Factors Affecting Hesitancy to mRNA and Viral Vector COVID-19 Vaccines among College Students in Italy

Are psychological attitudes towards vaccination an expression of personality? A cross-sectional study on COVID-19 vaccination in France

BACKGROUND

The capacity of the 7C model's psychological antecedents, which include confidence in vaccines, complacency, convenience, calculation, collective responsibility, confidence in the wider system, and social conformism, to explain variance in COVID-19 vaccine intentions and behaviours has been documented. However, it remains unclear whether the attitudes represented by the 7C psychological antecedents are specific to vaccination or if they are, in fact, an expression of underlying personality traits.

METHODS

From February to June 2022, French adults completed self-administered questionnaires assessing COVID-19 vaccination history, the 7C antecedents, and personality traits ("ComCor" and "Cognitiv" studies). Vaccination behaviours were studied through three outcomes: at-least-one-dose vaccination status by 2022 (N = 49,019), up-to-date vaccination status (N = 46,566), and uptake speed of first dose (N = 25,998). Personality traits were evaluated using the French version of the Big Five Inventory (BFI-Fr). Multivariable logistic regressions and Cox models predicting vaccine behaviours were run with the 7C antecedents, both with and without personality traits.

RESULTS

Among the 49,019 participants, 95.0% reported receipt of at least one dose and 89.8% were up to date with recommendations. All 7C antecedents were significantly associated with the outcomes. The inclusion of personality traits did not substantially alter the effect estimates of the association between the 7C antecedents and vaccination behaviours, with differences between effect sizes of models with and without personality traits being < 5%.

CONCLUSIONS

Our results suggest that the 7C psychological antecedents of vaccination are not the mere expression of personality and that their impact on vaccine behaviours is independent of personality traits. As such, the 7C antecedents may be modifiable by appropriate information and vaccine promotion.

TRIAL REGISTRATION

The "ComCor" study received ethical approval by the Comité de Protection des Personnes Sud Ouest et Outre Mer 1 on 21/09/2020. The addition of the "Cognitiv" questionnaire received ethical approval by the Comité de Protection des Personnes Sud Ouest et Outre Mer 1 on 01/02/2022. The data protection authority Commission Nationale de l'Informatique et des Libertés (CNIL) authorised the processing of data on 21/10/2020. The study is registered with ClinicalTrials.gov under the identifier NCT04607941.

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

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

Recent advances in nanogels for drug delivery and biomedical applications

Nanotechnology has shown great promise for researchers to develop efficient nanocarriers for better therapy, imaging, and sustained release of drugs. The existing treatments are accompanied by serious toxicity limitations, leading to severe side effects, multiple drug resistance, and off-target activity. In this regard, nanogels have garnered significant attention for their multi-functional role combining advanced therapeutics with imaging in a single platform. Nanogels can be functionalized to target specific tissues which can improve the efficiency of drug delivery and other challenges associated with the existing nanocarriers. Translation of nanogel technology requires more exploration towards stability and enhanced efficiency. In this review, we present the advances and challenges related to nanogels for cancer therapy, ophthalmology, neurological disorders, tuberculosis, wound healing, and anti-viral applications. A perspective on recent research trends of nanogels for translation to clinics is also discussed.

Factors Influencing COVID-19 Vaccine Hesitancy in Pregnant and Breastfeeding/Puerperium Women: A Cross-Sectional Study

Vaccination among pregnant and breastfeeding women is critical for protecting this vulnerable population and their children. COVID-19 vaccination is recommended both during pregnancy and breastfeeding; however, we still do not fully understand the determinants that influence hesitancy towards COVID-19 vaccination. This study aimed to identify the determinants of vaccine hesitancy in pregnant and breastfeeding, puerperium women. A multicenter, cross-sectional study, involving 435 pregnant and breastfeeding women, was conducted. Vaccination hesitancy was evaluated by administering the Vaccination Attitudes (VAX) Scale and the Zung Anxiety Self-Assessment Scale (SAS) was adopted to measure anxiety levels. Overall, 14% of the participants reported that they did not receive the COVID-19 vaccine, and 78.3% received their first dose during pregnancy or while breastfeeding. The descriptive statistics for the VAX scale showed a total mean score of 3.35 (±1.6), and 75% of participants reported an anxiety index equal to or lower than the threshold. Vaccine hesitancy increased as "adverse events after vaccination" increased (p < 0.01), while SAS levels positively correlated with the participants' mean age (p < 0.05). Investigating the factors influencing vaccine hesitancy enables the development of targeted health policies and SARS-CoV-2 vaccination programs.

Are the 7C psychological antecedents associated with COVID-19 vaccine behaviours beyond intentions? A cross-sectional study on at-least-one-dose and up-to-date vaccination status, and uptake speed among adults in France

BACKGROUND

Widely documented psychological antecedents of vaccination are confidence in vaccines, complacency, convenience, calculation, collective responsibility (5C model) with the recent addition of confidence in the wider system and social conformism. While the capacity of these seven antecedents (7C) to explain variance in COVID-19 vaccine intentions has been previously documented, we study whether these factors also are associated with vaccine behaviours, beyond intentions.

METHODS

From February to June 2022, we recruited a sample of adults in France, including persons with notified recent SARS-CoV-2 infection, along with relatives and randomly selected non-infected persons. Participants completed self-administered questionnaires assessing COVID-19 vaccination history and the 7C antecedents. We defined vaccination behaviours as three outcomes: at-least-one-dose vaccine status by 2022 (N = 49,019), up-to-date vaccination status (N = 46,566), and uptake speed of first dose (N = 25,998). We conducted multivariable logistic regressions and Cox models.

RESULTS

Among the 49,019 participants, 95.0% reported receipt of at least one dose and 89.8% were up to date with recommendations. All 7C antecedents were significantly associated with the outcomes, although effects were weaker for up-to-date vaccination status and uptake speed. The strongest effects (most vs. least vaccine-favourable attitude level, at-least-one-dose vaccination status) were observed for collective responsibility (OR: 14.44; 95%CI: 10.72-19.45), calculation (OR: 10.29; 95%CI: 7.53-14.05), and confidence in the wider system (OR: 8.94; 95%CI: 6.51-12.27).

CONCLUSION

This study demonstrates that the 7C not only explain vaccine intention, but also vaccine behaviours, and underpins the importance of developing vaccine promotion strategies considering the 7C antecedents.

Anxiety and fear of COVID-19 as potential mechanisms to explain vaccine hesitancy among adults

Background

Vaccine hesitancy is a significant global problem resulting from the interaction of multiple factors, including mental health factors. However, the association of COVID-19 vaccine hesitancy with mental health has not been well-examined, especially in Arab culture. This study aims to identify the correlation between anxiety/fear of COVID-19 and vaccine hesitancy among Saudi adults.

Methods

An online-based survey was administered to 558 participants from all regions of Saudi Arabia using the snowball technique. However, this sample may not be representative of the Saudi adult population. Participants responded to the Questionnaire of Vaccine Hesitancy, the COVID-19-Anxiety Questionnaire (C-19-A), and the Fear of COVID-19 Scale (FCV-19S). Data were analyzed on vaccine uptake, vaccine hesitancy, coronavirus infection, and demographic variables. The predictive factors of vaccine hesitancy were examined in one model using multiple regression analysis by the Enter method (P= 0.05).

Results

COVID-19 anxiety and fear have significant correlations with vaccine hesitancy (Phi=0.33, P=0.017; Phi=0.29, P=0.013, respectively). Anxiety and fear were higher among unhesitating participants (t =2.469, P=0.014; t=2.025, P=0.043, respectively). Participants who had previously been infected with coronavirus were more likely to be hesitant (X2 = 23.126, P=0.000). Participants who scored high in anxiety were more likely to be vaccinated (F=3.979, P=0.019) and have a secondary school or college education (F=4.903 P=0.002). COVID-19 anxiety, gender, and coronavirus infection significantly predicted vaccine hesitancy.

Conclusion

Anxiety and fear of COVID-19 are among the most important factors correlated with vaccine hesitancy; unhesitant people are more likely to have anxiety and fear. COVID-19 anxiety significantly predicted vaccine hesitancy. We recommend integrating psychological care into vaccination plans to help increase the uptake rate during potential subsequent pandemics. Relevant intervention programs can be designed to help increase vaccine acceptance, deal with vaccine hesitancy, and relieve psychological symptoms during major pandemics. Psychologists can provide awareness messages, counselling seminars, online mentoring, or telemental health outreach.

Psychological and Social Aspects of Vaccination Hesitancy-Implications for Travel Medicine in the Aftermath of the COVID-19 Crisis: A Narrative Review

Vaccines are an important tool of preventive medicine. Although organized vaccination programs have saved large populations from serious infectious diseases, there is a considerable part of the population who oppose vaccinations. In particular, anti-vaccination perceptions, among travelers to countries with endemic diseases, are a major public health concern. Although hesitancy towards vaccinations is not a novel phenomenon, it came back to the forefront during the fight against the COVID-19 pandemic. This review explores the etiology of anti-vaccination beliefs among travelers and draws conclusions about their impact on public health and society in general. For this purpose, a purposeful search for data on the causative factors of vaccine hesitancy and their impact on people's health was conducted. A descriptive analysis of the findings and conclusions regarding possible implications in health policy and clinical practice are presented. A fear of side effects, lack of credence in the necessity of vaccines, and mistrust of medical authorities are important causative factors. Their interplay shapes hesitancy towards vaccines. However, anti-vaccination beliefs can also be an aspect of a more general unconventional stance of life. Health care professionals and organizations must be ready to tackle vaccine hesitancy by making the necessary interventions. Correcting misconceptions about vaccinations is a prerequisite for ensuring personal and public health, especially in the context of a pandemic or epidemic. Moreover, ensuring the efficacy and safety of vaccines, especially in cases of modern technology applications, is a fundamental factor in addressing people's concerns about vaccines. For this purpose, medical authorities and organizations must provide accurate and clear information on vaccines so as to eliminate misinformation. Furthermore, clinicians should cultivate their communication skills in order to convey the appropriate messages to prospective recipients of vaccinations.

Between nudges and mandates: The drivers of COVID-19 vaccination intentions and subsequent uptake in Russia

Despite high levels of morbidity and mortality, as well as the widespread availability of domestic vaccines, Russia demonstrated significantly low rates of vaccination throughout the COVID-19 pandemic. This research explores vaccination intentions before the start of the immunisation campaign and the consequent uptake in Russia after the introduction of mandatory vaccination policy in certain industries and proof-of-immunisation for social activities. Using a nationally representative panel dataset, we analyse factors behind individual vaccination decisions using binary and multinomial logistic regressions. Special attention is given to the effect of employment in industries with vaccine mandates and personal factors which determine individual "nudgeability" to vaccination (e.g., personality traits, beliefs, vaccine alertness, self-perceived vaccine availability etc.). Our results show that 49 per cent of the population received at least one shot of COVID-19 vaccine by autumn 2021 after the introduction of mandatory vaccination. Vaccination intentions before the rollout of the nationwide immunisation campaign are correlated with the consequent attitudes and uptake, although the prediction is not perfect. 40 percent of vaccine refusers eventually got vaccinated, while 16 percent of vaccine supporters turned into refusers, revealing the lack of promotion of vaccine safety and effectiveness. To a large extent, vaccination refusal and hesitance are explained by vaccine alertness. Vaccine mandates significantly increased the uptake in several affected industries, especially education. These results offer important insights for designing information policy, relevant for future vaccination campaigns.

Scale Development for COVID-19 Vaccine Hesitancy by Integration of Socio-Demographic and Psychological Factors

Vaccination is the most cost-effective way to maintain population health. However, it can only be effective if widespread acceptance is held. The efficacy of COVID-19 vaccines depends on their favor. When countries start to vaccinate their citizens, there is a certain level of skepticism about the effectiveness of the vaccines. The hesitancy study on vaccines has gained momentum following the pandemic. However, few studies have examined the link between the psychological and sociodemographic factors influencing the fit. This paper proposes integrating the concepts of the information systems success and stimulus-organism-response into a cognitive fit theory framework to explore the integration of psychological and sociodemographic factors in the receivers' reactions (n = 1510). This study analyses the factors that influence the hesitancy of vaccines and the public's refusal in Asia and Europe. Receivers' reactions were assessed to various stimuli and we explored the link between psychological and sociodemographic elements and the concept of fit. Two surveys were conducted following the scale development of Mackenzie. The first was to develop the fit scale, while the second was to validate the fit scale. The results of the second survey were analyzed using structural equation modelling. The results indicate that the scale's fit development is valid and reliable. The quality of the vaccine information, the psychological characteristics of the vaccine system, and vaccine receivers' satisfaction are also beneficial factors for emotional and cognitive fit. Maintaining the vaccines' quality and efficiency can help improve the fit between sociodemographic and psychological characteristics. It can also enhance receivers' satisfaction and encourage continued vaccine administration. This study is regarded as one of the first to examine and develop an emotional and cognitive fit scale for practitioners and researchers.

The Psychology of COVID-19 Booster Hesitancy, Acceptance and Resistance in Australia

COVID-19 booster vaccinations have been recommended as a primary line of defence against serious illness and hospitalisation. This study identifies and characterises distinct profiles of attitudes towards vaccination, particularly the willingness to get a booster dose. A sample of 582 adults from Australia completed an online survey capturing COVID-related behaviours, beliefs and attitudes and a range of sociodemographic, psychological, political, social and cultural variables. Latent Profile Analysis (LPA) identified three subgroups: Acceptant (61%), Hesitant (30%) and Resistant (9%). Compared to the Acceptant group, the Hesitant and Resistant groups were less worried about catching COVID-19, used fewer official COVID-19 information sources, checked the news less, were lower on the agreeableness personality dimension and reported more conservatism, persecutory thinking, amoral attitudes and need for chaos. The Hesitant group also reported checking the legitimacy of information sources less, scored lower on the openness to new experiences personality dimension and were more likely than the Resistant and Acceptant groups to report regaining freedoms (e.g., travel) and work requirements or external pressures as reasons to get a booster. The Resistant group were higher on reactance, held more conspiratorial beliefs and rated their culture as being less tolerant of deviance than the Hesitant and Acceptant groups. This research can inform tailored approaches to increasing booster uptake and optimal strategies for public health messaging.

COVID-19 Vaccine Refusal and Delay among Adults in Italy: Evidence from the OBVIOUS Project, a National Survey in Italy

BACKGROUND

Vaccine hesitancy was defined by the World Health Organization (WHO) in 2019 as a major threat to global health. In Italy, reluctance to receive vaccines is a widespread phenomenon that was amplified during the COVID-19 pandemic by fear and mistrust in government. This study aims to depict different profiles and characteristics of people reluctant to vaccinate, focusing on the drivers of those who are in favor of and those who are opposed to receiving the COVID-19 vaccine.

METHODS

A sample of 10,000 Italian residents was collected. A survey on COVID-19 vaccination behavior and possible determinants of vaccine uptake, delay, and refusal was administered to participants through a computer-assisted web interviewing method.

RESULTS

In our sample, 83.2% stated that they were vaccinated as soon as possible ("vaccinators"), 8.0% delayed vaccination ("delayers"), and 6.7% refused to be vaccinated ("no-vaccinators"). In general, the results show that being female, aged between 25 and 64, with an education level less than a high school diploma or above a master's degree, and coming from a rural area were characteristics significantly associated with delaying or refusing COVID-19 vaccination. In addition, it was found that having minimal trust in science and/or government (i.e., 1 or 2 points on a scale from 1 to 10), using alternative medicine as the main source of treatment, and intention to vote for certain parties were characteristics associated with profiles of "delayers" or "no-vaccinators". Finally, the main reported motivation for delaying or not accepting vaccination was fear of vaccine side effects (55.0% among delayers, 55.6% among no-vaccinators).

CONCLUSION

In this study, three main profiles of those who chose to be vaccinated are described. Since those who are in favor of vaccines and those who are not usually cluster in similar sociodemographic categories, we argue that findings from this study might be useful to policy makers when shaping vaccine strategies and choosing policy instruments.

Learning from the Past to Improve the Future—Vaccine Hesitancy Determinants in the Italian Population: A Systematic Review

WHO identifies vaccine hesitancy (VH) as one of the ten threats to global health. The authors bring to the international scientific community an Italian episode that offers the opportunity to renew the discussion on the extent of the VH matter. The purpose of this systematic review is to analyze the factors determining vaccine hesitancy in the Italian population, to understand its roots, and suggest potential strategies to mitigate it. A systematic review of the literature according to the PRISMA guidelines was carried out using the SCOPUS and Medline (via PubMed) databases, using the following strategy: (COVID-19 vaccines) AND (vaccination hesitancy) AND (Italy). After the selection process, 36 articles were included in this systematic review. The most frequently detected factors associated with VH in the Italian population can be grouped as vaccine-related factors, socio-cultural factors, and demographic factors. Currently, we are facing a gap between the population and science, governments, and institutions. To heal this breach, it is necessary to strengthen the trust of the population through the implementation of health communication and public education strategies, while scientific literacy must continue to support families and individuals in discerning evidence from opinions to recognize the real risks and balance them with the benefits.

COVID-19 Vaccine Hesitancy and Personality Traits; Results from a Large National Cross-Sectional Survey in Qatar

Attitudes to vaccination arise from a complex interplay of personal and environmental factors. This has been true for the COVID-19 vaccination attitudes too and understanding personal factors would help design immunisation strategies that help in infectious disease control. The five-factor model of personality has been established as a valid construct in exploring individual attitudes and traits. This institutional review board approved study explores the relationship between these five domains of personality and attitudes to COVID-19 vaccination in Qatar which has a migrant majority population. A cross-sectional survey was conducted in Qatar using an online survey link containing validated tools to measure vaccine hesitancy and personality traits. People from diverse ethnic and sociodemographic backgrounds, amounting to 5340 individuals, completed the self-report survey. After controlling for social and demographic variables, individuals scoring significantly higher on Conscientiousness were more likely to refuse the COVID-19 vaccination, while those scoring significantly lower on Openness to experience and Neuroticism were also more likely to refuse COVID-19 vaccination. Both groups of individuals scoring significantly higher and lower on Conscientiousness and Neuroticism, respectively, were more likely to trust their own research than trust endorsement of the COVID-19 vaccine from their doctor or healthcare organisation. The study highlights the highly complex and sometimes contradictory relationship between vaccine hesitancy and personality traits and makes a case for understanding this relationship better in order to inform successful immunisation strategies.

Concerns about and stimuli of COVID-19 vaccination hesitancy among diverse occupational groups in metropolitan areas of China: a cross-sectional study

OBJECTIVES

In this study, we aimed to identify concerns and stimuli regarding COVID-19 vaccination acceptance and to compare the findings by occupation.

METHODS

We conducted a cross-sectional study of individuals vaccinated against COVID-19 between 1 April and 30 June 2021 in four metropolitan areas of China. A total of 20 863 participants completed questionnaires, 20 767 of which were eligible for analysis. We used ordered logistic regression to assess the association of vaccination concerns and stimuli with vaccination hesitancy according to occupation.

RESULTS

Farmers were mainly concerned about the quality of vaccines (adjusted OR (aOR): 3.18, 95% CI (CI): 1.83 to 5.54). Among civil servants, media publicity reduced hesitancy (aOR: 0.44, 95% CI: 0.21 to 0.92). Among medical staff, concerns about a short duration of protective effects increased hesitancy (aOR: 8.31, 95% CI: 2.03 to 33.99). For most occupations, concerns about side effects, poor protective effects and health status increased hesitancy. In contrast, protecting oneself and protecting others acted as a stimulus to decrease hesitancy. Interestingly, 'people around me have been vaccinated' was associated with higher vaccination hesitancy among farmers (aOR: 2.19, 95% CI: 1.20 to 4.00).

CONCLUSION

The association of vaccination concerns and stimuli with vaccination hesitancy varied by occupation. The characteristics and concerns of specific target audiences should be considered when designing informational campaigns to promote vaccination against COVID-19.

A systematic literature review to clarify the concept of vaccine hesitancy

Vaccine hesitancy (VH) is considered a top-10 global health threat. The concept of VH has been described and applied inconsistently. This systematic review aims to clarify VH by analysing how it is operationalized. We searched PubMed, Embase and PsycINFO databases on 14 January 2022. We selected 422 studies containing operationalizations of VH for inclusion. One limitation is that studies of lower quality were not excluded. Our qualitative analysis reveals that VH is conceptualized as involving (1) cognitions or affect, (2) behaviour and (3) decision making. A wide variety of methods have been used to measure VH. Our findings indicate the varied and confusing use of the term VH, leading to an impracticable concept. We propose that VH should be defined as a state of indecisiveness regarding a vaccination decision.

Reasons underlying the intention to vaccinate children aged 5-11 against COVID-19: A cross-sectional study of parents in Israel, November 2021

Vaccination is a key tool to mitigate impacts of the COVID-19 pandemic. In Israel, COVID-19 vaccines became available to adults in December 2020 and to 5-11-year-old children in November 2021. Ahead of the vaccine roll-out in children, we aimed to determine whether surveyed parents intended to vaccinate their children and describe reasons for their intentions. We collected information on parental socio-demographic characteristics, COVID-19 vaccine history, intention to vaccinate their children against COVID-19, and reasons for parental decisions using an anonymous online survey. We identified associations between parental characteristics and plans to vaccinate children using a logistic regression model and described reasons for intentions to vaccinate or not. Parental non-vaccination and having experienced major vaccination side effects were strongly associated with non-intention to vaccinate their children (OR 0.09 and 0.18 respectively, p < .001). Parents who were younger, lived in the socio-economically deprived periphery, and belonged to the Arab population had lower intentions to vaccinate their children. Reasons for non-intention to vaccinate included concerns about vaccine safety and efficacy (53%, 95%CI 50-56) and the belief that COVID-19 is a mild disease (73%, 95%CI 73-79), while a frequent motive for vaccination was the return to normal social and educational life (89%, 95%CI 87-91). Understanding rationales for COVID-19 vaccine rejection or acceptance, as well as parental demographic data, can pave the way for intentional educational campaigns to encourage not only vaccination against COVID-19, but also regular childhood vaccine programming.

The relationship between fear of COVID-19 infection, fear of COVID-19 vaccination and Big Five personality traits: a mediation model

BACKGROUND

The primary objective of our correlational, cross-sectional study was to determine the relationship between fear of COVID-19 infection and fear of COVID-19 vaccination and the role of the Big Five personality traits in this relationship.

PARTICIPANTS AND PROCEDURE

The study sample consisted of 462 participants, including 286 women and 176 men, aged 18 to 75, recruited from the general population. The Big Five personality traits were diagnosed using the Polish version of the Ten-Item Personality Inventory. We used an 11-point numerical rating scale to measure the intensity of fear of COVID-19 infection as well as fear of COVID-19 vaccination.

RESULTS

The results indicate that fear of infection has a weak positive correlation with fear of vaccination. Both types of fear have a weak negative correlation with emotional stability and openness to experience. People diagnosed with COVID-19 have significantly higher levels of fear of vaccination and lower levels of emotional stability compared to those without a COVID-19 diagnosis. Fear of infection proves a good predictor of fear of vaccination and a likely mediator between emotional stability and fear of vaccination against COVID-19.

CONCLUSIONS

The results may increase our understanding of the role of personality traits, such as emotional stability, in the fear of infection and COVID-19 vaccination hesitancy.

Immunogenicity, effectiveness, safety and psychological impact of COVID-19 mRNA vaccines

In December 2019, a new single-stranded RNA coronavirus, SARS-CoV-2, appeared in China and quickly spread around the world leading to a pandemic. Infection with SARS-CoV-2 generates symptoms ranging from asymptomatic to severe, occasionally requiring hospitalization in intensive care units, and, in more severe cases, leading to death. Scientists and researchers around the world have made a real race against time to develop various vaccines to slow down and stop the spread of the virus. In addition to conventional viral vector vaccines, new generation mRNA vaccines, BNT152b2 (Comirnaty) and mRNA-1273 (Spikevax), have been developed respectively by Pfizer/BioNTech and Moderna. These vaccines act on immune cells to induce an immune response with the production of specific antibodies against Spike protein of SARS-CoV-2, and to stimulate the differentiation of T and B memory cells. The objective of this review is to provide a detailed picture of the validity of these new vaccines and the safety of vaccination. Not only was the immunogenic effect of mRNA vaccines evaluated, but also the psychosocial impact they had on the population. The data collected show that this type of vaccine can also be an excellent candidate for future treatment and eradication of possible new pathologies with viral and non-viral etiology.

Determinants of COVID-19 vaccine hesitancy and resistance in Russia

Vaccination is the main tool available to handle the COVID-19 pandemic globally. Though no vaccine is proven to be 100% effective, vaccination secures against getting seriously ill and dying from the disease. Russia announced the development of its first domestic vaccine back in August 2020 and launched the nationwide immunization campaign at the beginning of 2021. Despite these achievements, as of mid-October 2021, only 36% of the population got at least one shot of the vaccine. Massive vaccination hesitancy and refusal pose a great threat to public health and postpone social and economic recovery. Using nationally representative data from the general adult population of Russia, this study explores the scope of vaccination hesitancy and refusal as well as the determinants of vaccination attitudes. The results suggest that only 45% of the Russian population demonstrated positive attitudes towards the COVID-19 vaccination prior to the launch of a nationwide vaccination program. We analyze a wide array of demographic, socio-economic, and health-related factors in relation to vaccination intentions and explore the deep-rooted causes of vaccination reluctance by looking at personality traits, religiosity, and trust. The obtained results are vital for designing policy measures to promote vaccination.

A large cross-sectional survey of COVID-19 vaccination willingness amongst healthcare students and professionals: Reveals generational patterns

AIMS

To determine coronavirus disease 2019 (COVID-19) vaccination hesitancy in healthcare professionals and healthcare students in Italy across four generations (baby boomers, generations X, Y and Z).

DESIGN

A cross-sectional descriptive study was performed through an online survey conducted from May to June 2021. The STROBE guidelines were adopted for reporting.

METHODS

Data were collected by initially sending a survey link to a convenience sample of healthcare professionals and students, which was followed by snowball sampling. The VAX scale was validated and adopted. An ANOVA was performed to detect differences in vaccine-hesitancy beliefs between the four generational groups.

RESULTS

The survey was completed by 1226 healthcare professionals and students. Worries about unforeseen future effects accounted for the higher vaccination hesitancy factor across generations. More positive attitudes towards COVID-19 vaccination were expressed by members of generation Z than by members of generation Y and baby boomers. Members of generation X had the highest vaccination hesitancy scores in the overall scale.

CONCLUSION

The results suggest that public health campaigns should take into account the generational differences in COVID-19 vaccination hesitancy to achieve higher levels of vaccine acceptance, including amongst healthcare professionals and students.

IMPACT

Vaccination is the most effective strategy to tackle the COVID-19 pandemic. The advice of health professionals strongly influences vaccination willingness in the general population. A consideration of the generational patterns in the COVID-19 vaccination hesitancy of healthcare workers and students may increase vaccination uptake in these populations, which in turn may lead to greater public acceptance of the vaccine.

Understanding hesitancy with revealed preferences across COVID-19 vaccine types

Many countries have secured larger quantities of COVID-19 vaccines than their population is willing to take. The abundance and the large variety of vaccines created not only an unprecedented intensity of vaccine related public discourse, but also a historical moment to understand vaccine hesitancy better. Yet, the heterogeneity of hesitancy by vaccine types has been neglected in the existing literature so far. We address this problem by analysing the acceptance and the assessment of five vaccine types. We use information collected with a nationally representative survey at the end of the third wave of the COVID-19 pandemic in Hungary. During the vaccination campaign, individuals could reject the assigned vaccine to wait for a more preferred alternative that enables us to quantify revealed preferences across vaccine types. We find that hesitancy is heterogenous by vaccine types and is driven by individuals' trusted source of information. Believers of conspiracy theories are more likely to evaluate the mRNA vaccines (Pfizer and Moderna) unacceptable. Those who follow the advice of politicians are more likely to evaluate vector-based (AstraZeneca and Sputnik) or whole-virus vaccines (Sinopharm) acceptable. We argue that the greater selection of available vaccine types and the free choice of the individual are desirable conditions to increase the vaccination rate in societies.

Exploring the Relationship between COVID-19 Vaccine Refusal and Belief in Fake News and Conspiracy Theories: A Nationwide Cross-Sectional Study in Italy

The COVID-19 pandemic has been accompanied by an infodemic, which includes fake news (FNs) and conspiracy theories (CTs), and which may worsen vaccine refusal (VR), thus hindering the control of the transmission. This study primarily aimed to assess COVID-19 VR in Italy and its relationship with belief in FNs/CTs. Secondarily, it explored the conviction in FNs and CTs and associated variables. An online cross-sectional study was conducted in Italy (2021). The primary outcome was VR and secondary outcomes were FN misclassification score (0% to 100%: higher score means higher misclassification) and CT belief score (1 to 5: higher score means higher agreement). There were 1517 participants; 12.3% showed VR. The median FN and CT scores were: 46.7% (IQR = 40–56.7%) and 2.8 (IQR = 2.2–3.4). Age, education, FN, and CT scores had significant associations with VR. Education, economic situation, health and e-health literacy showed significant relationships with secondary outcomes. Study/work background had a significant association only with the FN score. FN and CT scores were associated. This work estimated a VR lower than before the first COVID-19 vaccine approval. The relationship between VR and FN/CT belief represents a new scenario, suggesting the need for planning effective strategies to tackle FNs and CTs to implement successful vaccination campaigns.

Behind the Scenes of COVID-19 Vaccine Hesitancy: Psychological Predictors in an Italian Community Sample

Psychological variables may be crucial in favoring or discouraging health-related behaviors, including vaccine acceptance. This study aimed to extend the previous literature by outlining the psychological profile associated with COVID-19 vaccine hesitancy in a sample of Italian citizens. Between April and May 2021, 1122 Italian volunteers completed a web survey on COVID-19 vaccine acceptance, also including several self-reported psychological measures. A multiple hierarchical logistic regression analysis was performed to identify the psychological variables associated with vaccine hesitancy. Low confidence in COVID-19 vaccine efficacy and safety, low collective responsibility, high complacency, and high calculation (i.e., extensive information searching, and costs–benefit estimates) predicted higher hesitancy. Our results suggest that to be effective, vaccine-related communications should be as clear, understandable, and sound as possible, preventing the spreading of misunderstandings, or even fake information, that may foster people’s insecurities and distrust. Furthermore, the advantages and necessity of vaccination, both at the individual and community-level, should be clearly emphasized. Efficacious vaccine-related communications may be crucial, not only to maintain an adequate immunity rate for COVID-19, but also to inform policymakers and public authorities in the case of possible future infectious outbreaks.

The Role of Existential Concerns in the Individual's Decisions regarding COVID-19 Vaccine Uptake: A Survey among Non-Vaccinated Italian Adults during the Third Wave of the Pandemic

Recent studies have suggested that health constructs embraced by the Terror Management Theory (TMT) and the Basic Psychological Needs Theory (BPNT) may drive individuals' COVID-19 health-related decisions. This study examines the relationships between existential concerns (ECs; within the TMT), basic psychological needs (BPNs; within the BPNT) and COVID-19 vaccine hesitancy (VH), as well as the mediating role of negative attitudes toward COVID-19 vaccines. A cross-sectional survey was carried out from April to May 2021 on a sample of two hundred and eighty-seven adults (Mage = 36.04 ± 12.07; 59.9% females). Participants provided information regarding existential concerns, basic psychological needs, attitudes toward COVID-19 vaccines and vaccine hesitancy for Pfizer-BioNTech and AstraZeneca vaccines separately. Higher vaccine hesitancy (32.1%) and vaccine resistance (32.8%) rates were found for AstraZeneca than for Pfizer-BioNTech COVID-19 vaccine (22.3% and 10.1%, respectively). Structural equation modeling showed that existential concerns were related to Pfizer-BioNTech and AstraZeneca vaccine hesitancy both directly and indirectly through negative attitudes toward potential side effects of COVID-19 vaccines. The findings of the study confirm that the TMT is efficient in explaining COVID-19 vaccine hesitancy. Targeted efforts are needed to increase the acceptance of COVID-19 vaccines.

Bayesian subjectivism and psychosocial attitude toward COVID-19 vaccines

Background: People resistant to vaccination against the coronavirus disease 2019 (COVID-19) pandemic have been counted in almost all countries worldwide. This anti-scientific subjectivity attitude could be explained by assuming as background the individual probability theory originally elaborated by the statistical school of de Finetti. Methods: This research method is based on a sample of 613 subjects from European countries who completed a questionnaire on attitudes towards COVID-19 vaccinations. On a six-value scale, a questionnaire investigated knowledge, assessments, degree of confidence, level of fear, anguish, and anger. Some items proposed an imaginary bet on the probability of not getting sick to deepen the possible presence of subjectivist assumptions about pandemics. Results: 50.4% were against vaccines and 52.5% against the so-called "Green Pass". Results of t-tests and correlations and stepwise regressions indicate that the sample's reasons for opposing vaccination are related to an ego centred vision of the values that assign minor, if any, confidence to authority. Conclusions: This result supports the conclusion that No Vax decisions are more based on subjectivist probabilistic assumptions, thus in line with the significant social trend called "individualism".

Intolerance of Uncertainty and Risk Perception during the COVID-19 Pandemic: The Mediating Role of Fear of COVID-19

The COVID-19 pandemic, a period of uncertainty and risk, has presented a threat to people’s physical and mental health worldwide. Previous research has shown that pandemic-related uncertainty can contribute to individuals’ psychological distress and coping responses. Therefore, the aim of this study was to investigate the relationship between intolerance of uncertainty and risk perception (i.e., individual’s perceived likelihood of becoming infected both for themselves and people in one’s own country and perceived severity of the infection), and the mediating role of fear of COVID-19. This two-wave longitudinal study (T1 = April 2020; T2 = May 2020) involved 486 young adults (age range = 18–29 years; Mage = 23.84 ± 2.94). Participants provided demographic data as well as measures of intolerance of uncertainty, fear of COVID-19, and risk perception. Structural equation modeling showed that intolerance of uncertainty was indirectly related to risk perception through fear of COVID-19. The study confirms the central role of IU in fear management and, consequently, in determining individuals’ risk estimates.

Willingness to Receive a COVID-19 Vaccine and Associated Factors among Older Adults: A Cross-Sectional Survey in Shanghai, China

Background: Older individuals have a high risk of morbidity and mortality due to COVID-19, and one of the most effective ways to prevent COVID-19 is vaccination. Little is known about older people’s willingness to receive a COVID-19 vaccine. Therefore, the objective of this study was to assess the acceptance of and factors influencing the intention to receive a COVID-19 vaccination among older adults in Shanghai, China. Methods: A cross-sectional study was conducted among older adults (≥60 years old) in Shanghai. Face-to-face interviews with a questionnaire were conducted in community health service centers, recording several parameters: demographic information, health-related factors; perceived likelihood, severity, and burden of COVID-19; perceived safety, effectiveness, necessity, and benefit of the COVID-19 vaccine, as well as their trust in the vaccine delivery system and doctors; willingness to receive a COVID-19 vaccination. Bivariate analysis between several survey items and the willingness to receive a COVID-19 vaccination was conducted using a chi-square test. Logistic regression was used to assess to what degree each variable affected the willingness to receive a COVID-19 vaccination. Results: Of the 1067 participants, 90.91% (970/1067) confirmed that they were willing to receive a COVID-19 vaccination. The participants were more likely to be willing to be vaccinated if they were immigrants (OR = 1.988, 95%CI = 1.062−3.717), had an education level of junior high school (OR = 2.724, 95%CI = 1.000−7.423) or high school or above (OR = 3.993, 95%CI = 1.576−10.119), and had a monthly income of CNY 3000−5000 (OR = 32.770, 95%CI = 1.144−6.711) or CNY >5000 (OR = 2.309, 95%CI = 1.003−5.319). The participants were also more likely to be willing to be vaccinated if they had received a pneumonia vaccination previously (OR = 2.138, 95%CI = 1.016−4.500), perceived the safety of the COVID-19 vaccine (OR = 1.508, 95%CI = 1.073−2.119), perceived the necessity of the COVID-19 vaccine (OR = 2.604, 95%CI = 1.946−3.484), or trusted the suggestions of doctors (OR = 1.706, 95%CI = 1.115−2.618). The participants were less likely to be willing to be vaccinated if they were aged ≥76 years (OR = 0.498, 95%CI = 0.264−0.939), reported a physical health condition of bad or below (OR = 0.229, 95% CI = 0.095−0.549), or were worried about the adverse effects of a COVID-19 vaccination (OR = 0.503, 95%CI = 0.364−0.695). Conclusions: Under the free vaccination policy for COVID-19, older adults have a high intention to be vaccinated to prevent COVID-19 in Shanghai, China. Widely publicizing the safety and necessity of COVID-19 vaccination is necessary.

Vaccinating to Protect Others: The Role of Self-Persuasion and Empathy among Young Adults

Direct persuasion is usually less effective than self-persuasion. As research shows that most young adults are unafraid of COVID-19, this study aimed to investigate the effectiveness of self-persuasion targeted at protecting the health of others to encourage young adults to be vaccinated against COVID-19 and examined the link between empathy and vaccination intention. We conducted two studies: Study 1 (n = 352) compared the effectiveness of self-persuasion targeted at others’ health versus personal health and direct persuasion in encouraging COVID-19 vaccination intention; Study 2 (n = 375) investigated the applicability of self-persuasion through a poster framed as an open-ended question. The theory of planned behavior-based tools were used in both studies, and structural equation modeling was conducted. Study 1 found that self-persuasion targeted at others’ health (compared to other forms of persuasion) indirectly affects vaccination intention through utility and social norm beliefs. Higher empathy, utility, social norms, and control beliefs are associated with a greater vaccination intention. Study 2 found that the poster with self-persuasion targeted at others’ health enhanced vaccination intention compared with a direct persuasion poster. Our findings demonstrate that self-persuasion targeted at others’ health can potentially increase COVID-19 vaccination uptake among young adults.

Vaccine Hesitancy Under the Magnifying Glass: A Systematic Review of the Uses and Misuses of an Increasingly Popular Construct

Resistance to vaccines has hindered attempts to contain and prevent outbreaks of infectious diseases for centuries. More recently, however, the term "vaccine hesitancy" has been used to describe not necessarily outright resistance but also a delay in acceptance or uncertainty regarding vaccines. Given concerns about hesitancy and its impact on vaccine uptake rates, researchers increasingly shifted the focus from resistance to vaccines toward vaccine hesitancy. Acknowledging the urgency to accurately assess the phenomenon, it is critical to understand the state of the literature, focusing on issues of conceptualization and operationalization. To carry out this systematic review, we collected and analyzed all published empirical articles from 2000 to 2021 that explicitly included quantitative self-report measures of vaccine hesitancy (k = 86). Using a mixed-method approach, the review demonstrates and quantifies crucial inconsistencies in the measurement of the construct, lack of clarity in regard to the determination of who should or should not be defined as hesitant, and overreliance on unrepresentative samples. Crucially, our analysis points to a potential systematic bias toward exaggerating the level of hesitancy in the population. Modeling a vaccine hesitancy co-citation network, the analysis also points to the existence of insular academic silos that make it harder to achieve a unified measurement tool. Theoretical and practical implications for academics, practitioners, and policymakers are discussed.

Communication about vaccine efficacy and COVID-19 vaccine choice: Evidence from a survey experiment in the United States

While mass vaccination campaigns against COVID-19 have inoculated almost 200 million Americans and billions more worldwide, significant pockets of vaccine hesitancy remain. Research has firmly established that vaccine efficacy is an important driver of public vaccine acceptance and choice. However, current vaccines offer widely varying levels of protection against different adverse health outcomes of COVID-19. This study employs an experiment embedded on a survey of 1,194 US adults in June 2021 to examine how communications about vaccine efficacy affect vaccine choice. The experiment manipulated how vaccine efficacy was defined across four treatments: (1) protection against symptomatic infection; (2) protection against severe illness; (3) protection against hospitalization/death; (4) efficacy data on all three metrics. The control group received no efficacy information. Subjects were asked to choose between a pair of vaccines-a one-dose viral vector vaccine or two-dose mRNA vaccine-whose efficacy data varied across the four experimental treatment groups. Efficacy data for each vaccine on each dimension were adapted from clinical trial data on the Johnson & Johnson/Janssen and Pfizer/BioNTech vaccines. Among all respondents, only modest preference gaps between the two vaccines emerged in the control group and when the two vaccines' roughly equivalent efficacy data against hospitalization and death were reported. Strong preferences for a two-dose mRNA vaccine emerged in treatments where its higher efficacy against symptomatic or severe illness was reported, as well as in the treatment where data on all three efficacy criteria were reported. Unvaccinated respondents preferred a one-dose viral vector vaccine when only efficacy data against hospitalization or death was presented. Black and Latino respondents were significantly more likely to choose the one-shot viral vector vaccine in the combined efficacy treatment than were whites. Results speak to the importance of understanding how communications about vaccine efficacy affect public preferences in an era of increasing uncertainty about efficacy against variants.

COVID-19 Parental Vaccine Hesitancy in Romania: Nationwide Cross-Sectional Study

Background: COVID-19 vaccination started in Romania in December 2020. Child vaccination started in 2021 with children aged 12–15 years in August. For children aged 5–11 years, vaccination started in January 2022. The aim of our study was to describe COVID-19 vaccination hesitancy in Romanian children and vaccine acceptability in the general population. As parental consent is required for child vaccination in Romania, these aspects have a significant association. Methods: An analytical cross-sectional survey was conducted in October and November 2021 during the peak of the 4th COVID-19 wave. Results: After validation, 1645 participants formed the main study group: median age 35 years, 72.83% women, and 35.44% from the medical domain. In total, 1311 (79.70%) participants were vaccinated against COVID-19 and 188 (11.42%) had vaccinated their 12–18-year-old children against COVID-19. Parents’ level of education, geographic area of residence, and COVID-19 vaccination status were significantly associated with COVID-19 vaccination. The hesitancy factors of child vaccination included the novelty of COVID-19 vaccines (62, 47.32%), fear of adverse reactions (32, 24.42%), and anti-vaccinism in general (29, 22.13%). In the studied group, only 188 (11.42%) participants recommended vaccination of 5–11-year-old children. Vaccine acceptability was higher in the general population (1311, 79.70%) than in the medical domain (326 out of 583, 55.91%). General vaccine hesitancy was based mainly on beliefs regarding inefficiency (131, 39.22%) and fears about the side effects of the vaccine (76, 22.75%). Conclusions: Overall, the acceptability of COVD-19 vaccines in the Romanian population was influenced by the level of education, area of residence, and being a COVID-19-vaccinated parent. Public health intervention programs are essential.

Estimating data-driven coronavirus disease 2019 mitigation strategies for safe university reopening

After one pandemic year of remote or hybrid instructional modes, universities struggled with plans for an in-person autumn (fall) semester in 2021. To help inform university reopening policies, we collected survey data on social contact patterns and developed an agent-based model to simulate the spread of severe acute respiratory syndrome coronavirus 2 in university settings. Considering a reproduction number of R0 = 3 and 70% immunization effectiveness, we estimated that at least 80% of the university population immunized through natural infection or vaccination is needed for safe university reopening with relaxed non-pharmaceutical interventions (NPIs). By contrast, at least 60% of the university population immunized through natural infection or vaccination is needed for safe university reopening when NPIs are adopted. Nevertheless, attention needs to be paid to large-gathering events that could lead to infection size spikes. At an immunization coverage of 70%, continuing NPIs, such as wearing masks, could lead to a 78.39% reduction in the maximum cumulative infections and a 67.59% reduction in the median cumulative infections. However, even though this reduction is very beneficial, there is still a possibility of non-negligible size outbreaks because the maximum cumulative infection size is equal to 1.61% of the population, which is substantial.

Multilevel determinants of COVID-19 vaccination hesitancy in the United States: A rapid systematic review

Vaccine hesitancy is a challenge for the success and optimal implementation of COVID-19 immunization programs in the US. The objective of this study was to summarize multilevel determinants of COVID-19 vaccination intention in the US to inform future intervention opportunities. To this end, we conducted a rapid systematic review by searching published articles via PubMed published by October 5, 2021, following the PRISMA guidelines. One hundred and six articles were included. According to nationally representative studies, the overall COVID-19 acceptance rate ranges from 53.6% to 84.4%. Individual (demographics, health history, behaviors and health beliefs), interpersonal (having a close friend/family member impacted by COVID-19), healthcare and societal level factors (healthcare provider recommendations, source/credential of COVID-19 related information, and COVID-19 related conspiracy theories) all contributed to COVID-19 vaccine hesitancy in the US. This study demonstrates that the acceptance to COVID-19 vaccines is influenced by various factors, particularly the role of healthcare providers in enhancing public intent to vaccination. Potential interventions to mitigate people's concerns over the vaccines and address vaccine-related conspiracy/misinformation from social media are also critical to encourage vaccine uptake in the US.

Anguish and fears about attitude towards Covid-19 vaccines: contrasts between yes and no vax

The present research investigates the possible causes of resistance to vaccination against the COVID-19 virus. A significant percentage of different countries' populations is refractory to being vaccinated (i.e., in October 2021, in Italy, 20% aged 40–50 years old). A 92-item questionnaire was filled in by a sample of 613 subjects, of which 50.4% said they were against COVID-19 vaccines (63.1% female). Guided by the hypothesis that emotionality constitutes a basis of pre-reflective judgment, items relating to fear, anger and anguish were introduced in the survey. The subjects compiled the Difficulties in Emotional Regulation Scale. The differences between the means of the two samples evaluated with the Student test show that it is, above all, the underlying anguish that constitutes the primary discriminant between the two samples. No Vax mainly considers external the sources of anguish, while Yes Vax sources of anguish appear more internal. From this result an interpretation is advanced: it seems more difficult for No Vax to trust authority recommendations/obligations to get vaccinated because anguish is located just outside the one's body, where Authority dominates.

COVID-19 Vaccine Acceptance of Pregnant and Lactating Women (PLW) in Czechia: An Analytical Cross-Sectional Study

Pregnant and lactating women (PLW) represent a particular population subset with increased susceptibility for COVID-19 morbidity and mortality, even though the evidence about the safety and efficacy of COVID-19 vaccines was delayed due to their initial exclusion from development trials. This unclear situation could have led to increased COVID-19 vaccine hesitancy levels among PLW; therefore, this study aimed to evaluate the attitudes of Czech PLW towards COVID-19 vaccines and the determinants of their attitudes. An analytical cross-sectional survey-based study was carried out in the University Hospital Brno (South Moravia, Czechia) between August and October 2021. The study utilised a self-administered questionnaire (SAQ) adapted from previous instruments used for the same purpose. The SAQ included closed-ended items covering demographic characteristics, clinical and obstetric characteristics, attitudes towards COVID-19 vaccination, and potential psychosocial predictors of vaccine acceptance. Out of the 362 included participants, 278 were pregnant (PW) and 84 were lactating women (LW). The overall COVID-19 vaccine acceptance (immediate and delayed) level was substantially high (70.2%), with a significant difference between PW (76.6%) and LW (48.8%). Out of the 70.2% who agreed to receive the vaccine, 3.6% indicated immediate acceptance, and 66.6% indicated delayed acceptance. Only 13.3% of the participants indicated their acceptance of their physician's vaccination recommendation during pregnancy or while lactating, and 62.2% were against it. Our results agreed with the recent studies that revealed that PW tended to have a high level of COVID-19 vaccine acceptance, and they were also inclined to resist professional recommendations because they predominantly preferred to delay their vaccination. The pregnancy trimester, education level, employment status, and previous live births were significant determinants for COVID-19 vaccine acceptance. The most commonly preferred vaccine type was mRNA-based vaccines, followed by viral vector-based and inactivated virus vaccines. The first top priority of PLW was vaccine safety for their children, followed by vaccine safety for the PLW and vaccine effectiveness. Regarding psychosocial predictors, media/social media, trust in the government, the pharmaceutical industry, and healthcare professionals, partners, and a positive risk-benefit ratio were significant promoters for COVID-19 vaccine acceptance. Findings from this study suggest that promotional interventions targeting PLW should use web platforms and focus on vaccine safety evidence, the expected benefits of vaccines and potential harms of the infection.

COVID-19 Vaccine Booster Hesitancy (VBH) of Healthcare Workers in Czechia: National Cross-Sectional Study

The emerging SARS-CoV-2 variants and waning vaccine-elicited immunity are two public health challenges that occurred simultaneously and synergistically during the summer of 2021 and led to a surging demand for COVID-19 vaccine booster dose (BD) rollout. This study aimed to evaluate the COVID-19 vaccine booster hesitancy (VBH) among Czech healthcare workers to explore the potential determinants of VBH. A national cross-sectional survey-based study was carried out between 3 and 11 November 2021, using an online self-administered questionnaire (SAQ) that explored the participants' demographic characteristics, COVID-19 infection and vaccine anamneses, willingness to receive COVID-19 vaccine BD, and the psychosocial drivers of VBH. A total of 3454 HCW properly responded to the online SAQ, of which 80.9% were females, 30.3% were medical professionals, and 50.5% were ≤47 years old. Most of the participants were already inoculated against SARS-CoV-2 (95.2%), and BTN162b2 was the most commonly administered vaccine (90.7%). As the study sample was planned to represent the target population, it revealed a high level of BD acceptance (71.3%) among Czech HCW, while 12.2% were still hesitant and 16.6% were against the currently available BD. These results are consistent with other recent results from central Europe. Medical professional, male, and older participants were more likely to accept BD rather than allied health professional, female, and younger participants. The BDs' perceived effectiveness against severe illness, symptomatic infection, and community transmission was a significant and strong predictor for BD acceptance, while the effectiveness against the circulating variants was not that important for our target population. The BDs' perceived safety and ethical dilemmas of vaccine justice should be addressed sufficiently while communicating with HCW and other population groups. The altruistic reasons for BD acceptance, i.e., family protection, patient protection, and community health protection, underpin the recommendation of postponing the COVID-19 vaccine mandating in favour of stressing these altruistic concerns amid public health messaging.

COVID-19 Delta Variant: Perceptions, Worries, and Vaccine-Booster Acceptability among Healthcare Workers

Background: As the COVID-19 Delta variant has spread across the globe, healthcare workers' (HCWs) knowledge, worries, and vaccine booster acceptance should be assessed. Methods: Online questionnaires aimed at HCWs in Saudi Arabia were distributed between 9 and 12 August 2021, aiming to evaluate HCWs' perceptions and worries about the Delta variant as well as their feelings about receiving a booster-vaccine. Results: A total of 1279 HCWs participated, with 51.1% being physicians and 41.7% nurses. 92.5% were aware of the emergence of the Delta variant. Still, only 28.7% were found to have sufficient knowledge of the variant, and their level of worry about it was higher than their level of worry about the Alpha variant (2.32/5 versus 1.79/5). The main information sources cited by the participants were social media (50.5%), while 30.5% used scientific journals. Overall, 55.3% were willing to receive a vaccine booster, while one third would have preferred to receive a new mRNA vaccine specifically developed for the Delta variant. Factors associated with vaccine booster acceptance were receiving both vaccination doses (p = 0.008), believing that the Pfizer-BioNTech BNT162b2 vaccine is effective against variants (p < 0.001), and agreement that mixing/matching vaccines is effective against variants (p < 0.001). Conclusions: A high percentage of HCWs were aware of the Delta variant, but only a small fraction had decent quality of knowledge about it. The participants exhibited high worry levels and showed a modest acceptance of receiving a vaccine booster dose. These results should encourage public health officials to scale up educational efforts to disseminate reliable information about the different variants and provide recommendations about receiving a vaccine booster. Further research on methods to alleviate HCWs' worries about emerging variants is warranted.

COVID-19 Vaccine Hesitancy among Italian University Students: A Cross-Sectional Survey during the First Months of the Vaccination Campaign

Achieving high levels of vaccination coverage against COVID-19 may be hindered by vaccine hesitancy. We quantified over time the prevalence of COVID-19 vaccine hesitancy among university students, investigated its determinants, and analyzed student attitudes, risk perceptions and compliance with preventive measures. The survey was administered online from 1 March to 30 June 2021. A multivariable logistic regression model was built to identify predictors of hesitancy. Overall, we collected 5369 questionnaires that were grouped into three survey periods (March, April-May, and May-June). The response rate ranged from 81.2% to 76.4%, whereas vaccine hesitancy ranged from 22% to 29%. Multivariable analysis showed that April-May participants had higher odds of hesitancy than March respondents. Other positive predictors were being male, not being a healthcare student, having a lower academic level, and not disclosing a political position. Conversely, higher levels of perceived COVID-19 severity, concern for the emergency, confidence in vaccine safety and effectiveness, and self-reported adherence to mask wearing indoors and outdoors were negatively associated with hesitancy. We found that vaccine hesitancy changed over time and in relation to several factors. Strategies aimed at increasing the students' awareness and engagement, restoring confidence in health authorities, and limiting disinformation around the vaccines should be devised.

COVID-19 Vaccine Hesitancy among the Younger Generation in Japan

Japan has vaccinated its older population; a mass vaccination program for younger citizens is underway. Accordingly, this study investigated vaccine hesitancy among younger Japanese citizens. We used online panel survey data from the Hiroshima Institute of Health Economics Research of Hiroshima University and applied probit regression models. Our study found that vaccine hesitancy among younger people was significantly higher than among older people. Moreover, vaccine hesitancy was significantly higher among younger women than younger men and inter-age-group differences in vaccine hesitancy were higher for younger men than for younger women. Regression demonstrated that subjective health status and anxiety about the future were significantly associated with vaccine hesitancy among younger women and younger men of all ages, respectively. Furthermore, marital status, university degree, anxiety about the future, and myopic view of the future had specific associations with vaccine hesitancy among younger women of different ages, while subjective health status, university degree, having children, financial literacy, household income and assets, and myopic view about the future had specific associations with vaccine hesitancy among younger men of varying ages. Therefore, these results suggest that policymakers should consider the diversity among the younger generation while developing effective, tailored communication strategies to reduce their vaccine hesitancy.