Socioeconomic Inequalities and Vaccine Uptake: An Umbrella Review Protocol

Socioeconomic inequalities in vaccine uptake: A global umbrella review

This global umbrella review aimed to synthesise evidence of socioeconomic inequalities in the uptake of routine vaccinations and identify the mechanisms that may contribute to the association. To our knowledge, no attempt has been made to synthesise the global body of systematic reviews across a variety of vaccines, geographical locations, and measures of SES. The inclusion criteria were as follows: studies assessing vaccination uptake according to education, income, occupation/employment, and/or area-level deprivation; any country or universally recommended routine vaccination (according to the WHO); qualitative or quantitative reviews, published 2011-present. The searches were performed in eight databases. The screening process followed PRISMA-E guidelines, each stage was performed by one reviewer, and a 10% sample checked by a second for consistency. Included reviews underwent data extraction, quality appraisal (AMSTAR-2), and narrative synthesis according to country-context. After deduplication, 9,163 reports underwent title and abstract screening, leaving 119 full texts to be assessed for eligibility. Overall, 26 studies were included in the umbrella review. Evidence for lower uptake amongst disadvantaged SES individuals was found in all 26 reviews. However, 17 reviews showed mixed results, as inverse associations were also identified (lower uptake for advantaged SES, and/or higher uptake for disadvantaged SES). Those that explored high-income countries had a greater prevalence of mixed findings than those focusing on low/middle-income countries. The two most frequently cited mechanisms were vaccination knowledge, and confidence in vaccination or vaccination providers. These mechanisms were often understood by review authors as varying by level of education. We find socioeconomic differences in routine vaccination uptake, but the association did not always follow a gradient. Whilst education may be associated with uptake globally, our study indicates that its role varies by country-context. A limitation is the overlap of some primary studies across the included systematic reviews.

Far-right political ideology and COVID-19 vaccine hesitancy: Multilevel analysis of 21 European countries

BACKGROUND

Far-right political parties across the EU have downplayed the risk of COVID-19 and have expressed skepticism toward the safety of the COVID-19 vaccine. This may affect the risk perception of people who support far-right parties and may be associated with an elevated risk of vaccine hesitancy. We aimed to explore if voting far-right is associated with COVID-19 vaccine hesitancy and if the association varies by individual and country-level factors.

METHODS

We used cross-sectional data from 28,057 individuals nested in 21 countries who participated in the tenth round of the European Social Survey (ESS). COVID-19 vaccine hesitancy was assessed by asking respondents whether they will get vaccinated against COVID-19. Voting behavior was measured by asking respondents which party they voted for in the last election. To test the association between far-right voting and COVID-19 hesitancy, we applied a series of multilevel regression models. We additionally ran models including interaction terms to test if the association differs by sociodemographic characteristics (e.g., institutional trust) or contextual factors (e.g., income inequality).

RESULTS

We found that far-right voters were 2.7 times more likely to be COVID-19 vaccine hesitant compared to center voters (PR: 2.69, 95% CI: 1.46-4.94). The association persisted even after controlling for institutional trust and social participation (adjusted PR: 2.15, 95% CI: 1.35-3.42). None of the tested interaction terms were significant suggesting that the association between political ideology and COVID-19 vaccine hesitancy does not differ by sociodemographic characteristics or contextual factors.

CONCLUSION

Voting for far-right parties is associated with COVID-19 vaccine hesitancy. The association is similar among European countries, regardless of how stringent the public health measures were and magnitude of income inequality in each country. Our findings call for a more in-depth investigation of why, how and under which conditions political ideology affects vaccination behavior.