Coverage and parental perceptions of influenza vaccination among parents of children aged 6 to 23 months in Hong Kong

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

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.

Intention and Attitude to Accept a Pertussis Cocooning Vaccination among Chinese Children's Guardians: A Cross-Sectional Survey

OBJECTIVE

to assess Chinese children's guardians' intentions and attitudes toward accepting a pertussis cocooning vaccination and its determinants.

METHODS

a self-administered questionnaire was designed based on a theoretical framework that originated mainly from the reasoned action approach. Associations between questionnaire variables and outcomes were assessed using univariate and multivariate analyses with odds ratios (OR), regression coefficients (β), and their 95% confidence intervals (CIs).

RESULTS

among 762 eligible participants, most (80.71%) reported a positive intention to accept a pertussis cocooning vaccination. The guardians' positive intention was related to the children's pertussis vaccination experience (OR = 2.483, 95% CI: 1.340-4.600). Guardians who had a positive attitude towards pertussis vaccination (OR = 1.554, 95% CI: 1.053-2.296), higher subjective norms (OR = 1.960, 95% CI: 1.371-2.802) and better perceived behavioral control (OR = 7.482, 95% CI: 4.829-11.591) stated a higher intention to receive a pertussis cocooning vaccination. The mean attitude score was 3.88 ± 0.863. Greater risk perception about pertussis (β = 0.390, 95% CI: 0.298-0.483), stronger obligation from moral norms (β = 0.355, 95% CI: 0.279-0.430), and good knowledge (β = 0.108, 95% CI: 0.070-0.146) were significantly related to positive attitude toward pertussis cocooning vaccination among guardians.

CONCLUSIONS

Chinese children's guardians held positive intentions and attitudes toward accepting a pertussis cocooning vaccination. The current findings described the determinants of such intention and attitude and provided knowledge based on improving guardians' intentions for policymakers if cocooning vaccinations or related immunization strategies are implemented in China in the future.

Factors associated with caregivers' hesitancy to vaccinate children against influenza: A cross-sectional survey in China

BACKGROUND

Seasonal influenza can cause serious harm to children under five years of age, while caregivers are still hesitant to vaccinate children against influenza. This study aimed to investigate caregivers' hesitancy regarding influenza vaccination and assess the associated factors.

METHODS

From August to October 2019, a cross-sectional survey was conducted in ten provinces in China. The questionnaire collected information about sociodemographic characteristics and caregivers' knowledge, perceptions and attitudes toward influenza vaccination. Caregivers were identified as not hesitating, hesitating or refusing to vaccinate children. Multinomial logistic regression was adopted to determine factors related to vaccine hesitancy based on the 3C model with three dimensions namely complacency, convenience and confidence.

RESULTS

A total of 6668 valid questionnaires were collected, among which 38.57% did not hesitate to vaccinate children against influenza, 56.03% were hesitant, and 5.40% refused. Multinomial logistic regression showed that caregivers perceiving high importance (AOR = 0.68 for hesitancy; 0.15 for refusal), safety (AOR = 0.42; 0.46) or efficacy (AOR = 0.73; 0.65) of influenza vaccination, knowing children as a priority group (AOR = 0.80; 0.48), and trusting vaccination advice from medical staff (AOR = 0.65; 0.51) had lower odds of hesitancy or refusal. Those considering price as a hindering factor had higher odds of hesitancy (AOR = 1.66) or refusal (AOR = 1.47), and those viewing time or distance as a hindering factor (AOR = 1.45) or having heard of vaccine-related negative information (AOR = 1.78) had higher odds of hesitancy. Sociodemographic characteristics were associated with vaccine hesitancy or refusal, and the associations varied for hesitators and refusers.

CONCLUSION

A large proportion of caregivers in China reported their hesitancy for influenza vaccination, and the associated factors of such hesitancy were complicated. Health professionals are recommended to spread relevant scientific knowledge and give vaccine-related suggestions to caregivers in doctor visits to promote caregivers' trust in influenza vaccination and therefore expand childhood vaccine coverage.

Hesitancy for influenza vaccine among healthcare workers and mothers of preschool children: A cross-sectional study in Zagazig, Egypt

BACKGROUND:

Vaccine hesitancy is a worldwide issue. To intensify our efforts to find a solution to this problem, we need to comprehend its magnitude and underlying causes. This study aimed to determine the prevalence of influenza vaccine hesitancy and the reasons for it among healthcare workers (HCWs) and mothers of preschool children attending Zagazig Maternal and Child Healthcare (MCH) Center, Sharqia Governorate.

MATERIALS AND METHODS:

A cross-sectional study was conducted in the Zagazig MCH Center involving 77 HCWs and 210 mothers of preschool children. Two validated questionnaires (one for HCWs and one for mothers of preschool children) were used to collect data on hesitancy to influenza vaccine. Data analysis perfomed using SPSS v 25.0. For quantitative variables, statistical significance was determined using t-test, whereas Chi-square test was employed for quantitative variables. Poisson regression model was used to determine the independent predictors of influenza vaccine hesitancy. P < 0.05 was used as a level of statistical significance.

RESULTS:

The prevalence of hesitancy to the influenza vaccine was 46.8% among HCWs and 54.3% among mothers of preschool children. Fear of side effects (42.9%) and doubt in the usefulness of the vaccine (42.1%) were the most frequent barriers. Hesitancy was significantly more prevalent in the negative-attitude HCWs (62.0%) than positive-attitude HCWs (18.5%). According to Poisson regression analysis, the age of the index child, the mothers' source of information, and the frequency of vaccination were the critical indicators of influenza vaccine hesitancy in the studied mothers.

CONCLUSION:

Influenza vaccine hesitancy among the studied sample is high (46.8% among HCWs, and 54.3% among mothers of preschool children). Periodic health education campaigns to increase awareness and change the negative attitude about the influenza vaccine are recommended.

Barriers and facilitators of childhood flu vaccination: the views of parents in North East England

Aim

The aim of this study was to complete a descriptive qualitative investigation of parents’ perceptions of the barriers and facilitators to flu vaccination for pre-school children.

Subject and method

Participants were recruited through various communication channels to maximize sample variation. Invitations to participate in the study were sent to members of the Newcastle University Parent Network and to parents who had participated in previous research conducted at Newcastle University. Twelve participants (six with vaccinated children, six whose children were not vaccinated) took part in a semi-structured interview via Zoom. Transcripts were coded using Nvivo 12 and data were thematically analyzed using the COM-B model of health behavior change.

Results

Participants whose children were not vaccinated against flu nonetheless generally held favourable views of vaccination and reported low concern about side-effects. Barriers involved a combination of internal and external factors, mainly a lack of convenient access to vaccination opportunities and flu vaccination being a low priority for busy parents.

Conclusion

Our findings suggest that socioeconomic status, which is known to influence other vaccination behaviors, may influence uptake of the flu vaccine in this population. Inconvenient vaccination opportunities and a lack of awareness of the need to vaccinate are major barriers to uptake for some parents. The finding that belief that flu vaccination is a civic responsibility is a new contribution to the literature.

The limited value of triage vital signs in predicting influenza infection in children aged 5 years and under in the emergency department: A single-center retrospective cross-sectional study

Diagnosing influenza in children aged 5 years and under can be challenging because of their difficulty in verbalizing symptoms. This study aimed to explore the value of the triage heart rate (HR), respiratory rate (RR), and temperature, either alone or when combined with individual symptoms and signs, in predicting influenza infection in this age group.This was a retrospective study covering 4 influenza seasons from 2017 to 2019 in an emergency department (ED) in Hong Kong. We recruited patients ≤5 years of age who had an reverse transcription polymerase chain reaction influenza test within 48 hours of ED presentation. The diagnostic performance of the triage HR, RR, and temperature was evaluated as dichotomized or categorized values with diagnostic odds ratios (DORs) calculated based on different age-appropriate thresholds. Linear discriminant analysis was performed to assess the combined discriminatory effect of age, HR, RR, and temperature as continuous variables.Of 322 patients (median age 26 months), 99 had influenza A and 13 had influenza B infection. For HR and RR dichotomized based on age-appropriate thresholds, the DORs ranged from 1.16 to 1.54 and 0.78 to 1.53, respectively. A triage temperature ≥39.0 °C had the highest DOR (3.32) among different degrees of elevation of temperature. The diagnostic criteria that were based on the presence of fever and cough and/or rhinitis symptoms had a higher DOR compared with the Centers for Disease Control and Prevention influenza-like illness criteria (4.42 vs 2.41). However, combining HR, RR, or temperature with such diagnostic criteria added very little to the diagnostic performance. The linear discriminant analysis model had a high specificity of 92.5%, but the sensitivity (18.3%) was too low for clinical use.Triage HR, RR, and temperature had limited value in the diagnosis of influenza in children ≤5 years of age in the ED. Fever and cough and/or rhinitis symptoms had a better diagnostic performance than the Centers for Disease Control and Prevention influenza-like illness criteria in predicting influenza in this age group.

Knowledge, attitude and practice of influenza vaccination among Lebanese parents: A cross-sectional survey from a developing country

Background

A growing number of parents refuse vaccination due to concerns about side effects. Influenza vaccine is no exception and remains one of the most controversial vaccines. Data regarding influenza vaccine uptake and parental knowledge, attitude and practice towards vaccination in the Lebanese population is lacking. The aim of this study was to assess the rate of vaccination refusal and potential associated factors among Lebanese parents of school-aged children, in general and with a focus on influenza vaccine.

Methods

A parent questionnaire was distributed in randomly selected 2 public and 2 private schools from the greater Beirut area during the school year 2017–2018. Questionnaires covered knowledge, attitude (including themes of efficacy, hesitancy and trust), and practice of vaccination in general and influenza vaccine in particular.

Results

The response rate was 76.5% (306/400). Overall, 29.4% parents reported vaccinating their children against influenza (62.2% in private and 37.7% in public schools). Younger age, paternal employment and higher household income were associated with higher vaccination rates (p = 0.01, 0.02 and <0.0001 respectively). Lack of vaccine recommendation by the physician was the most common reason for not taking it (47%). Parents who accepted influenza vaccination had higher scores in efficacy, hesitancy and trust and were more compliant with other vaccinations.

Conclusion

One third of parents of school aged children in the greater Beirut area vaccinate their children against influenza. This rate is likely lower in rural remote areas. Physician’s recommendation is the single most important predictor of such vaccination. Future studies tackling physicians’ attitude and practice are needed to help improve influenza vaccination rates in the Lebanese population.

Willingness and influential factors of parents of 3-6-year-old children to vaccinate their children with the COVID-19 vaccine in China

The impact of Coronavirus disease 2019 (COVID-19) on children aged 3-6 can be severe. Vaccination for COVID-19 is one of the most important primary preventative measures to reduce disease transmission. Parents are hesitant to vaccinate their children against COVID-19 because it was reported in the news that some adults have had adverse reactions to the vaccine. This study aims to investigate the willingness of Chinese parents of 3-6 year old children to vaccinate them with the COVID-19 vaccine and identify what factors influence their decisions. A survey was conducted using a two-stage stratified random sampling method from December 2020 to February 2021. We used univariate analysis and multivariate binary logistic analysis to explore potential factors that may determine the acceptance of the COVID-19 vaccine. Of the 468 parents who participated, 86.75% were willing to vaccinate their children with the COVID-19 vaccine. Parents who were female (OR = 2.591; 95% CI: 0.432-4.689), recognized their children in the high-risk category (OR = 2.494; 95% CI:1.244-5.002), often followed-up with COVID-19 vaccine-related information (OR = 9.065; 95% CI: 3.220-28.654), believed in the safety of the COVID-19 vaccine (OR = 3.068; 95% CI: 1.313-7.168), or thought the COVID-19 vaccine could prevent COVID-19 (OR = 13.750; 95% CI: 2.516-75.140) were more willing to vaccinate their children. To ease parents' hesitation about vaccines, the authority organization should release updated information on the safety and reliability of vaccines, target gender-specific health education for parents, and ask the media to report scientifically support information.

The vaccination rate among children with nonprogressive neurodevelopmental disorders in Bosnia and Herzegovina: A single centre experience

PURPOSE

The aim of this study is to determine the factors influencing the decrease of the vaccination rate among children with nonprogressive neurodevelopmental disorders in Bosnia and Herzegovina.

METHODS

This study included 149 parents of children with nonprogressive neurodevelopmental disorders. The children were rehabilitated at the University Clinical Hospital Mostar, from October 2017 to February 2019.

RESULTS

The vaccination rate of children with nonprogressive neurodevelopmental disorders was 34.9% (P < 0.001). Based on the results of this study, physicians were the most common source of information on vaccines and vaccination procedures for parents (70.3%), whereas the media was rarely used as the source of the information (33%) (P < 0.001). Of the cases, 58.4% accepted the opinion of the pediatrician (P = 0.041). The vaccination of children was postponed on the physician's recommendation in 87.6% of the cases (P < 0.001). Among healthcare professionals, neuropediatricians or neurophysiatrists (P = 0.023), together with pediatricians (P < 0.001), most often suggested postponing the vaccination.

CONCLUSION

Overall, this study showed that the majority of children with nonprogressive neurodevelopmental disorders were unvaccinated. The majority of the parents trusted the physicians' opinion on vaccination. Neuropediatricians and neurophysiatrists most often postponed the regular vaccination of children.

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

The World Health Organization recommends young children receive influenza vaccination (IV) annually. Stratified by children's previous IV status, this study investigated the associated factors of parental intention to let their children aged 24 to 59 months receive IV in the next 12 months in Hong Kong, China. We conducted a cross-sectional population-based telephone survey among 540 Chinese parents of children aged 24 to 59 months. The prevalence of parental intention regarding their child's IV was 68.9% and 19.8%, respectively, in the ever-vaccinated and never-vaccinated groups. Adjusted for background factors, perceived susceptibility (adjusted odds ratio [ORa] = 3.20, 95% confidence interval [CI] = 1.07-9.54), perceived benefit (ORa = 4.77, 95% CI = 2.52-9.05), perceived barrier (ORa = 0.38, 95% CI = 0.17-0.84), cue to action (ORa = 3.57, 95% CI = 1.88-6.78), subjective norm (ORa = 11.23, 95% CI = 6.17-20.46), and having family members vaccinated (ORa = 1.79, 95% CI = 1.09-2.96) were associated with parental intention for ever-vaccinated children's IV, while only perceived benefit (ORa = 8.85, 95% CI = 3.36-23.34) and subjective norm (ORa = 21.66, 95% CI = 9.25-50.71) were significant for never-vaccinated children. Our findings showed that the identified factors and applicability of the health belief model varied according to child's vaccination status. Health promotion should consider segmentation principles. Besides modifying related cognitions like perceived benefit and barrier (only for the ever-vaccinated group), such programs should improve cue to action involving health professionals and family members and create supportive subjective norms.

A systematic review of studies that measure parental vaccine attitudes and beliefs in childhood vaccination

Background

Acceptance of vaccines is an important predictor of vaccine uptake. This has public health implications as those who are not vaccinated are at a higher risk of infection from vaccine preventable diseases. We aimed to examine how parental attitudes and beliefs towards childhood vaccination were measured in questionnaires through a systematic review of the literature.

Methods

We systematically reviewed the literature to identify primary research studies using tools to measure vaccine attitudes and beliefs, published between January 2012 and May 2018. Studies were included if they involved a quantitative survey of the attitudes and beliefs of parents about vaccinations recommended for children. We undertook a synthesis of the results with a focus on evaluating the tools used to measure hesitancy.

Results

A total of 116 studies met the inclusion criteria, 99 used a cross sectional study design, 5 used a case control study design, 4 used a pre-post study design and 8 used mixed methods study designs. Sample sizes of included studies ranged from 49 to 12,259. The most commonly used tool was the Parent Attitudes about Childhood Vaccines (PACV) Survey (n = 7). The most common theoretical framework used was the Health Belief Model (n = 25). Questions eliciting vaccination attitudes and beliefs varied widely.

Conclusions

There was heterogeneity in the types of questionnaires used in studies investigating attitudes and beliefs about vaccination in parents. Methods to measure parental attitudes and beliefs about vaccination could be improved with validated and standardised yet flexible instruments. The use of a standard set of questions should be encouraged in this area of study.

A longitudinal study using parental cognitions based on the theory of planned behavior to predict childhood influenza vaccination

BACKGROUND

The World Health Organization recommends young children aged 6-59 months receive influenza vaccination (IV) annually. This study investigated the IV incidence in a 12-month follow-up period among 24-59 month-old children and identified its predictors based on the theory of planned behavior (TPB).

METHODS

A population-based random telephone survey was conducted at baseline (March-June 2011) among Chinese parents of 24-59 month-old children in Hong Kong, China, and a follow-up survey was conducted 12 months afterwards (N=440).

RESULTS

The IV prevalence was 63.2% at follow-up (3% increased from baseline). The IV incidence during the follow-up period for all sampled, ever-vaccinated, and never-vaccinated children was 35.6, 58.5, and 7.7 per 100 person-years, respectively. Stratified analyses of logistic regression were performed for the ever-vaccinated and never-vaccinated children. After adjusting for significant socio-demographic variable(s), parental positive attitude, norm, and behavioral intention were significant predictors of IV at follow-up among ever-vaccinated children, while intention was the only significant predictor among never-vaccinated children.

CONCLUSIONS

Most of the IVs received during the follow-up period were re-vaccinations rather than first-time vaccinations. Efforts should target never-vaccinated children's parents, who reported low incidence and intention. TPB also worked less well among never-vaccinated children, and thus research for other predictors of never-vaccinated children's first-time vaccination are warranted. Promotion programs should consider segmentation by children's prior vaccination status.

Using classification and regression tree analysis to explore parental influenza vaccine decisions

BACKGROUND AND OBJECTIVES

Influenza poses a public health threat for children and adults. The CDC recommends annual influenza vaccination for children <18 years, yet vaccine uptake remains low for children (57.9%) and adults (37.1%). Given that parental decision-making is key in childhood vaccine uptake, there is a critical need to understand vaccine hesitancy among parents who decide not to vaccinate their children. This study aims to explore predictors of children's influenza vaccine status given parental vaccination status and examine the factors that contribute to concordance or discordance between parental and children's vaccine uptake.

METHODS

Classification and regression tree (CART) analyses were used to identify drivers of parental decisions to vaccinate their children against influenza. Hierarchy and interactions of these variables in predicting children's vaccination status were explored.

RESULTS

From a nationally representative sample of non-Hispanic Black and White parents who completed an online survey (n = 328), the main factors influencing parents' decisions to vaccinate their children were vaccine behavior following physician recommendation, knowledge of influenza recommendations for children, influenza vaccine confidence and disease risk. Among unvaccinated parents, the greatest concordance was observed among parents who usually do not get vaccinated following physician recommendation and had lower knowledge of recommendations for influenza vaccination for children. The greatest discordance was observed among unvaccinated parents who had lower hesitancy about recommended vaccines.

CONCLUSIONS

Understanding drivers of parental decisions to vaccinate themselves and their children can provide insights on health communication and provider approaches to increase influenza vaccine coverage and prevent influenza related mortality.

Effectiveness of Partial and Full Influenza Vaccination Among Children Aged <9 Years in Hong Kong, 2011-2019

BACKGROUND

Two doses of influenza vaccination are recommended for previously unvaccinated children aged <9 years, and receipt of 1 dose is sometimes termed "partial vaccination." We assessed the effectiveness of partial and full influenza vaccination in preventing influenza-associated hospitalization among children in Hong Kong.

METHODS

Using the test-negative design we enrolled 23 187 children aged <9 years admitted to hospitals with acute respiratory illness from September 2011 through March 2019. Vaccination and influenza status were recorded. Fully vaccinated children included those vaccinated with 2 doses or, if previously vaccinated, those vaccinated with 1 dose. Partially vaccinated children included those who should have received 2 doses but only received 1 dose. We estimated vaccine effectiveness (VE) by using conditional logistic regression models matched on epidemiological week.

RESULTS

Overall VE estimates among fully and partially vaccinated children were 73% (95% confidence interval, 69%-77%) and 31% (95% confidence interval, 8%-48%), respectively. A consistently higher VE was observed in children fully vaccinated against each influenza virus type/subtype. The effectiveness of partial vaccination did not vary by age group.

CONCLUSIONS

Partial vaccination was significantly less effective than full vaccination. Our study supports the current recommendation of 2 doses of influenza vaccination in previously unvaccinated children <9 years of age.

Determinants of Parental Intentions to Vaccinate Kindergarten Children Against Seasonal Influenza in Xiamen, China

Seasonal influenza epidemics occur almost every year, and children under 6 years of age constitute one of the most susceptible groups. While free vaccinations are offered to preschool children in some large cities in China, Xiamen lacks a free vaccination policy and other effective policies aimed at increasing parents' acceptance of the vaccine. Using the health belief model (HBM), we sought to: (1) investigate the determinants of parents' intentions to vaccinate their kindergarten children against seasonal influenza if the free policy were implemented, and (2) explore the possible interaction effects between "cues to action" and "perceived susceptibility" and/or "perceived severity." A total of 1350 parents with kindergarten children were selected by stratified random sampling from half the population in Xiamen, of whom 1211 responded effectively to our survey. Scobit models with testing for interactions among the key concepts of the HBM were used to investigate factors associated with parents' intentions to vaccinate their children. In total, 85.1% of 1211 parents reported that they were willing to vaccinate their children if free influenza vaccinations were offered, although only 37 children (3.1%) had received influenza vaccination in the previous year, and 261 (21.6%) had been vaccinated since birth. Parents' perceived susceptibility (AOR = 1.77), perceived benefits (AOR = 3.12), perceived barriers (AOR = 0.38) and cues to action (AOR = 3.54) in terms of childhood vaccination against influenza were significantly associated with their vaccination intentions. The only observed interaction effect was between perceived susceptibility and cues to action (AOR = 1.57), which had additive effects on strengthening parental intentions to vaccinate their children. Our findings can be used as a basis for formulating government strategies aimed at improving influenza vaccination coverage among children in kindergarten and guiding culturally informed primary prevention efforts among their parents.

Influenza vaccine coverage and predictive factors associated with influenza vaccine uptake among pediatric patients

BACKGROUND

Despite recommendations from health care authorities, reports of severe influenza occur yearly among unvaccinated infants and children.

OBJECTIVES

This study investigated influenza vaccine coverage and predictive factors for vaccination status among pediatric patients during the 2016-2017 winter influenza season.

METHODS

A cross-sectional survey was conducted among parents of our study population identified through a major pediatric outpatient clinic in Hong Kong. Parents with a child aged 6 months to 17 years were invited to complete a questionnaire that assessed the current influenza vaccine status of the child and the parents' understanding and beliefs regarding influenza and its vaccine. A backward logistic regression was conducted to determine predictive factors and adjusted odds ratios associated with influenza vaccine uptake.

RESULTS

Our study included 348 parents and 405 pediatric patients. Of these, 142 pediatric patients (35.1%) received full vaccination. Predictive factors associated with the child's positive influenza vaccine status include a "very good" parental understanding of influenza and its vaccine (adjusted odds ratio, 6.7; 95% confidence interval,  2.1-21.5), a child with chronic medical condition and a "high" cue to action (adjusted odds ratio, 5.7; 95% confidence interval, 2.8-11.6), and a "high" perceived susceptibility toward influenza (adjusted odds ratio, 4.8; 95% confidence interval, 2.1-10.8).

CONCLUSIONS

This study reflects the low influenza vaccine coverage among pediatric patients. Interventions focusing on parental knowledge and understanding of influenza and its vaccine may improve future vaccine uptake among the pediatric population.

Low coverage of influenza vaccination among Chinese children aged 12-23 months: Prevalence and associated factors

This study aimed to investigate prevalence and associated factors of influenza vaccination (IV) among children aged 12-23 months. Our cross-sectional survey interviewed 489 parents of children aged 12-23 months anonymously at twelve maternal and child health centers in Hong Kong. Results showed that only 11.5% of the children had ever received IV (64.3% being subsidized). Adjusted for the child's age, significant factors of the children's IV included parental knowledge about governmental policy/recommendation (Adjusted odds ratio [AOR] = 2.64, 95%CI = 1.09,6.40), knowledge about annual IV requirement (AOR = 2.30, 95%CI = 1.21,4.38), perceived safety-related barrier (AOR≥0.14, 95%CI = 0.06,0.33), cue to action (AOR = 7.79, 95%CI = 3.45,17.58), and subjective norm (AOR = 4.59, 95%CI = 2.34,9.00). IV prevalence of children aged 12-23 months remained low despite a subsidization scheme. The higher IV prevalence of older children reported by other studies suggested that parents postponed action. Promotion campaigns should shift emphases from cost reduction and mass media approaches to dissemination of knowledge about IV policy and safety, enhancement of health professionals' advice, and creation of supportive subjective norm.

Increasing influenza vaccine uptake in children: A randomised controlled trial

BACKGROUND

Influenza vaccine is not included in the Hong Kong Government's universal Childhood Immunisation Programme but eligible children can receive subsidised vaccine through the private sector using the Vaccination Subsidy Scheme (VSS). This study examined whether a simple intervention package can increase influenza vaccine uptake in Hong Kong children.

METHODS

Two study samples were enrolled: families of children who had participated in a previous knowledge, attitudes and practices study; and mother-infant pairs recruited from postnatal wards. Control groups received publicly available leaflets about VSS. Intervention groups additionally received: (1) a concise information sheet about influenza and its vaccine; (2) semi-completed forms to utilise the subsidy; (3) contacts of VSS clinics that did not charge above the subsidy; and (4) text message reminders for vaccination. Enrolled mothers were contacted when children were approximately 1 and 2 years old to determine influenza vaccination status of the families and their plan to vaccinate their children. Mothers' attitudes towards influenza vaccine were assessed at enrolment and at the end of the study.

RESULTS

A total of 833 eligible mother-infant pairs were enrolled from the two samples. The intervention package improved influenza vaccine uptake by 22% at one year and 25% at two years of age. Maternal influenza vaccine uptake in intervention group was higher during this two-year period in those who had never been previously vaccinated. Mothers' self-efficacy regarding the use of influenza vaccine in her child i.e. belief and confidence in her own ability to make a good decision, was also improved with the intervention.

CONCLUSIONS

A four-component intervention package could improve influenza vaccine uptake in Hong Kong children and their mothers during the first two years of life and depending on vaccine effectiveness could potentially reduce influenza-associated hospital admissions in children below 2 years old by 13-24%.

Parental perceptions of childhood seasonal influenza vaccination in Singapore: A cross-sectional survey

PURPOSE

Seasonal influenza vaccination is recommended in children aged 6-59months, but little is known about child vaccination coverage and determinants in Asian settings. We report the results of a survey of knowledge, attitudes, practices, and determinants of child influenza vaccination in Singapore.

METHODS

In December 2015-March 2016, we conducted a survey of 332 parents of children aged 6months to 5years attending pre-schools. We assessed child influenza vaccine coverage and parental knowledge, attitudes, and practices of child influenza vaccination. We used multivariable regression and structural equation models to identify factors associated with child influenza vaccination.

RESULTS

Knowledge about influenza, perceived benefit of vaccination, and willingness to vaccinate were high. However, only 32% of children had ever received influenza vaccine, and only 15% in the past year. Factors independently associated with child influenza vaccination included: being recommended influenza vaccine by a child's doctor (prevalence ratio (PR)=2.47, 95% CI: 1.75-3.48); receiving influenza vaccine information from a private general practitioner (PR=1.47, 95% CI: 1.05-2.04); regularly receiving pre-travel influenza vaccine (PR=1.64, 95% CI: 1.19-2.25); higher willingness to vaccinate (PR=1.58, 95% CI:1.24-2.04 per unit increase in willingness score); and feeling well-informed about influenza vaccine (PR=1.44, 95% CI: 1.04-1.99). Parents who obtained influenza vaccine information from television were less likely to have vaccinated their child (PR=0.44, 95% CI: 0.23-0.85). Path analysis indicated that being recommended vaccination by a child's doctor increased willingness to vaccinate and self-efficacy (feeling well-informed about influenza vaccine). Median willingness-to-pay for a dose of influenza vaccine was SGD30 (interquartile range: SGD20-SGD50), and was higher in parents of vaccinated compared with unvaccinated children (SGD45vs SGD30, p=0.0012).

CONCLUSION

Knowledge and willingness to vaccinate was high in this parent population, but influenza vaccine uptake in children was low. Encouraging medical professionals to recommend vaccination of eligible children is key to improving uptake.

An integrative review on parents' perceptions of their children's vaccinations

An integrative literature review was conducted for studies published between January 2005 and January 2016 to obtain evidence on parents' experiences and perceptions of vaccinations. Considering the mandatory nature of vaccinations in many countries and the influences of parental experiences on the outcome of vaccinations, it is essential to understand the experiences and needs of parents regarding their children's vaccinations. CINAHL, PsycINFO, PubMed, Scopus and ScienceDirect were searched for data. In this review, 20 studies (10 quantitative and 10 qualitative) that related to parental perceptions regarding their child's vaccination were included. The parents had varied views on vaccination and they had many vaccination-related concerns and difficulties. Different factors influenced their vaccination decisions and they had varied support needs. This review found that exploring parental perceptions regarding their child's vaccination in terms of the attitudes and experiences of parents, how these affect vaccination decisions as well as the needs of parents regarding their children's vaccinations is important in multicultural societies.

Factors Determining the Uptake of Influenza Vaccination Among Children With Chronic Conditions

BACKGROUND

Studies report that the influenza vaccination uptake rate among children with chronic conditions is alarmingly low. In Hong Kong, there has been no study examining parental decision making about influenza vaccination for children with chronic conditions, thereby limiting the knowledge base to inform the development of specific strategies to improve influenza vaccination rates. The aim of this study was to identify factors determining the uptake of influenza vaccination among children with chronic conditions.

METHODS

We conducted a cross-sectional survey of 623 parents with children having a chronic condition recruited from pediatric wards and specialty outpatient departments of 2 acute hospitals. A questionnaire developed by Daley et al based on the Health Belief Model was used to examine parents' beliefs and attitudes toward influenza and vaccination.

RESULTS

The parents' and their children's mean age were 40.1 ± 8.1 and 8.0 ± 4.5 years, respectively. Among the children, the most prevalent chronic conditions were asthma, chronic respiratory disease and cardiomyopathy. One-third (33%) of the children had influenza vaccination in the past 12 months. More than one-third (39%) of parents intended to vaccinate their children against influenza in the coming influenza season. A multivariable logistic regression analysis revealed that all subscale scores except perceived severity and knowledge about influenza were independently significantly associated with uptake.

CONCLUSIONS

The findings indicate that parents of children with chronic conditions lack awareness of the risks of influenza and have insufficient understanding about the benefits of vaccination. These findings could inform the development of interventions to promote vaccination uptake among children with chronic conditions.

Factors associated with parental acceptance of seasonal influenza vaccination for their children - A telephone survey in the adult population in Germany

INTRODUCTION

Influenza vaccination of children with underlying chronic diseases is currently recommended in Germany, but targeting all children constitutes an alternative approach to control seasonal influenza. To inform the modelling of vaccination impact and possible communication activities, we aimed to assess among parents the acceptance of universal childhood vaccination against seasonal influenza and possible modifiers.

METHODS

We conducted a telephone survey in households in Germany using random digit dialing. We interviewed parents with children aged <18 years by constructing three hypothetical scenarios in subsequent order: (1) hearing about the influenza vaccination recommendation through the media, (2) the vaccine being recommended by a physician, and (3) being informed about the availability of the vaccine as a nasal spray. We calculated the proportion of parents who would immunize their child and used univariable and multivariable logistic regression to identify factors associated with influenza vaccination intention.

RESULTS

Response was between 22 and 46%. Of 518 participants, 74% were female, mean age was 41.3 years. Participants had on average 1.6 children with a mean age of 8.9 years. In scenario 1, 52% of parents would immunize their child, compared to 64% in scenario 2 (p<0.01) and to 45% in scenario 3 (p=0.20). Factors independently associated with vaccination acceptance in scenario 1 were previous influenza vaccination of the child or parent (adjusted odds ratio [aOR] 4.5 and 8.6, respectively), perceived severity of influenza (aOR=5.1) and living in eastern Germany (aOR=2.4).

CONCLUSION

If seasonal influenza vaccination was recommended for all children, more than half of the parents would potentially agree to immunize their child. Involving physicians in future information campaigns is essential to achieve high uptake. As intranasal vaccine administration is non-invasive and easily done, it remains unclear why scenario 3 was associated with low acceptance among parents, and the underlying reasons should be further explored.

Barriers of Influenza Vaccination Intention and Behavior - A Systematic Review of Influenza Vaccine Hesitancy, 2005 - 2016

BACKGROUND

Influenza vaccine hesitancy is a significant threat to global efforts to reduce the burden of seasonal and pandemic influenza. Potential barriers of influenza vaccination need to be identified to inform interventions to raise awareness, influenza vaccine acceptance and uptake.

OBJECTIVE

This review aims to (1) identify relevant studies and extract individual barriers of seasonal and pandemic influenza vaccination for risk groups and the general public; and (2) map knowledge gaps in understanding influenza vaccine hesitancy to derive directions for further research and inform interventions in this area.

METHODS

Thirteen databases covering the areas of Medicine, Bioscience, Psychology, Sociology and Public Health were searched for peer-reviewed articles published between the years 2005 and 2016. Following the PRISMA approach, 470 articles were selected and analyzed for significant barriers to influenza vaccine uptake or intention. The barriers for different risk groups and flu types were clustered according to a conceptual framework based on the Theory of Planned Behavior and discussed using the 4C model of reasons for non-vaccination.

RESULTS

Most studies were conducted in the American and European region. Health care personnel (HCP) and the general public were the most studied populations, while parental decisions for children at high risk were under-represented. This study also identifies understudied concepts. A lack of confidence, inconvenience, calculation and complacency were identified to different extents as barriers to influenza vaccine uptake in risk groups.

CONCLUSION

Many different psychological, contextual, sociodemographic and physical barriers that are specific to certain risk groups were identified. While most sociodemographic and physical variables may be significantly related to influenza vaccine hesitancy, they cannot be used to explain its emergence or intensity. Psychological determinants were meaningfully related to uptake and should therefore be measured in a valid and comparable way. A compendium of measurements for future use is suggested as supporting information.

Potent protection against H5N1 and H7N9 influenza via childhood hemagglutinin imprinting

Two zoonotic influenza A viruses (IAV) of global concern, H5N1 and H7N9, exhibit unexplained differences in age distribution of human cases. Using data from all known human cases of these viruses, we show that an individual's first IAV infection confers lifelong protection against severe disease from novel hemagglutinin (HA) subtypes in the same phylogenetic group. Statistical modeling shows that protective HA imprinting is the crucial explanatory factor, and it provides 75% protection against severe infection and 80% protection against death for both H5N1 and H7N9. Our results enable us to predict age distributions of severe disease for future pandemics and demonstrate that a novel strain's pandemic potential increases yearly when a group-mismatched HA subtype dominates seasonal influenza circulation. These findings open new frontiers for rational pandemic risk assessment.

The Health Literacy of Hong Kong Chinese Parents with Preschool Children in Seasonal Influenza Prevention: A Multiple Case Study at Household Level

BACKGROUND

Health literacy influences individual and family health behaviour, health services use, and ultimately health outcomes and health care costs. In Hong Kong, people are at risk of seasonal influenza infection twice a year for three-month periods. Seasonal influenza is significantly associated with an increased number of hospitalized children. There is no research that provides an understanding of parents' health knowledge and their access to health information concerning seasonal influenza, nor their capacity to effectively manage influenza episodes in household. Such knowledge provides valuable insight into enhancing parents' health literacy to effectively communicate health messages to their children and support healthy behaviour development through role modelling.

METHODS

A multiple case study was employed to gain a multifaceted understanding of parents' health literacy regarding seasonal influenza prevention. Purposive intensity sampling was adopted to recruit twenty Hong Kong Chinese parents with a healthy three-to-five year old preschool child from three kindergartens. A content analysis was employed to categorize, tabulate and combine data to address the propositions of the study. Comprehensive comparisons were made across cases to reveal the commonalities and differences.

RESULTS

Four major themes were identified: inadequate parents' knowledge and reported skills and practices related to seasonal influenza prevention; parental knowledge seeking and exchange practices through social connection; parents' approaches to health information and limited enabling environments including shortage of health resources and uneven resource allocation for health promotion.

CONCLUSIONS

The findings recommend that community health professionals can play a critical role in increasing parents' functional, interactive and critical health literacy; important elements when planning and implementing seasonal influenza health promotion.

Prevalence and associated factors of seasonal influenza vaccination among 24- to 59-month-old children in Hong Kong

BACKGROUND

Influenza results in severe complications among 24- to 59-month-old children, who are recommended by the WHO to take up influenza vaccination (IV) annually. Health promotion is warranted. Yet, there is a dearth of studies on IV prevalence and associated factors in this age group.

METHODS

A random population-based telephone survey interviewed 540 parents of Chinese children aged 24-59 months in Hong Kong during March through June, 2011. Constructs of the Health Belief Model (HBM) and subjective norm formed basis for assessing parental perceptions on influenza and IV. For data analysis, adjusted, and stepwise multiple logistic regression models were fit.

RESULTS

The prevalence of having taken up at least one dose and two doses of IV among children aged 24-59 months was 58.9 and 42.4%, respectively. Significant associated factors included family members' IV experience (ORu=5.37, 95% CI: 3.48, 8.29), variables related to the HBM constructs (except perceived severity) [perceived susceptibility of seasonal influenza (ORu=2.03, 95% CI: 1.39, 2.95), perceived benefits of IV (ORu=3.11, 95% CI: 2.05, 4.71), perceived barriers (ORu=0.49, 95% CI: 0.25, 0.96) of IV, and cue to action (ORu=4.79, 95% CI: 2.87, 7.99)], supportive subjective norm (ORu=4.26, 95% CI: 2.91, 6.25), and level of fear felt during the H1N1 pandemic (ORu=1.97, 95% CI: 1.01, 3.87). Adjusted for the child's age, the same significant factors were found. Exposure to related media messages was statistically non-significant.

CONCLUSION

The reported IV prevalence was higher than that of 24- to 59-month-old children reported in other studies. There is room for improvement through health promotion, which should modify parental cognitions related to HBM (except perceived severity and self-efficacy) and involve family members to create subjective norm. Media campaigns may be inadequate for promotion of IV; use of the setting approach may be considered.

Burden of influenza infection in hospitalised children below 6 months of age and above in Hong Kong from 2005 to 2011

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Incidence of hospital admission with a diagnosis of influenza was highest in infants aged 2 month to <6 months (1762 per 100,000 person-years).

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Incidence of hospital admission with a diagnosis of influenza for children <18 y.o. was highest when A(H1N1)pdm09 was circulating in Apr 09/Mar 10.

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Laboratory confirmed influenza at one sentinel site was obtained in 1.6% of admissions aged 6 days to <6 months and in 5.2% aged 6 days to <18 years.

The World Health Organization recommends vaccination of pregnant women for seasonal influenza that can also protect infants aged below 6 months. We estimated incidence and disease burden of influenza in hospitalised children below and above 6 months of age in Hong Kong during a 6 year period. Discharge diagnoses for all admissions to public Hong Kong Hospital Authority hospitals, recorded in a central computerised database (Clinical Management System, CMS), were analysed for the period April 2005 to March 2011. Incidence estimates of influenza disease by age group were derived from CMS ICD codes 487–487.99. Laboratory-confirmed influenza infections from a single surveillance hospital were then linked to the CMS entries to assess possible over- and under-diagnosis of influenza based on CMS codes alone. Influenza was recorded as any primary or any secondary diagnosis in 1.3% (1158/86,582) of infants aged above 6 days to below 6 months and 4.3% (20,230/471,482) of children above 6 days to below 18 years. The unadjusted incidence rates per 100,000 person-years based on any CMS diagnosis of influenza in all admission to Hong Kong public hospitals were 627 in the below 2 months of age group and 1762 in the 2 month to below 6 month group. Incidence of hospitalisation for influenza in children was highest from 2 months to below 6 months. In the absence of vaccines for children below 6 months of age, effective vaccination of pregnant women may have a significant impact on reducing influenza hospitalisations in this age group.