google Scholar] [CrossRef]
Vaccines 11 01360 g001
Figure 1. Flowchart of selection of included studies.
Figure 1. Flowchart of selection of included studies.
Vaccines 11 01360 g001
Vaccines 11 01360 g002aVaccines 11 01360 g002b
Figure 2. (A) Forest plot for pooled uptake rate of SIV in the last flu season; (B) forest plot for pooled uptake rate in lifetime; (C) forest plot for pooled acceptance rate of SIV; (D) forest plot for pooled hesitancy rate of SIV [14,15,16,17,18,19,20,21,23,24,25,26,28,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,50,51,52,53].
Figure 2. (A) Forest plot for pooled uptake rate of SIV in the last flu season; (B) forest plot for pooled uptake rate in lifetime; (C) forest plot for pooled acceptance rate of SIV; (D) forest plot for pooled hesitancy rate of SIV [14,15,16,17,18,19,20,21,23,24,25,26,28,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,50,51,52,53].
Vaccines 11 01360 g002aVaccines 11 01360 g002b
Vaccines 11 01360 g003aVaccines 11 01360 g003b
Figure 3. (A) Funnel plot of uptake rate of SIV in the last flu season; (B) funnel plot of uptake rate in lifetime; (C) funnel plot of acceptance rate of SIV; (D) funnel plot of hesitancy rate of SIV.
Figure 3. (A) Funnel plot of uptake rate of SIV in the last flu season; (B) funnel plot of uptake rate in lifetime; (C) funnel plot of acceptance rate of SIV; (D) funnel plot of hesitancy rate of SIV.
Vaccines 11 01360 g003aVaccines 11 01360 g003b
Table 1. Characteristics of included studies.
Table 1. Characteristics of included studies.
AuthorStudy YearCountry/
Region		Study DesignSample SizeAge of the ChildrenUptake in the Last Flu Season/Uptake in Lifetime/Acceptance/HesitancyKey Findings
Bauer et al., 2021 [26]2018USAQuantitative: cross-sectional survey1656–24 monthsUptake in the last flu season: 44%
Acceptance: 71%
Hesitancy: 11%		Uptake in the last flu season
  • Barriers: forgetfulness, unawareness that the vaccine can be given at the age of 6 months, and beliefs that the vaccine is unnecessary and causes a flu-like reaction.
  • Most helpful measures to reduce these barriers would be text message reminders, call reminders, and additional information or education on the influenza vaccine.
Biezen et al., 2018 [27]2015AustraliaQualitative: focus group506–59 monthsNA
  • Negative beliefs: the vaccine could cause influenza, and the vaccine was not necessary for their children.
  • When SIV was recommended by their doctors and the influenza vaccine was part of the immunisation schedule, the parents would consider vaccinating their children.
Brown et al., 2011 [32]2007USAQuantitative: cross-sectional survey30726–59 monthsUptake in the last flu season: 39.5%Uptake in the last flu season
  • In total, 47.5% of the children received the influenza vaccine, and 39.5% had medical record verification.
Bults et al., 2011 [33]2009The NetherlandsQuantitative: cross-sectional survey31276–59 monthsUptake in the last flu season: 36%
Uptake in the last flu season
  • Reasons for taking up SIV: do not want their child to become sick, the government recommendation, and belief that they would regret if they do not do it.
  • Reasons for refusing SIV: fear of side effects/harmful consequences, just having a bad feeling about it, and the vaccine was not thoroughly tested.
  • More decliners than accepters experienced feelings of doubt about the vaccination decision, and decliners reported more often information-seeking behaviours.
  • Decliners more frequently solicited advice from their social network than accepters.
  • Accepters more often reported social influence on their vaccination decision and experienced more negative feelings after their vaccination decision.
Chantler et al., 2007 [34]2005UKMixed-method: Semi-structured interview and cross-sectional surveySemi-structured interview: 10
Survey: 83		6–23 monthsUptake in the last flu season: 11%Uptake in the last flu season
  • Barriers: not convinced about the seriousness of paediatric influenza, difficult to differentiate influenza from other respiratory illnesses, expressed concerns about the need for annual injections and vaccine safety, and children should only be vaccinated if they are the main beneficiaries.
Chen et al., 2011 [35]2009TaiwanQuantitative: cross-sectional survey27786–36 monthsUptake in the last flu season: 60.4%Uptake in the last flu season
  • Associated factors: parental age, current employment, residence, children’s chronic diseases, hospitalisation, and influenza histories.
  • Other associated factors: perceived susceptibility, perceived benefits, perceived barriers of vaccination, and cues to action.
Chen et al., 2015 [36]2011TaiwanQuantitative: cross-sectional survey13006–36 monthsUptake in the last flu season: 50%
Acceptance: 73%
Hesitancy: 27%		Acceptance
  • Facilitators: perceived benefits, cues to action, and self-efficacy of vaccination against influenza, and children’s experience of influenza vaccinations in the last flu season.
Choi et al., 2017 [37]2015Republic of KoreaQuantitative: cross-sectional survey639<60 monthsAcceptance: 83.6%
Hesitancy: 16.4%		Acceptance:
  • Facilitators: higher income and education and physicians’ recommendation.
  • Barriers: cost of vaccination.
  • Positive beliefs: influenza vaccine can reduce the symptoms and is effective at preventing the disease and safe for children.
  • Negative beliefs: side effects of influenza vaccination, not convenient to receive the vaccination, and vaccination is not free.
Daley et al., 2007 [28]2004USAQuantitative: cross-sectional survey8396–21 monthsUptake in the last flu season: 71%Uptake in the last flu season
  • Associated factors: the belief that SIV was the social norm, anticipating immunisation barriers. Parents hold a number of misperceptions about influenza vaccination, such as influenza vaccination could cause influenza infection (70%) and was not safe (21%).
Fisher et al., 2022 [14]2016CanadaQuantitative: cross-sectional survey2076–23 monthsAcceptance: 66%
Hesitancy: 34%		Acceptance
  • Most parents considered immunisation to be safe, effective, and important; most perceived support for vaccination from significant others and clinicians.
  • Associated factors: higher income, perceived vaccine safety, perceived benefit, perceived cues to action, and perceived support from significant others.
Frawley et al., 2020 [16]2018AustraliaQuantitative: cross-sectional survey10026–59 monthsUptake in the last flu season: 52.9%Uptake in the last flu season
  • Associated factors: being a mother, not having a healthcare card, the vaccine was free, and recommended by a pharmacist
  • Negative beliefs: safety concerns of the influenza vaccine, and their child can catch influenza from the vaccine.
Ganczak et al., 2013 [38]2010PolandQuantitative: cross-sectional survey3086–59 monthsUptake in lifetime: 77.9%Uptake in lifetime
  • Parental decision was based on a healthcare worker’s recommendation.
  • Associated factors: parental age, high socioeconomic status, having one child, convenience of vaccination, and the vaccine was not free.
Gentile et al., 2015 [39]2013ArgentinaQuantitative: cross-sectional survey13506–24 monthsUptake in the last flu season: 73.1%Uptake in the last flu season
  • Factors associated with a decreased risk of delayed schedules were perception of the importance of influenza vaccination, having less than one year of age, and having received information in paediatric visits or in any media.
Han et al., 2022 [40]2021ChinaQuantitative: cross-sectional survey2081<5 yearsUptake in the last flu season: 43.63%Uptake in the last flu season
  • Facilitators included caregivers who had a bachelor’s degree or above, an annual household income of RMB <20,000, confidence in the importance, safety, and effectiveness of influenza vaccine, knowing other caregivers were vaccinating their children, and receiving positive influence from healthcare workers and family members.
  • Barriers included poor access, including conflicts between caregivers’ availability and vaccination service schedules and inconvenient transportation to the vaccination site.
He et al., 2015 [41]2013China Quantitative: cross-sectional survey3356–36 monthsUptake in the last flu season: 47.7%
Acceptance: 62.4%
Hesitancy: 37.6%		Uptake in the last flu season
  • Associated factors: household income, children’s age, social norm and perceived control, and perceived safety.
  • Associated factors: household income, children with a history of taking seasonal influenza vaccine, perceived children’s health status, worry/anxiety about their children’s influenza infection, perceived control, perceived safety, perceived benefits, social norm, and perceived severity.
Hemingway et al., 2004 [42]2003USAQuantitative: cross-sectional survey3296–59 monthsUptake in the last flu season: 18%Uptake in the last flu season
  • Associate factors: parental recall of a physician recommendation and family member vaccinated.
  • In total, 65% of parents of high-risk children did not recall a physician’s recommendation, 62% learned of influenza vaccination from the mass media, and 38% from their paediatricians
Humiston et al., 2005 [43]2004USAQuantitative: cross-sectional survey1536–23 monthsAcceptance: 78%
Hesitancy: 22%		Acceptance
  • Negative beliefs: the vaccine was not safe, and the child could catch influenza from vaccination.
  • Associated factors: perceived severity of influenza, perceived safety of the vaccine, and parental educational level.
Lai et al., 2022 [44]2019ChinaQuantitative: cross-sectional survey66686–59 monthsAcceptance: 38.6%
Hesitancy: 61.4%		Hesitancy
  • Associated factors: perceiving high importance, safety or efficacy) of SIV, knowing children as a priority group, and trusting vaccination advice from medical staff.
  • Others included: sociodemographic characteristics, such as children’s age, the number of children in the family and caregivers’ information (age, family relation, education level, basic medical insurance type, religious beliefs, income, place of residence, and province).
Lau et al., 2021 [45]2011Hong KongQuantitative: cross-sectional survey54024–59 monthsAcceptance: 68.9%
Hesitancy: 31.1%		Acceptance
  • Being a mother, having a child aged ≥48 months, and the absence of IV experience in family members were the significant background factors of parental intention in the ever-vaccinated group, while being a mother, younger, and more educated were significant factors of parental intention in the never-vaccinated group.
  • Perceived susceptibility, perceived benefit, perceived barrier, cue to action, subjective norm, and having family members vaccinated were associated with parental intention for ever-vaccinated children’s IV, while only perceived benefit and subjective norm were significant for never-vaccinated children.
Lau et al., 2013 [23]2006Hong KongQuantitative: cross-sectional survey4016–23 monthsUptake in lifetime: 9%Uptake in lifetime
  • Associated factors: physician recommendations and perceived side effects of SIV.
  • Belief that SIV could reduce the risk of influenza-induced complications (70.5%), hospitalisation (70.5%), and death (65.9%).
Low et al., 2017 [46]2016SingaporeQuantitative: cross-sectional survey3326 months–5 yearsUptake in the last flu season: 15%
Uptake in lifetime: 32%		Uptake in the last flu season
  • Associated factors: being recommended influenza vaccine by a child’s doctor, receiving influenza vaccine information from a private general practitioner, regularly receiving pre-travel influenza vaccine, parental willingness, being well informed about SIV knowledgeable about influenza with a score of 12 out of 15) and influenza vaccine with 88% of respondents were aware that there was a vaccine for influenza.
Ma et al., 2006 [47]2004USAQuantitative: cross-sectional survey2566–59 monthsUptake in the last flu season: 38%Uptake in the last flu season
  • Associated factors: recalling a physician’s recommendation, having a family member who had received the influenza vaccine, having a continuity clinic visit, and having a high-risk medical condition.
Nowalk et al., 2005 [48]2003USAQuantitative: cross-sectional survey4366–23 monthsUptake in the last flu season: 43.2%Uptake in the last flu season
  • Associated factors: perceived doctor’s recommendation, relatives and friends thinking that child should have a flu shot, the belief that a child with asthma should receive a flu shot, the belief that receiving an influenza shot is a smart idea, the belief that unvaccinated child will get the flu, and belief that flu shot prevents flu, worrying that child will get the flu from the flu shot, and the belief that the flu shot is more trouble than it is worth.
Nowalk et al., 2007 [21]2004USAQuantitative: cross-sectional survey2746–23 months.Uptake in the last flu season: 45%Uptake in the last flu season
  • Associated factors: doctor’s recommendation, receiving a reminder and belief that their young child should be vaccinated.
Price et al.,, 2022 [49]2020UKQualitative: semi-structured interview122–3 yearsNA
  • Facilitators included knowledge and awareness of IV, trust in the vaccine, access to vaccine information, physician recommendation, access to vaccination, perceived severity, social norms, the belief that vaccinating a child protects the wider family, and the belief that vaccinating a child is a social responsibility.
  • Barriers included a lack of knowledge about the flu, the belief that one’s child is not at risk from the flu, and the belief that catching the flu is inevitable for children, inconvenient appointments, lack of access due to a vaccine shortage, and lack of awareness about their child’s eligibility, and the fear of side-effects and frustration with or distrust of medical professionals.
Schuller et al., 2013 [50]2008USAQuantitative: cross-sectional survey25,25619–35 monthsUptake in the last flu season: 56.4%Uptake in the last flu season
  • Associated factors: primary caregiver being older, married, and more educated, a child with private insurance, younger children and first-born children, Black children were the least likely to have been immunised, an income above USD 75,000 per year, a small household size, and residence in the northeast were associated with an increased probability of immunisation, whereas living in the south was associated with decreased likelihood.
Schellenberg et al., 2023 [51]2018CanadaQuantitative: cross-sectional survey612524 monthsAcceptance: 87.7%
Hesitancy: 12.3%		Hesitancy
  • Female parents, the child had health issues or was too young, poor knowledge, and attitudes and beliefs increased likelihood of refusal.
Shinall et al., 2007 [52]2005USAQuantitative: cross-sectional survey1986–59 monthsUptake in the last flu season: 42%Uptake in the last flu season
  • More children who were 6 to 23 months than those who were 24 to 59 months of age were vaccinated.
  • Children with chronic medical conditions were more likely to be vaccinated than healthy children who were 24 to 59 months of age.
Thanee et al., 2021 [20]2019ThailandQuantitative: cross-sectional survey7006–36 monthsUptake in the last flu season: 9% Uptake in the last flu season
  • Caregivers of the vaccinated children were more likely to have higher education and to know of influenza illness.
  • Factors associated with children receiving influenza vaccination were identifying healthcare providers as a primary source of information about influenza illness for parents, parents’ strongly agreeing with the national recommendation for influenza vaccination in young children, using health insurance provided by the government or parent’s employer for children’s doctor visits, and the children’s history of receiving influenza vaccination in the 2017 season or earlier.
van Lier et al., 2017 [18]2012The NetherlandsQuantitative: cross-sectional survey4910–48 monthsAcceptance: 15%
Hesitancy: 85%		Acceptance
  • Main drivers of intention were the perceived importance of vaccination against the particular disease and the perception of whether or not the disease is severe enough to justify vaccination.
Wei et al., 2021 [17] China Quantitative: cross-sectional survey15640–59 monthsAcceptance: 56.8%
Hesitancy: 43.2%		Hesitancy
  • From rural areas, do not know the government recommendation for flu vaccination, do not know the flu vaccine is vaccinated annually, and family members, friends, and neighbours had a positive attitude toward flu vaccine were related factors of the guardians’ IVH
Williams et al., 2021 [53]2020USAQuantitative: cross-sectional survey2632 yearsUptake in the last flu season: 76.5%
Acceptance: 87%
Hesitancy: 13%		Hesitancy
  • Caccine-hesitant parents were more likely to be English-speaking, non-Latino race/ethnicity, non-publicly insured, and born in the United States.
Wu et al., 2015 [24]2011Hong KongQuantitative: cross-sectional survey54024–59 monthsUptake in lifetime: 58.9%Uptake in lifetime
  • Associated factors: family members’ SIV experience, perceived susceptibility to seasonal influenza, perceived benefits of IV, perceived barriers of IV, cue to action, and supportive subjective norm.
Wu et al., 2020 [25]2011Hong KongQuantitative: cross-sectional survey44024–59 monthsUptake in the last flu season: 30.22%
Uptake in lifetime: 63.2%
Acceptance: 49.3%
Hesitancy: 50.7%		Uptake in the last flu season
  • Facilitators included caregivers being female, parental positive attitude, norm, and behavioural intention.
Uptake in lifetime
  • Facilitators included positive attitudes (e.g., belief that IV is effective) and perceived norms, whilst barriers included negative attitudes.
Acceptance
  • Facilitators included visiting doctor before, positive attitudes, and perceived norms, whilst barriers included part-time/unemployed,
Wu et al., 2023 [19]2019ChinaQuantitative: cross-sectional survey14040–59 monthsUptake in the last flu season: 33.1%
Hesitancy: 40%
Hesitancy: 60%		Uptake in the last flu season
  • Associated factors included guardians’ gender being male, older age, lower education level, perceived benefit, knowing that government recommends influenza vaccination, that the influenza vaccine is recommended to be taken annually, those who reported that their communities promote influenza vaccination, with support of their family members, friends and neighbours, and health care workers, and hesitancy.
Hesitancy
  • Associated factors included relative knowledge and social influence.
Zhang et al., 2022 [15]2018ChinaQuantitative: cross-sectional survey47196–59 monthsUptake in the last flu season: 39.4% Uptake in the last flu season
  • Associated factors: older child age, living in Southern China were more likely to vaccinate.
Table 2. Summary of the uptake of seasonal influenza vaccination in the last flu season, uptake in lifetime, parental acceptance, and parental hesitancy from the included studies.
Table 2. Summary of the uptake of seasonal influenza vaccination in the last flu season, uptake in lifetime, parental acceptance, and parental hesitancy from the included studies.
Author, YearCountry/RegionSample SizeUptake in the Last Flu SeasonUptake in LifetimeAcceptanceHesitancyAssociated Factors
Bauer et al., 2021 [26]USA16544%-71%11%-
Brown et al.,
2011 [32]		USA307239.5%----
Bults et al., 2011 [33]The Netherlands312736%---Uptake in the last flu season: experienced feelings of doubt about the vaccination decision (−); information-seeking behaviour (−); social influence on their vaccination decision (+)
Chantler et al.,
2007 [34]		UK8311%----
Chen et al., 2011 [35]Taiwan277860.4%---Uptake in the last flu season: age of the caregiver (−); unemployed (+); living in rural areas (+); chronic disease (−); hospitalisation history (−); influenza histories of the child (+); perceived susceptibility (+)/perceived benefits of vaccinations (+); perceived barriers (−); cues to action (+)
Chen et al., 2015 [36]Taiwan130050%-73%27%Uptake in the last flu season: age of the caregiver (+); female gender (−); average household income (−); being mother compared to father(−); being grandfather compared to father (+); influenza vaccination of the children in the last year (+); children’s average frequency of cold per year (+); perceived benefits of the vaccination (+); cues to action (+); self-efficacy of childhood vaccination (+)
Choi et al.,
2017 [37]		Republic of Korea639--83.6%16.4%Uptake in the last flu season: household income (+); parental education level (+)
Daley et al., 2007 [28]USA83971%---Uptake in the past year: belief that IV is the social norm (+); perceived barriers (−)
Fisher et al., 2022 [14]Canada207--66%34%Acceptance: household income (+); perceived vaccine safety (+); perceived benefit (+); cues to action (+); perceived support from significant others (+)
Frawley et al., 2020 [16]Australia100252.9%---Uptake in the last flu season: being mother (−); having a health care card (+); know the influenza vaccine was free for the child (+); a recommendation from a health professional (+)
Ganczak et al., 2013 [38]Poland308-77.9%--Uptake in lifetime: age of the parent (+); socio-economic status (+); having only one child (+); health system factor, i.e., practice location (+); cost of a vaccine (−)
Gentile et al., 2015 [39]Argentina135073.1%---Uptake in the last flu season: perceived importance of IV (+)
Han et al., 2022 [40]China208143.6%---Uptake in the last flu season: parental education level (+); household income (−); confidence in the importance, safety, and effectiveness of influenza vaccine (+); knowing other caregivers were vaccinating their children (+); receiving positive influence from healthcare workers and family members (+); poor access, including conflicts between caregivers’ availability and vaccination service schedules and inconvenient transportation to the vaccination site (−)
He et al., 2015 [41]China 33547.7%-62.4%37.6%Uptake in the last flu season: household income (+); age of the child (+); social norm (+); perceived control (+); perceived vaccine safety (+)
Acceptance: household income (+); children with a history of taking SIV (+); perceived children’s health status (+); worry/anxious about their children influenza infection (+); perceived control (+); perceived vaccine safety (+); perceived benefit (+); social norm (+); perceived severity (+)
Hemingway et al., 2004 [42]USA32918%---Uptake in the last flu season: a physician’s recommendation (+); family members vaccinated (+)
Humiston et al., 2005 [43]USA153--78%22%Acceptance: perceived severity (+); perceived vaccine safety (+); perceived importance to vaccinate the child (+); parental education level (+)
Lai et al., 2022 [44]China6668--38.6%61.4%Hesitancy: perceiving importance to vaccinate the child (−); perceived vaccine safety (−); perceived vaccine efficacy (−); know children as a priority group (−); trusting vaccination advice from medical staff (−); perceived barriers (+); age of the child (−); the number of children in the family (−); caregivers’ age (−); parental education level (−); household income (+)
Lau et al., 2021 [45]Hong Kong540--68.9%31.1%Acceptance: being a mother (−); age of the child (−); positive influenza vaccination experience in family members (+); age of the parents (−); parental education level (+); perceived susceptibility (+); perceived benefit (+); perceived barrier (−); cue to action (+); subjective norm (+); having family members vaccinated (+)
Lau et al., 2013 [23]Hong Kong401-9%--Uptake in lifetime: a physician’s recommendations (+); parental perceptions of the side effects of IV (−)
Low et al., 2017 [46]Singapore33215%32%--Uptake in the last flu season: a physician’s recommendation (+); the child was vaccinated before (+); willingness to vaccinate (+); feeling well-informed about influenza vaccine (+); receiving influenza vaccine information from television (−)
Ma et al., 2006 [47]USA25638%---Uptake in the last flu season: a physician’s recommendation (+); having a family member vaccinated (+); having a continuity clinic visit (+); having a high-risk medical condition (+)
Nowalk et al., 2005 [48]USA43643.2%---Uptake in the last flu season: a physician’s recommendation (+); relatives and friends think that child should have flu shot (+); the belief that a child with asthma should receive a flu shot (+); the belief that receiving an influenza shot is a smart idea (+); the belief that unvaccinated child will get flu (+); belief that flu shot prevents flu (+); worrying that child will get the flu from flu shot (−); belief that the flu shot is more trouble than it is worth (−)
Nowalk et al., 2007 [21]USA27445%---Uptake in the last flu season: a physician’s recommendation (+); receiving a reminder (+); the parental belief that the child should be vaccinated (+)
Schuller et al., 2013 [50]USA25,25656.4%---Uptake in the last flu season: age of the parent (+); married (+); parental education level (+); a child with private insurance (+); age of the child (+); first-born child (+); ethnicity: black (+); household income level (+)
Schellenberg et al., 2023 [51]Canada6125--87.7%12.3%Hesitancy: female parents (−); child had health issues (−); age of the child (−); knowledge, attitudes and belief (−)
Shinall et al., 2007 [52]USA19842%---Uptake in the last flu season: age of the child (−); child with chronic medical conditions (+)
Thanee et al., 2021 [20]Thailand7009%---Uptake in the last flu season: parental education level (+); knowledge about influenza illness (+); healthcare providers as a primary source of information about influenza illness for parents (+); parents’ strongly agreeing with the national recommendation for influenza vaccination in young children (+); using health insurance provided by the government or parent’s employer for children’s doctor visits (+); the children’s history of receiving influenza vaccination (+)
van Lier et al., 2017 [18]The Netherlands491--15%85%Acceptance: perceived importance of vaccination against the particular disease (+); the perception of whether or not the disease is severe enough to justify vaccination (+)
Wei et al., 2021 [17]China 1564--56.8%43.2%Hesitancy: living in a rural area (+); do not know the government recommendation for flu vaccination (+); do not know the flu vaccine is vaccinated annually (+); family members, friends and neighbours had a positive attitude toward flu vaccine (−)
Williams et al., 2021 [53]USA26376.5%-87%13%Hesitancy: English-speaking (+); non-Latino race/ethnicity (+); non-publicly insured (+); born in the United States (+)
Wu et al., 2015 [24]Hong Kong540-58.9%--Uptake in lifetime: family members vaccinated (+); perceived susceptibility of seasonal influenza (+); perceived benefits of IV (+); perceived barriers of IV (−); cue to action (+); supportive subjective norm (+)
Wu et al., 2020 [25]Hong Kong44030.2%63.2%49.3%50.7%Uptake in the last flu season: caregivers being female (+); parental positive attitude (+); subjective norm (+); behavioral intention (+)
Uptake in a lifetime: positive attitudes (e.g., belief that IV is effective) (+); perceived norm (+); negative attitudes (−)
Acceptance: visiting doctor before (+); positive attitudes (+); perceived norm (+); parttime/unemployed (−); child’s uptake in the past year (+)
Wu et al., 2023 [19]China140433.1%-40.0%60.0%Uptake in the last flu season: caregiver being male (+); the age of the parent (+); parental education level (+); perceived benefit (+); knowing that government recommends influenza vaccination (+); knowing that the influenza vaccine is recommended to be taken annually (+); those who reported that their communities promote influenza vaccination (+); with support of their family members, friends and neighbours, and HCWs (+); hesitancy (−)
Hesitancy: relative knowledge (−); social influence (−)
Zhang et al., 2022 [15]China471939.4%---Uptake in the last flu season: age of the child (+); living in Southern China (+)
+ indicates positive association; − indicates negative association.
Table 3. Moderators of vaccine uptake, acceptance, and hesitancy rates of SIV (meta-regression and subgroup analyses).
Table 3. Moderators of vaccine uptake, acceptance, and hesitancy rates of SIV (meta-regression and subgroup analyses).
ModeratorNumber of
Studies		Proportion of
Outcome
(95% CI)		HeterogeneityModerator Effect
(Meta-Regression)
Univariate
I2 Withinp-ValueCoefficientp-Value
Uptake in the last flu season
Study year 0.010.87
2010 or before110.41 (0.30–0.53)99%<0.01
2011–201540.51 (0.33–0.68)99%<0.01
2016–201960.29 (0.16–0.47)99%<0.01
2020 or after20.61 (0.28–0.96)99%<0.01
Region 0.030.61
Asia90.34 (0.23–0.48)99%<0.01
Americas 110.50 (0.38–0.61)99%<0.01
Europe20.21 (0.06–0.55)95%<0.01
Oceania10.53 (0.50–0.56)--
Sample size 0.110.17
≤1000130.35 (0.23–0.49)99%<0.01
>1000100.48 (0.40–0.57)99%<0.01
Uptake in lifetime
Study year −0.020.91
2010 or before20.37 (0.02–0.95)100%<0.01
2011–201520.61 (0.57–0.65)47%0.17
2016–201910.32 (0.27–0.37)--
Region 0.190.28
Asia40.37 (0.14–0.68)99%<0.01
Americas 0---
Europe10.78 (0.73–0.82)--
Oceania0---
Sample size --
≤100050.46 (0.20–0.74)99%<0.01
>10000---
Parental acceptance
Study year 0.020.77
2010 or before10.78 (0.70–0.84)--
2011–201560.59 (0.36–0.78)99%<0.01
2016–201960.62 (0.44–0.77)100%<0.01
2020 or after10.87 (0.82–0.91)--
Region 0.190.04
Asia80.60 (0.48–0.71)99%<0.01
Americas 50.79 (0.70–0.87)96%<0.01
Europe10.15 (0.12–0.19)--
Oceania0---
Sample size −0.050.66
≤100090.66 (0.49–0.79)99%<0.01
>100050.62 (0.40–0.80)100%<0.01
Parental hesitancy
Study year −0.040.68
2010 or before10.22 (0.16–0.30)--
2011–201560.41 (0.22–0.64)93%<0.01
2016–201960.34 (0.17–0.55)100%<0.01
2020 or after10.13 (0.09–0.18)--
Region 0.220.02
Asia80.40 (0.29–0.52)99%<0.01
Americas50.17 (0.11–0.26)95%<0.01
Europe10.85 (0.81–0.88)--
Oceania0--
Sample size 0.070.57
≤100090.31 (0.18–0.50)99%<0.01
>100050.38 (0.20–0.60)100%<0.01
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Chan, P.S.-f.; Fang, Y.; Kawuki, J.; Chen, S.; Liang, X.; Mo, P.K.-h.; Wang, Z. Parental Acceptance, Parental Hesitancy, and Uptake of Seasonal Influenza Vaccination among Children Aged 6–59 Months: A Systematic Review and Meta-Analysis. Vaccines 2023, 11, 1360. https://doi.org/10.3390/vaccines11081360

AMA Style

Chan PS-f, Fang Y, Kawuki J, Chen S, Liang X, Mo PK-h, Wang Z. Parental Acceptance, Parental Hesitancy, and Uptake of Seasonal Influenza Vaccination among Children Aged 6–59 Months: A Systematic Review and Meta-Analysis. Vaccines. 2023; 11(8):1360. https://doi.org/10.3390/vaccines11081360

Chicago/Turabian Style

Chan, Paul Shing-fong, Yuan Fang, Joseph Kawuki, Siyu Chen, Xue Liang, Phoenix Kit-han Mo, and Zixin Wang. 2023. "Parental Acceptance, Parental Hesitancy, and Uptake of Seasonal Influenza Vaccination among Children Aged 6–59 Months: A Systematic Review and Meta-Analysis" Vaccines 11, no. 8: 1360. https://doi.org/10.3390/vaccines11081360

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop