Can targeted messages reduce COVID-19 vaccination hesitancy? A randomized trial

The power of the family in times of pandemic: Cross-country evidence from 93 countries

The majority of the hospitalizations and deaths associated with COVID-19 occurred in people over the age of 65. In addition, previous studies have shown that intergenerational contacts played a key role in COVID-19-related infection and fatality. This paper utilized two large-scale multinational surveys to uncover the important role of family ties in infection prevention across 93 countries. Using the World Values Survey, we measured country-level family ties emphasizing respondents' view of their parents. We elicited individual willingness to uptake infection prevention measures from a panel study conducted each month in the early phase of the COVID-19 pandemic between March 2020 and July 2021. We find that in countries with stronger family ties, people show more support for non-pharmaceutical interventions and higher vaccine acceptance; moreover, young people are more supportive of mandatory vaccination. The association between strength of family ties and compliance with infection prevention measures was salient before COVID-19 vaccines became available and was persistent before the global vaccination coverage reached 25%.

Deciphering Discord: How Conflicting Information and Political Ideology Shape Public Attitude Toward PFAS Regulation

Per- and polyfluorinated substances (PFAS) contamination is an emerging environmental and health risk facing the world. This study examines the impact of conflicting information on Americans' attitude toward PFAS regulation and intention to engage in mitigation behaviors through a one-way, between-subjects experiment. Participants were 1,062 U.S. adults recruited from CloudResearch. Results showed that compared to participants exposed to consistent information, those exposed to conflicting information displayed less favorable attitude toward existing regulation, which led to lower intention to support related policies and to engage in mitigation behaviors. Political ideology moderated these relationships, with stronger experimental effects among conservatives. These findings underscore the importance of conveying consistent risk messages, especially when multiple stakeholders are involved.

An effective COVID-19 vaccine hesitancy intervention focused on the relative risks of vaccination and infection

We designed the Relative Risk Tool (RRT) to help people assess the relative risks associated with COVID-19 vaccination and infection. In May 2022 (N = 400) and November 2022 (N = 615), U.S. residents participated in a survey that included questions about the risks of vaccination and infection. In both cohorts, we found an association between relative risk perception and vaccine hesitancy. Participants in the May cohort were randomly assigned an intervention: to see information from the RRT or the Centers for Disease Control and Prevention (CDC). After the intervention, participants answered the same questions about risk perception and vaccination intent again. The RRT was more effective than the CDC at changing risk perception and increasing vaccination intent. In November, the survey structure was the same, but the RRT was the only intervention included, and we confirmed that the RRT was effective at changing opinions in this new sample. Importantly, the RRT provided accurate information about the risks of serious adverse outcomes to vaccination and still increased vaccination intent. Our work suggests that the RRT helps people assess relative risk, which can in turn help empower them to make informed decisions and ultimately reduce vaccine hesitancy.

Say it right: measuring the impact of different communication strategies on the decision to get vaccinated

BACKGROUND

Vaccine hesitancy is a concerning menace to the control of vaccine-preventable diseases. Effective health communication could promote an overall understanding of the importance, risks, and benefits of vaccination and reduce vaccine hesitancy.

METHODS

In this survey, four fictitious newspaper articles addressing an emerging bogus disease and its vaccine were randomly assigned to participants. The first version focused on information about the disease; the second was akin to the first, including a case description and image. The third version focused on vaccine safety/efficacy; the fourth version was like the third, including a case description and image. After reading a single version of the article, participants responded if they would take the vaccine and if they would vaccinate their children. We used chi-squared tests for comparisons and investigated interactions with vaccine-hesitant attitudes.

RESULTS

We included 5233 participants between August/2021 and January/2022; 790 were caregivers of a child ≤ 5 years old, and 15% had prior vaccine hesitancy. Although most declared intention to take the vaccine, the percentage was highest among those exposed to the newspaper article focusing on the vaccine safety/efficacy with the case description and picture (91%; 95% confidence interval 89-92%), and lowest among participants exposed to the article focusing on the disease with no case description (84%; 95% confidence interval 82-86%). Similar trends were observed in the intention of offspring vaccination. We found evidence of effect modification by vaccine-hesitant attitudes, with a higher impact of communication focusing on vaccine safety/efficacy compared to that focusing on disease characteristics among hesitant participants.

CONCLUSION

Communication strategies focusing on different aspects of the disease-vaccine duet may impact vaccine hesitancy, and storytelling/emotive imagery descriptions may improve risk perception and vaccine uptake. Moreover, the effect of message framing strategies may differ according to previous vaccine hesitant attitudes.

Assessment of Efficacy and Safety of mRNA COVID-19 Vaccines in Children Aged 5 to 11 Years: A Systematic Review and Meta-analysis

Importance

Evidence of the efficacy and safety of messenger RNA (mRNA) COVID-19 vaccines in children aged 5 to 11 years has been emerging. Collecting these data will inform clinicians, families, and policy makers.

Objective

To evaluate the efficacy and safety of mRNA COVID-19 vaccines in children aged 5 to 11 years in a systematic review and meta-analysis.

Data Sources

PubMed and Embase databases were searched on September 29, 2022, without language restrictions.

Study Selection

Randomized clinical trials and observational studies comparing vaccinated vs unvaccinated children aged 5 to 11 years and reporting efficacy or safety outcomes were included. Studies reporting safety outcomes in vaccinated children only (ie, no control group) were also included.

Data Extraction and Synthesis

Two investigators independently extracted relevant data from each study. Odds ratios (ORs) for efficacy and safety outcomes and incidences of adverse events (AEs) following vaccination were synthesized using a random-effects model. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses and Meta-analysis of Observational Studies in Epidemiology reporting guidelines.

Main Outcomes and Measures

The primary outcome was SARS-CoV-2 infections with or without symptoms. The secondary outcomes included symptomatic SARS-CoV-2 infections, hospitalizations, and multisystem inflammatory syndrome in children. The incidences of each AE following vaccination were also evaluated.

Results

Two randomized clinical trials and 15 observational studies involving 10 935 541 vaccinated children (median or mean age range, 8.0-9.5 years) and 2 635 251 unvaccinated children (median or mean age range, 7.0-9.5 years) were included. Two-dose mRNA COVID-19 vaccination compared with no vaccination was associated with lower risks of SARS-CoV-2 infections with or without symptoms (OR, 0.47; 95% CI, 0.35-0.64), symptomatic SARS-CoV-2 infections (OR, 0.53; 95% CI, 0.41-0.70), hospitalizations (OR, 0.32; 95% CI, 0.15-0.68), and multisystem inflammatory syndrome in children (OR, 0.05; 95% CI, 0.02-0.10). Two randomized clinical trials and 5 observational studies investigated AEs among vaccinated children. Most vaccinated children experienced at least 1 local AE following the first injection (32 494 of 55 959 [86.3%]) and second injection (28 135 of 46 447 [86.3%]). Vaccination was associated with a higher risk of any AEs compared with placebo (OR, 1.92; 95% CI, 1.26-2.91). The incidence of AEs that prevented normal daily activities was 8.8% (95% CI, 5.4%-14.2%) and that of myocarditis was estimated to be 1.8 per million (95% CI, 0.000%-0.001%) following the second injection.

Conclusions and Relevance

In this systematic review and meta-analysis, COVID-19 mRNA vaccines among children aged 5 to 11 years were associated with measures of efficacy in preventing SARS-CoV-2 infection and severe COVID-19-related illnesses. While most children developed local AEs, severe AEs were rare, and most of AEs resolved within several days. These data provide evidence for future recommendations.

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.