A meta-analysis of influenza vaccination following correspondence: Considerations for COVID-19

Effect of vaccine education intervention on vaccine uptake and vaccine knowledge among older adults: A systematic review with meta-analysis

Educational intervention is one approach for providing vaccine knowledge and encouraging vaccine uptake. However, up till now, no systematic review reporting the effectiveness of vaccine educational intervention on vaccine uptake and/or knowledge enhancement for disease preventeable by the vaccine of interest, compared to conventional/standard or no intervention, for older adults aged 60 or above was found. Six databases, including PubMed, OVID, CINAHL, Web of Science, the Cochrane Library, and the British Nursing Index, were searched. Vaccine educational interventions in this study were interventions that encourage vaccine uptake and/or provide knowledge enhancement on diseases prevented by the vaccine. Conventional/standard or no intervention refers to vaccine educational intervention that existed prior to the commencement of the intervention or no vaccine educational intervention was performed at all. All included studies were randomized control trials. The appraisal was performed with the Cochrane Risk of Bias Tool Version 1 (RoB 1). Meta-analysis was performed with RevMan Web. Ten studies were included in the meta-analysis, with a sample size of 419,523. This review demonstrated that vaccine educational intervention improves vaccine uptake (Relative Risk: 1.19, p = 0.008, 95 % confidence interval: 1.05-1.35). Furthermore, interactive vaccine educational intervention had a statistically significant effect on improving vaccine uptake among older adults (Relative Risk = 1.33, 95 % confidence interval: 1.08-1.62, p = 0.006). Neither continuous nor conducted once only intervention were found to have statistically significant improvement in vaccine uptake in the subgroup analysis. Vaccine educational interventions were found to have statistically significant effects on vaccine knowledge enhancement (Mean Difference: 0.42, 95 % confidence interval: 0.11-0.74, p = 0.008). The findings demonstrate that educational interventions significantly encourage vaccine uptake and knowledge enhancement in older adults. However, the limited amount of included literature and the high heterogeneity observed may limit the generalizability of the findings of this study. Further RCTs are recommended to bring more assertive results.

Estimating the effects of interventions on increasing vaccination: systematic review and meta-analysis

As global vaccination rates have reached their lowest point in nearly 15 years, effective interventions are being required globally to promote vaccination; however, there is a lack of rigorous evaluation of the effect of various interventions. Through a global synthesis, we analysed data from approximately 6 125 795 participants across 319 studies in 41 countries to reveal the global landscape of four intervention themes and to assess their effectiveness in increasing vaccination rates. We found an overall positive effect of the interventions across four main themes on improving vaccination. Specifically, dialogue-based interventions increased vaccination rates by 43.1% (95% CI: 29.8 to 57.9%, with effect sizes measured as relative risks (RRs)), though they may not always be effective in adolescents or in the sample with a higher percentage of male participants. Incentive-based interventions, whether implemented alone or combined with other intervention themes, failed to demonstrate a significant effect in children. Reminder/recall-based interventions were also effective for promoting vaccination (38.5% increase, 95% CI: 28.9 to 48.9%), particularly for completing vaccine series. Multi-component interventions exhibited excellent effectiveness in vaccination (54.3% increase, 95% CI: 40.5 to 69.6%), with the combination of dialogue, incentive and reminder/recall proving more effective than other multi-component interventions, but showing no significant effects in populations with high initial vaccination rates. However, we found that in most cases combining additional interventions with a single intervention may not significantly improve their effectiveness, especially for incentive-based interventions, but dialogue-based and reminder/recall-based interventions appear to be beneficial in some specific combinations. These findings underscore the importance of governments, public health officials and advocacy groups implementing appropriate vaccine interventions by selecting interventions tailored to specific populations, strategically promoting the completion of vaccine series and effectively combining interventions to promote global vaccination and save more lives.

A systematic review and meta-analysis of strategies to promote vaccination uptake

Although immunization can dramatically curb the mortality and morbidity associated with vaccine-preventable diseases, vaccination uptake remains suboptimal in many areas of the world. Here, in this meta-analysis, we analysed the results from 88 eligible randomized controlled trials testing interventions to increase vaccination uptake with 1,628,768 participants from 17 countries with variable development levels (for example, Human Development Index ranging from 0.485 to 0.955). We estimated the efficacy of seven intervention strategies including increasing access to vaccination, sending vaccination reminders, providing incentives, supplying information, correcting misinformation, promoting both active and passive motivation and teaching behavioural skills. We showed that the odds of vaccination were 1.5 (95% confidence interval, 1.27 to 1.77) times higher for intervention than control conditions. Among the intervention strategies, using incentives and increasing access were most promising in improving vaccination uptake, with the access strategy being particularly effective in countries with lower incomes and less access to healthcare.

Behavioural evidence on COVID-19 vaccine uptake

OBJECTIVES

The World Health Organization has declared that COVID-19 is no longer a public health emergency of international concern. Nevertheless, it remains a public health issue, and seasonal vaccinations, at the same time of year as influenza vaccinations, will be necessary. When the first vaccines were administered in 2020, decision-makers had to make assumptions about the best methods to communicate and administer vaccines to increase uptake. Now, a body of evidence can inform these decisions.

STUDY DESIGN

A narrative review written by three behavioural scientists who design research for policy.

METHODS

We searched the PubMed database for: (i) reviews of interventions to increase uptake of COVID-19 or influenza vaccines and (ii) empirical studies on uptake of COVID-19 and influenza vaccines. In addition, registered trials gathered by a Cochrane scoping review of interventions to increase uptake of COVID-19 vaccines were searched for updated results.

RESULTS

Results centre around two aspects of a vaccination campaign of interest to policymakers: communication and administration. Results suggest that communications highlighting the personal benefits of vaccination are likely to be more effective than those highlighting collective benefits. The efficacy of vaccination may be underestimated and stressing efficacy as a strong personal benefit may increase uptake. Keeping vaccines free, sending personalised messages, reminders and prebooked appointment times may also increase uptake.

CONCLUSIONS

There is now a body of evidence from behavioural science that suggests how vaccination campaigns for COVID-19 can be structured to increase uptake. These recommendations may be useful to policymakers considering seasonal vaccination campaigns and to researchers generating hypotheses for country-specific trials.

Increasing Influenza Vaccination Uptake by Sending Reminders: A Representative Cross-Sectional Study on the Preferences of Italian Adults

Evidence from countries that achieved a high seasonal influenza vaccination (SIV) coverage suggests that reminders to get vaccinated may increase SIV uptake. The goal of this study was to explore the experience and attitudes of Italian adults toward an active invitation to receive SIV, triggered by different sources and delivered via different communication channels, and to assess the projected benefits of this strategy. A cross-sectional survey on a representative sample of Italian adults was conducted by using computer-assisted web interviewing. Responses from 2513 subjects were analyzed. A total of 52.2% of individuals previously received invitations to undergo SIV and compared with people who did not receive any reminder were three times more likely (68.2% vs. 22.2%) to be vaccinated in the last season. Compared with other sources, reminders sent by general practitioners (GPs) were perceived as the most attractive. As for communication channels, most participants preferred text/instant messaging (24.6%) or email (27.2%), suggesting an acceleration in the Italian digital transformation triggered by the COVID-19 pandemic. Conversely, traditional postal letters or phone calls were preferred by only 17.0% and 8.6% of respondents, respectively. Reminders sent by GPs via text/instant messages or email are a valuable option for increasing SIV uptake among Italian adults.

Determinants of COVID-19 vaccine fatigue

There is growing concern that Coronavirus Disease 2019 (COVID-19) vaccine fatigue will be a major obstacle in maintaining immunity in the general population. In this study, we assessed vaccine acceptance in future scenarios in two conjoint experiments, investigating determinants such as new vaccines, communication, costs/incentives and legal rules. The experiments were embedded in an online survey (n = 6,357 participants) conducted in two European countries (Austria and Italy). Our results suggest that vaccination campaigns should be tailored to subgroups based on their vaccination status. Among the unvaccinated, campaign messages conveying community spirit had a positive effect (0.343, confidence interval (CI) 0.019-0.666), whereas offering positive incentives, such as a cash reward (0.722, CI 0.429-1.014) or voucher (0.670, CI 0.373-0.967), was pivotal to the decision-making of those vaccinated once or twice. Among the triple vaccinated, vaccination readiness increased when adapted vaccines were offered (0.279, CI 0.182-0.377), but costs (-0.795, CI -0.935 to -0.654) and medical dissensus (-0.161, CI -0.293 to -0.030) reduced their likelihood to get vaccinated. We conclude that failing to mobilize the triple vaccinated is likely to result in booster vaccination rates falling short of expectations. For long-term success, measures fostering institutional trust should be considered. These results provide guidance to those responsible for future COVID-19 vaccination campaigns.

Associations between 5-year influenza vaccination and sociodemographic factors and healthcare access among Arkansans

Despite wide availability, only 50.2% of the United States (US) adult population and 50.3% of adult Arkansans were vaccinated for influenza during the 2020-2021 influenza season. The proportion of the population vaccinated for influenza varies by age, sex, race/ethnicity, education, rural/urban residence, and income. However, measures of healthcare access have not been adequately investigated as predictors of influenza vaccination. Using a large, statewide random sample, this study examined 5-year influenza vaccination among Arkansans by sociodemographic characteristics (age, sex, race/ethnicity, education, rural/urban residence), general vaccine hesitancy, and healthcare access (having a primary care provider, having health insurance, forgoing health care due to cost, and frequency of doctor checkups). Older age, being female, being Hispanic, having a bachelor's degree or higher, having a primary care provider, visiting a doctor for a checkup in the past two years, and lack of hesitancy towards vaccines were significant predictors of receiving influenza vaccination.