Trends in COVID-19 vaccination intent from pre- to post-COVID-19 vaccine distribution and their associations with the 5C psychological antecedents of vaccination by sex and age in Japan

Understanding COVID-19 Vaccine Hesitancy among the General Population in Japan from Public Health Ethical Perspectives: Findings from a Narrative Review

Japan has been reported as a country with high levels of vaccine hesitancy. However, a lack of comprehensive reviews studying factors for vaccine hesitancy for the COVID-19 vaccines in the Japanese context from the perspective of ethical controversy exists. Using a narrative review method, we reviewed factors associated with vaccine hesitancy to the COVID-19 vaccines and examined issues related to ethical controversy among the Japanese population. Factors associated with vaccine hesitancy include concerns about vaccine safety, suspicion of vaccine inefficacy, mistrust of the government, and low perceived threat. Factors associated with vaccine acceptance include environmental factors, factors related to Japanese cultural values, including collectivism and social norms, and positive attitudes toward information provided by authorities. Unique backgrounds in Japan are historical events such as the anti-HPV vaccine campaigns, the accessible medical system fostering high expectations of zero risk, and cultural factors of caring social norms influencing vaccine acceptance. Ethical controversies arise from preferences and practices at the individual or national level around individual rights versus public health benefits. Healthcare professionals and public health experts should continue dialoguing with the critical mass, practitioners, and policymakers, considering the ethical dilemmas surrounding individual rights and public health benefits. Insights obtained from this study indicate the need to develop tailored strategies to enhance vaccine acceptance while respecting individual autonomy within the Japanese context.

Vaccination decision-making among mothers of children 0-12 months old in Nigeria: A qualitative study

The contribution of vaccination to global health, especially in low-middle-income countries is one of the achievements in global governance of modern medicine, averting 2-3 million child deaths annually. However, in Nigeria, vaccine-preventable-diseases still account for one-in-eight child deaths before their fifth-year birthday. Nigeria is one of the ten countries where 4.3 million children under five are without complete immunization. Therefore, the goal of this contribution is to shed light on the reasons to set a foundation for future interventions. To conduct focus groups, a simplified quota sampling approach was used to select mothers of children 0-12 months old in four geographical clusters of Nigeria. An interview guide developed from the 5C psychological antecedence model was used (assessing confidence, complacency, calculation, constraints, collective responsibility); two concepts were added that had proved meaningful in previous work (religion and masculinity). The data were analyzed using a meta-aggregation approach. The sample was relatively positive toward vaccination. Still, mothers reported low trust in vaccine safety and the healthcare system (confidence). Yet, they had great interest in seeking additional information (calculation), difficulties in prioritizing vaccination over other equally competing priorities (constraints) and were aware that vaccination translates into overall community wellbeing (collective responsibility). They had a bias toward God as ultimate giver of good health (religion) and their husbands played a dominant role in vaccination decision-making (masculinity). Mothers perceived their children vulnerable to disease outbreaks, hence, motivated vaccination (complacency). The study provided a useful qualitative tool for understanding mothers' vaccination decision-making in low resources settings.

Association of vaccine intention against COVID-19 using the 5C Scale and its constructs: a Pima County, Arizona cross-sectional survey

Background

Vaccine hesitancy has been ranked as one of the top 10 threats to global health by the World Health Organization. The 5C model (Confidence, Calculation of risk, Complacency, Collective Responsibility, and Constraints) and an accompanying tool to measure vaccine hesitancy, summarize several significant explanatory variables, and move beyond the most common explanatory variable, Confidence.

Methods

From January to May 2021, we administered a cross-sectional survey among adults in Pima County, Arizona in collaboration with the local health department to assess psychological antecedents to (i.e., psychological factors that lead to) COVID-19 vaccination using the 5C Scale. Participants were recruited virtually for the survey using multiple recruitment methods. Unadjusted and adjusted hierarchical ordinal logistic regressions were conducted to determine if the 5C variables had an association with intention to vaccinate (or intent to vaccinate) against COVID-19.

Results

Of the 1,823 participants who responded to the survey, 924 (76%) were included in the final analyses. Respondents were White (71%), non-Hispanic (59%), Female (68%), Liberal (37%) and Married (46%). The average age of the participants was 43.9 (±1.3) years. Based on the 5C Scale, Confidence (adjOR:3.64, CI [3.08-4.29]), Collective Responsibility (adjOR:1.94, CI [1.57-2.39]) and Complacency (adjOR:0.64, CI [0.51-0.80]) were significantly associated with intention to vaccinate against COVID-19.

Conclusion

Three of the five 5C variables were associated with the intention to vaccinate, two positively and one negatively. A limitation of the study was that the sample was not weighted to be representative of Pima County. Future research should focus on determining which interventions can bolster Confidence and Collective Responsibility attitudes in communities, while dampening Complacency, to better promote vaccine uptake.

Psychological antecedents of vaccine inequity: keys to improve the rates of vaccination

BACKGROUND

The World Health Organization (WHO) stresses the importance of worldwide vaccine coverage of coronavirus-19 (COVID-19) vaccination. This study fills a critical gap in the literature by providing empirical evidence on the factors influencing COVID-19 vaccine hesitancy and inequity in the Middle East and North Africa (MENA) region. This study investigated the determinants of psychological antecedents and other factors behind COVID-19 vaccination and their role in vaccine coverage in MENA.

METHODS

An anonymous online cross-sectional survey was conducted in 11 MENA countries (Egypt, Sudan, Kuwait, Saudi Arabia, Morocco, Iraq, Yemen, Lebanon, Libya, Afghanistan, and Pakistan). The minimum required sample size from each country was 307, which was increased to 330 to accommodate a non-response rate of 7%. A multilevel logistic regression model was used to capture the clustering of observations in each country and estimate the explanatory variables' effects on each item of the 5C components of the psychological antecedents scale namely (confidence, constraints, complacency, calculation, and collective responsibility).

RESULTS

The total number of respondents was 3630, 40.5% of them were between the ages of 18 and 25 years, 61.1% were females, 54.0% completed university education, 55.8% were unmarried, 19.5% had chronic diseases, 43.7% reported a previous COVID-19 and 42.4% had relatives who died from COVID-19. Much of the variation in the log of the odds in each item of the 5Cs was due to heterogeneity between different countries (intraclass correlation > 0.05). Therefore, this variability confirms the various effects of psychological antecedents on vaccination coverage, stimulating vaccination inequity among them. Increasing confidence in vaccines and collective responsibility towards relatives and the community is related to increasing acceptance of the COVID-19 vaccine. The reduction in complacency, calculations, and constraints was found to be associated with acceptance of the COVID-19 vaccine.

CONCLUSIONS

This study is novel in shedding light on the importance of psychological determinants as hidden causes of vaccine inequities by using a multilevel logistic regression model for COVID-19 vaccination intention. The findings suggest that targeted interventions addressing socio-demographic factors, psychological antecedents, and accessibility barriers are essential to mitigate vaccine inequity and improve vaccination rates.

Seasonal Influenza Vaccine Literacy and Hesitancy of Elderly Czechs: An Analysis Using the 5C Model of Psychological Antecedents

Objectives

Seasonal influenza vaccination rates among the elderly in the Czech Republic are alarmingly low, making it one of the least vaccinated countries in Europe. This study explored the role of vaccine literacy and insurance coverage on vaccination status.

Methods

An analytical cross-sectional study was conducted in Summer 2023 using a self-administered questionnaire covering vaccine literacy (functional, interactive, and critical skills), negative perceptions towards influenza vaccination, and the 5C model (confidence, complacency, constraints, calculation, and collective responsibility). Individuals aged 55 and older were included in the study. Mediation analyses assessed the indirect effects of insurance coverage on vaccination status.

Results

Significant differences were noted in vaccination rates based on insurance coverage, chronic diseases, regular medication use, and previous COVID-19 and pneumococcal vaccinations. Vaccine literacy, especially interactive and critical skills, was higher among vaccinated individuals. Confidence and collective responsibility were significant promoters, while complacency and constraints were barriers to vaccination. Mediation analyses indicated that negative perceptions, confidence, and collective responsibility significantly mediated the relationship between insurance coverage and vaccination status.

Conclusion

Enhancing vaccine literacy and addressing psychological antecedents are crucial for improving influenza vaccination rates among the elderly. Policy measures should include improving vaccine literacy, building public confidence, and addressing negative perceptions.

Predictive factors of coronavirus disease (COVID-19) vaccination series completion: a one-year longitudinal web-based observational study in Japan

Introduction

Addresing vaccine hesitancy is considered an important goal in management of the COVID-19 pandemic. We sought to understand what factors influenced people, especially those initially hesitant, to receive two or more vaccine doses within a year of the vaccine's release.

Methods

We conducted longitudinal Web-based observational studies of 3,870 individuals. The surveys were conducted at four different time points: January 2021, June 2021, September 2021, and December 2021. In the baseline survey (January 2021), we assessed vaccination intention (i.e., "strongly agree" or "agree" [acceptance], "neutral" [not sure], and "disagree" or "strongly disagree" [hesitance]), and assumptions about coronavirus disease (COVID-19), COVID-19 vaccine, COVID-19-related health preventive behavior, and COVID-19 vaccine reliability. In subsequent surveys (December 2021), we assessed vaccination completion (i.e., ≥2 vaccinations). To investigate the relationship between predictors of COVID-19 vaccination completion, a multivariable logistic regression model was applied. Adjusted odds ratios (AORs) and 95% confidence intervals (CIs) were calculated while adjusting for gender, age, marital status, presence of children, household income category, and presence of diseases under treatment. In a stratified analysis, predictors were determined based on vaccination intention.

Results

Approximately 96, 87, and 72% of those who demonstrated acceptance, were not sure, or hesitated had been vaccinated after 1 year, respectively. Overall, significant factors associated with COVID-19 vaccine compliance included the influence of others close to the index participant (social norms) (AOR, 1.80; 95% CI, 1.56-2.08; p < 0.001), vaccine confidence (AOR, 1.39; 95% CI, 1.18-1.64; p < 0.001) and structural constraints (no time, inconvenient location of medical institutions, and other related factors) (AOR, 0.80; 95% CI, 0.70-0.91; p = 0.001). In the group of individuals classified as hesitant, significant factors associated with COVID-19 vaccine compliance included social norms (AOR, 2.43; 95% CI, 1.83-3.22; p < 0.001), confidence (AOR, 1.44; 95% CI, 1.10-1.88; p = 0.008), and knowledge (AOR, 0.69; 95% CI, 0.53-0.88; p = 0.003).

Discussion

We found that dissemination of accurate information about vaccines and a reduction in structural barriers to the extent possible enhanced vaccination rates. Once the need for vaccination becomes widespread, it becomes a social norm, and further improvements in these rates can then be anticipated. Our findings may help enhance vaccine uptake in the future.

Can delay discounting predict vaccine hesitancy 4-years later? A study among US young adults

Despite being a major threat to health, vaccine hesitancy (i.e., refusal or reluctance to vaccinate despite vaccine availability) is on the rise. Using a longitudinal cohort of young adults (N = 1260) from Los Angeles County, California we investigated the neurobehavioral mechanisms underlying COVID-19 vaccine hesitancy. Data were collected at two time points: during adolescence (12th grade; fall 2016; average age = 16.96 (±0.42)) and during young adulthood (spring 2021; average age = 21.33 (±0.49)). Main outcomes and measures were delay discounting (DD; fall 2016) and tendency to act rashly when experiencing positive and negative emotions (UPPS-P; fall 2016); self-reported vaccine hesitancy and vaccine beliefs/knowledge (spring 2021). A principal components analysis determined four COVID-19 vaccine beliefs/knowledge themes: Collective Responsibility, Confidence and Risk Calculation, Complacency, and Convenience. Significant relationships were found between themes, COVID-19 vaccine hesitancy, and DD. Collective Responsibility (β = -1.158[-1.213,-1.102]) and Convenience (β = -0.132[-0.185,-0.078]) scores were negatively associated, while Confidence and Risk Calculation (β = 0.283[0.230,0.337]) and Complacency (β = 0.412[0.358,0.466]) scores were positively associated with COVID-19 vaccine hesitancy. Additionally, Collective Responsibility (β = -0.060[-0.101,-0.018]) was negatively associated, and Complacency (β = -0.063[0.021,0.105]) was positively associated with DD from fall 2016. Mediation analysis revealed immediacy bias during adolescence, measured by DD, predicted vaccine hesitancy 4 years later while being mediated by two types of vaccine beliefs/knowledge: Collective Responsibility (β = 0.069[0.022,0.116]) and Complacency (β = 0.026[0.008,0.044]). These findings provide a further understanding of individual vaccine-related decision-making among young adults and inform public health messaging to increase vaccination acceptance.

Factors associated with COVID-19 vaccination hesitancy in South Korea: A cross-sectional study

Vaccination against COVID-19 has been promoted as a way to protect oneself and others from infection. To ensure the comprehensive acceptance of COVID-19 vaccines, the factors that affect COVID-19 vaccination hesitancy should be examined. This study aimed to identify the factors that affect COVID-19 vaccination hesitancy among Korean adults, focusing on COVID-19 knowledge and attitudes toward vaccination. This was a cross-sectional study conducted with 2286 Korean adults aged 20-64 years. Demographic characteristics, knowledge regarding COVID-19, and attitudes toward vaccination were assessed. A generalized linear model with Poisson regression was used to identify factors associated with COVID-19 vaccination hesitancy. Approximately 67% of the COVID-19 knowledge-related questions were correctly answered. A neutral attitude toward vaccination and relatively low vaccination hesitancy were found. COVID-19 vaccination hesitancy was affected by individuals' attitudes toward vaccination, as well as their gender and age, but not by their knowledge. Interventions or policies considering gender and age could be helpful in reducing COVID-19 vaccination hesitancy. Strategies to disseminate more accurate and novel information related to the COVID-19 vaccines should be implemented.

Critical interventions for demand generation in Zambia, Nepal, and Senegal with regards to the 5C psychological antecedents of vaccination

Introduction

Childhood vaccination is an effective intervention for lowering the burden of infectious disease. Vaccine coverage has increased globally, but vaccine hesitancy and refusal threatens these gains. The 5C psychological antecedents of vaccination ("5C") provides a validated measure of "vaccine hesitancy or confidence" to assess individual thoughts and behaviors behind vaccination. We investigated population-level factors that contributed to high and sustained vaccination coverage in Zambia, Nepal, and Senegal, and alignment with the 5Cs.

Methods

Data was collected in the larger Exemplars in Vaccine Delivery study, from focus group discussions (FDGs) and key informant interviews (KIIs) at the national, regional, district, health facility, and community levels of health systems in Zambia, Nepal, and Senegal. We assessed the demand environment, as relayed by participants, and identified interventions reported as successful for demand generation, then retroactively aligned the interventions with the 5C constructs.

Results

Demand was positively correlated with high confidence and collective responsibility. Psychological constraints sometimes impacted demand. Physical constraints created barriers in some communities, particularly difficult to access (i.e., mountainous). Occasionally, physical constraints did not affect vaccination behavior - parents believed the benefits of vaccination worth pursuing. Factors negatively correlated with demand and intent, complacency and calculation, had limited impact. Critical interventions were: targeted and tailored health education activities (media partnerships, school outreach); community engagement; community ownership; and community involvement (community health workers, leaders, religious figures).

Conclusion

We found similar interventions used to generate demand, with strategies aligned with the 5C constructs. Categorizing interventions by drivers of demand may help strategic planning and the division of resources; decision makers may choose to implement our suggested interventions. Assessing the 5Cs allows decision-makers to operationalize demand generation into concrete interventions and policies, and determine the individual impact of these constructs on the population and focus efforts on interventions tailored to a specific need.

COVID-19 vaccination intention among nursing, medical, and dental students: A systematic review and meta-regression analysis

The introduction of the COVID-19 vaccine amidst the pandemic has heralded a paradigm shift. Healthcare students in nursing, medicine, and dentistry must have positive attitudes owing to their future role in vaccine recommendations to the public and patients. This meta-regression analysis assessed the differences in COVID-19 vaccination intention (VI) of nursing, medical, and dental students. Medline/PubMed, EMBASE, CINAHL, Cochrane Library, and Korean MBASE were searched for eligible studies. Quality was assessed by the Joanna Briggs Institute's quality appraisal. Forty-one studies were included in the final analysis, and the estimation of pooled prevalence (68%) and relevant factors were assessed. Dental students were found to have the lowest VI (57%), which significantly (p = .018) differed from that of nursing students (64%). Countries in South-East Asia and those with high income levels were found to have high VI. Therefore, global vaccine programs for healthcare students should be prepared considering their geographical and economic status.

Determinants of COVID-19 Vaccine Acceptability among Healthcare Workers in Kenya-A Mixed Methods Analysis

Healthcare workers (HCWs) were a priority group for COVID-19 vaccination. Adopting the World Health Organization's 3C and the expanded 5C vaccine hesitancy models, we assessed the factors associated with COVID-19 vaccine acceptability among HCWs in Kenya. In a mixed methods study, respondents were from eight selected counties across the country. An online survey (n = 746), key informant interviews (n = 18) and focus group discussions (n = 3) were conducted. The data were analyzed concurrently. Quantitative data showed that all the 3C antecedents were strong predictors of vaccine acceptability. The association of vaccine acceptability was strongest with convenience (aOR 20.13, 95% CI 9.01-44.96), then complacency (aOR 10.15, 95% CI 4.63-22.21) and confidence (aOR 6.37, 95% CI 2.90-14.02). Marital status was a significant independent factor associated with vaccine acceptability (aOR 2.70, 95% CI 1.20-6.08). Qualitatively, convenience presented as the no-cost availability of vaccines at the health facilities, whereas non-complacency manifested from the first-hand observed experience of COVID cases, and the need to protect oneself and family members. Confidence was mainly attributed to increased knowledge, resulting from multiple training sessions and trust in regulatory authorities. Other social factors including workplace pressure, religion and misinformation had a role in influencing HCW vaccination decisions. In the background of a pandemic, the 3C model is a strong predictor of vaccine acceptability, and making the vaccines easily available and convenient to HCWs significantly impacts their uptake.

Does the Integration of Migrants in the Host Society Raise COVID-19 Vaccine Acceptance? Evidence From a Nationwide Survey in Japan

Research indicates that integration contributes to maintaining health among migrants, yet little is known about the association between integration and vaccination acceptance. This study aimed to explore COVID-19 vaccine intention and acceptance, and the association between integration and vaccine hesitancy among migrants in Japan. We conducted an internet survey among migrants in Japan from October 5 to October 14, 2021. Among 1,455 participants, 11.6% reported hesitancy toward COVID-19 vaccination. We found that the overall integration and social integration were associated with the vaccination intention. Some commonly identified barriers (e.g., financial difficulties, language) were not related to COVID-19 vaccination acceptance among migrants in Japan. Highly integrated migrants were less likely to report vaccine hesitancy against COVID-19. To promote COVID-19 acceptance among migrants, customized intervention policies should focus on the migrants with a lower level of integration, especially those with little social connection with the locals.

The Role of Trust in COVID-19 Vaccine Acceptance: Considerations from a Systematic Review

The goal of this research was to provide an overview of the role of trust in determining COVID-19 vaccine acceptance. Trust proved to be a key issue in all the strategic phases of the pandemic, a decisive element for the success of the worldwide vaccination campaign. By introducing a comprehensive systematic review of the state-of-the-art (N = 43), we intend to shed light on the various forms of trust that have been considered and how these relate to citizens’ vaccine acceptance. The analysis shows that trust has been used extensively, with particular reference to the COVID-19 vaccine, governments, manufacturers, healthcare systems, and science. A more in-depth analysis has also allowed us to evaluate the role that these factors have had and the social phenomena in which they have been decisive. Most notably, we proved that, in the different contributions, trust in the COVID-19 vaccine has a strong correlation with vaccine acceptance (R = 0.78, p < 0.01). Overall, vaccine acceptance emerges as a complex phenomenon that needs to be understood through the strictly interlaced relations of trust in the various factors coming into play. Besides clarifying what happened in previous years, the considerations included in this work also represent an important and useful interpretative framework to help public institutions and the healthcare system in the future.

Models of determinants of COVID-19 vaccine hesitancy in non-pregnant and pregnant population: Review of current literature"

Vaccination has proven to be the most effective tool in controlling the COVID-19 pandemic. While pregnant individuals are considered to be a high-risk population and are more likely to experience adverse effects from COVID-19, vaccination rates among pregnant individuals are significantly lower than in the general population. The Health Belief Model (HBM), Theory of Planned Behavior (TPB), 3C model, 5C model, and 5A model have been used to assess vaccination hesitancy behaviors. In this paper, we review the use of each of these models to address vaccine hesitancy, with a focus on the pregnant population and the COVID-19 vaccine. The HBM, TPB, 3C model, and 5C model have demonstrated great versatility in their ability to evaluate, explain, and modify vaccine hesitancy and behavior. Up to date, the HBM and 3C models appear to be the most effective models to study and address vaccination hesitancy within the pregnant persons.

COVID-19 vaccine hesitancy and short-term and long-term intentions among unvaccinated young adults: a mixed-method approach

BACKGROUND

Only 63.8% of Americans who are 18-to-24-years-old have been fully vaccinated for COVID-19 as of June 1, 2022. The Grand Forks County, North Dakota is facing a similar challenge. As of June 2022, 47% of individuals in the 19-to-29-year-old age group are vaccinated. Focusing on unvaccinated individuals in their 20s, Study 1 aims to understand the ways in which receiving COVID-19 vaccines is construed using qualitative interviews; and Study 2 compares the predictors of short-term vaccination intention (i.e., next month) with those of long-term vaccination intention (i.e., three to 5 years) using an online survey.

METHODS

For Study 1, we conducted five focus groups and four in-depth interviews via Zoom with a total of 26 unvaccinated individuals in their 20s living in the Grand Forks County. Constant comparison process was used to categorize data into themes and to recognize characteristics of the identified themes. The aim was to develop themes and associated characteristics. For Study 2, we conducted an online survey with a convenience sample of 526 unvaccinated individuals. Logistic regression estimated odds ratios (OR) and 95% confidence intervals (CI) for associations between attitudes, perceptions, and beliefs in misinformation and short-term and long-term vaccination intentions, accounting for demographics and socioeconomic status.

RESULTS

In Study 1, two themes were identified: feelings of uncertainty sparked by profits and monetization and navigating the fear of the unknown. In Study 2, an increase in the confidence of COVID-19 vaccines showed significantly higher odds of short-term intention (OR = 2.658, 95%CI 1.770, 3.990) and long-term intention (OR = 1.568, 95% CI 1.105, 2.226). Believing in misinformation had significantly lower odds of short-term intention (OR = 0.712, 95%CI 0.513, 0.990), while more positive attitudes (OR = 1.439, 95% CI 1.024, 2.024), stronger preference in calculating the benefits of COVID-19 vaccines (OR = 2.108, 95% CI 1.541, 2.882), and greater perceived susceptibility (OR = 1.471, 95% CI 1.045, 2.070) to and severity of contracting COVID-19 (OR = 1.362, 95% CI 1.020, 1.820) were significantly associated with higher odds of long-term intention.

CONCLUSIONS

Short-term and long-term intentions were predicted differently. Instilling strong confidence in COVID-19 vaccines should increase both short-term and long-term intentions.

Factors associated with reversals of COVID-19 vaccination willingness: Results from two longitudinal, national surveys in Japan 2021-2022

BACKGROUND

Research characterizing changes of heart with respect to vaccine intention is scarce, and very little research considers those who were initially vaccine willing but became hesitant. Here, we sought to assess the factors related to reversals of vaccine willingness.

METHODS

We conducted a longitudinal, national survey on vaccination intention among Japanese adults aged 20 years or older, with the first questionnaire performed in February-March 2021 (N = 30,053) and the follow-up in February 2022 (N = 19,195, response rate 63.9%). The study population comprised those who reported vaccine willingness in the first survey, with the outcome variable being development of vaccine hesitancy at follow-up. We performed a regression analysis of vaccination status using sociodemographic, health-related, psychologic/attitudinal, and information-related variables as predictors. We used the sparse group minimax concave penalty (MCP) to select the optimum group of covariates for the logistic regression.

FINDINGS

Of 11,118 (57.9%) respondents who previously expressed interest in vaccination, 10,684 (96.1%) and 434 (3.9%) were in the vaccine willing and hesitant groups, respectively. Several covariates were found to significantly predict vaccine hesitancy, including marital status, influenza vaccine history, COVID-19 infection/testing history, engagement in COVID-19 preventive measures, perceived risks/benefits of the COVID-19 vaccine, and attitudes regarding vaccination policies and norms. The use of certain information sources was also associated with vaccine hesitancy.

INTERPRETATION

Sociodemographic, health-related, psychologic/attitudinal, and information-related variables predicted the development of vaccine hesitancy among those with prior willingness. Most of these predictors were also associated with vaccination status.

FUNDING

The present work was supported in part by a grant from the Kanagawa Prefectural Government of Japan and by AIST government subsidies.

Psychological determinants of COVID-19 vaccine acceptance among urban slum dwellers of Bangladesh

Introduction

Coronavirus disease 2019 (COVID-19) vaccination has emerged as a promising approach to counter the harmful impacts of the pandemic. Understanding the psychological components that may impact an individual's attitude toward COVID-19 vaccination is crucial for generating evidence-based ways to minimize vaccine hesitancy. This study determined the psychological antecedents regarding vaccine acceptance among urban slum people of Bangladesh.

Methods

From 5 July to 5 August 5, 2021, a face-to-face survey was conducted in the urban slum of two large cities in Bangladesh. The questionnaire considered socio-demographics, health-related characteristics, psychological determinants, sources of information, and conspiracy beliefs regarding COVID-19. The 5C sub-scales were used to assess psychological antecedents. Five stepwise binary logistic regression models evaluated significant predictors for confidence, complacency, calculation, constraints, and collective responsibility. Multinomial logistic regression was used to determine the relationship between psychological antecedents and vaccine acceptability.

Results

The study revealed that the slum residents with a high level of confident (89.94%), complacent (72.73%), having constraints (82.31%), calculative (84.80%), and responsible (93.30%) showed a higher vaccine acceptance rate. Higher vaccine acceptance was related to the believer in natural-made origin (85.96%) and those who rejected anti-vaccination (88.44%). The information acquired from newspapers differed significantly (p < 0.05), though TV or radio was the most common primary information source about COVID-19 vaccines (74.75%). The regression result revealed that marital status, education, family income, and perceived health condition were significantly associated with the 5C domains. Two psychological antecedents including complacency (OR = 3.97; p < 0.001) and collective responsibility (OR = 0.23; p < 0.001) were significantly associated with vaccine acceptance.

Conclusions

Different predictors significantly affect psychological antecedents related to COVID-19 vaccine uptake. Therefore, considering the factors, targeted actions based on the findings may help to lower vaccine reluctance and boost vaccination rates.

Development, validity, and reliability of the Japanese version of the 7C of vaccination readiness scale

BACKGROUND

The 7C of vaccination readiness scale measures the seven psychological components that structure people's vaccination readiness. We aimed to develop the Japanese version of this scale (7C scale Japanese version) and to assess its validity and reliability.

METHODS

The full and short versions of 7C scale Japanese were developed based on translation guidelines provided by the ISPOR Task Force. An Internet survey, including 709 participants, was performed to assess the scale's validity and reliability within a confirmatory factor analysis (CFA) framework (men: 38.8%, age range: 20-92 years). Invariance analysis using multiple-group CFA was conducted to test cross-cultural validity between participants in this study and those in the 7C original version study. McDonald's omega and intraclass correlation coefficient were calculated to evaluate internal consistency and test-retest reliability, respectively. To clarify the criterion validity, regression analysis, with previous COVID-19 vaccination status as the dependent variable, was performed to calculate pseudo R².

RESULTS

The 7C scale Japanese version exhibited good content validity, structural validity, configural invariance, and criterion validity. The results showed good internal consistency, and test-retest reliability, except for the "calculation" component.

CONCLUSIONS

7C scale Japanese version exhibited acceptable reliability and validity; however, "calculation" may be a less reliable subscale.

Trust in Science as a Possible Mediator between Different Antecedents and COVID-19 Booster Vaccination Intention: An Integration of Health Belief Model (HBM) and Theory of Planned Behavior (TPB)

As the literature highlights, many health behavior theories try to explain both social and psychological variables influencing an individual’s health behavior. This study integrates insights relative to the antecedents of getting vaccinated from health behavior theories, particularly including the health belief model (HBM), the theory of planned behavior (TPB), and the different socio-demographic factors. Furthermore, we considered the possible mechanism of impact of distrust in science on individuals’ hesitance and resistance to taking up SARS-CoV-2 vaccination in subjects living in Italy. A correlational study of 1095 subjects enrolled when the national vaccination campaign for the third dose was launched. A questionnaire was used to measure: Italian Risk Perception; subjective norm; trust in science, trust in the vaccine; fear of COVID-19; fear of the vaccine; perceived knowledge about SARS-CoV-2; booster vaccination intention. Principal results show that: (i) the positive relationship provided by HBM theory between perceptions of SARS-CoV-2 risk (vulnerability and severity) and intention to have the vaccine, through fear of COVID-19; (ii) the positive relationship between subjective norms and both trust in science and vaccination intention; (iii) that trust in science plays a crucial role in predicting vaccination intention. Finally, the results provided indications about a positive relationship between subjective norms and fear of COVID-19, and a full mediation role of trust in science in the relationships between determinants of both TPA and HBM, fear of COVID-19, and vaccination intention. In conclusion, an individual’s intention (not) to get vaccinated requires the consideration of a plethora of socio-psychological factors. However, overall, trust in science appears to be a key determinant of vaccination intention. Additional strategies promoting healthy behavior are needed.

The Relationship between Sources of COVID-19 Vaccine Information and Willingness to Be Vaccinated: An Internet-Based Cross-Sectional Study in Japan

Despite considerable interest in the Japanese population in receiving the vaccine for COVID-19 when it first became available, a sizable percentage of people remain unwilling or hesitant to be vaccinated. Concerns among both the vaccinated and the unwilling center on the vaccine’s efficacy and its safety. Thus, this study aimed to identify whether the willingness to receive COVID-19 vaccination is related to the sources of information people use to learn about the vaccine. A cross-sectional study was conducted on 800 participants registered in an Internet research panel across Japan who completed a questionnaire on their sources of information about the vaccine, demographics, and vaccination status. Vaccine willingness/hesitancy and refusal were set as dependent variables in the logistic regression analysis, with sources of vaccine information and other socio-demographic variables set as independent variables. The results of the analysis found that the information sources significantly associated with willingness to vaccinate were TV (AOR 2.44 vs. vaccine refusal/hesitation), summary websites of COVID-19 by non-experts (AOR 0.21, vs. vaccine refusal/hesitation), Internet video sites (AOR 0.33, vs. vaccine refusal/hesitation), and the personal websites of doctors (AOR 0.16, vs. vaccine refusal/hesitation). Given the likelihood of misinformation in non-traditional sources of information, it is important that health communications be accurate and persuasive.

COVID-19 vaccine acceptance and hesitancy among primary healthcare workers in Singapore

BACKGROUND

Factors affecting COVID-19 vaccine acceptance and hesitancy among primary healthcare workers (HCW) remain poorly understood. This study aims to identify factors associated with vaccine acceptance and hesitancy among HCW.

METHODS

A multi-centre online cross-sectional survey was performed across 6 primary care clinics from May to June 2021, after completion of staff vaccination exercise. Demographics, profession, years working in healthcare, residential status, presence of chronic medical conditions, self-perceived risk of acquiring COVID-19 and previous influenza vaccination were collected. HCW who accepted vaccine were then asked to rank their top 5 reasons for vaccine acceptance; HCW who were vaccine hesitant had to complete the 15-item 5C scale on psychological antecedents of vaccination.

RESULTS

Five hundred fifty seven out of 1182 eligible HCW responded (47.1%). Twenty nine were excluded due to contraindications. Among 528 respondents, vaccine acceptance rate was 94.9% (n = 501). There were no statistically significant differences in COVID-19 vaccine acceptance between sex, age, ethnicity, profession, number of years in healthcare, living alone, presence of chronic diseases, self-perceived risk or previous influenza vaccination. The top 3 reasons for COVID-19 vaccine acceptance ranked by 501 HCW were to protect their family and friends, protect themselves from COVID-19 and due to high risk of acquiring COVID-19 because of their jobs. HCW with suspected or confirmed COVID-19 exposure were 3.4 times more likely to rank 'high risk at work' as one of the top reasons for vaccine acceptance (χ2 = 41.9, p < 0.001, OR = 3.38, 95%C.I. 2.32-4.93). High mean scores of 'Calculation' (5.79) and low scores for 'Constraint' (2.85) for 5C components among vaccine hesitant HCW (n = 27) highlighted that accessibility was not a concern; HCW took time to weigh vaccine benefits and consequences.

CONCLUSION

COVID-19 vaccine hesitancy is a minute issue among Singapore primary HCW, having achieved close to 95% acceptance rate. COVID-19 exposure risk influences vaccine acceptance; time is required for HCW to weigh benefits against the risks. Future studies can focus on settings with higher hesitancy rates, and acceptance of booster vaccinations with the emergence of delta and omicron variants.

Analysis of People’s Attitude Toward COVID-19 Vaccine and Its Information Sources in Thailand

Introduction

Coronavirus disease 2019 (COVID-19) vaccine hesitancy has become a global problem. Therefore, we aimed to determine the relationship between the information sources on vaccines and the willingness of people to be vaccinated in Thailand.

Methods

A sample of 500 respondents was drawn from an Internet research panel, and a questionnaire survey was administered to evaluate respondents’ willingness to be vaccinated by sex, age group, educational background, occupation, and presence of chronic diseases, as well as their information sources on COVID-19 vaccines. Descriptive statistics and logistic regression analysis were employed to assess the relationship between vaccine hesitancy/refusal and other variables.

Results

Our results demonstrated that 90.2% of the participants were either willing to vaccinate or were already vaccinated. By contrast, 6.0% were hesitant and 3.8% did not want to be vaccinated. Females, people with education less than master’s/bachelor’s degree or high school, day laborers, housewives, and unemployed were significantly related to vaccine hesitation/refusal. Furthermore, they were less likely than the vaccine willingness group to use information resources from the Ministry of Health, public health centers, or medical associations.

Conclusions

As vaccine hesitancy and refusal ratio were found to be substantially lower than in a previous study for Thailand and other countries, public authorities should poll the public to identify vaccine-hesitant populations and their reasoning and provide appropriate information directly to the general public.

Parental perceptions and the 5C psychological antecedents of COVID-19 vaccination during the first month of omicron variant surge: A large-scale cross-sectional survey in Saudi Arabia

BACKGROUND

With the rapid surge of SARS-CoV-2 Omicron variant, we aimed to assess parents' perceptions of the COVID-19 vaccines and the psychological antecedents of vaccinations during the first month of the Omicron spread.

METHODS

A cross-sectional online survey in Saudi Arabia was conducted (December 20, 2021-January 7, 2022). Convenience sampling was used to invite participants through several social media platforms, including WhatsApp, Twitter, and email lists. We utilized the validated 5C Scale, which evaluates five psychological factors influencing vaccination intention and behavior: confidence, complacency, constraints, calculation, and collective responsibility.

RESULTS

Of the 1,340 respondents, 61.3% received two doses of the COVID-19 vaccine, while 35% received an additional booster dose. Fify four percentage were unwilling to vaccinate their children aged 5-11, and 57.2% were unwilling to give the additional booster vaccine to children aged 12-18. Respondents had higher scores on the construct of collective responsibility, followed by calculation, confidence, complacency, and finally constraints. Confidence in vaccines was associated with willingness to vaccinate children and positively correlated with collective responsibility (p < 0.010). Complacency about COVID-19 was associated with unwillingness to vaccinate older children (12-18 years) and with increased constraints and calculation scores (p < 0.010). While increasing constraints scores did not correlate with decreased willingness to vaccinate children (p = 0.140), they did correlate negatively with confidence and collective responsibility (p < 0.010).

CONCLUSIONS

The findings demonstrate the relationship between the five antecedents of vaccination, the importance of confidence in vaccines, and a sense of collective responsibility in parents' intention to vaccinate their children. Campaigns addressing constraints and collective responsibility could help influence the public's vaccination behavior.