Can uptake of childhood influenza immunisation through schools and GP practices be increased through behaviourally-informed invitation letters and reminders: two pragmatic randomized controlled trials

Evaluating the impact of school-based influenza vaccination programme on absenteeism and outbreaks at schools in Hong Kong: a retrospective cohort study protocol

INTRODUCTION

Seasonal influenza causes annual school breaks and student absenteeism in Hong Kong schools and kindergartens. This proposal aims to conduct a retrospective cohort study to evaluate the impact of a school-based influenza vaccination (SIV) programme on absenteeism and outbreaks at schools in Hong Kong.

METHODS

The study will compare schools that implemented the SIV programme with schools that did not. The data will be sourced from school records, encompassing absenteeism records, outbreak reports, and vaccination rates. We will recruit 1000 students from 381 schools and kindergartens in 18 districts of Hong Kong starting June 2024. The primary outcome measures will include absenteeism rates due to influenza and school influenza outbreaks. Secondary outcomes will consist of vaccination coverage rates and the impact of the SIV programme on hospitalisations due to influenza-like illness. A t-test will be conducted to compare the outcomes between schools with and without the SIV programme.

ETHICS AND DISSEMINATION

The school completed signing the participants' informed consent form before reporting the data to us. Our study has been approved by the Hospital Authority Hong Kong West Cluster IRB Committee (IRB No: UW 17-111) and was a subtopic of the research "The estimated age-group specific influenza vaccine coverage rates in Hong Kong and the impact of the school outreach vaccination program".

TRIAL REGISTRATION

This study will be retrospectively registered.

Use of invitations and reminders are associated with higher levels of Herpes zoster (shingles) vaccination uptake. A cross-sectional survey of general practices in Wales, and ecological analysis of uptake data, 2022

In 2013, shingles vaccination was introduced in Wales as a routine immunisation programme for older adults. Invitation for this vaccination has historically been recommended but not mandated by vaccination policy. We surveyed general practices to investigate if invitations and reminders are associated with higher uptake of shingles vaccine. Using data from general practices, we calculated practice-level shingles vaccine uptake between 01/07/2021 and 31/06/2022 for registered patients aged 70-84 years. We distributed an online survey via email to all general practices in Wales on their use of vaccination invitations and reminders, method of invitations, and characteristics of their vaccination delivery. We used linear regression to calculate coefficients and 95 %CI to measure associations between invitations and vaccine uptake, adjusting for key demographics, with a multi-level component to account for similarities between general practices within the same health board. Survey response rate was 37 % (143/384). Median vaccine uptake for responding general practices was 57 % (IQR 50-68 %) compared to 58 % (IQR 48-68 %) nationally. General practices inviting all eligible patients (n = 95) had a 9 % (95 %CI 6-13 %) higher vaccination uptake compared to those inviting none or some (n = 48, p < 0.001). Of practices sending invitations, those who reminded all patients (n = 42) had a 6 % (95 %CI 1-11 %, p = 0.02) higher uptake compared to those that reminded none (n = 30). Practice size was associated with higher uptake, with small practices (n = 11, p = 0.02) having coverage 9 % (95 %CI 2-16 %) higher compared to the reference population (medium-sized practices, n = 78). General practices inviting and reminding all eligible patients for shingles vaccination have a higher uptake compared to those inviting and reminding only some or none. From September 2023, shingles vaccination policy in Wales has been updated to explicitly mandate effective universal call and recall mechanisms in general practices.

Has the COVID-19 Pandemic Changed Parental Attitudes and Beliefs Regarding Vaccinating Their Children against the Flu?

BACKGROUND

This study assessed whether the COVID-19 pandemic has altered parents' attitudes toward vaccinating their children against the flu and barriers to school-based vaccination programs.

METHODS

A cross-sectional online survey was conducted with 975 parents of children aged 6 months to 11 years between 21-31 December 2022. A multivariate regression was performed to determine predictors of parents' willingness to vaccinate their children against the flu in the winter of 2023.

RESULTS

45% of parents did not plan to vaccinate their children against the flu, citing concerns about side effects and vaccine effectiveness; 39% already vaccinated their children, and 41% of them reported an increased intention to vaccinate following the pandemic. Only 37% of parents chose school-based vaccination programs, mainly due to a preference for HMO clinics and a lack of available nurses at school. The Health Belief Model variables, namely, perceived susceptibility, severity, and benefits, displayed the largest effect sizes.

CONCLUSIONS

Healthcare providers and public health officials should address parents' concerns about flu vaccine safety and efficacy to improve vaccination rates among children. Notably, the pandemic has increased vaccine receptivity among some parents. Enhancing accessibility to nursing staff in student health facilities could help boost vaccine uptake.