Determinants of COVID-19 Vaccine Hesitancy in Portuguese-Speaking Countries: A Structural Equations Modeling Approach

Conspiracy narratives and vaccine hesitancy: a scoping review of prevalence, impact, and interventions

Believing conspiracy narratives is frequently assumed to be a major cause of vaccine hesitancy, i.e., the tendency to forgo vaccination despite its availability. In this scoping review, we synthesise and critically evaluate studies that assess i) the occurrence of vaccine-related conspiracy narratives on the internet, ii) the prevalence of belief in vaccine-related conspiracy narratives, iii) the relationship between belief in conspiracy narratives and vaccination intention or vaccination uptake, and iv) interventions that reduce the impact of conspiracy narratives on vaccination intention.In July 2022, we conducted a literature search using three databases: PubMed, PsychInfo, and Web of Science. Following the PRISMA approach, of the 500 initially identified articles, 205 were eligible and analysed.The majority of identified studies were conducted in Europe and North America, were published in 2021 and 2022, and investigated conspiracy narratives around the COVID-19 vaccination. The prevalence of belief in various vaccine-related conspiracy narratives varied greatly across studies, from 2 to 77%. We identified seven experimental studies investigating the effect of exposure to conspiracy narratives on vaccination intentions, of which six indicated a small negative effect. These findings are complemented by the evidence from over 100 correlative studies showing a significant negative relationship between conspiracy beliefs and vaccination intention or uptake. Additionally, the review identified interventions (e.g., social norm feedback, fact-checking labels, or prebunking) that decreased beliefs in vaccine-related conspiracy narratives and, in some cases, also increased vaccination intentions. Yet, these interventions had only small effects.In summary, the review revealed that vaccine-related conspiracy narratives have spread to varying degrees and can influence vaccination decisions. Causal relationships between conspiracy beliefs and vaccination intentions remain underexplored. Further, the review identified a need for more research on interventions that can reduce the impact of conspiracy narratives.

A scoping review of COVID-19 vaccine hesitancy: refusal rate, associated factors, and strategies to reduce

Objective

This study aimed to investigate the evidence regarding vaccine hesitancy including refusal rate, associated factors, and potential strategies to reduce it.

Methods

This is a scoping review. Three main databases such as PubMed, Scopus, and Web of Science were searched from 1 January 2020 to 1 January 2023. All original studies in the English language that investigated one of our domains (vaccine hesitancy rate, factors associated with vaccine hesitancy, and the ways/interventions to overcome or decrease vaccine hesitancy) among the general population were included in this study. The data were charted using tables and figures. In addition, a content analysis was conducted using the 3C model of vaccine hesitancy (Confidence, Complacency, and Convenience) that was previously introduced by the WHO.

Results

Finally, 184 studies were included in this review. Of these, 165, 181, and 124 studies reported the vaccine hesitancy rate, associated factors, and interventions to reduce or overcome vaccine hesitancy, respectively. Factors affecting the hesitancy rate were categorized into 4 themes and 18 sub-themes (contextual factors, confidence barriers, complacency barriers, and convenience barriers).

Conclusion

Vaccine hesitancy (VH) rate and the factors affecting it are different according to different populations, contexts, and data collection tools that need to be investigated in specific populations and contexts. The need to conduct studies at the national and international levels regarding the reasons for vaccine refusal, the factors affecting it, and ways to deal with it still remains. Designing a comprehensive tool will facilitate comparisons between different populations and different locations.

Determining factors for COVID-19 vaccine hesitancy among Brazilians: a study using structural equation modeling

OBJECTIVES

to investigate the factors influencing vaccine hesitancy against COVID-19 among Brazilians.

METHODS

this research employed an observational and analytical approach, utilizing a web-based survey. Data collection took place in 2020, and data analysis was conducted using structural equation modeling.

RESULTS

the prevalence of vaccine hesitancy was found to be 27.5% (1182 individuals). There is a negative correlation between belief in conspiracy theories and social influence. Among the various beliefs associated with vaccination intentions, only conspiracy beliefs exhibited significant predictive value. Thus, the findings suggest that personal beliefs significantly impact hesitancy towards vaccination, and also indicate that trust in governmental bodies is inversely related to hesitancy.

CONCLUSIONS

vaccine hesitancy emerges as a multifaceted phenomenon influenced by a complex array of factors, including personal beliefs, trust in governmental bodies, and healthcare systems.

Quantitative Synthesis of Factors Associated with COVID-19 Vaccine Acceptance and Vaccine Hesitancy in 185 Countries

Mass vaccination against COVID-19 is the best method to ensure herd immunity in order to curb the effect of the pandemic on the global economy. It is therefore important to assess the determinants of COVID-19 vaccine acceptance and hesitancy on a global scale. Factors were recorded from cross-sectional studies analyzed with t-Test, ANOVA, correlation, and meta-regression analyses and synthesized to identify global trends in order to inform policy. We registered the protocol (ID: CRD42022350418) and used standard Cochrane methods and PRISMA guidelines to collect and synthesize cross-sectional articles published between January 2020 and August 2023. A total of 67 articles with 576 studies from 185 countries involving 3081,766 participants were included in this synthesis. Global COVID-19 vaccine acceptance was 65.27% (95% CI; 62.72-67.84%), while global vaccine hesitancy stood at 32.1% (95% CI; 29.05-35.17%). One-Way ANOVA showed that there was no significant difference in the percentage Gross Domestic Product spent on vaccine procurement across the World Bank income levels (p < 0.187). There was a significant difference of vaccine acceptance (p < 0.001) and vaccine hesitancy (p < 0.005) across the different World Bank Income levels. World Bank income level had a strong influence on COVID-19 vaccine acceptance (p < 0.0004) and hesitancy (p < 0.003) but percentage Gross Domestic Product spent on vaccine procurement did not. There was no correlation between percentage Gross Domestic Product spent on vaccine procurement and COVID-19 vaccine acceptance (r = -0.11, p < 0.164) or vaccine hesitancy (r = -0.09, p < 0.234). Meta-regression analysis showed that living in an urban setting (OR = 4.83, 95% CI; 0.67-212.8), rural setting (OR = 2.53, 95% CI; 0.29-119.33), older (OR = 1.98, 95% CI; 0.99-4.07), higher education (OR = 1.76, 95% CI; 0.85-3.81), and being a low income earner (OR = 2.85, 95% CI; 0.45-30.63) increased the odds of high COVID-19 vaccine acceptance. Factors that increased the odds of high COVID-19 vaccine hesitancy were no influenza vaccine (OR = 33.06, 95% CI; 5.03-1395.01), mistrust for vaccines (OR = 3.91, 95% CI; 1.92-8.24), complacency (OR = 2.86, 95% CI; 1.02-8.83), pregnancy (OR = 2.3, 95% CI; 0.12-141.76), taking traditional herbs (OR = 2.15, 95% CI; 0.52-10.42), being female (OR = 1.53, 95% CI; 0.78-3.01), and safety concerns (OR = 1.29, 95% CI; 0.67-2.51). We proposed a number of recommendations to increase vaccine acceptance and ensure global herd immunity against COVID-19.

COVID-19 vaccine hesitancy worldwide and its associated factors: a systematic review and meta-analysis

Introduction

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has taken a toll on humans, and the development of effective vaccines has been a promising tool to end the pandemic. However, for a vaccination program to be successful, a considerable proportion of the community must be vaccinated. Hence, public acceptance of coronavirus disease 2019 (COVID-19) vaccines has become the key to controlling the pandemic. Recent studies have shown vaccine hesitancy increasing over time. This systematic review aims to evaluate the COVID-19 vaccine hesitancy rate and related factors in different communities.

Method

A comprehensive search was performed in MEDLINE (via PubMed), Scopus, and Web of Science from January 1, 2019 to January 31, 2022. All relevant descriptive and observational studies (cross-sectional and longitudinal) on vaccine hesitancy and acceptance were included in this systematic review. In the meta-analysis, odds ratio (OR) was used to assess the effects of population characteristics on vaccine hesitancy, and event rate (acceptance rate) was the effect measure for overall acceptance. Publication bias was assessed using the funnel plot, Egger's test, and trim-and-fill methods.

Result

A total of 135 out of 6,417 studies were included after screening. A meta-analysis of 114 studies, including 849,911 participants, showed an overall acceptance rate of 63.1%. In addition, men, married individuals, educated people, those with a history of flu vaccination, those with higher income levels, those with comorbidities, and people living in urban areas were less hesitant.

Conclusion

Increasing public awareness of the importance of COVID-19 vaccines in overcoming the pandemic is crucial. Being men, living in an urban region, being married or educated, having a history of influenza vaccination, having a higher level of income status, and having a history of comorbidities are associated with higher COVID-19 vaccine acceptance.

Do Electronic Health Literacy and Online Health Information-Seeking Behavior Mediate the Effects of Socio-Demographic Factors on COVID-19- and Non-communicable Disease-Related Behaviors Among Myanmar Migrants in Southern Thailand?

Introduction Myanmar migrants in Thailand are vulnerable to COVID-19 and non-communicable disease (NCD) risk behaviors, influenced by socio-demographic factors. In the digital age, migrants can seek extensive health information online, and their ability to understand and use electronic health information, which is known as electronic health literacy (e-Health literacy), becomes critical in making decisions about their health behaviors. This study aims to investigate the potential mediating roles of online health information-seeking and e-Health literacy in the associations between socio-demographic factors and COVID-19- and NCD-related behaviors. Methods Our study was conducted in 2022, involving 1,050 Myanmar migrants in two southern Thai cities. Data on socio-demographic factors, e-Health literacy, online health information seeking, COVID-19-related behaviors (adherence to COVID-19 protective behavior (CPB), vaccination), and NCD risk behaviors (smoking, betel chewing, alcohol consumption, substance abuse) were collected. Structural equation modeling (SEM) was employed to analyze the hypothesized relationships. Results Nearly all migrants received the COVID-19 vaccination in two doses and above, with reasonable good adherence to CPB. Migrants exhibited risky NCD-related behaviors, including current smoking (26.8%), alcohol consumption (17.5%), and betel chewing (25.8%). Approximately three-quarters (73.4%) had a limited e-Health literacy level, and the vast majority did not search for online health information. Their COVID-19- and NCD-related behaviors were directly influenced by socio-demographic factors without the significant mediation roles of e-Health literacy and online health information seeking. Conclusions Myanmar migrant workers in Southern Thailand had reasonably good practices in COVID-19-related behaviors despite engaging in risky NCD-related behaviors. These outcome behaviors were directly influenced by their socio-demographic factors, without the significant mediation roles of e-Health literacy and online health information seeking. The findings suggest that diverse interventions beyond e-Health strategies for future pandemic mitigation and enhancement of their health behaviors are needed.

Analysis of the COVID-19 vaccine willingness and hesitancy among parents of healthy children aged 6 months-4 years: a cross-sectional survey in Italy

Introduction

In Italy, since December 2022, the COVID-19 vaccination has been extended to children aged 6 months-4 years with conditions of fragility and to those healthy at the request of the parent. The purposes of the cross-sectional survey were to determine the willingness and hesitancy of the parents/guardians to have their healthy children vaccinated against COVID-19.

Methods

The survey was performed among 389 parents/guardians with a child aged 6 months-4 years randomly selected from seven kindergartens and eight nursery schools in the geographic area of Naples, Italy.

Results

Only 10.5% were very concerned about the risk of infection, and the mean values regarding the perceived utility and safety of the COVID-19 vaccine were 3.3 and 3.2, respectively. Only 13.7% of participants were willing to consent to vaccinate the selected child against COVID-19, while 20.1% were uncertain and 66.2% did not intend. Parents/guardians of older children, those who received information about the COVID-19 vaccine from physicians or pediatricians, those who believed that the COVID-19 vaccine was useful, and those with lower hesitancy regarding the COVID-19 vaccine were more willing to vaccinate their child. The mean Parent Attitudes About Childhood Vaccines (PACV-5) score was 5.6, with 33.1% of respondents who were identified as highly hesitant toward COVID-19 vaccination (score ≥ 7). Parents/guardians with a lower perceived safety of the COVID-19 vaccine were more likely to be highly hesitant.

Discussion

The findings reveal the need to improve community-based education campaigns and effective promotion of the COVID-19 vaccination to increase willingness and address parental safety concerns.

Misinformation about COVID-19 among middle-aged and older migrants residing in Brazil and Portugal

OBJECTIVE

The aim of this study was to assess the prevalence of COVID-19 misinformation among migrants aged 50 or older residing in Brazil and Portugal.

METHOD

This was a cross-sectional analytical study conducted among migrants from Portuguese-speaking countries living in Brazil and Portugal, who were 50 years of age or older. The prevalence ratios (PR) were estimated using the Poisson regression model.

RESULTS

Out of the 304 participants included in the study, 188 (61.8%) agreed with at least one piece of misinformation. Factors such as having a religious affiliation (aPR: 1.24), higher educational attainment (aPR: 1.17), knowing someone who died from COVID-19 (aPR: 1.78), and having no intention to get vaccinated (aPR: 1.36) were associated with a higher likelihood of agreeing with COVID-19 misinformation.

CONCLUSION

The findings suggest that access to misinformation was influenced by social, economic, and religious factors among elderly migrants with low digital literacy, thus contributing to the dissemination of false content within this population.

Agreement with COVID-19 disinformation among Portuguese-speaking older adults: an international study

OBJECTIVES

to assess agreement with COVID-19 disinformation among Portuguese-speaking individuals aged 50 years or older.

METHODS

a descriptive and analytical study involving 1,214 older adults born in Portuguese-speaking countries. Data collection occurred through online information mining to recognize COVID-19 and disinformation content, and the application of a structured questionnaire.

RESULTS

agreement with disinformation content was 65.2%. Residing outside Brazil is a protective factor for agreement with disinformation content, and those who believe in the truthfulness of the information sources they receive were 31% more likely to agree with disinformation content.

CONCLUSIONS

there is a high prevalence of disinformation among the older population in two Portuguese-speaking countries, which should raise the attention of healthcare professionals and guide coping strategies.

COVID-19 vaccine hesitancy: A Systematic review of cognitive determinants

Background: Although mass vaccination is considered one of the most effective public health strategies during the pandemic, in the COVID-19 era, many people considered vaccines unnecessary and, or doubted the effectiveness of the COVID-19 vaccine. This review aimed to tabulate cognitive causes of COVID-19 vaccination hesitancy, which may help public health policymakers overcome the barriers to mass vaccinations in future pandemics. Methods: For this systematic review, studies pertaining to COVID-19 vaccine hesitancy published up to June 2022 were retrieved from six online databases (Cochrane Library, Google Scholar Medline through PubMed, Scopus, and Web of Science). Inclusion criteria were the studies conducted on people who had a delay in accepting or refusing COVID-19 vaccines, reported the impact of cognitive determinants on vaccine hesitancy, and were written in English in the timeframe of 2020-2022. Results: This systematic review initially reviewed 1171 records. From these 91 articles met the inclusion criteria. The vaccination hesitation rate was 29.72% on average. This systematic review identified several cognitive determinants influencing vaccination hesitancy. Lack of confidence and complacency were the most frequent factors that predicted vaccine hesitancy. Conclusion: The identified prevailing cognitive determinants for COVID-19 vaccine hesitancy indicated that using initiative and effective communication strategies would be a determinant factor in building people's trust in vaccines during the pandemic and mass vaccinations.

Identity resilience, science mistrust, COVID-19 risk and fear predictors of vaccine positivity and vaccination likelihood: A survey of UK and Portuguese samples

Based on Identity Process Theory, we hypothesised that two elements of identity resilience (identity worth and identity continuity) differentially predict variance in COVID-19 fear and risk, science mistrust, vaccine positivity, and vaccination likelihood. Data from an online survey of 643 UK and 485 Portuguese adults collected during March 2021 showed the UK and Portuguese did not differ significantly on vaccination likelihood or identity resilience. UK respondents reported less science mistrust, COVID-19 risk, and fear, but higher vaccine positivity than the Portuguese. Identity worth and identity continuity differed between countries in their effects on science mistrust, COVID-19 fear, risk, vaccine positivity and vaccination likelihood. Science mistrust and COVID-19 fear proved key factors in predicting vaccine positivity and vaccination likelihood. We conclude the roles of discrete elements of identity resilience in health behaviour require further examination and action reducing prevalence of specific forms of science mistrust can improve vaccination likelihood.

Contemporary trends in psychological research on conspiracy beliefs. A systematic review

Background

The number of psychological studies on conspiracy beliefs has been systematically growing for about a dozen years, but in recent years, the trend has intensified. We provided a review covering the psychological literature on conspiracy beliefs from 2018 to 2021. Halfway through this period, the COVID-19 pandemic broke out, accompanied by an explosion of movements based on conspiracy theories, intensifying researchers' interest in this issue.

Methods

Adhering to PRISMA guidelines, the review systematically searched for relevant journal articles published between 2018 and 2021. A search was done on Scopus and Web of Science (only peer-reviewed journals). A study was included if it contained primary empirical data, if specific or general conspiracy belief(s) were measured and if its correlation with at least one other psychological variable was reported. All the studies were grouped for the descriptive analysis according to the methodology used, the participants' characteristics, the continent of origin, the sample size, and the conspiracy beliefs measurement tools. Due to substantial methodological heterogeneity of the studies, narrative synthesis was performed. The five researchers were assigned specific roles at each stage of the analysis to ensure the highest quality of the research.

Results

Following the proposed methodology, 308 full-text articles were assessed for eligibility and 274 articles (417 studies) meeting the inclusion criteria were identified and included in the review. Almost half of the studies (49.6%) were conducted in European countries. The vast majority of the studies (85.7%) were carried out on samples of adult respondents. The research presents antecedents as well as (potential) consequences of conspiracy beliefs. We grouped the antecedents of conspiracy beliefs into six categories: cognitive (e.g., thinking style) motivational (e.g., uncertainty avoidance), personality (e.g., collective narcissism), psychopathology (e.g., Dark Triad traits), political (e.g., ideological orientation), and sociocultural factors (e.g., collectivism).

Conclusion and limitations

The research presents evidence on the links between conspiracy beliefs and a range of attitudes and behaviors considered unfavorable from the point of view of individuals and of the society at large. It turned out that different constructs of conspiracy thinking interact with each other. The limitations of the study are discussed in the last part of the article.

COVID-19 Vaccine-Related Beliefs and Behaviors Among Patients With and Survivors of Hematologic Malignancies

PURPOSE

Patients with and survivors of hematologic malignancies are particularly vulnerable to COVID-19 disease and complications. This study examined patients' vaccination attitudes and behaviors and their correlates.

METHODS

A two-wave survey was fielded in December 2020 and June 2021 among hematologic malignancy patients and survivors (N = 2,272). Demographic characteristics, intent to get vaccinated, vaccination status, attitudes toward vaccination, and level of trust in specific sources of information about COVID-19 vaccines were assessed. Descriptive statistics were calculated, and linear probability models were estimated to examine binary outcomes and their correlates.

RESULTS

In December 2020, before COVID-19 vaccines were available, 73% stated they were likely or very likely to get vaccinated if an FDA-approved vaccine became available; however, in June 2021 over 90% reported being vaccinated. Being younger, unmarried, trusting local faith leaders, and not having a bachelor's degree or more were negatively associated with getting vaccinated. Among those hesitant in December 2020, those who expressed a distrust of vaccines in general were least likely to get vaccinated. Being vaccinated in June 2021 was positively associated with the degree to which respondents trust their oncologist, federal agencies, and pharmaceutical companies. Oncologists and primary care physicians were reported as the most trusted sources for information about vaccines.

DISCUSSION

COVID-19 vaccine hesitancy remains a public policy concern even now, as additional boosters are recommended among vulnerable populations. Our findings suggest that patient trust in their treating physicians can play a critical role in promoting individual patient and public health goals.

From a voluntary vaccination policy to mandatory vaccination against COVID-19 in cancer patients: an empirical and interdisciplinary study in bioethics

BACKGROUND

At the start of 2021, oncologists lacked the necessary scientific knowledge to adapt their clinical practices optimally when faced with cancer patients refusing or reluctant to be vaccinated against COVID-19, despite the marked vulnerability of these patients to severe, and even fatal forms of this new viral infectious disease. Oncologists at Foch Hospital were confronted with this phenomenon, which was observed worldwide, in both the general population and the population of cancer patients.

METHODS

Between April and November 2021, the Ethics and Oncology Departments of Foch Hospital decided to investigate this subject, through an empirical and interdisciplinary study in bioethics. Our scientific objective was to try to identify and resolve the principal bio-ethical issues, with a view to improving clinical practices in oncology during future major pandemics of this kind, from a highly specific bio-ethical standpoint (= quality of life/survival). We used a mainly qualitative methodological approach based on questionnaires and interviews.

RESULTS

In April 2021, 29 cancer patients refused or were reluctant to be vaccinated (5.6%; 29/522). Seventeen of these patients said that making vaccination mandatory would have helped them to accept vaccination. In October 2021, only 10 cancer patients continued to maintain their refusal (1.9%; 10/522). One of the main reasons for the decrease in refusals was probably the introduction of the "pass sanitaire" (health pass) in July 2021, which rendered vaccination indispensable for many activities. However, even this was not sufficient to convince these 10 cancer patients.

CONCLUSION

We identified a key bio-ethical issue, which we then tried to resolve: vaccination policy. We characterized a major tension between "the recommendation of anti-COVID-19 vaccination" (a new clinical practice) and "free will" (a moral value), and the duty to "protect each other" (a moral standard). Mandatory vaccination, at least in France, could resolve this tension, with positive effects on quality of life (i.e. happiness), or survival, in cancer patients initially refusing or reluctant to be vaccinated, but only if collective and individual scales are clearly distinguished.

What determines health professionals' COVID-19 vaccine hesitancy? A nationwide study

INTRODUCTION

To contain the COVID-19 pandemic, higher vaccination rates are essential. However, as vaccine hesitancy is a reality, it is important to understand what drives health professionals to refuse getting vaccinated against COVID-19, who have been in the frontline of this pandemic since its beginning and may be key actors to improve vaccine coverage among their patients.

PURPOSE

This study aims to assess the factors associated with vaccine hesitancy (VH) among health professionals (physicians, nurses, pharmacists and dentists).

METHODS

A nationwide cross-sectional study was conducted through an online survey, with 890 Portuguese health professionals. A logistic regression analysis was used to determine the adjusted odds ratio (OR) of the independent variables (perceptions, knowledge and attitudes) per 1-point increase in the Likert scale and VH.

RESULTS

Complacency, communications, confidence and convenience were strongly associated with VH probability. Concerns about vaccines' efficacy (ORPhysicians  = 8.33, 95% CI: 4.51-15.36) and safety (ORNurses  = 11.07, 95% CI: 4.12-29.77) increase the risk of VH on all health professional groups. A reduction of VH probability is associated with higher risk perceptions of getting infected (1/ORNurses  = 2.76, 95% CI: 1.52-5.02) and suffering complications (1/ORNurses  = 33.72, 95% CI: 8.48-134.13), higher confidence in the effectiveness of COVID-19 vaccines (1/ORDentists  = 12.29, 95% CI: 2.91-51.89), risk perception of getting infected if vaccinated (1/ORPhysicians  = 14.92, 95% CI: 6.85-32.50), risk of suffering from complications after getting vaccinated, and higher trust levels on the information transmitted by competent authorities (1/ORDentists  = 17.76, 95% CI: 3.83-82.22).

CONCLUSIONS

To reduce COVID-19 VH, which appears to be highly influenced by perceptions, knowledge and attitudes, it is essential to promote interventions directed to transforming these potentially modifiable determinants.

Sociohistorical Analysis of Normative Standards of Masculinity in the Pandemic of COVID-19: Impacts on Men's Health/Mental Health

Objective

This study aims to analyze sociohistorically how the normative patterns of hegemonic masculinity produced impacts on men’s health/mental health in the context of the COVID-19 pandemic.

Methods

A qualitative study from a socio-historical perspective was conducted with 50 men based on an online survey. A semistructured form was applied. The data were analyzed by the Collective Subject Discourse method, interpreted in the light of the context of epidemic disease and hegemonic masculinity.

Results

The experience of the pandemic exposed the normative patterns of masculinities from the consummation of acts representative of the pandemic context, which incited men to deny the existence of COVID-19 disease and to delay the understanding and adoption of measures to protect and control COVID-19. As a repercussion, men presented conflicts in the regulation of emotions; presented emotional suppression; were more reactive; felt threatened regarding the loss of the role of family provider, virility; and revealed a sense of invulnerability, added to the weakening of self-care.

Conclusion

The discourse revealed that the men’s behaviors are consistent with the characteristics of hegemonic masculinity, but express signs of recognition that this behavior causes harm to themselves and their health.

What Lies Behind Substantial Differences in COVID-19 Vaccination Rates Between EU Member States?

Background

Despite the billions of doses at disposal, less than three-quarters of EU citizens received a COVID-19 vaccine by the end of 2021. The situation is particularly worrying in transition societies, which experience much stronger opposition to vaccination compared to their Western counterparts. To understand whether and to what extent this has to do with the socialist legacy, in this paper we explore wider economic, political, and cultural determinants of the COVID-19 vaccine uptake in the EU.

Methods

Data from Flash Eurobarometer 494 conducted in May 2021 were used to model the attitudes of EU citizens toward COVID-19 vaccination. Based on their views and intentions, each of 26,106 survey participants was allocated into one of the following categories: (1) already vaccinated/plan to get vaccinated; (2) indecisive; (3) refuse vaccination. Multilevel multinomial logit was employed to understand what underlies the reasoning of each group.

Results

The survey revealed that 13.4% of Europeans planned to delay vaccination against COVID-19, while 11.2% did not intend to get vaccinated. Although numerous demographic and socio-economic factors jointly shape their viewpoints, it is trust (in the authorities, science, peers, and online social networks above all) that strongly dominates citizens' reasoning. Given that most transition societies are witnessing the pandemic of distrust at various levels, this seemingly unrelated feature appears to be vital in explaining why newer member states record lower vaccination rates. Education was also found to play a pivotal role, which is reflected in an individual's ability to critically assess information from various sources.

Conclusion

The study results clearly illustrate how long-lasting structural problems (specific for, but not confined to, transition countries) can manifest themselves in unforeseen circumstances if left unaddressed. It is hence of vital importance to learn the lesson and prevent similar issues in the future. Above all, this would require wide-ranging reforms aiming to repair the imperceptible psychological contract between citizens and the state authorities.

Impact of population mixing between vaccinated and unvaccinated subpopulations on infectious disease dynamics: implications for SARS-CoV-2 transmission

Background:

The speed of vaccine development has been a singular achievement during the COVID-19 pandemic, although uptake has not been universal. Vaccine opponents often frame their opposition in terms of the rights of the unvaccinated. We sought to explore the impact of mixing of vaccinated and unvaccinated populations on risk of SARS-CoV-2 infection among vaccinated people.

Methods:

We constructed a simple susceptible–infectious–recovered compartmental model of a respiratory infectious disease with 2 connected subpopulations: people who were vaccinated and those who were unvaccinated. We simulated a spectrum of patterns of mixing between vaccinated and unvaccinated groups that ranged from random mixing to complete like-with-like mixing (complete assortativity), in which people have contact exclusively with others with the same vaccination status. We evaluated the dynamics of an epidemic within each subgroup and in the population as a whole.

Results:

We found that the risk of infection was markedly higher among unvaccinated people than among vaccinated people under all mixing assumptions. The contact-adjusted contribution of unvaccinated people to infection risk was disproportionate, with unvaccinated people contributing to infections among those who were vaccinated at a rate higher than would have been expected based on contact numbers alone. We found that as like-with-like mixing increased, attack rates among vaccinated people decreased from 15% to 10% (and increased from 62% to 79% among unvaccinated people), but the contact-adjusted contribution to risk among vaccinated people derived from contact with unvaccinated people increased.

Interpretation:

Although risk associated with avoiding vaccination during a virulent pandemic accrues chiefly to people who are unvaccinated, their choices affect risk of viral infection among those who are vaccinated in a manner that is disproportionate to the portion of unvaccinated people in the population.

Risk-Perception Change Associated with COVID-19 Vaccine's Side Effects: The Role of Individual Differences

The COVID-19 vaccine appears to be a crucial requirement to fight the pandemic. However, a part of the population possesses negative attitudes towards the vaccine. The spread of conspiracy theories and contradictory information about the pandemic have altered the population's perception of risk. The risk-perception of the vaccine's side effects may be affected by individual differences. The complex relationship between risk-perception and individual differences is relevant when people have to make decisions based on ambiguous and constantly changing information, as in the early phases of the Italian vaccination campaign. The present study aimed at measuring the effect of individual differences in risk-perception associated with the COVID-19 vaccine's side effects in a context characterized by information ambiguity. An online survey was conducted to classify a sample of Italian pro-vaccine people into cognitive/behavioral style groups. Furthermore, changes in vaccine risk-perception after inconsistent communications regarding the vaccine's side effects were compared between groups. The results showed that "analytical" individuals did not change their perception regarding the probability of vaccine side effects but changed their perception regarding the severity of side effects; "open" and "polarized" individuals neither changed their perception regarding the probability nor of the severity of side effects, showing a different kind of information processing, which could interfere with an informed decision-making process.

Psychological Distress in Men during the COVID-19 Pandemic in Brazil: The Role of the Sociodemographic Variables, Uncertainty, and Social Support

Objective: To analyze the relationships between sociodemographic variables, intolerance to uncertainty (INT), social support, and psychological distress (i.e., indicators of Common Mental Disorders (CMDs) and perceived stress (PS)) in Brazilian men during the COVID-19 pandemic. Methods: A cross-sectional study with national coverage, of the web survey type, and conducted with 1006 Brazilian men during the period of social circulation restriction imposed by the health authorities in Brazil for suppression of the coronavirus and control of the pandemic. Structural equation modeling analysis was performed. Results: Statistically significant direct effects of race/skin color (λ = 0.268; p-value < 0.001), socioeconomic status (SES) (λ = 0.306; p-value < 0.001), household composition (λ = 0.281; p-value < 0.001), PS (λ = 0.513; p-value < 0.001), and INT (λ = 0.421; p-value < 0.001) were evidenced in the occurrence of CMDs. Black-skinned men with higher SES, living alone, and with higher PS and INT levels presented higher prevalence values of CMDs. Conclusions: High levels of PS and INT were the factors that presented the strongest associations with the occurrence of CMDs among the men. It is necessary to implement actions to reduce the stress-generating sources as well as to promote an increase in resilience and the development of intrinsic reinforcements to deal with uncertain threats.