Global state of education-related inequality in COVID-19 vaccine coverage, structural barriers, vaccine hesitancy, and vaccine refusal: findings from the Global COVID-19 Trends and Impact Survey

Social Vulnerability and Compliance With World Health Organization Advice on Protective Behaviors Against COVID-19 in African and Asia Pacific Countries: Factor Analysis to Develop a Social Vulnerability Index

BACKGROUND

COVID-19 protective behaviors are key interventions advised by the World Health Organization (WHO) to prevent COVID-19 transmission. However, achieving compliance with this advice is often challenging, particularly among socially vulnerable groups.

OBJECTIVE

We developed a social vulnerability index (SVI) to predict individuals' propensity to adhere to the WHO advice on protective behaviors against COVID-19 and identify changes in social vulnerability as Omicron evolved in African countries between January 2022 and August 2022 and Asia Pacific countries between August 2021 and June 2022.

METHODS

In African countries, baseline data were collected from 14 countries (n=15,375) during the first Omicron wave, and follow-up data were collected from 7 countries (n=7179) after the wave. In Asia Pacific countries, baseline data were collected from 14 countries (n=12,866) before the first Omicron wave, and follow-up data were collected from 9 countries (n=8737) after the wave. Countries' socioeconomic and health profiles were retrieved from relevant databases. To construct the SVI for each of the 4 data sets, variables associated with COVID-19 protective behaviors were included in a factor analysis using polychoric correlation with varimax rotation. Influential factors were adjusted for cardinality, summed, and min-max normalized from 0 to 1 (most to least vulnerable). Scores for compliance with the WHO advice were calculated using individuals' self-reported protective behaviors against COVID-19. Multiple linear regression analyses were used to assess the associations between the SVI and scores for compliance to WHO advice to validate the index.

RESULTS

In Africa, factors contributing to social vulnerability included literacy and media use, trust in health care workers and government, and country income and infrastructure. In Asia Pacific, social vulnerability was determined by literacy, country income and infrastructure, and population density. The index was associated with compliance with the WHO advice in both time points in African countries but only during the follow-up period in Asia Pacific countries. At baseline, the index values in African countries ranged from 0.00 to 0.31 in 13 countries, with 1 country having an index value of 1.00. The index values in Asia Pacific countries ranged from 0.00 to 0.23 in 12 countries, with 2 countries having index values of 0.79 and 1.00. During the follow-up phase, the index values decreased in 6 of 7 African countries and the 2 most vulnerable Asia Pacific countries. The index values of the least vulnerable countries remained unchanged in both regions.

CONCLUSIONS

In both regions, significant inequalities in social vulnerability to compliance with WHO advice were observed at baseline, and the gaps became larger after the first Omicron wave. Understanding the dimensions that influence social vulnerability to protective behaviors against COVID-19 may underpin targeted interventions to enhance compliance with WHO recommendations and mitigate the impact of future pandemics among vulnerable groups.

Vaccine Equity: Lessons Learned Exploring Facilitators and Barriers to COVID-19 Vaccination in Urban Black Communities

COVID-19 vaccines were developed at unparalleled speed, but racial disparities persist in vaccine uptake. This is a cross-sectional survey that was conducted in mid-2021 in ambulatory clinics across Brooklyn, New York. The objectives of the study were to assess: knowledge of COVID-19, healthcare communication and access, attitudes including trust in the process of vaccine development and mistrust due to racial discrimination, and to determine the relationship of the above to vaccine receipt. 58 respondents self-identified as Black non-Hispanic and completed the survey: the majority were women (79%), <50 years old (65%), employed (66%), and had annual household income <$75,000 (59%). The majority reported having some health insurance (97%) and a regular place of healthcare (95%). 60% of respondents reported COVID-19 vaccination receipt. A significant percentage of the vaccinated group compared to the unvaccinated group scored higher on knowledge questions (91% vs. 65%; p = 0.018), felt it was important that others in the community get vaccinated (89% vs. 65%, p = 0.04), and trusted vaccine safety (86% vs. 35%; p < 0.0001) and effectiveness (88% vs. 48%; p < 0.001). The unvaccinated group reported a lower annual household income of <$75,000 (72% vs. 50%; p = 0.0002) and also differed by employment status (p = 0.04). Majority in both groups agreed that racial discrimination interferes with healthcare (78%). In summary, unvaccinated Black non-Hispanic respondents report significant concerns about vaccine safety and efficacy and have greater mistrust in the vaccine development process. The relationship between racial discrimination, mistrust, and vaccine hesitancy needs further study in order to improve vaccine uptake in this population.

A Systematic Review of Factors Associated with COVID-19 Vaccine Uptake, Hesitancy, and Acceptability Among Adults with HIV: Implications for Integrating COVID-19 Immunization into HIV Care

The COVID-19 virus, once a public health emergency, is now endemic. Immunization remains an important measure for mitigating high levels of disease, morbidity, and mortality related to COVID-19 infection. People with HIV (PWH), in particular, benefit from COVID-19 vaccination because of increased risk for severe COVID-19 infection. However, previous data suggest vaccine hesitancy among this population. Given this context and the evolving epidemiology of COVID-19, this review examines factors associated with COVID-19 vaccine hesitancy, acceptability, and uptake among adults with HIV. Through a systematic search of electronic databases, we identified 56 peer-reviewed articles published between the years 2020 and 2023 that matched the objectives of our review out of a total of 797 screened citations. Among our final sample of articles, nearly all global regions were represented, and 61% of studies recruited only PWH. We identified eight categories of factors associated with COVID-19 vaccination outcomes, including HIV-specific factors (e.g., CD4 count), vaccine attitudes (e.g., vaccine confidence), factors related to the COVID-19 virus (e.g., concern about infection), factors specific to the COVID-19 vaccine (e.g., accessibility), social norms and peer factors (e.g., subjective norms), mental health (e.g., anxiety/depression) and other psychological factors (e.g., substance use), demographic characteristics (e.g., age), and health factors (e.g., vaccination history). Reflecting on these factors, we discuss populations in need of vaccine promotion, modifiable targets for intervention, and integrating immunization into HIV care. Public health efforts to promote COVID-19 immunization among PWH must include educational/informational, peer, and structural interventions and must now consider uptake of COVID-19 booster doses.

Global prevalence and correlates of mpox vaccine acceptance and uptake: a systematic review and meta-analysis

BACKGROUND

Vaccination has been recommended as one of the most potent ways of controlling the mpox (formerly, monkeypox) outbreak, particularly among high-risk groups. Here, we evaluated the prevalence of mpox vaccine acceptance and uptake globally.

METHODS

We searched multiple databases for peer-reviewed studies published in English from May 2022 to 25th November 2023 that evaluated mpox vaccine acceptance and/or uptake. We fit a random-effects model meta-analysis to calculate the pooled mpox vaccine acceptance and uptake rates, with their 95% confidence intervals (CI) across population outcomes. We performed subgroup analyses among the six World Health Organization (WHO) regions (Africa [AFR], Region of the Americas [AMR], South-East Asia Region [SEAR], European Region [EUR], Eastern Mediterranean Region [EMR], and the Western Pacific Region [WPR]), as well as among select population subgroups.

RESULTS

Of the 2531 studies screened, 61 studies, with a cumulative sample size of 263,857 participants from 87 countries were eligible for inclusion. The overall vaccine acceptance and uptake rates were 59.7% and 30.9% globally. Acceptance and uptake rates among the LGBTQI+ community were 73.6% vs 39.8% globally, 60.9% vs. 37.1% in AMR, 80.9% vs. 50.0% in EUR, and 75.2% vs. 33.5% in WPR. Among PLHIV, vaccine acceptance and uptake rates were 66.4% vs. 35.7% globally, 64.0% vs. 33.9% in AMR, 65.1% vs. 27.0% in EUR, and 69.5% vs. 46.6% in WPR. Among healthcare workers, vaccination intention was 51.0% globally.

CONCLUSIONS

Tailored interventions are needed to bolster confidence in the mpox vaccine, maximize vaccine uptake, and increase vaccine access to close the gaps between acceptance and uptake especially among key populations residing in regions with low rates of acceptance and uptake.

Factors influencing COVID-19 vaccine uptake among Latinos: A cross-sectional study

Vaccination against COVID-19 can prevent severe illness and reduce hospitalizations and deaths. Understanding and addressing determinants contributing to vaccine uptake among high-risk groups, such as Latinos, are pivotal in ensuring equitable vaccine distribution, promoting health equity, and fostering community engagement to bridge the gap in vaccine acceptance and ultimately enhance public health. This study aimed to examine factors influencing vaccine uptake among Latinos. We conducted a cross-sectional study using an online platform (n = 242). The survey was administered using a multimodal approach. Strategies for recruitment included community outreach, social media, and targeting community networks serving Latinos. Descriptive statistics, chi-square, and multivariable analysis were performed. Overall, 81.4% of respondents had received at least one dose of the COVID-19 vaccine, with 77.0% recommending it and 70.6% believing it to be safe, 66.7% believing in its efficacy, 62.3% able to find trustful information in Spanish or Portuguese, and almost 40% who relied on health organizations as their primary resource for COVID-19 vaccine information. Factors significantly associated with vaccine uptake included higher education level (p<0.001), English level (p = 0.023), living in an urban area (p = 0.048), having insurance (p<0.001), and having a healthcare provider (p = 0.007). Furthermore, belief in vaccine safety and efficacy, trust in public health authorities, concerns about COVID-19, the ability to determine true/false vaccine information during the pandemic, and the availability of trustworthy information in Spanish/Portuguese had statistically significant associations (p<0.05) with COVID-19 vaccine uptake. COVID-19 vaccine uptake differed based on sociodemographic and other modifiable factors. Our findings emphasize the importance of implementing targeted interventions and culturally sensitive communication strategies to improve vaccination uptake among the Latino community in the United States.

Understanding the determinants of vaccine hesitancy in the United States: A comparison of social surveys and social media

The COVID-19 pandemic prompted governments worldwide to implement a range of containment measures, including mass gathering restrictions, social distancing, and school closures. Despite these efforts, vaccines continue to be the safest and most effective means of combating such viruses. Yet, vaccine hesitancy persists, posing a significant public health concern, particularly with the emergence of new COVID-19 variants. To effectively address this issue, timely data is crucial for understanding the various factors contributing to vaccine hesitancy. While previous research has largely relied on traditional surveys for this information, recent sources of data, such as social media, have gained attention. However, the potential of social media data as a reliable proxy for information on population hesitancy, especially when compared with survey data, remains underexplored. This paper aims to bridge this gap. Our approach uses social, demographic, and economic data to predict vaccine hesitancy levels in the ten most populous US metropolitan areas. We employ machine learning algorithms to compare a set of baseline models that contain only these variables with models that incorporate survey data and social media data separately. Our results show that XGBoost algorithm consistently outperforms Random Forest and Linear Regression, with marginal differences between Random Forest and XGBoost. This was especially the case with models that incorporate survey or social media data, thus highlighting the promise of the latter data as a complementary information source. Results also reveal variations in influential variables across the five hesitancy classes, such as age, ethnicity, occupation, and political inclination. Further, the application of models to different MSAs yields mixed results, emphasizing the uniqueness of communities and the need for complementary data approaches. In summary, this study underscores social media data's potential for understanding vaccine hesitancy, emphasizes the importance of tailoring interventions to specific communities, and suggests the value of combining different data sources.

Assessment of the impact of the vaccine pass policy on COVID-19 vaccine hesitancy and uptake among Chinese adults in Hong Kong

BACKGROUND

Recognising the importance of attaining high vaccine coverage to mitigate the COVID-19 impact, a Vaccine Pass scheme was implemented during and after the first large Omicron wave with high mortality in older ages in Hong Kong in early 2022 requiring three doses by June 2022. We did not identify any studies evaluating the policy impact of vaccination mandates with vaccine uptake over whole policy period of time in a Chinese population. We aim to evaluate the impact of the Vaccine Pass policy on COVID-19 vaccine uptake in adults in a Chinese population in Hong Kong.

METHODS

We analysed patterns in vaccine uptake and hesitancy using local data from population vaccine registry and 32 cross-sectional telephone surveys conducted from October 2021 to December 2022. The association of Vaccine Pass phases with vaccine uptake was examined using logistic regression analyses, taking into account covariates including self-risk perception, perceived self-efficacy in preventing COVID-19 and trust in government in pandemic control as well as physical distancing measures and demographics.

RESULTS

The uptake of primary series and third doses was positively significantly associated with the successive stages of Vaccine Pass implementation (adjusted odds ratios ranged from 2.41 to 7.81). Other statistically significant drivers of uptake included age group, chronic condition, higher perceived personal susceptibility to COVID-19, higher trust in government, and higher educational attainment.

CONCLUSION

Vaccine uptake in older adults was observed to have increased by a greater extent after the policy annoucement and implementation, under the contextual changes during and after a large Omicron wave with high mortality in Hong Kong in early 2022. Since the policy withdrawal the uptake of further booster doses has been very low in all ages. We suggest that improving voluntary booster uptake in older adults should be prioritized.

Sharing lessons learned from COVID-19 vaccine introductions: a global community forum for countries

To optimize the efficient introduction and deployment of COVID-19 vaccines across the globe during the COVID-19 pandemic, in April 2021 WHO launched a new process and tools for countries to rapidly review the early phase of countries' COVID-19 vaccine introduction. This methodology is called the COVID-19 vaccination intra-action review, also known as mini COVID-19 vaccine post-introduction evaluation (mini-cPIE). As of November 2022, 46 mini-cPIEs had been conducted. In collaboration with Project ECHO, WHO convened and facilitated real-time experience sharing and peer-learning among countries following their mini-cPIEs through a virtual global real-time learning forum. This five-session clinic series was attended by 736 participants from 129 countries. Based on post-session feedback surveys, when asked about the utility of the sessions, half of the participants said that sessions led them to review national guidelines and protocols or make other changes to their health systems. The post-series survey sent following the end of the clinic series showed that at least eight countries subsequently conducted a mini-cPIE after participating in the clinics, and participants from at least nine countries indicated the experience shared by peer countries on the clinic largely benefited their COVID-19 vaccine introduction and deployment. In this article, we highlight the benefits and importance of creating a global experience-sharing forum for countries to connect and share pertinent learnings in real-time during an international public health emergency. Moving forward, it is critical to foster a culture of individual and collective learning within and between countries during public health emergencies, with WHO playing an important convening role.

COVID-19 vaccine hesitancy among adults in India: A primary study based on health behavior theories and 5C psychological antecedents model

Despite the significant success of India's COVID-19 vaccination program, a sizeable proportion of the adult population remains unvaccinated or has received a single dose of the vaccine. Despite the recommendations of the Government of India for the two doses of the COVID-19 vaccine and the precautionary booster dose, many people were still hesitant towards the COVID-19 full vaccination. Hence, this study aimed to identify the primary behavioral and psychological factors contributing to vaccine hesitancy. Cross-sectional data was collected via a multi-stage sampling design by using a scheduled sample survey in the Gorakhpur district of Uttar Pradesh, India, between 15 July 2022 to 30 September 2022. This study has utilized three health behavior models-the Health Belief Model (HBM), the Theory of Planned Behavior (TPB), and the 5C Psychological Antecedents of vaccination, and employed bivariate and multivariable binary logistic regression model to assess the level of vaccine hesitancy and predictive health behavior of the respondents. Results indicate that among the constructs of the HBM and 5C Antecedents models, "perceived benefits", "confidence" and "collective responsibility" showed a lesser likelihood of COVID-19 vaccine hesitancy. However, in the TPB model constructs, a 'negative attitude towards the vaccine' showed a four times higher likelihood of COVID-19 vaccine hesitancy. From the future policy perspective, this study suggested that addressing the issue of 'negative attitudes towards the vaccine' and increasing the trust or confidence for the vaccine through increasing awareness about the benefits of the vaccination in India may reduce vaccine hesitancy.

Understanding Reasons for Vaccination Hesitancy and Implementing Effective Countermeasures: An Online Survey of Individuals Unvaccinated against COVID-19

This online survey of unvaccinated people living in Japan aimed to identify the reasons for declining vaccination and to develop effective countermeasures. We conducted a hierarchical class analysis to classify participants, examine factors influencing their classification, and provide the information they needed about coronavirus disease 2019 (COVID-19) and trusted sources of COVID-19 information for each group. A total of 262 participants were classified into three groups: Group 1 with no specific reason (28 participants, 10.69%); Group 2 with clear concerns about trust in the vaccine (85 participants, 32.44%), and Group 3 with attitudinal barriers, such as distrust of the vaccine and complacency towards COVID-19, and structural barriers, such as vaccination appointments (149 participants, 56.87%). For each group, females tended to be classified in Group 2 more than Group 1 (Odds ratio (OR) [95% confidential intervals (95%CI)] = 1.64 (0.63 to 2.66), p = 0.001) and in Group 3 more than Group 1 (OR [95%CI] = 1.16 (0.19 to 2.12), p = 0.019). The information that the participants wanted to know about COVID-19 was different among each group (Safety: p < 0.001, Efficacy: p < 0.001, Genetic effects: p < 0.001). Those who did not receive the COVID-19 vaccine also had lower influenza vaccination coverage (8.02%). Additionally, 38 participants (14.50%) were subject to social disadvantages because they had not received the COVID-19 vaccine. Countermeasures should be carefully tailored according to the target population, reasons for hesitancy, and specific context. The findings of this study may help develop individualized countermeasures to address vaccine hesitancy.

Temporal changes in factors associated with COVID-19 vaccine hesitancy among Chinese adults: Repeated nationally representative survey

Background

COVID-19 vaccine hesitancy has been cited as one of the main obstacles impacting vaccine coverage. However, factors that affect hesitancy may change over time. Understanding these evolving concerns and adapting strategies accordingly are crucial for effectively addressing vaccine hesitancy effectively and promoting public health. We aimed to explore the temporal changes in factors associated with COVID-19 VH during the COVID-19 pandemic and assess the dynamic evolution of VH.

Methods

In August 2022 and February 2023, repeated online surveys were undertaken to collect information from 5378 adults across four regions of China. Multiple linear regression models assessed the influencing factors of COVID-19 VH. The association between protective motive theory (PMT) (perceived severity, susceptibility, benefits, barriers, and self-efficacy) and VH was evaluated by structural equation modeling (SEM).

Results

Repeated measures showed that 573 (10.7%) and 1598 (29.7%) of the 5378 participants reported COVID-19 VH in the baseline and follow-up surveys, respectively. Educational levels, chronic disease, history of allergy, COVID-19 infection, and trust in medical staff and vaccine developers were positively associated with COVID-19 VH (P＜0.05). The application of SEM revealed that perceived severity, susceptibility, vaccination barriers, and self-efficacy in the PMT directly impacted on VH (P＜0.05). In addition, severity, susceptibility, benefits, and barriers had a significant direct effect on self-efficacy as β = 0.113, β = 0.070, β = 0.722, β = -0.516 respectively with P < 0.001.

Conclusion

The prevalence of COVID-19 VH was relatively low in the baseline survey and much higher in the follow-up survey, with a significant increase in hesitancy rates among mainland Chinese residents. Acknowledging the substantial impact on the shaping of COVID-19 VH, one must consider factors including perceived severity, susceptibility, vaccination barriers, and self-efficacy.

Dynamic predictors of COVID-19 vaccination uptake and their interconnections over two years in Hong Kong

The global rollout of COVID-19 vaccines faces a significant barrier in the form of vaccine hesitancy. This study adopts a dynamic and network perspective to explore the determinants of COVID-19 vaccine uptake in Hong Kong, focusing on multi-level determinants and their interconnections. Following the framework proposed by the Strategic Advisory Group of Experts (SAGE), the study used repeated cross-sectional surveys to map these determinants at multiple levels and investigates their interconnections simultaneously in a sample of 15,179 over two years. The results highlight the dynamic nature of COVID-19 vaccine hesitancy in an evolving pandemic. The findings suggest that vaccine confidence attitudes play crucial roles in vaccination uptake, with their importance shifting over time. The initial emphasis on vaccine safety gradually transitioned to heightened consideration of vaccine effectiveness at a later stage. The study also highlights the impact of chronic condition, age, COVID-19 case numbers, and non-pharmaceutical preventive behaviours on vaccine uptake. Higher educational attainment and being married were associated with primary and booster vaccine uptake and it may be possible to leverage these groups as early innovation adopters. Trust in government acts as a crucial bridging factor linking various variables in the networks with vaccine confidence attitudes, which subsequently closely linked to vaccine uptake. This study provides insights for designing future effective vaccination programmes for changing circumstances.

Vaccination against COVID-19 and socioeconomic inequalities: A cross-sectional study in Ecuador

Background

Equity in vaccination against COVID-19 is a public health concern. The objective of this study was to analyze socioeconomic inequalities related to vaccination for the first and second doses from primary series against COVID-19 in Ecuador.

Methods

Secondary database study in 12,743,507 respondents from 15 years and over. The COVID-19 section of the National Survey of Employment, Unemployment and Underemployment (ENEMDU) was analyzed. Socioeconomic characteristics and vaccination against COVID-19 were associated with the at least one dose and second dose. Poisson regressions for complex samples were obtained.

Results

As of the date of the survey, 87.3% of the sample (95% CI 86.7%-87.8%) had received at least one vaccine against COVID-19. A lower probability of having received at least one vaccine against COVID-19 was found in rural areas (PR 0.82, 95% CI 0.74-0.91), indigenous population (PR 0.43, 95% CI 0.29-0.64), no level of education (PR 0.25, 95% CI 0.14-0.43), and the lowest economic income (PR 0.42, 95% CI 0.35-0.52). A significantly lower probability of vaccination with two or more doses was found in rural vs urban area (PR 0.88, 95% CI 0.80-0.96), women vs men (PR 0.85, 95% CI 0.77-0.91), indigenous population vs white (PR 0.44, 95% CI 0.33-0.59) and individuals in the lowest income quartile vs highest income quartile (PR 0.48, 95% CI 0.42-0.55). Underemployment, population economically inactive (PR 0.77, 95% CI 0.67-0.88 and PR 0.71, 95% CI 0.61-0.83) and individuals with no level of education (PR 0.39, 95% CI 0.27-0.58) also were less likely to complete the primary phase of vaccination compared with individuals in the highest income quartile, employment and postgraduate level of education.

Conclusions

There were socioeconomic inequalities with the primary series of vaccine against COVID-19, with a greater disadvantage for rural residents, women, indigenous populations, lower economic income and lower levels of education.

Discretion in decision to receive COVID-19 vaccines and associated socio-economic inequalities in rates of uptake: a whole-of-population data linkage study from Australia

OBJECTIVE

In Australia, first and second compared to third dose of a COVID-19 vaccine were implemented under different policies and contexts, resulting in greater discretion in decisions to receive a third compared to first and second dose. We quantified socio-economic inequalities in first and third dose to understand how discretion is associated with differences in uptake.

STUDY DESIGN

Whole-of-population cohort study.

METHODS

Linked immunisation, census, death and migration data were used to estimate weekly proportions who received first and third doses of a COVID-19 vaccine until 31 August 2022 for those with low (no formal qualification) compared to high (university degree) education, stratified by 10-year age group (from 30 to 89 years). We estimated relative rates using Cox regression, including adjustment for sociodemographic factors.

RESULTS

Among 13.1 million people in our study population, 94% had received a first and 80% a third dose by 31 August 2022. Rates of uptake of first and third dose were around 50% lower for people with low compared to high education. Gaps were small in absolute terms for first dose, and at the end of the study period ranged from 1 to 11 percentage points across age groups. However, gaps were substantial for third dose, particularly at younger ages where the socio-economic gap was as wide as 32 percentage-points.

CONCLUSION

Education-related inequalities in uptake were larger where discretion in decisions was larger. Policies that limited discretion in decisions to receive vaccines may have contributed to achieving the dual aims of maximising uptake and minimising inequalities.

Pervasive Parental Hesitancy and Resistance towards Measles Rubella Vaccination in Jordan

Measles remains a highly contagious and potentially severe infectious disease, necessitating high vaccine coverage. However, misinformation and measles vaccine hesitancy/resistance have posed significant challenges to achieving this goal. The COVID-19 pandemic further exacerbated these challenges, leading to a measles outbreak in Jordan in 2023. This study aimed to investigate the acceptance of the measles rubella (MR) vaccine among parents in Jordan and to identify its associated determinants. This cross-sectional questionnaire-based study was conducted using a previously Arabic-validated version of the Parental Attitudes towards Childhood Vaccines (PACV) survey instrument. Data collection took place in October 2023, and the final study sample comprised a total of 391 parents, with mothers representing 69.8% of the participants (n = 273). The majority of participating parents expressed either resistance (n = 169, 43.2%) or hesitancy (n = 168, 43.0%) towards MR vaccination, while only 54 participants (13.8%) expressed MR vaccine acceptance. Multivariate analysis revealed that trust in vaccine safety/efficacy, behavior, and having fewer offspring were significantly associated with MR vaccine acceptance. The current study revealed a concerning level of MR vaccine hesitancy/resistance among parents in Jordan, which could signal a public health alarm in the country. Urgent and targeted interventions are strongly recommended to address this issue, including mass campaigns aimed at building trust in the MR vaccine's safety/efficacy. Additionally, there is an urgent need for effective public health initiatives to ensure sufficient measles vaccine coverage to prevent future outbreaks of this serious disease.

Behavioral Changes Associated With COVID-19 Vaccination: Cross-National Online Survey

BACKGROUND

During the initial phases of the vaccination campaign worldwide, nonpharmaceutical interventions (NPIs) remained pivotal in the fight against the COVID-19 pandemic. In this context, it is important to understand how the arrival of vaccines affected the adoption of NPIs. Indeed, some individuals might have seen the start of mass vaccination campaigns as the end of the emergency and, as a result, relaxed their COVID-safe behaviors, facilitating the spread of the virus in a delicate epidemic phase such as the initial rollout.

OBJECTIVE

The aim of this study was to collect information about the possible relaxation of protective behaviors following key events of the vaccination campaign in four countries and to analyze possible associations of these behavioral tendencies with the sociodemographic characteristics of participants.

METHODS

We developed an online survey named "COVID-19 Prevention and Behavior Survey" that was conducted between November 26 and December 22, 2021. Participants were recruited using targeted ads on Facebook in four different countries: Brazil, Italy, South Africa, and the United Kingdom. We measured the onset of relaxation of protective measures in response to key events of the vaccination campaign, namely personal vaccination and vaccination of the most vulnerable population. Through calculation of odds ratios (ORs) and regression analysis, we assessed the strength of association between compliance with NPIs and sociodemographic characteristics of participants.

RESULTS

We received 2263 questionnaires from the four countries. Participants reported the most significant changes in social activities such as going to a restaurant or the cinema and visiting relatives and friends. This is in good agreement with validated psychological models of health-related behavioral change such as the Health Belief Model, according to which activities with higher costs and perceived barriers (eg, social activities) are more prone to early relaxation. Multivariate analysis using a generalized linear model showed that the two main determinants of the drop of social NPIs were (1) having previously tested positive for COVID-19 (after the second vaccine dose: OR 2.46, 95% CI 1.73-3.49) and (2) living with people at risk (after the second vaccine dose: OR 1.57, 95% CI 1.22-2.03).

CONCLUSIONS

This work shows that particular caution has to be taken during vaccination campaigns. Indeed, people might relax their safe behaviors regardless of the dynamics of the epidemic. For this reason, it is crucial to maintain high compliance with NPIs to avoid hindering the beneficial effects of the vaccine.

Healthcare Worker Characteristics Associated with SARS-CoV-2 Vaccine Uptake in Ireland; a Multicentre Cross-Sectional Study

The prevention of SARS-CoV-2 acquisition and transmission among healthcare workers is an ongoing challenge. Vaccination has been introduced to mitigate these risks. Vaccine uptake varies among healthcare workers in the absence of vaccine mandates. We investigated engagement with SARS-CoV-2 vaccination among healthcare workers and identified characteristics associated with lower vaccine uptake. This multi-site cross-sectional study recruited n = 1260 healthcare workers in both clinical and non-clinical roles over a three-month period from November 2022. Participants reported their engagement with the primary SARS-CoV-2 vaccination programme and subsequent booster programmes, as well as providing demographic, occupational and personal medical history information. Multivariable linear regression identified characteristics associated with vaccine uptake. Engagement with vaccination programmes was high, with 88% of participants receiving at least one booster dose after primary vaccination course. Younger age and female sex were associated with reduced vaccine uptake. Healthcare workers in non-clinical roles also had reduced vaccine uptake. These findings should inform vaccination strategies across healthcare settings and target populations with reduced vaccine uptake directly, in particular young, female, and non-clinical healthcare workers, both for SARS-CoV-2 and other healthcare-associated vaccine-preventable infections.

Measuring income-associated inequalities in COVID-19 vaccination on a global scale: a modeling study

Inequalities in the accessibility and utilization of quality, safe, and effective coronavirus disease 2019 (COVID-19) vaccines across and within countries limited their value in protecting health during the COVID-19 pandemic. We quantified cross-country, income-associated inequality in COVID-19 vaccination using statistical models based on the data for 79 countries through December 2021. We found notable inequality in vaccinations per capita. At least 11.9% of doses administered in high-income countries could be redistributed to low-income countries to substantially reduce income-associated inequality in vaccinations. The results of this modeling study indicate that reliance on multiple doses of vaccine to attain optimal protection from COVID-19 is a significant contributor to inequality in vaccinations per capita. Dose-sharing mechanisms should account for and include efforts to optimize the capabilities of health systems to deliver vaccines.

The Role of Hyperarousal and Aberrant Salience in the Acceptance of Anti-COVID-19 Vaccination

Background and Objectives: This present study was aimed at exploring hyperarousal and aberrant salience in a sample of the Italian general population to understand their possible role in the acceptance of anti-COVID-19 vaccination. Materials and Methods: Sociodemographic data questions, the "Acceptance of Vaccination" measure, the Hyperarousal Scale (H-Scale), and the Aberrant Salience Inventory (ASI) were sent as an unpaid online survey to the general population (age range 18-80 years) within the Italian territory. Results: The enrolled subjects were divided into two subgroups: "Pro-vax" (n = 806; 87.4%) and "No-vax" (n = 116; 12.6%). Statistical analysis showed significant differences between groups in the "Education Level" (p = 0.001) category, higher in the "Pro-vax" group, and in the ASI "Senses Sharpening" (p = 0.007), "Heightened Emotionality" (p = 0.008), and "Heightened Cognition" (p = 0.002) subscales with the "Total Score" (p = 0.015), all higher in "No-vax" subjects. Furthermore, a linear regression model evidenced that only "Education Level" (β = 0.143; p < 0.0001) and "Senses Sharpening" (β = -0.150; p = 0.006) were, respectively, direct and inverse predictors of "Acceptance of Vaccination". Conclusions: Our results show that several subthreshold conditions, such as somatosensory amplification, anxiety traits, and panic experiences, should be taken into account by authoritative sources involved in health education, communication, and policy to alleviate public concerns about vaccine safety, for the present and also future pandemics, and to provide more inclusive, informed, and accurate public health preventive and treatment programs.

The evolution of COVID-19 vaccine hesitancy in Sub-Saharan Africa: evidence from panel survey data

BACKGROUND

COVID-19 vaccination efforts are lagging in Sub-Saharan Africa, as just over 20 percent of the population has been fully vaccinated. COVID-19 vaccine hesitancy is considered important as a prerequisite for widespread vaccine take-up. Here, we study the dynamics of vaccine acceptance, its correlates, and reasons for hesitancy over time, drawing on two years of panel survey data.

METHODS

In this observational study, we use multiple rounds of data from national High Frequency Phone Surveys (HFPS) in five countries in East and West Africa (Burkina Faso, Ethiopia, Malawi, Nigeria, and Uganda), covering a period between 2020 and 2022. The surveys are cross-country comparable and draw their samples from nationally representative sampling frames. Based on this data source, the study presents population-weighted means and performs multivariate regression analysis.

RESULTS

COVID-19 vaccine acceptance was high throughout the study period (68% to 98%). However, acceptance levels were lower in 2022 than in 2020 in three countries (Burkina Faso, Malawi, Nigeria), and higher in one country (Uganda). Moreover, individuals are observed to change their stated vaccine attitudes between survey rounds, to a limited extent in some countries (Ethiopia) and more frequently in others (Burkina Faso, Malawi, Nigeria, Uganda). Vaccine hesitancy is higher in richer households, and those residing in urban areas; among women and those better educated. Hesitancy is lower in larger households and among heads of the household. The main reasons for hesitancy are concerns about side effects of the vaccine, its safety and efficacy, as well as assessments of COVID-19 risk, though these reasons fluctuate over time.

CONCLUSIONS

Reported COVID-19 vaccine acceptance levels remain far above vaccination rates in the study countries, suggesting that vaccine hesitancy is not the primary obstacle to reaching greater vaccine coverage, which may instead be related to access and delivery barriers as well as supply shortages. Nevertheless, vaccine attitudes appear malleable so that continued efforts are needed to retain high levels of vaccine acceptance.

Investigating the Marginal and Herd Effects of COVID-19 Vaccination for Reducing Case Fatality Rate: Evidence from the United States between March 2021 to January 2022

Vaccination campaigns have been rolled out in most countries to increase vaccination coverage and protect against case mortality during the ongoing pandemic. To evaluate the effectiveness of COVID-19 vaccination, it is vital to disentangle the herd effect from the marginal effect and parameterize them separately in a model. To demonstrate this, we study the relationship between the COVID-19 vaccination coverage and case fatality rate (CFR) based on U.S. vaccination coverage at county level, with daily records from 11 March 2021 to 26 January 2022 for 3109 U.S. counties. Using segmented regression, we discovered three breakpoints of the vaccination coverage, at which herd effects could potentially exist. Controlling for county heterogeneity, we found the size of the marginal effect was not constant but actually increased as the vaccination coverage increased, and only the herd effect at the first breakpoint to be statistically significant, which implied an indirect benefit of vaccination may exist at the early stage of a vaccination campaign. Our results demonstrated that public-health researchers should carefully differentiate and quantify the herd and marginal effects when analyzing vaccination data, to better inform vaccination-campaign strategies as well as evaluate vaccination effectiveness.

COVID-19 vaccine acceptance and related behavioral and psychological characteristics in individuals with mental disorders in Korea

Objective

This study aimed to investigate COVID-19 vaccine acceptance and related factors in individuals with mental disorders in Korea.

Methods

We surveyed 572 individuals with mental disorders about their attitudes toward COVID-19 vaccination using a 7-item self-rating questionnaire on vaccine acceptance and hesitancy. We categorized the respondents into groups based on their level of vaccine acceptance using hierarchical clustering. In addition, we evaluated the respondents' vaccination status and trust in sources of information regarding COVID-19 vaccines, and assessed their psychological characteristics using the Patient Health Questionnaire-9, Gratitude Questionnaire-6, and Big Five Inventory-10.

Results

Clustering revealed three groups according to vaccine acceptance: 'totally accepting' (n= 246, 43.0%), 'somewhat accepting' (n= 184, 32.2%), and 'hesitant' (n= 142, 24.8%) groups. Three quarters of all participants, who belonged to the 'totally accepting' or 'somewhat accepting' groups, were willing to receive a COVID-19 vaccine despite concerns about its side effects. Individuals in the high vaccine acceptance group were older (F= 12.52, p< 0.001), more likely to receive the influenza vaccine regularly, and more likely to trust formal information sources. Additionally, they had higher levels of gratitude (F= 21.00, p< 0.001) and agreeableness (F= 4.50, p= 0.011), and lower levels of depression (χ²= 11.81, p= 0.003) and neuroticism (F= 3.71, p= 0.025).

Conclusion

The present study demonstrated that individuals with mental disorders were generally willing to receive COVID-19 vaccination. However, they weighed its need and effectiveness against potential side effects before coming to a decision. It is important to understand the behavioral and psychological characteristics associated with vaccine acceptance, to effectively communicate its importance to individuals with mental disorders.

Factors Influencing the Intention and Uptake of COVID-19 Vaccines on the African Continent: A Scoping Review

The COVID-19 pandemic is a severe concern worldwide, particularly in Africa. Vaccines are crucial in the fight against the COVID-19 pandemic. This scoping review examined existing literature from 2020 to 2022 on individual, interpersonal, and structural barriers and facilitators to COVID-19 vaccination within Africa to facilitate more informed health promotion interventions to improve vaccine uptake. This review was conducted using Arksey and O'Malley's five-stage methodological framework. A comprehensive search was undertaken from 2021 to 2022 using six electronic databases: EBSCOhost, PubMed, Web of Science, ProQuest, WorldCat Discovery, and Google Scholar. Data was collected, charted into themes, and summarized using a standard data extraction sheet in Microsoft Excel. A total of forty (n = 40) published academic articles were reviewed, with many conducted in Nigeria (n = 10), followed by Ethiopia (n = 5) and Ghana (n = 4) and the rest elsewhere in Africa. Thematic narratives were used to report data into six themes: attitudes and perceptions about COVID-19 vaccines, intention to uptake COVID-19 vaccines; factors and barriers associated with COVID-19 vaccine uptake; socio-demographic determinants affecting the intention and uptake; and information sources for COVID-19 vaccines. The intention for uptake ranged from 25% to 80.9%, resulting in a suboptimal uptake intention rate (54.2%) on the African continent. Factors that promoted vaccine acceptance included confidence in the COVID-19 vaccines and the desire to protect people. Age, education, and gender were the most common factors significantly associated with vaccine acceptance. Most studies revealed that considerable barriers to vaccine uptake exist in Africa. Concerns about potential side effects, vaccine ineffectiveness, a perceived lack of information, and inaccessibility were among the individual, interpersonal, and structural barriers to COVID-19 vaccine uptake. The unwillingness to receive the COVID-19 vaccine was strongly correlated with being female. Mass and social media were the main sources of information regarding COVID-19 vaccines. To encourage vaccine uptake, governments should pay attention to refuting misinformation through integrated community-based approaches, such as creating messages that convey more than just information.

Within-Country Inequality in COVID-19 Vaccination Coverage: A Scoping Review of Academic Literature

Since December 2020, COVID-19 vaccines have become increasingly available to populations around the globe. A growing body of research has characterised inequalities in COVID-19 vaccination coverage. This scoping review aims to locate, select and assess research articles that report on within-country inequalities in COVID-19 vaccination coverage, and to provide a preliminary overview of inequality trends for selected dimensions of inequality. We applied a systematic search strategy across electronic databases with no language or date restrictions. Our inclusion criteria specified research articles or reports that analysed inequality in COVID-19 vaccination coverage according to one or more socioeconomic, demographic or geographic dimension of inequality. We developed a data extraction template to compile findings. The scoping review was carried out using the PRISMA-ScR checklist. A total of 167 articles met our inclusion criteria, of which half (n = 83) were conducted in the United States. Articles focused on vaccine initiation, full vaccination and/or receipt of booster. Diverse dimensions of inequality were explored, most frequently relating to age (n = 127 articles), race/ethnicity (n = 117 articles) and sex/gender (n = 103 articles). Preliminary assessments of inequality trends showed higher coverage among older population groups, with mixed findings for sex/gender. Global research efforts should be expanded across settings to understand patterns of inequality and strengthen equity in vaccine policies, planning and implementation.