The Impact and Vaccination Coverage of Seasonal Influenza among Children Aged 6-59 Months in China in 2017-2018: An Internet Panel Survey

Effectiveness of influenza vaccine among the population in Chongqing, China, 2018-2022: A test negative design-based evaluation

Influenza vaccination is the most cost-effective strategy for influenza prevention. Influenza vaccines have been found to be effective against symptomatic and medically attended outpatient influenza illnesses. However, there is currently a lack of data regarding the effectiveness of inactivated influenza vaccines in Chongqing, China. We conducted a prospective observational test-negative design study. Outpatient and emergency cases presenting with influenza-like illnesses (ILI) and available influenza reverse transcription polymerase chain reaction (RT-PCR) were selected and classified as cases (positive influenza RT-PCR) or controls (negative influenza RT-PCR). A total of 7,307 cases of influenza and 7,905 control subjects were included in this study. The overall adjusted influenza vaccine effectiveness (IVE) was 44.4% (95% confidence interval (CI): 32.5-54.2%). In the age groups of less than 6 years old, 6-18 years old, and 19-59 years old, the adjusted IVE were 32.2% (95% CI: 10.0-48.9%), 48.2% (95% CI: 30.6-61.4%), and 72.0% (95% CI: 43.6-86.1%). The adjusted IVE for H1N1, H3N2 and B (Victoria) were 71.1% (95% CI: 55.4-81.3%), 36.1% (95% CI: 14.6-52.2%) and 33.7% (95% CI: 14.6-48.5%). Influenza vaccination was effective in Chongqing from 2018 to 2022. Evaluating IVE in this area is feasible and should be conducted annually in the future.

Attitudes, motivators, and barriers toward influenza vaccination for children: a study from a conflict-ridden country

BACKGROUND

Despite the increased recommendations for influenza vaccination, particularly among high-risk groups such as young children, Yemen lacks an influenza vaccination program, and the influenza vaccine is not included in the national immunization regime. This is exacerbated by the country's fragile infrastructure, as well as the devastating consequences of the ongoing conflict, which include child undernutrition and strained healthcare resources. Thus, the objective of the current study is to assess the public attitudes and perceptions toward vaccinating children against influenza in Yemen.

METHODS

A cross-sectional study was conducted by distributing a validated survey questionnaire to potential participants using convenience sampling. Descriptive statistics were used to summarize sociodemographic data, knowledge of influenza vaccines, and attitudes and perceptions regarding vaccinating children against influenza. Logistic regression analysis was employed to identify associations between independent variables and the acceptance of vaccines for children.

RESULTS

A total of 853 eligible individuals, parents and non-parents, successfully completed the survey. The uptake of the influenza vaccine among the participants was notably low as the majority (69.2%) had not previously received the vaccine, although the majority expressed a willingness to get vaccinated in the future (59.4%). The majority (68.5%) were willing to vaccinate children. The largest percentage of the participants who expressed hesitancy toward children's vaccination cited multiple reasons to reject the vaccine (39.7%), with concerns regarding the safety of the vaccine being the predominant barrier to its acceptance for children (29.6%). On the other hand, motivating factors for vaccinating children included the validation of the vaccine's safety and efficacy, endorsement of the vaccine by the government and physicians, integration of the vaccine into the national immunization program, and the provision of the vaccine free of charge and through schools. Significant predictors for vaccine acceptance in children included male gender, knowledge of the protective effect of the influenza vaccine, previous receipt of the vaccine, and a willingness to receive the vaccine in the future.

CONCLUSIONS

The study highlights the need for educational health campaigns to raise awareness and remove misconceptions regarding influenza and the role, benefits, and availability of its vaccine. These findings can serve as a robust foundation for the future design and implementation of an influenza vaccination program for children in Yemen.

Disparity in spectrum of infectious diseases between in-school and out-of-school children, adolescents, and youths in China: findings from a successive national surveillance from 2013 to 2021

Background

An accelerated epidemiological transition, economic development and urbanization have brought rapid reductions but a potential disparity in infectious diseases burdens in-school and out-of-school children, adolescents, and youths in China. This paper assesses the disparity in spectrum of infectious diseases between two groups, and described disparity's variation by age, year and province, and determined the priority diseases.

Methods

A total of 7,912,274 new incident cases (6,159,021 in school and 1,753,253 out of school) aged 6-21 years across 43 notifiable infectious diseases have been collected based on China's Notifiable Infectious Disease Surveillance System from 2013 to 2021. All infectious diseases are categorized into seven categories: vaccine preventable, bacteria, gastrointestinal and enterovirus, sexually transmitted and bloodborne, vectorborne, zoonotic, and quarantinable diseases. We used the index of incidence rate ratio (IRR) of by specific disease, category, year, and age to assess the disparity between those out-of-school and in-school, and determine their separate priority diseases.

Findings

From 2013 to 2021, a small disparity of notifiable infectious diseases existed with higher average yearly incidence for out-of-school children, adolescents, and youth than that in-school (327.601 v.s. 319.677 per 100,000, IRR = 1.025, 95%CI: 1.023-1.027, standardized IRR = 1.169, 95%CI: 1.155-1.183), and it gradually narrowed by surveillance years with IRR from 1.351 in 2013 to 1.015 in 2021 due to large decreased disparity in compulsory education stage group. Such disparity was mainly driven by sexually transmitted and bloodborne diseases, bacteria diseases, vectorborne diseases, quarantinable diseases and zoonotic diseases. However, vaccine preventable diseases, gastrointestinal and enterovirus diseases showed higher incidence of infectious diseases for those in-school than that out-of-school, particularly for seasonal influenza, mumps and hand-foot-and-mouth disease. Meanwhile, such disparity is obvious in most of ages and in eastern and coastal regions of China, and the narrowing trend is attributed to six categories diseases, except for sexually transmitted and bloodborne diseases with gradually widened disparity between two groups with surveillance years with IRR from 22.939 in 2013 to 23.291 in 2021 due to large disparity for those who have completed compulsory education.

Interpretation

A huge achievement has been achieved in reducing the burden and disparity of infectious diseases between out-of-school and in-school children, adolescents, and youths in China, particularly for the compulsory education stage population. The priorities for the coming decades will be to extend successful strategies to a broad scope and promote education, particularly for the investment of social health resources and the improvement of personal health literacy in the non-compulsory education stage. This should involve extending the years of compulsory school, improving sex health education, strengthening monitoring, expanding immunization programs coverage and prioritizing the prevention and control of sexually transmitted diseases and tuberculosis among out-of-school population.

Funding

National Natural Science Foundation of China and Beijing Natural Science Foundation.

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.

The Epidemiology of Influenza and the Associated Vaccines Development in China: A Review

Influenza prevention and control has been one of the biggest challenges encountered in the public health domain. The vaccination against influenza plays a pivotal role in the prevention of influenza, particularly for the elderly and small children. According to the epidemiology of influenza in China, the nation is under a heavy burden of this disease. Therefore, as a contribution to the prevention and control of influenza in China through the provision of relevant information, the present report discusses the production and batch issuance of the influenza vaccine, analysis of the vaccination status and vaccination rate of the influenza vaccine, and the development trend of the influenza vaccine in China.

Cost-Effectiveness of Intranasal Live-Attenuated Influenza Vaccine for Children: A Systematic Review

Introduction: The public health burden of seasonal influenza is significant, and influenza vaccination is the most effective preventive strategy. Nonetheless, the recommendation of influenza immunization in the pediatric population is still underrepresented. Our work aimed to assess the cost-effectiveness of pediatric influenza vaccination with the intranasal live-attenuated influenza vaccine (LAIV). Methods: We performed a systematic review of publications from PubMed/MEDLINE, Embase, and Scopus, covering the period from 1 January 2000 to 30 April 2022. We searched for economic evaluations that studied the impacts of LAIV among children or the pediatric population. Studies that considered incremental cost-effectiveness ratios (ICERs), in terms of cost per gain in life years, quality adjusted life years, or disability-adjusted life years, were covered. The Consensus Health Economic Criteria (CHEC) Extended Checklist was adopted to check the quality of the included studies. Results: Thirteen studies were included for the final review that were of good or excellent quality. The implementation of influenza vaccination with intranasal LAIV in the pediatric population was cost-effective when compared to the immunization strategies for the elderly and the high-risk groups alone or with no vaccination. The efficacy of LAIV for children, vaccination coverage, and the vaccine price were significant factors to the cost-effectiveness of influenza vaccination for children. Another significant contribution to the cost-effectiveness was the herd immunity arising from pediatric immunization against influenza. Conclusions: The implementation of influenza vaccination in the pediatric population with LAIV is cost-effective. Policymakers and health authorities may consider the evidence on the development of the pediatric influenza vaccination in their immunization schedules.