The intention to get vaccinated against influenza and actual vaccination uptake of Dutch healthcare personnel

Exploring vaccine hesitancy and acceptance in the general population of Pakistan: Insights into COVID-19-related distress, risk perception, and stigma

The coronavirus disease 2019 (COVID-19) caused several impacts. Focusing on 360 participants (178 males, 182 females), this study explored the association between COVID-19 related distress, risk perception, stigma, and vaccine hesitancy and acceptance in the general population. Measures used included the Hospital Anxiety and Depression Scale (HADS) and COVID Stress Scale (CSS) to evaluate anxiety, depression, and COVID-19 related distress, the COVID-19 Risk Perception Scale and COVID-19 Stigma Discrimination Scale to assess risk perception and stigma, and the Oxford COVID-19 Vaccine Hesitancy Scale and Vaccine Acceptance Instrument to measure vaccine hesitancy and acceptance. The findings revealed that 66.9% of participants exhibited vaccine hesitancy, and stress and risk perception were significant predictors of both vaccine hesitancy and acceptance, even after controlling for demographic factors. This study highlights the importance of understanding the factors mentioned above that will contribute to vaccine hesitancy and acceptance, which will contribute to promoting vaccine acceptance.

Trust in institutions affects vaccination campaign outcomes

BACKGROUND

Trust is an important driver of various outcomes, but little is known about whether trust in institutions affects actual vaccination campaign outcomes rather than only beliefs and intentions.

METHODS

We used nationally representative, individual-level data for 114 countries and combined them with data on vaccination policies and rates. We measured the speed of the vaccination campaign for each country using the estimated growth rate of a Gompertz curve. We then performed country-level regressions in the global sample and explored heterogeneity across World Bank development groups.

RESULTS

Globally, higher trust in institutions significantly increased vaccination rates (p<0.01) and vaccination speed (p<0.01). The effect was strong in low- and middle-income countries but statistically not significant in high-income countries.

CONCLUSIONS

Our findings have implications for the design of vaccination campaigns for national governments and international organizations. The findings highlight the importance of trust in institutions when designing communication strategies around vaccination campaigns in low- and middle-income countries.

Survival Analysis and Socio-Cognitive Factors in the Timing of COVID-19 Vaccination Among Mexican-Origin Youth

OBJECTIVE

The COVID-19 pandemic disproportionately affected ethnic minority populations and exacerbated preexisting health disparities. The current study aims to promote vaccine uptake among Mexican-origin youth from immigrant families by examining their time to COVID-19 vaccine uptake and assessing the influence of demographic, cognitive, and social factors on the incidence of COVID-19 vaccination.

METHODS

The study conducted Survival Analysis using a Cox proportional hazards model based on a sample of 202 Mexican-origin youth (61.39% female; Mage = 20.41) with data collected from August 2021 to January 2023 in central Texas.

RESULTS

The results show a critical time period for vaccine uptake (i.e., in the first six months after the vaccines were publicly available), evidenced by a surge decrease in COVID-19 unvaccination probability. In addition, more positive attitudes toward the COVID-19 vaccine (Hazard ratio/HR = 1.89, 95% Confidence Interval/CI = [1.64, 2.18]), greater motivation (HR = 2.29, 95% CI = [1.85, 2.85]), higher education levels (HR = 1.52, 95% CI = [1.24, 1.86]), and fewer general barriers to COVID-19 vaccine knowledge (HR = 0.75, 95% CI = [0.60, 0.94]) were associated with greater incidences of receiving COVID-19 vaccines at any given time point during the pandemic.

CONCLUSION

The findings suggest that COVID-19 vaccine uptake among Mexican-origin youth occurred primarily within the initial months of vaccines being publicly distributed. To encourage vaccination among Mexican-origin youth, sustained COVID-19 vaccine promotion efforts are needed by targeting their motivation and positive attitudes and reducing barriers to vaccine information, particularly for youth with lower education levels.

Testing an extended theory of planned behaviour in predicting Covid-19 vaccination intention over the course of the pandemic: A three-wave repeated cross-sectional study

Background

Mass vaccination against Covid-19 has been recognised as the most effective strategy for overcoming the pandemic emergency and remains crucial in the ongoing efforts to mitigate the impact of the virus. The present study aimed to test the efficacy of an extended Theory of Planned Behaviour (TPB) model in predicting vaccination intention in three different phases of the pandemic. Understanding how psychological drivers of vaccine acceptance may have changed throughout the pandemic is essential for informing public health strategies and addressing vaccine hesitancy, even in the current post-pandemic context.

Methods

Using a repeated cross-sectional survey, we tested the hypothesised extended TPB model (intention, attitude, subjective norms, perceived behavioural control, anticipated affective reactions, risk perception, trust in science, trust in institutions and religiosity) across three independent samples: before (T1: November-December 2020; N = 657), during (T2: March-May 2021; N = 818), and after (T3: February-March 2022; N = 605) the start of the vaccination campaign in Italy.

Results

Results indicated significant differences between the time points in all investigated variables, pointing to a general trend of improvement in vaccine acceptability levels at T2 compared to T1, and a worsening at T3 compared to the other two time points. Interestingly, net of these differences, a multi-group Structural Equation Modeling analysis supported the invariance, across time, of the structural relationships examined within the extended TPB.

Conclusion

Findings demonstrated the efficacy of the TPB in predicting Covid-19 vaccination intention at different stages of the pandemic, suggesting that the model, in its extended version, represents a valuable framework for designing interventions aimed at promoting vaccine acceptance.

Interventions to increase vaccination against COVID-19, influenza and pertussis during pregnancy: a systematic review and meta-analysis

BACKGROUND

Pregnant women and their babies face significant risks from three vaccine-preventable diseases: COVID-19, influenza and pertussis. However, despite these vaccines' proven safety and effectiveness, uptake during pregnancy remains low.

METHODS

We conducted a systematic review (PROSPERO CRD42023399488; January 2012-December 2022 following PRISMA guidelines) of interventions to increase COVID-19/influenza/pertussis vaccination in pregnancy. We searched nine databases, including grey literature. Two independent investigators extracted data; discrepancies were resolved by consensus. Meta-analyses were conducted using random-effects models to estimate pooled effect sizes. Heterogeneity was assessed using the I2 statistics.

RESULTS

From 2681 articles, we identified 39 relevant studies (n = 168 262 participants) across nine countries. Fifteen studies (39%) were randomized controlled trials (RCTs); the remainder were observational cohort, quality-improvement or cross-sectional studies. The quality of 18% (7/39) was strong. Pooled results of interventions to increase influenza vaccine uptake (18 effect estimates from 12 RCTs) showed the interventions were effective but had a small effect (risk ratio = 1.07, 95% CI 1.03, 1.13). However, pooled results of interventions to increase pertussis vaccine uptake (10 effect estimates from six RCTs) showed no clear benefit (risk ratio = 0.98, 95% CI 0.94, 1.03). There were no relevant RCTs for COVID-19. Interventions addressed the 'three Ps': patient-, provider- and policy-level strategies. At the patient level, clear recommendations from healthcare professionals backed by text reminders/written information were strongly associated with increased vaccine uptake, especially tailored face-to-face interventions, which addressed women's concerns, dispelled myths and highlighted benefits. Provider-level interventions included educating healthcare professionals about vaccines' safety and effectiveness and reminders to offer vaccinations routinely. Policy-level interventions included financial incentives, mandatory vaccination data fields in electronic health records and ensuring easy availability of vaccinations.

CONCLUSIONS

Interventions had a small effect on increasing influenza vaccination. Training healthcare providers to promote vaccinations during pregnancy is crucial and could be enhanced by utilizing mobile health technologies.

Beyond intention: Predicting children's COVID-19 vaccine uptake using the theory of planned behavior

This prospective study tested if parental factors from the theory of planned behavior (TPB) predicted children's uptake of the COVID-19 vaccine and examined whether parents' intention to vaccinate children against COVID-19 would mediate such associations. Participants were 852 Hong Kong parents of 1076 children aged 5-12. At Time 1, parents reported on items measuring the TPB predictors (i.e. attitudes, subjective norms, and perceived behavioral control) and intention. At Time 2 (approximately 4 months after Time 1), parents reported whether their children had received the COVID-19 vaccine. Attitudes, perceived behavioral control, and intention predicted children's actual uptake of the COVID-19 vaccine. Intention mediated the relations between two TPB predictors, namely attitudes and subjective norms, and children's COVID-19 vaccination uptake. The TPB is considered a useful framework in the development of future COVID-19 vaccine programs for children to promote parents' intention and the subsequent uptake of the COVID-19 vaccine among children.

Intent to vaccinate against SARS-CoV-2 and its determinants across six ethnic groups living in Amsterdam, the Netherlands: A cross-sectional analysis of the HELIUS study

BACKGROUND

Ethnic minority groups experience a disproportionately high burden of infections, hospitalizations and mortality due to COVID-19, and therefore should be especially encouraged to receive SARS-CoV-2 vaccination. This study aimed to investigate the intent to vaccinate against SARS-CoV-2, along with its determinants, in six ethnic groups residing in Amsterdam, the Netherlands.

METHODS

We analyzed data of participants enrolled in the population-based multi-ethnic HELIUS cohort, aged 24 to 79 years, who were tested for SARS-CoV-2 antibodies and answered questions on vaccination intent from November 23, 2020 to March 31, 2021. During the study period, SARS-CoV-2 vaccination in the Netherlands became available to individuals working in healthcare or > 75 years old. Vaccination intent was measured by two statements on a 7-point Likert scale and categorized into low, medium, and high. Using ordinal logistic regression, we examined the association between ethnicity and lower vaccination intent. We also assessed determinants of lower vaccination intent per ethnic group.

RESULTS

A total of 2,068 participants were included (median age 56 years, interquartile range 46-63). High intent to vaccinate was most common in the Dutch ethnic origin group (369/466, 79.2%), followed by the Ghanaian (111/213, 52.1%), South-Asian Surinamese (186/391, 47.6%), Turkish (153/325, 47.1%), African Surinamese (156/362, 43.1%), and Moroccan ethnic groups (92/311, 29.6%). Lower intent to vaccinate was more common in all groups other than the Dutch group (P < 0.001). Being female, believing that COVID-19 is exaggerated in the media, and being < 45 years of age were common determinants of lower SARS-CoV-2 vaccination intent across most ethnic groups. Other identified determinants were specific to certain ethnic groups.

CONCLUSIONS

Lower intent to vaccinate against SARS-CoV-2 in the largest ethnic minority groups of Amsterdam is a major public health concern. The ethnic-specific and general determinants of lower vaccination intent observed in this study could help shape vaccination interventions and campaigns.

The impact of side effect framing on COVID-19 booster vaccine intentions in an Australian sample

OBJECTIVE

To evaluate the effect of presenting positively attribute-framed side effect information on COVID-19 booster vaccine intention relative to standard negatively-framed wording and a no-intervention control.

DESIGN AND PARTICIPANTS

A representative sample of Australian adults (N = 1204) were randomised to one of six conditions within a factorial design: Framing (Positive; Negative; Control) × Vaccine (Familiar (Pfizer); Unfamiliar (Moderna)).

INTERVENTION

Negative Framing involved presenting the likelihood of experiencing side effects (e.g., heart inflammation is very rare, 1 in every 80,000 will be affected), whereas Positive Framing involved presenting the same information but as the likelihood of not experiencing side effects (e.g., 79,999 in every 80,000 will not be affected).

PRIMARY OUTCOME

Booster vaccine intention measured pre- and post-intervention.

RESULTS

Participants were more familiar with the Pfizer vaccine (t(1203) = 28.63, p <.001, Cohen's d_z = 0.83). Positive Framing (M = 75.7, SE = 0.9, 95% CI = [73.9, 77.4]) increased vaccine intention relative to Negative Framing (M = 70.7, SE = 0.9, 95% CI = [68.9, 72.4]) overall (F(1, 1192) = 4.68, p =.031, η_p² = 0.004). Framing interacted with Vaccine and Baseline Intention (F(2, 1192) = 6.18, p =.002, η_p² = 0.01). Positive Framing was superior, or at least equal, to Negative Framing and Control at increasing Booster Intention, irrespective of participants' pre-intervention level of intent and vaccine type. Side effect worry and perceived severity mediated the effect of Positive vs. Negative Framing across vaccines.

CONCLUSION

Positive framing of side effect information appears superior for increasing vaccine intent relative to the standard negative wording currently used.

PRE-REGISTRATION

See: aspredicted.org/LDX_2ZL.

Knowledge, attitudes, perceptions, and practice toward seasonal influenza and its vaccine: A cross-sectional study from a country of conflict

Background

The seasonal influenza vaccine is an important preventive measure against influenza and its associated complications. In Yemen, there is no seasonal influenza vaccination policy, and the influenza vaccine is excluded from the national immunization program. Data on vaccination coverage remain scarce with no previous surveillance programs or awareness campaigns implemented in the country. The current study aims to assess the awareness, knowledge, and attitudes of the public in Yemen toward seasonal influenza and their motivators and perceived barriers to receiving its vaccine.

Methods

A cross-sectional survey was carried out using a self-administered questionnaire that was distributed to eligible participants using convenience sampling.

Results

A total of 1,396 participants completed the questionnaire. The respondents showed a median knowledge score of influenza of 11.0/15.0, and most of them (70%) were able to recognize its modes of transmission. However, only 11.3% of the participants reported receiving the seasonal influenza vaccine. Physicians were the respondents' most preferred information source for influenza (35.2%), and their recommendation (44.3%) was the most cited reason for taking its vaccine. On the contrary, not knowing about the vaccine's availability (50.1%), concerns regarding the safety of the vaccine (17%), and not considering influenza as a threat (15.9%) were the main reported barriers to getting vaccinated.

Conclusion

The current study showed a low uptake of influenza vaccines in Yemen. The physician's role in promoting influenza vaccination seems to be essential. Extensive and sustained awareness campaigns would likely increase the awareness of influenza and remove misconceptions and negative attitudes toward its vaccine. Equitable access to the vaccine can be promoted by providing it free of charge to the public.

Providing normative information increases intentions to accept a COVID-19 vaccine

Despite the availability of multiple safe vaccines, vaccine hesitancy may present a challenge to successful control of the COVID-19 pandemic. As with many human behaviors, people's vaccine acceptance may be affected by their beliefs about whether others will accept a vaccine (i.e., descriptive norms). However, information about these descriptive norms may have different effects depending on the actual descriptive norm, people's baseline beliefs, and the relative importance of conformity, social learning, and free-riding. Here, using a pre-registered, randomized experiment (N = 484,239) embedded in an international survey (23 countries), we show that accurate information about descriptive norms can increase intentions to accept a vaccine for COVID-19. We find mixed evidence that information on descriptive norms impacts mask wearing intentions and no statistically significant evidence that it impacts intentions to physically distance. The effects on vaccination intentions are largely consistent across the 23 included countries, but are concentrated among people who were otherwise uncertain about accepting a vaccine. Providing normative information in vaccine communications partially corrects individuals' underestimation of how many other people will accept a vaccine. These results suggest that presenting people with information about the widespread and growing acceptance of COVID-19 vaccines helps to increase vaccination intentions.

Multifactorial influences underpinning a decision on COVID-19 vaccination among healthcare workers: a qualitative analysis

COVID-19 vaccination in healthcare workers (HCW) is essential for improved patient safety and resilience of health systems. Despite growing body of literature on the perceptions of COVID vaccines in HCWs, existing studies tend to focus on reasons for 'refusing' the vaccines, using surveys almost exclusively. To gain a more nuanced understanding, we explored multifactorial influences underpinning a decision on vaccination and suggestions for decision support to improve vaccine uptake among HCWs in the early phase of vaccination rollout. Semi-structured interviews were undertaken with thirty-three HCWs in Singapore. Transcribed data was thematically analyzed. Decisions to accept vaccines were underpinned by a desire to protect patients primarily driven by a sense of professional integrity, collective responsibility to protect others, confidence in health authorities and a desire to return to a pre-pandemic way of life. However, there were prevailing concerns with respect to the vaccines, including long-term benefits, safety and efficacy, that hampered a decision. Inadequate information and social media representation of vaccination appeared to add to negative beliefs, impeding a decision to accept while low perceived susceptibility played a moderate role in the decision to delay or decline vaccination. Participants made valuable suggestions to bolster vaccination. Our findings support an approach to improving vaccine uptake in HCWs that features routine tracking and transparent updates on vaccination status, use of institutional platforms for sharing of experience, assuring contingency management plans and tailored communications to emphasize the duty of care and positive outlook associated with vaccination.

Drivers of the Intention to Receive a COVID-19 Booster Vaccine: Insights from the UK and Australia

As the global pandemic perpetuates, keeping the population vaccinated will be imperative to maintain societal protection from the SARS-CoV-2 (COVID-19) virus. However, while empirical evidence regarding predictors of the intention to receive a first COVID-19 vaccine has amassed, our understanding regarding the psychological and behavioral drivers of continued COVID-19 vaccination remains limited. In this pre-registered study (UK: AsPredicted#78370|Australia: AsPredicted#81667), factors predicting the intention to receive a COVID-19 booster vaccine were investigated in two adult samples from the UK (N = 1222) and Australia (N = 1197) that were nationally representative on factors of age, gender, and geographic location. High levels of booster intent were found (73% and 67%, respectively). Exploratory Structural Equation Modelling (ESEM) revealed three key predictors of the intention to receive a booster vaccine that emerged across both UK and Australian samples: concern regarding the COVID-19 virus, positive perceptions of the COVID-19 vaccines, and the perceived severity of side effects experienced to the last COVID-19 vaccine dose. Several additional factors (age, months since the last COVID-19 vaccine, familiarity with side effects, and regularly receiving the influenza vaccine) were present in the Australian dataset. These findings provide important evidence that targeting psychological perceptions of the COVID-19 vaccine and virus may serve to maintain participation in the COVID-19 vaccination programme, paving the way for future behavioural research in this area.

Excluding numeric side-effect information produces lower vaccine intentions

Encouraging vaccine uptake is important to reducing the impact of infectious disease. However, negative attitudes and vaccine hesitancy, due in part to worry about side effects, are obstacles to achieving high vaccination rates. Provided vaccine information sheets typically include a list of side effects without numeric information about their likelihoods, but providing such numbers may yield benefits. We investigated the effect of providing numeric information about side-effect likelihood (e.g., "1%") and verbal labels (e.g., "uncommon") on intentions to get a hypothetical vaccine, reasons for the vaccination decision, and risk overestimation. In a diverse, online, convenience sample (N = 595), providing numeric information increased vaccine intentions-70% of those who received numeric information were predicted to be moderately or extremely likely to vaccinate compared to only 54% of those who did not receive numeric information (p<.001), controlling for age, gender, race, education, and political ideology. Participants receiving numeric information also were less likely to overestimate side-effect likelihood. Verbal labels had additional benefits when included with numeric information, particularly among the vaccine hesitant. For these participants, verbal labels increased vaccine intentions when included with numeric information (but not in its absence). Among the vaccine-hesitant, 43% of those provided numeric information and verbal labels were predicted to be moderately or extremely likely to get vaccinated vs. only 24% of those given a list of side effects (p<.001). We conclude that the standard practice of not providing numeric information about side-effect likelihood leads to a less-informed public who is less likely to vaccinate.

Does social influence affect COVID-19 vaccination intention among the unvaccinated?

Conformist social influence is a double-edged sword when it comes to vaccine promotion. On the one hand, social influence may increase vaccine uptake by reassuring the hesitant about the safety and effectiveness of the vaccine; on the other hand, people may forgo the cost of vaccination when the majority is already vaccinated - giving rise to a public goods dilemma. Here, we examine whether available information on the percentage of double-vaccinated people affects COVID-19 vaccination intention among unvaccinated people in Turkey. In an online experiment, we divided participants (n = 1013) into low, intermediate and high social influence conditions, reflecting the government's vaccine promotion messages. We found that social influence did not predict COVID-19 vaccination intention, but psychological reactance and collectivism did. People with higher reactance (intolerance of others telling one what to do and being sceptical of consensus views) had lower vaccination intention, whilst people with higher collectivism (how much a person considers group benefits over individual success) had higher vaccination intention. Our findings suggest that advertising the percentage of double-vaccinated people is not sufficient to trigger a cascade of others getting themselves vaccinated. Diverse promotion strategies reflecting the heterogeneity of individual attitudes could be more effective.

When do persuasive messages on vaccine safety steer COVID-19 vaccine acceptance and recommendations? Behavioural insights from a randomised controlled experiment in Malaysia

INTRODUCTION

Vaccine safety is a primary concern among vaccine-hesitant individuals. We examined how seven persuasive messages with different frames, all focusing on vaccine safety, influenced Malaysians to accept the COVID-19 vaccine, and recommend it to individuals with different health and age profiles; that is, healthy adults, the elderly, and people with pre-existing health conditions.

METHODS

A randomised controlled experiment was conducted from 29 April to 7 June 2021, which coincided with the early phases of the national vaccination programme when vaccine uptake data were largely unavailable. 5784 Malaysians were randomly allocated into 14 experimental arms and exposed to one or two messages that promoted COVID-19 vaccination. Interventional messages were applied alone or in combination and compared against a control message. Outcome measures were assessed as intent to both take the vaccine and recommend it to healthy adults, the elderly, and people with pre-existing health conditions, before and after message exposure. Changes in intent were modelled and we estimated the average marginal effects based on changes in the predicted probability of responding with a positive intent for each of the four outcomes.

RESULTS

We found that persuasive communication via several of the experimented messages improved recommendation intentions to people with pre-existing health conditions, with improvements ranging from 4 to 8 percentage points. In contrast, none of the messages neither significantly improved vaccination intentions, nor recommendations to healthy adults and the elderly. Instead, we found evidence suggestive of backfiring among certain outcomes with messages using negative attribute frames, risky choice frames, and priming descriptive norms.

CONCLUSION

Message frames that briefly communicate verbatim facts and stimulate rational thinking regarding vaccine safety may be ineffective at positively influencing vaccine-hesitant individuals. Messages intended to promote recommendations of novel health interventions to people with pre-existing health conditions should incorporate safety dimensions.

TRIAL REGISTRATION NUMBER

NCT05244356.

Does Vaccinating against Influenza in a Given Epidemic Season Have an Impact on Vaccination in the Next Season: A Follow-Up Study

To improve the uptake of influenza vaccine in the elderly, it is important to understand the factors that predict vaccination. The study objective was to explain influenza vaccination uptake in the next season (2019/2020) in a sample of primary care clinic patients from Gryfino, Poland, vaccinated in 2018/2019 with the free-of-charge quadrivalent vaccine. A baseline and a follow-up survey assessed respondent intentions to receive a vaccine (2018), then (2020) vaccine uptake and its predictors. Patients (n = 108, 54.6% males, Mage = 66.7 ± 6.7) filled in a researcher-administered questionnaire. A majority (69.3%) intended to get vaccinated in the next season, with 25.9% receipt. Of those willing to be immunized, only 31.9% were vaccinated in the next season; of those whose decision was dependent on reimbursement, none received influenza vaccine; of undecided patients, 23.1% were vaccinated. Multivariable analysis indicated that living with a partner (OR 6.22, p = 0.01), being employed (OR = 4.55, p = 0.05) and past vaccination behavior (OR 4.12; p = 0.04) were predictors of vaccine uptake. The findings show limited follow-through on initial influenza vaccination plans for the nearest season in previously vaccinated elderly patients. Future interventions should additionally focus on unanticipated barriers to vaccination, such as those revealed in this study, to increase vaccination coverage rates.

Positive Attribute Framing Increases COVID-19 Booster Vaccine Intention for Unfamiliar Vaccines

Positive framing has been proposed as an intervention to increase COVID-19 vaccination intentions. However, available research has examined fictitious or unfamiliar treatments. This pre-registered study (aspredicted#78369) compared the effect of standard negatively framed EU patient information leaflets (PILs), with new positively framed PILs, on booster intentions (measured pre- and post-intervention) for AstraZeneca, Pfizer, and Moderna COVID-19 vaccines. A representative sample of 1222 UK-based adults was randomised to one of six groups in a factorial design with framing (Positive vs. Negative) and vaccine familiarity (same (as previous), familiar, unfamiliar) as factors. The benefit of positive framing was hypothesised to be strongest for the least familiar vaccine (Moderna). Framing was moderated by familiarity, where only the unfamiliar vaccine showed a benefit of positive relative to negative Framing. Framing and familiarity also interacted with baseline Intention with the effect of framing on the unfamiliar vaccine especially pronounced at low baseline Intent. Conversely, standard negative framing appeared to increase intentions for familiar vaccines at low baseline intent. Findings provide important evidence that positive framing could improve vaccine uptake globally when switches or new developments require individuals to receive less familiar vaccines. Positive framing of familiar vaccines, however, should be treated with caution until better understood.

Effect of COVID-19 Pandemic on Influenza Vaccination Intention: A Meta-Analysis and Systematic Review

Poorer outcomes have been reported with COVID-19 and influenza coinfections. As the COVID-19 pandemic rages on, protection against influenza by vaccination is becoming increasingly important. This study examines how COVID-19 has influenced influenza vaccination intentions from a global perspective. A literature search was conducted on Embase, PubMed, and CNKI from 1 January 2019 to 31 December 2021 for articles reporting rates of influenza vaccination pre-COVID-19 (19/20 season), and intention and/or uptake of influenza vaccination post-COVID-19 (20/21 season). The changes in vaccination intention and reasons for changes were reported. Subgroup analyses were performed by region, gender, age, and occupation. Newcastle Ottawa Scale was used for quality assessment of the articles. Twenty-seven studies with 39,193 participants were included. Among 22 studies reporting intention to vaccinate in 20/21, there was increased intention to vaccinate (RR 1.50, 95% CI 1.32−1.69, p < 0.001) regardless of age, gender, and occupation. The remaining five studies reporting vaccination intention and uptake in 20/21 showed a similar increase (RR 1.68, 95%CI 1.20−2.36). Important determinants include historical vaccine acceptance, and perception of influenza severity and vaccine safety. The COVID-19 pandemic has increased intention to vaccinate against influenza internationally. The pandemic could be a window of opportunity to promote influenza vaccination and decrease vaccine hesitancy.

Lau K, Miraldo M, Hauck K. Bandwagoning, free-riding and heterogeneity in influenza vaccine decisions: An online experiment

'Nudge'-based social norms messages conveying high population influenza vaccination coverage levels can encourage vaccination due to bandwagoning effects but also discourage vaccination due to free-riding effects on low risk of infection, making their impact on vaccination uptake ambiguous. We develop a theoretical framework to capture heterogeneity around vaccination behaviors, and empirically measure the causal effects of different messages about vaccination coverage rates on four self-reported and behavioral vaccination intention measures. In an online experiment, N = 1365 UK adults are randomly assigned to one of seven treatment groups with different messages about their social environment's coverage rate (varied between 10% and 95%), or a control group with no message. We find that treated groups have significantly greater vaccination intention than the control. Treatment effects increase with the coverage rate up to a 75% level, consistent with a bandwagoning effect. For coverage rates above 75%, the treatment effects, albeit still positive, stop increasing and remain flat (or even decline). Our results suggest that, at higher coverage rates, free-riding behavior may partially crowd out bandwagoning effects of coverage rate messages. We also find significant heterogeneity of these effects depending on the individual perceptions of risks of infection and of the coverage rates.

Social conformism and confidence in systems as additional psychological antecedents of vaccination: a survey to explain intention for COVID-19 vaccination among healthcare and welfare sector workers, France, December 2020 to February 2021

BackgroundThe start of the COVID-19 vaccination campaign among French healthcare and welfare sector workers in January 2021 offered an opportunity to study psychological antecedents of vaccination in this group.AimWe explored whether knowledge and attitude items related to social conformism and confidence in systems contributed to explaining intention for COVID-19 vaccination.MethodsWe developed a knowledge and attitude questionnaire with 30 items related to five established and two hypothetical psychological antecedents of vaccination (KA-7C). The online questionnaire was distributed from 18 December 2020 to 1 February 2021 through chain-referral via professional networks, yielding a convenience sample. We used multivariable logistic regression to explore the associations of individual and grouped KA-7C items with COVID-19 vaccine intention.ResultsAmong 5,234 participants, the vaccine intention model fit (pseudo R-squared values) increased slightly but significantly from 0.62 to 0.65 when adding social conformism and confidence in systems items. Intention to vaccinate was associated with the majority opinion among family and friends (OR: 11.57; 95% confidence interval (CI): 4.51-29.67) and a positive perception of employer's encouragement to get vaccinated (vs negative; OR: 6.41; 95% CI: 3.36-12.22). The strongest association of a knowledge item was identifying the statement 'Some stages of vaccine development (testing) have been skipped because of the epidemic emergency.' as false (OR: 2.36; 95% CI: 1.73-3.22).ConclusionThe results suggest that social conformism and confidence in systems are distinct antecedents of vaccination among healthcare and welfare workers, which should be taken into account in vaccine promotion.

Procesos cognitivos implicados en conductas de protección ante COVID-19 (SARS-CoV-2)

Las conductas de riesgo o protección ante enfermedades virales pueden verse influenciadas por la forma como la población construye cogniciones sobre esta realidad, tales cogniciones resultan clave para comprender cómo actúan las personas respecto a situaciones que representan riesgos para su salud. Este estudio evalúa el papel de procesos cognitivos como los sesgos o falsas creencias, la intención conductual y las creencias de eficacia, en relación con la enfermedad COVID-19, procurando determinar su influencia en los comportamientos de protección incluida la probabilidad de vacunarse. A través de un estudio transversal predictivo se evaluó a 794 personas en Colombia durante el primer pico pandémico de 2020, empleando cuestionarios en línea y se construyeron modelos de regresión para pronosticar las conductas de protección recomendadas por la Organización Mundial de la Salud (lavado de manos, aislamiento social, uso de mascarillas). Los hallazgos señalan alta frecuencia en el sesgo de control y el optimismo ilusorio, al igual que altas expectativas de efectividad del cuidado, los cuales pronostican las conductas de protección y la intención de vacunarse. A partir de los resultados se discute que los sesgos relativos al optimismo no necesariamente implican asumir conductas de exposición a la enfermedad, de hecho, parecen tener un papel funcional en el cuidado.

"Would You Get Vaccinated against COVID-19?" The Picture Emerging from a Study on the Prevalence of SARS-CoV-2 Infection in the General Population of the Veneto Region

COVID-19 disease, caused by the SARS-CoV-2 virus, continues to cause high hospitalization and death rates. Vaccination campaigns have been key to controlling the pandemic, but vaccine hesitancy is on the rise. This study investigated the general population’s attitude to vaccination in Veneto (northeast Italy) in January 2021 as part of a study on the prevalence of SARS-CoV-2 infection. An ad hoc questionnaire collected 4467 respondents’ sociodemographic data and propensity to be vaccinated, and findings were analyzed using logistic multivariable regression. The 48.9% of respondents were male, and the mean age was 46.8 ± 16.0 years. Asked whether they would get vaccinated against COVID-19, 84.3% said yes, 5.0% were uncertain, and 10.7% said no. Vaccine acceptance was higher in males than in females (85.8% vs. 82.8%), in people 70+ years old (92.3%), and among people with more than 14 years of schooling (89.6%). Multivariable analysis with adjOR (95% CI) showed a significantly greater vaccine reluctance in females (0.68 (0.57−0.81)), people 30−49 or 50−69 years old (0.69 (0.54−0.87)), and (0.76 (0.58−0.99)); and those with <9 or 9−13 years of schooling (0.62 (0.46−0.82)), and (0.72 (0.57−0.91)). As people refusing vaccination undeniably hinder efforts to control the pandemic, specific strategies are needed to overcome their doubts.

From COVID-19 Vaccination Intention to Actual Vaccine Uptake: A Longitudinal Study Among Chinese Adults After Six Months of a National Vaccination Campaign

BACKGROUND

Mass COVID-19 vaccination campaigns have been launched globally, but the translation from vaccination intention to actual vaccine uptake by the public remains unknown, hindering the evaluation of present promotion strategies.

METHODS

Six months after the national vaccination campaign in China, a longitudinal study was conducted among the Chinese adult population, whose vaccination intention has been previously surveyed, to examine the vaccine uptake, the relationship between intention and actual vaccination, and factors associated with actual vaccination behaviors with multiplelogistic models.

RESULTS

Among the total 1047 participants, 81.8% (834/936) of those who had a prior COVID-19 vaccination intention before the campaign actually received the vaccine, while 61.3% (68/111) of those without a prior intention got vaccinated. Having a prior vaccination intention, believing in vaccine safety and receiving frequent recommendations from community sources were significant predictors of vaccine uptake, while the shortage of vaccine supply would reduce the likelihood of getting vaccinated.

CONCLUSIONS

Promotion interventions for vaccination intentions need to be launched well before the availability of the vaccine. Sustaining vaccination attitudes and intentions, reducing barriers (e.g. vaccine safety concerns, accessibility, affordability) and shaping vaccination behavior would be effective in closing the intention-action gap and motivating vaccine uptake.

Validity and Reliability of a Brief Scale of Intention to Vaccinate Against COVID-19 in a Peruvian Sample

OBJECTIVE

This study aimed to analyze the psychometric properties of a brief scale measuring intention to vaccinate against COVID-19 in a Peruvian sample in the context of the current pandemic.

METHODS

A cross-sectional and instrumental study was carried out. A total of 547 Peruvian citizens selected through non-probability convenience sampling participated. Considering existing theories of vaccination hesitancy, 12 items were proposed that evaluate the intention to vaccinate against COVID-19 and the internal structure was evaluated through exploratory and confirmatory factor analysis. Reliability was analyzed with the ordinal alpha coefficient.

RESULTS

The exploratory factor analysis yielded a structure of 2 oblique factors that explain 69% of the total variance and the items saturated between 0.52 and 0.97. The confirmatory factor analysis showed that, of 4 models analyzed, the fourth model that was composed of 6 items presented optimal indices of goodness-of-fit (X² = 11.089, P = .197, CFI = 0.999, TLI = 0.999, RMSEA = 0.034 [IC 90%, 0.000-0.077], SRMR = 0.016). Reliability analysis through the ordinal alpha coefficient yielded that the brief scale of intention to vaccinate against COVID-19 has adequate internal consistency (α = .91).

CONCLUSIONS

The brief scale of intention to vaccinate against COVID-19 presents adequate psychometric properties that demonstrate validity and reliability and can be used in future research and clinical practice.

The Role of Risk Perception in Students' COVID-19 Vaccine Uptake: A Longitudinal Study

Since COVID-19 vaccine uptake was found to be especially low among young adults, the present study investigated COVID-19 risk perception as predictor of COVID-19 vaccination intention and actual COVID-19 vaccine uptake among this age group. More specifically, it was tested whether cognitive risk perception predicts vaccination uptake successively via affective risk perception and vaccination intention. In total, 680 students (65.9% female) between 17 and 28 years participated in this longitudinal online study. COVID-19 cognitive and affective risk perception, COVID-19 vaccination intention, and actual COVID-19 vaccine uptake were measured in t1: November/December 2020, t2: March 2021, and t3: June/July 2021, respectively. The mediation analysis revealed a significant indirect effect of perceived severity at t1 on vaccine uptake at t3 via worry at t1 and vaccination intention at t2. Stronger perceptions of perceived severity of COVID-19 were related to more worry about COVID-19, which led to a higher vaccination intention, which, in turn, increased the chance of COVID-19 vaccine uptake. To increase vaccine uptake among young adults it might be fruitful to emphasize the severity of COVID-19. However, one should take into account that tapping into fear works best when messages also include efficacy statements.

The seductive allure of technical language and its effect on covid-19 vaccine beliefs and intentions

Previous research has demonstrated a ‘seductive allure’ of technical or reductive language such that bad (e.g., circular) explanations are judged better when irrelevant technical terms are included. We aimed to explore if such an effect was observable in relation to a covid-19 vaccinations and if this subsequently affected behavioural intentions to take up a covid-19 vaccine. Using a between subjects design we presented participants (N = 996) with one of four possible types of vignette that explained how covid-19 vaccination and herd immunity works. The explanations varied along two factors: (1) Quality, explanations were either good or bad (i.e., tautological); (2) Language, explanations either contained unnecessary technical language or did not. We measured participants’ evaluation of the explanations and intentions to vaccinate. We demonstrate a ‘seductive allure’ effect of technical language on bad vaccine explanations. However, an opposite ‘repellent disdain’ effect occurred for good explanations which were rated worse when they contained technical language. Moreover, we show that evaluations of explanations influence intentions to vaccinate. We suggest that misinformation that includes technical language could be more detrimental to vaccination rates. Importantly, however, clear explanatory public health information that omits technical language will be more effective in increasing intentions to vaccinate.

COVID-19 Vaccination: The Mainspring of Challenges and the Seed of Remonstrance

As of March 2020, the time when the coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) became a pandemic, our existence has been threatened and the lives of millions have been claimed. With this ongoing global issue, vaccines are considered of paramount importance in curtailing the outbreak and probably a prime gamble to bring us back to 'ordinary life'. To date, more than 200 vaccine candidates have been produced, many of which were approved by the Food and Drug Administration (FDA) for emergency use, with the research and discovery phase of their production process passed over. Capering such a chief practice in COVID-19 vaccine development, and manufacturing vaccines at an unprecedented speed brought many challenges into play and raised COVID-19 vaccine remonstrance. In this review, we highlight relevant challenges to global COVID-19 vaccine development, dissemination, and deployment, particularly at the level of large-scale production and distribution. We also delineate public perception on COVID-19 vaccination and outline the main facets affecting people's willingness to get vaccinated.

Persuasive messaging to increase COVID-19 vaccine uptake intentions

Widespread vaccination remains the best option for controlling the spread of COVID-19 and ending the pandemic. Despite the considerable disruption the virus has caused to people’s lives, many people are still hesitant to receive a vaccine. Without high rates of uptake, however, the pandemic is likely to be prolonged. Here we use two survey experiments to study how persuasive messaging affects COVID-19 vaccine uptake intentions. In the first experiment, we test a large number of treatment messages. One subgroup of messages draws on the idea that mass vaccination is a collective action problem and highlighting the prosocial benefit of vaccination or the reputational costs that one might incur if one chooses not to vaccinate. Another subgroup of messages built on contemporary concerns about the pandemic, like issues of restricting personal freedom or economic security. We find that persuasive messaging that invokes prosocial vaccination and social image concerns is effective at increasing intended uptake and also the willingness to persuade others and judgments of non-vaccinators. We replicate this result on a nationally representative sample of Americans and observe that prosocial messaging is robust across subgroups, including those who are most hesitant about vaccines generally. The experiments demonstrate how persuasive messaging can induce individuals to be more likely to vaccinate and also create spillover effects to persuade others to do so as well.

The first experiment in this study was registered at clinicaltrials.gov and can be found under the ID number NCT04460703. This study was registered at Open Science Framework (OSF) at: https://osf.io/qu8nb/?view_only=82f06ecad77f4e54b02e8581a65047d7.

Support among healthcare workers for the new mandatory seasonal influenza vaccination policy and its effects on vaccination coverage

INTRODUCTION

Finland was the first European country to introduce a nation-wide mandatory seasonal influenza vaccination policy for healthcare workers (HCWs) by mandating that administrators of health care institutions only employ vaccinated HCWs. In this study, we examine the effects of the new policy and the view of HCWs on the new policy.

METHODS

A cross-sectional observational study was conducted in Kuopio University Hospital among HCWs working in close patient contact. The statistics on vaccination coverage were obtained from the hospital's own databases, where employees were asked to self-report their suitability for work. An anonymous survey was sent to HCWs in 2015-2016 (n = 987) and 2018-2019 (n = 821).

RESULTS

Vaccination coverage increased from 59.5 to 99.6%, according to the hospital's own records. Among the survey respondents, the seasonal influenza vaccination coverage of HCWs increased from 68.2 to 95.4%. 83.8% of doctors and 49.4% of nurses supported the new policy. 12.7% of doctors and 41.5% of nurses found the new mandate coercive or that it restricted their self-determination.

CONCLUSIONS

Our study confirms the positive effects of mandating the administrators of health care institutions to only employ vaccinated HCWs. The majority (57.9%) of all HCWs supported the new policy, with doctors being more compliant than nurses. Key messages Finland became the first European country to mandate influenza vaccination for HCWs by mandating that administrators of health care institutions only employ vaccinated HCWs. After the new act, the vaccination coverage of HCWs increased close to 100%. Most of the HCWs supported the new act and did not find it coercive.

Health worker recommended vaccination rates among medical students in Brazil

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Medical students are a risk population for many infectious diseases, which leads to their being included in health-staff vaccination recommendations.

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There is an increasing noncompliance with vaccination programs, especially in the last decade, which can have also affected medical students’ immunization status and personal beliefs about this theme. Few studies have gauged student awareness of these programs and their effect in vaccination status along the medical course.

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After being submitted to an electronic questionnaire, 74,7% Brazilian students were found to have incomplete vaccination in some way, with Pertussis, Varicella, and Influenza as the highest noncompliance rates. There was an increase in vaccination status toward the end of the course, though still far from optimal.

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Main reasons given not to vaccinate were vaccination hesitancy (for influenza and varicella), and lack of awareness of the need to vaccinate (for pertussis).

Health workers are a risk population for many infectious diseases, which leads to a number of vaccines being routinely recommended for health care staff. Medical students are also prone to such hazards. This study accesses undergraduate medicine students’ compliance to recommended health-staff vaccination, and their reasons for noncompliance.

Method

An online questionnaire was sent to all undergraduates in a major public medical school in Brazil, asking about vaccination status to Hepatitis B, Measle-mumps-rubella, Varicella, Pertussis and Influenza, and reasons in case of noncompliance

Results

146 students answered the questionnaire, (response rate 14,6%). Overall vaccination status showed 74,7% of students with incomplete vaccination in some way, with an increase in vaccination status toward the end of the course. The highest noncompliance rates were Pertussis (49,3%), Varicella (47,3%) and Influenza (30,1%) vaccines. The vaccine with the lowest noncompliance rate was measles (9,6%). During the course, the greatest increases in adequate vaccination status were Hepatitis B, from 53,2% in first-years to 93,2% by the end sixth year (chi-sq 21, p < 0,0001), and Influenza, from 48,9% to 91,5% (chi-sq 22,5, p < 0,00009). Main reasons given not to vaccinate were vaccination hesitancy for influenza and varicella (respectively 61% and 46%), and lack of awareness of the need to vaccinate for pertussis (53%).

Conclusions

Overall vaccine coverage in medical students in Brazil is still far from optimal. There is a markedly high level of vaccine hesitancy and unawareness of need to vaccinate for some diseases, particularly pertussis and influenza.

Clinical trial registry (Brazilian regulation boards): 24159119.3.0000.0065.

Willingness to Vaccinate Against COVID-19: The Role of Health Locus of Control and Conspiracy Theories

Understanding the predictors of the willingness to get vaccinated against COVID-19 may aid in the resolution of current and future pandemics. We investigate how the readiness to believe conspiracy theories and the three dimensions of health locus of control (HLOC) affect the attitude toward vaccination. A cross-sectional study was conducted based on the data from an online survey of a sample of Czech university students (n = 866) collected in January 2021, using the multivariate linear regression models and moderation analysis. The results found that 60% of Czech students wanted to get vaccinated against COVID-19. In addition, 40% of the variance of willingness to get vaccinated was explained by the belief in the COVID-19-related conspiracy theories and the powerful others dimension of HLOC. One-sixth of the variance of the willingness to get vaccinated was explained by HLOC, cognitive reflection, and digital health literacy [eHealth Literacy Scale (EHEALS)]. HLOC and conspiracy mentality (CM) and its predictors are valid predictors of a hesitancy to get vaccinated against COVID-19. The campaigns promoting vaccination should target the groups specifically vulnerable to the conspiracy theories and lacking HLOC related to powerful others.

Rather than inducing psychological reactance, requiring vaccination strengthens intentions to vaccinate in US populations

In a survey and three experiments (one preregistered with a nationally representative sample), we examined if vaccination requirements are likely to backfire, as commonly feared. We investigated if relative to encouraging free choice in vaccination, requiring a vaccine weakens or strengthens vaccination intentions, both in general and among individuals with a predisposition to experience psychological reactance. In the four studies, compared to free choice, requirements strengthened vaccination intentions across racial and ethnic groups, across studies, and across levels of trait psychological reactance. The results consistently suggest that fears of a backlash against vaccine mandates may be unfounded and that requirements will promote COVID-19 vaccine uptake in the United States.

Quantifying healthcare and welfare sector workers' preferences around COVID-19 vaccination: a cross-sectional, single-profile discrete-choice experiment in France

OBJECTIVES

To analyse preferences around promotion of COVID-19 vaccination among workers in the healthcare and welfare sector in Fance at the start of the vaccination campaign.

DESIGN

Single-profile discrete-choice experiment. Respondents in three random blocks chose between accepting or rejecting eight hypothetical COVID-19 vaccination scenarios.

SETTING

4346 healthcare and welfare sector workers in France, recruited through nation-wide snowball sampling, December 2020 to January 2021.

OUTCOME

The primary outcomes were the effects of attributes' levels on hypothetical acceptance, expressed as ORs relative to the reference level. The secondary outcome was vaccine eagerness as certainty of decision, ranging from -10 to +10.

RESULTS

Among all participants, 61.1% made uniform decisions, including 17.2% always refusing vaccination across all scenarios (serial non-demanders). Among 1691 respondents making variable decisions, a strong negative impact on acceptance was observed with 50% vaccine efficacy (compared with 90% efficacy: OR 0.05, 95% CI 0.04 to 0.06) and the mention of a positive benefit-risk balance (compared with absence of severe and frequent side effects: OR 0.40, 0.34 to 0.46). The highest positive impact was the prospect of safely meeting older people and contributing to epidemic control (compared with no indirect protection: OR 4.10, 3.49 to 4.82 and 2.87, 2.34 to 3.50, respectively). Predicted acceptance was 93.8% for optimised communication on messenger RNA vaccines and 16.0% for vector-based vaccines recommended to ≥55-year-old persons. Vaccine eagerness among serial non-demanders slightly but significantly increased with the prospect of safely meeting older people and epidemic control and reduced with lower vaccine efficacy.

DISCUSSION

Vaccine promotion towards healthcare and welfare sector workers who hesitate or refuse vaccination should avoid the notion of benefit-risk balance, while collective benefit communication with personal utility can lever acceptance. Vaccines with limited efficacy will unlikely achieve high uptake.

Anticipating pride or regret? Effects of anticipated affect focused persuasive messages on intention to get vaccinated against COVID-19

Understanding the factors that increase intention to receive COVID-19 vaccines is essential to maximise the vaccination campaign effectiveness. The present experimental study evaluated the effect of exposure to messages targeting cognitive attitude plus anticipated positive (pride) or negative (regret) affective reactions on intention to get vaccinated. Participants included 484 Italian adults randomly allocated to one of four conditions: 1) cognitive attitude message; 2) cognitive attitude plus positive affect message; 3) cognitive attitude plus negative affect message; 4) control condition (no message). Results showed that participants in the second condition reported greater intention to get vaccinated against COVID-19 compared with those in the control condition. Parallel mediation analysis indicated that the effect of the second condition on intention was fully mediated by cognitive attitude and anticipated positive affect. These findings suggest that future campaigns aimed at promoting COVID-19 vaccination intention could usefully target both cognitive attitude and anticipated positive affect.

Knowledge, beliefs, attitudes and perceived risk about COVID-19 vaccine and determinants of COVID-19 vaccine acceptance in Bangladesh

Bangladesh govt. launched a nationwide vaccination drive against SARS-CoV-2 infection from early February 2021. The objectives of this study were to evaluate the acceptance of the COVID-19 vaccines and examine the factors associated with the acceptance in Bangladesh. In between January 30 to February 6, 2021, we conducted a web-based anonymous cross-sectional survey among the Bangladeshi general population. At the start of the survey, there was a detailed consent section that explained the study’s intent, the types of questions we would ask, the anonymity of the study, and the study’s voluntary nature. The survey only continued when a respondent consented, and the answers were provided by the respondents themselves. The multivariate logistic regression was used to identify the factors that influence the acceptance of the COVID-19 vaccination. A total of 605 eligible respondents took part in this survey (population size 1630046161 and required sample size 591) with an age range of 18 to 100. A large proportion of the respondents are aged less than 50 (82%) and male (62.15%). The majority of the respondents live in urban areas (60.83%). A total of 61.16% (370/605) of the respondents were willing to accept/take the COVID-19 vaccine. Among the accepted group, only 35.14% showed the willingness to take the COVID-19 vaccine immediately, while 64.86% would delay the vaccination until they are confirmed about the vaccine’s efficacy and safety or COVID-19 becomes deadlier in Bangladesh. The regression results showed age, gender, location (urban/rural), level of education, income, perceived risk of being infected with COVID-19 in the future, perceived severity of infection, having previous vaccination experience after age 18, having higher knowledge about COVID-19 and vaccination were significantly associated with the acceptance of COVID-19 vaccines. The research reported a high prevalence of COVID-19 vaccine refusal and hesitancy in Bangladesh. To diminish the vaccine hesitancy and increase the uptake, the policymakers need to design a well-researched immunization strategy to remove the vaccination barriers. To improve vaccine acceptance among people, false rumors and misconceptions about the COVID-19 vaccines must be dispelled (especially on the internet) and people must be exposed to the actual scientific facts.

To Get Vaccinated, or Not to Get Vaccinated, That Is the Question: Illness Representations about COVID-19 and Perceptions about COVID-19 Vaccination as Predictors of COVID-19 Vaccination Willingness among Young Adults in The Netherlands

Mass vaccination is considered necessary to reduce the spread of COVID-19; however, vaccination willingness was found to be especially low among young adults. Therefore, based on the extended Common Sense Model, the unique effects and the interplay of illness representations about COVID-19 and perceptions about COVID-19 vaccination in explaining COVID-19 vaccination willingness was investigated using a cross-sectional design. An online survey measuring the relevant variables was filled in by 584 participants (69.9% female) between 18 and 34 years. Correlation analyses showed that all illness representation dimensions except from timeline and both dimensions of vaccination perceptions were related to vaccination willingness. The mediation analysis revealed that less personal control, more prevention control, more concerns about COVID-19 as well as more perceived necessity of and fewer concerns about the vaccination were directly related to higher vaccination willingness. Additionally, prevention control was indirectly related to higher vaccination willingness through stronger perceptions of necessity of the vaccination. The extended Common Sense Model proved to be useful in the context of illness prevention. Campaigns to improve vaccination rates should aim at increasing the perception that COVID-19 is preventable through vaccination and the personal need of the vaccination as well as at decreasing concerns about the vaccination.

Demographic, psychological, and experiential correlates of SARS-CoV-2 vaccination intentions in a sample of Canadian families

The COVID-19 pandemic has been ongoing for close to a year, with second waves occurring presently and many viewing vaccine uptake as the most likely way to curb successive waves and promote herd immunity. Reaching herd immunity status likely necessitates that children, as well as their parents, receive a vaccine targeting SARS-CoV-2. In this exploratory study, we investigated the demographic, experiential, and psychological factors associated with the anticipated likelihood and speed of having children receive a SARS-CoV-2 vaccine in a sample of 455 Canadian families (858 children; parents' mean age = 38.2 ± 6.82 years). Using linear mixed-effects and proportional odds logistic regression models, we demonstrated that older parental age, living in the Prairies (relative to Central Canada), more complete child vaccination history, and a greater tendency to prioritise the risks of the disease relative to the risks of side effects (i.e. lower omission bias) were associated with higher likelihoods of intention to vaccinate participants' children, with trend-level associations with lower perceived danger of the vaccine and higher psychological avoidance of the pandemic. Faster speed of intended vaccination was predicted by a similar constellation of variables with an additional predictor of a child in the family having a COVID-19 related health risk being associated with slower intended speed. Results are discussed concerning public health knowledge mobilisation and the unique Canadian health landscape.

Understanding the psychosocial determinants of Italian parents' intentions not to vaccinate their children: an extended theory of planned behaviour model

OBJECTIVE

This study aimed to identify the psychosocial factors involved in Italian parents' intentions not to vaccinate their children. For this purpose, we used an extended version of the Theory of Planned Behaviour, which included both proximal and distal factors influencing intention not to vaccinate children.

DESIGN

Participants included 447 Italian parents, each completed an online questionnaire, which measured intention not to vaccinate children, attitude toward not vaccinating, subjective norms, perceived behavioural control, anticipated regret, negative attitude toward vaccines, risk perception, trust in healthcare institutions, trust in science and religious morality.

RESULTS

Results showed that attitude toward not vaccinating was strongly associated with intention not to vaccinate children. Furthermore, attitude toward not vaccinating was associated with negative attitude toward vaccines, which in turn was affected by all the distal factors considered (risk perception, trust in healthcare institutions, trust in science, religious morality). Finally, negative attitude toward vaccines fully mediated the effect of the distal factors on attitude toward not vaccinating children.

CONCLUSION

These findings provide support for the validity of the proposed extended TPB model in explaining parents' intention not to vaccinate children. Theoretical and practical implications, in terms of understanding and promoting vaccination behaviour, are discussed.

COVID-19 vaccination intention in the UK: results from the COVID-19 vaccination acceptability study (CoVAccS), a nationally representative cross-sectional survey

To investigate factors associated with intention to be vaccinated against COVID-19 we conducted a cross-sectional survey of 1,500 UK adults, recruited from an existing online research panel. Data were collected between 14th and 17th July 2020. We used linear regression analyses to investigate associations between intention to be vaccinated for COVID-19 "when a vaccine becomes available to you" and sociodemographic factors, previous influenza vaccination, general vaccine attitudes and beliefs, attitudes and beliefs about COVID-19, and attitudes and beliefs about a COVID-19 vaccination. 64% of participants reported being very likely to be vaccinated against COVID-19, 27% were unsure, and 9% reported being very unlikely to be vaccinated. Personal and clinical characteristics, previous influenza vaccination, general vaccination beliefs, and beliefs and attitudes about COVID-19 and a COVID-19 vaccination explained 76% of the variance in vaccination intention. Intention to be vaccinated was associated with more positive general COVID-19 vaccination beliefs and attitudes, weaker beliefs that the vaccination would cause side effects or be unsafe, greater perceived information sufficiency to make an informed decision about COVID-19 vaccination, greater perceived risk of COVID-19 to others (but not risk to oneself), older age, and having been vaccinated for influenza last winter (2019/20). Despite uncertainty around the details of a COVID-19 vaccination, most participants reported intending to be vaccinated for COVID-19. Actual uptake may be lower. Vaccination intention reflects general vaccine beliefs and attitudes. Campaigns and messaging about a COVID-19 vaccination could consider emphasizing the risk of COVID-19 to others and necessity for everyone to be vaccinated.

Using structural equation modeling to predict Indian people's attitudes and intentions towards COVID-19 vaccination

BACKGROUND AND AIM

Understanding people's attitudes towards Covid-19 vaccination is crucial to the successful implementation of a vaccination program. Hence this research study seeks to identify critical factors influencing Indian people's attitudes and intentions to take up Covid-19 vaccinations.

METHODS

An online questionnaire was administered to a sample (n = 254) drawn from Indian population, to assess the impact of perceived benefits, risk perceptions, social media exposure, social norms, and trust associated with Covid-19 vaccines on people's attitudes towards Covid-19 vaccines and their intentions to take up the Covid-19 vaccinations.

RESULTS

The findings showed that the perceived benefits, social norms, and trust correlated significantly with people's attitudes towards Covid-19 vaccinations. In contrast, risk perceptions and social media exposure showed an insignificant influence on people's attitudes towards Covid-19 vaccinations. Social norms, trust, and people's attitudes towards the Covid-19 vaccinations are significantly correlated with their intentions to take up Covid-19 vaccinations. On the contrary, social media exposure was found to have an insignificant influence on people's intentions to take up Covid-19 vaccinations.

CONCLUSION

Participants' intentions to take up Covid-19 vaccinations was influenced mainly by their attitudes and perceptions of Covid-19 vaccines in general, which strongly confirms the importance of various dimensions (perceived benefits, trust, social norms) of Covid-19 vaccines in cultivating Covid-19 vaccination acceptance among participants'.

When politics collides with public health: COVID-19 vaccine country of origin and vaccination acceptance in Brazil

This study examines the effect of the country of origin of the vaccine on vaccination acceptance against COVID-19. More specifically, we show how the political context in Brazil has affected acceptance of vaccines produced in China, Russia, the US, and England at the University of Oxford. Our data come from a survey experiment applied to a national sample of 2771 adult Brazilians between September 23 and October 2, 2020. We find greater rejection among Brazilians for vaccines developed in China and Russia, as compared to vaccines from the US or England. We also find that rejection of the Chinese-developed vaccine is particularly strong among those who support President Jair Bolsonaro—a COVID-19 denier and strong critic of China and vaccination, in general.

Attitudes and Perception of Healthcare Workers Concerning Influenza Vaccination during the 2019/2020 Season: A Survey of Sicilian University Hospitals

Influenza is an infectious disease with a high impact on the population in terms of morbidity and mortality, but despite International and European guidelines, vaccination coverage rates among healthcare workers (HCWs) remain very low. The aim of the present study was to evaluate influenza vaccination adherence in the three Sicilian University Hospitals of Catania, Messina, and Palermo and to understand the attitudes and perceptions of vaccinated healthcare workers and the main reasons for vaccination refusal. A cross-sectional survey through a self-administered questionnaire was conducted during the 2019/2020 influenza season. Overall, 2356 vaccinated healthcare workers answered the questionnaire. The main reason reported for influenza vaccination adherence during the 2019/2020 season was to protect patients. Higher self-perceived risk of contracting influenza and a positive attitude to recommending vaccination to patients were significantly associated with influenza vaccination adherence during the last five seasons via multivariable analysis. Fear of an adverse reaction was the main reason for influenza vaccine refusal. In accordance with these findings, Public Health institutions should develop and tailor formative and informative campaigns to reduce principal barriers to the immunization process and promote influenza vaccination adherence among HCWs.

The intentions to get vaccinated against influenza and actual vaccine uptake among diabetic patients in Ningbo, China: identifying motivators and barriers

BACKGROUND

Health authorities recommend influenza vaccination to diabetic patients. Nevertheless, the vaccination coverage of adults was low in China. This study aimed to estimate influenza vaccination intentions and actual uptake among diabetic patients in China and identify the motivators and barriers associated with vaccination.

METHODS

During Nov 2016-Jan 2017, 1960 diabetic patients were invited to participate in the investigation about influenza vaccination based on health belief model (HBM). To link vaccination intention to behavior, a follow-up survey was conducted to collect vaccination records of the 2016-2017 season. Predictors of the motivation to obtain influenza vaccination were assessed using logistic regressions.

RESULTS

1914 diabetic patients completed the survey. 46.13% participants reported intentions to be vaccinated against influenza and 7.84% actually received vaccination. In the multivariate models, while all the domains of HBM constructs were associated with intentions, age, increasing numbers of comorbidity, urban residents, perceived susceptibility, perceived benefits, free vaccination, and vaccination history displayed positive associations with vaccine uptake while increasing income and perceptions of barriers were negative predictors of vaccine uptake. Besides, interactions between perceived susceptibility and healthcare workers' (HCW's) recommendation, perceived severity and benefits, perceived severity and health-seeking behaviors, perceived benefits, and influence of family/friends had a significant positive effect modification on the vaccine uptake.

CONCLUSION

To improve diabetic patients' influenza vaccination and close the intention-behavior gap, multipronged strategies are required not only to increase vaccination intention by promoting HCW's recommendation to improve perceptions about influenza vaccination but also facilitate a follow through on initial intentions by implementing free influenza vaccination program funded by the government.

Herd immunity communication counters detrimental effects of selective vaccination mandates: Experimental evidence

BACKGROUND

Low vaccine uptake results in regular outbreaks of severe diseases, such as measles. Selective mandates, e.g. making measles vaccination mandatory (as currently implemented in Germany), could offer a viable solution to the problem. However, prior research has shown that making only some vaccinations mandatory, while leaving the rest to voluntary decisions, can result in psychological reactance (anger) and decreased uptake of voluntary vaccines. Since communicating the concept of herd immunity has been shown to increase willingness to vaccinate, this study assessed whether it can buffer such reactance effects.

METHODS

A total of N = 576 participants completed a preregistered 2 (policy: selective mandate vs. voluntary decision) × 2 (communication: herd immunity explained yes vs. no) factorial online experiment (AsPredicted #26007). In a first scenario, the concept of herd immunity was either introduced or not and vaccination either mandatory or voluntary, depending on condition. The dependent variable was the intention to vaccinate in the second scenario, where vaccination was always voluntary. Additionally, we explored the mediating role of anger between policies and intentions.

FINDINGS

Herd immunity communication generally increased vaccination intentions; selective mandates had no overall effect on intentions, and there was no interaction of the factors. However, selective mandates led to increased anger when herd immunity was not explained, leading in turn to lower subsequent vaccination intentions.

INTERPRETATION

Explaining herd immunity can counter potential detrimental effects of selective mandates by preventing anger (reactance).

FUNDING

This study was funded by the University of Erfurt and the German Research Foundation (BE-3979/11-1).

An assessment of parental knowledge, attitudes, and beliefs regarding influenza vaccination

INTRODUCTION

Seasonal influenza imposes a significant clinical and economic burden. Despite the availability of an annual vaccine to prevent influenza infection and reduce disease severity, influenza vaccination rates remain suboptimal. Research suggests personal experience, perceived effectiveness, and concerns regarding vaccine safety and side effects are the most influential factors in predicting a parent's decision to vaccinate. However, current literature is primarily focused on the vaccine decision-making of healthcare workers and those at high risk for influenza complications.

METHODS

To assess parental attitudes and beliefs regarding the influenza vaccine, a brief mixed-methods survey was developed and optimized for an electronic platform. The Health Belief Model informed survey design and data analysis. Questions were classified into five core concepts: knowledge, barriers, benefits, experience, and severity. Participants were solicited from a population of parents whose children had participated in a school-based influenza surveillance study (n = 244, 73% response rate). We tested associations between responses and children's influenza vaccination status the prior season. Categorical questions were tested using Pearson's chi-squared tests and numerical or ordered questions using Mann-Whitney tests. P-values were corrected using the Bonferroni method.

RESULTS

Doubting effectiveness, concerns about side effects, inconvenience, and believing the vaccine is unnecessary were barriers negatively associated with parents' decision to vaccinate their children during the 2017-18 flu season (p < 0.001). Knowledge that the vaccine is effective in lowering risk, duration, and severity of influenza; receiving the influenza vaccine as an adult; and recognizing the importance of vaccination to prevent influenza transmission in high-risk populations were positively associated with parents' decision to vaccinate (p < 0.001).

CONCLUSION

Understanding barriers and motivators behind parents' decision to vaccinate provides valuable insight that has the potential to shape vaccine messaging, recommendations, and policy. The motivation to vaccinate to prevent influenza transmission in high-risk populations is a novel finding that warrants further investigation.

Barriers and beliefs among health-care workers regarding seasonal influenza vaccine in Al-Qassim region, Saudi Arabia

This study aimed to assess the seasonal influenza vaccine (SIV) coverage rate, and to assess knowledge, attitudes, and practice of health-care workers (HCWs) concerning the SIV. In this multicenter cross-sectional study conducted in Qassim region, Saudi Arabia, a validated questionnaire was distributed randomly among HCWs. Of 523 responses from HCWs across different institutions, 282 (53.9%) respondents were females and most respondents were aged between 30 and 39 years. Overall, 48.6% of participants had been regularly vaccinated with the SIV, and 70% were willing to be vaccinated in the coming season. Reasons for HCWs' non-adherence to the SIV included their having previously had influenza, which was not severe (20.7%), and that they were young and healthy (19.2%). Belief in the effectiveness of the SIV (72.3%) and knowledge that the SIV should be administered yearly (86.6%) was high among respondents. Less than 50% of respondents believed that vaccine safety concern is the main barrier preventing health-care institutions from providing the SIV to patients. Our study results showed suboptimal SIV coverage among HCWs in Qassim region. Educational programs and campaigns regarding the risk of influenza infection, as well as the provision of adequate information, and highlighting the importance of HCWs being vaccinated are essential. Easy access to and availability of the SIV in each region is crucial for improved vaccine coverage. Health-care institutions need to more actively encourage staff to undergo influenza vaccinations on a regular basis, especially during the influenza season.

Promoting vaccination in maternity wards ─ motivational interview technique reduces hesitancy and enhances intention to vaccinate, results from a multicentre non-controlled pre- and post-intervention RCT-nested study, Quebec, March 2014 to February 2015

BackgroundMany countries are grappling with growing numbers of parents who delay or refuse recommended vaccinations for their children. This has created a need for strategies to address vaccine hesitancy (VH) and better support parental decision-making regarding vaccination.AimTo assess vaccination intention (VI) and VH among parents who received an individual motivational-interview (MI) based intervention on infant immunisation during post-partum stay at a maternity ward between March 2014 and February 2015.MethodsThis non-controlled pre-/post-intervention study was conducted using the results from parents enrolled in the intervention arm of the PromoVaQ randomised control trial (RCT), which was conducted in four maternity wards across the Province of Quebec. Participants (n = 1,223) completed pre- and post-intervention questionnaires on VI and VH using Opel's score. Pre-/post-intervention measures were compared using McNemar's test for categorical variables and Wilcoxon signed-rank test for continuous variables.ResultsPre-intervention: overall VI was 78% and significantly differed across maternity wards (74%, 77%, 84%, 79%, p = 0.02). Post-intervention: VI rose significantly across maternity wards (89%, 85%, 95%, 93%) and the overall increase in VI was 12% (78% vs 90%, p < 0.0001). VH corroborated these observations, pre- vs post-intervention, for each maternity ward (28% vs 16%, 29% vs 21%, 27% vs 17%, 24% vs 13%). Overall, VH was curbed post-intervention by 40% (27% vs 16%; p < 0.0001).ConclusionsCompared with pre-intervention status, participants who received the MI-based intervention on immunisation displayed lower hesitancy and greater intention to vaccinate their infant at 2 months of age.

Influenza Vaccine Intention After a Medically Attended Acute Respiratory Infection

Background. Little is known about vaccine intention behavior among patients recovering from a medically attended acute respiratory infection. Methods. Adults ≥ 18 years old with an acute respiratory infection in the 2014-2015, 2015-2016, and 2016-2017 influenza seasons were tested for influenza and completed surveys. Across seasons, unvaccinated participants were grouped into those who intended to receive the influenza vaccine in the following season (vaccine intention) and those who did not (no vaccine intention). In 2016-2017, participants were asked the reasons for their vaccination behavior. Results. Of the 837 unvaccinated participants, 308 (37%) intended to be vaccinated the next season. The groups did not differ in demographic or overall health factors. In logistic regression, non-Whites, those reporting wheezing or nasal congestion, and those receiving an antiviral prescription were more likely to be in the vaccine intention group. That group was significantly more likely to cite perceived behavioral control reasons for not being vaccinated (forgot), while the no vaccine intention group was significantly (p < .001) more likely to report knowledge/attitudinal reasons (side effects). Conclusion. Because influenza vaccine is given annually, adults must make a conscious decision to receive the vaccine each year. Understanding the factors related to vaccination behavior and intent can help shape interventions to improve influenza vaccination rates. A medical visit at the time of an acute respiratory illness, especially one in which the provider suspects influenza, as evidenced by an antiviral prescription, is an ideal opportunity to recommend influenza vaccine in the next season, to prevent a similar experience.