Which factors are important in adults' uptake of a (pre)pandemic influenza vaccine?

COVID-19 vaccine hesitancy among adults in Liberia, April-May 2021

BACKGROUND

Vaccination is one of the most cost-effective public health interventions used to prevent diseases in susceptible populations. Despite the established efficacy of vaccines, there are many reasons people are hesitant about vaccination, and these reasons could be complex. This rapid survey estimated the prevalence of COVID-19 vaccine hesitancy and potentially contributing factors in Montserrado and Nimba counties in Liberia.

METHODS

A cross-sectional study was conducted among adults living in Liberia. The relationship between vaccine non-acceptance and sociodemographic characteristics was examined using chi-square statistics. The variables with a p-value less than 0.2 at the bivariate analysis were modelled in a binary logistic regression at a 5% level of significance. The adjusted odds ratio and 95% confidence interval are reported.

RESULTS

There were 877 participants in the study. Majority were 25-34 years of age (30.4%, 272/877), females (54.05%, 474/877), and Christians (85.2%, 747/877). Most of the participants were aware of the COVID-19 vaccine (75%, 656/877), single (41.4%, 363/877), self-employed (37.51%, 329/877), and live-in rural communities (56.1%, 492/877). Vaccine hesitancy was (29.1%, 255/877; 95% CI:26.2-32.2). Vaccine hesitancy was greater among adults living in urban areas (41%) compared to persons living in rural communities (59%) (aOR; 1.5, 95% CI: 1.1-2.1) and respondents aged 45-54 years (aOR:0.5; 95% CI: 0.2-0.9; p = 0.043) were 50% less likely to be hesitant to COVID-19 vaccination compared to those more than 55 years. The most common source of information was the media (53%, 492/877) and the main reason for being hesitant was a need for more information about the vaccine and its safety (84%, 215/255).

CONCLUSIONS

The majority of study participants were aware of the COVID-19 vaccines and their most common source of information was the media (television, radio). Vaccine hesitancy was moderate. This could pose a challenge to efforts to control the spread of the COVID-19 pandemic. Therefore, the health authorities should provide more health education on the importance of vaccines and their safety to the populace.

Associations between Vaccination Behavior and Trust in Information Sources Regarding COVID-19 Vaccines under Emergency Approval in Japan: A Cross-Sectional Study

We examined the association between COVID-19 vaccination behavior and trust in COVID-19-related information sources during the initial period of COVID-19 vaccination in Japan. A cross-sectional survey was conducted in August 2021, 5 months after the start of COVID-19 vaccination for the general public under emergency approval. Participants were recruited using non-probability quota sampling from among Japanese residents who were under a declared state of emergency. Sociodemographic data, vaccination behavior, and levels of trust in eight media sources of information and three interpersonal information sources were assessed using an online survey form. A total of 784 participants completed the survey. The results of multiple logistic regression analysis showed that age, household income, underlying medical conditions, and living with family were significantly associated with COVID-19 vaccination behavior. Regarding COVID-19 vaccine information sources, trust in public health experts as a source of media information and primary care physicians as a source of interpersonal information showed significantly positive associations with COVID-19 vaccination behavior (odds ratio [OR] = 1.157, 95% confidence interval [CI] 1.017-1.31; OR = 1.076; 95% CI 1.006-1.150, respectively). Increasing trust in public health experts and primary care physicians and disseminating vaccine information from these sources will help promote vaccination under emergency approval.

Association between COVID-19 vaccine hesitancy and trust in the medical profession and public health officials

One's personal physician, national and state or local public health officials, and the broader medical profession play important roles in encouraging vaccine uptake for COVID-19. However, the relationship between trust in these experts and vaccine hesitancy has been underexplored, particularly among racial/minority groups where historic medical mistrust may reduce uptake. Using an April 2021 online sample of US adults (n = 3041) that explored vaccine hesitancy, regression models estimate levels of trust in each of these types of experts and between trust in each of these experts and the odds of being COVID-19 vaccine takers vs refusers or hesitaters. Interaction terms assess how levels of trust in the medical profession by race/ethnicity are associated with vaccine hesitancy. Trust in each expert is positively associated with trust in other experts, except for trust in the medical profession. Only trust in one's own doctor was associated with trust in the medical profession, as measured by factor scores derived from a validated scale. Lower levels of trust in experts were significantly associated with being either a hesitater or a refuser compared to being a taker. Black respondents had higher odds of being either a hesitater or a refuser compared to white respondents but the interaction with trust was insignificant. For Hispanic respondents only, the odds of being a hesitater declined significantly when trust in the medical profession rose. Mistrust in the medical profession, one's doctor and national experts contributes to vaccine hesitancy. Mobilizing personal physicians to speak to their own patients may help.

Trust in Doctors, Positive Attitudes, and Vaccination Behavior: The Role of Doctor-Patient Communication in H1N1 Vaccination

Although there is a wide variety of scientific evidence that demonstrates the benefits of vaccination on a multitude of diseases, vaccination rates remain low while misperceptions about vaccines are on the rise. The primary objective of the present study is to examine the role of doctor-patient communication and vaccination. We test the impact of doctor-patient communication on trust in doctors' vaccine recommendations as a mediator, to understand the mechanisms leading to positive vaccination attitudes, and ultimately leading to actual H1N1 vaccination behavior. We use data from a nationally representative U.S. sample from one of the Multimedia Audience Research Systems (MARS) data sets collected by Kantar Media. Our results demonstrate the crucial role of doctor-patient communication in building patients' trust in doctors, which in turn positively impact vaccination attitudes and H1N1 vaccination behavior. Unlike other preventive health measures, getting vaccines after a pandemic is a critical decision because these vaccines are previously unknown. Our finding implies that verified communication from the physician's office may be one of the effective strategies during or after a pandemic. Our findings have implications for public health organizations to incorporate effective vaccination communication and could have critical implications for the COVID-19 vaccination.

Vaccination and vacci-notions: Understanding the barriers and facilitators of COVID-19 vaccine uptake during the 2020-21 COVID-19 pandemic

Objective

The COVID-19 pandemic continues to place an inordinate burden on U.S. population health, and vaccination is the most powerful tool for curbing SARS-CoV-2 transmission, saving lives, and promoting economic recovery. However, much of the U.S. population remains hesitant to get vaccinated against COVID-19, despite having access to these life-saving vaccines. This study's objective was to examine the demographic characteristics, experiences, and disease- and vaccine-related risk perceptions that influence an individual's decision to adhere to vaccine recommendations for COVID-19.

Study design

A telephone survey was performed with a convenience sample of 57 participants.

Methods

This mixed-methods study collected quantitative and qualitative responses about seasonal influenza and COVID-19 vaccine intentions to compare vaccine hesitancies between a novel and routine vaccine.

Results

The primary facilitators of uptake for the COVID-19 vaccine were personal protection, protecting others, preserving public health, and general vaccine confidence. Concerns about vaccine side effects, concerns about the COVID-19 vaccine trials, misinformation about vaccination, personal aversions to the vaccine, general distrust in vaccination, complacency, and distrust in government were the primary barriers to vaccine uptake. Race was also associated with COVID-19 vaccine intentions.

Conclusions

The results of this research have been condensed into four recommendations designed to optimize public health messaging around the COVID-19 vaccine and maximize future vaccine uptake.

The Role of General Attitudes and Perceptions Towards Vaccination on the Newly-Developed Vaccine: Results From a Survey on COVID-19 Vaccine Acceptance in China

Background

Vaccination has been considered one of the most effective public health interventions. In the context of the global epidemic of coronavirus disease 2019 (COVID-19), it remains unclear what role general vaccination attitudes and perceptions have on the acceptance of COVID-19 vaccine.

Objective

This study aims to explore the impact of general attitudes and perceptions toward vaccination on the acceptance of a newly developed vaccine, taking COVID-19 vaccines as an example.

Method

A cross-sectional survey was conducted among 2,013 Chinese adult participants. Generalized order logistic regression and path analysis models were used to analyze impacts of general attitudes and perceptions toward vaccination on the acceptance of the COVID-19 vaccine.

Results

The prevalence of hesitancy to vaccination in general is 49.9% among the Chinese adult population. General perceptions of vaccination were associated with corresponding perceptions of the COVID-19 vaccine. A “no hesitancy” attitude toward vaccination is a significant determinant (aOR = 1.77, 95% CI = 1.36–2.31) of future COVID-19 vaccination compared to vaccine refusers, and perceptions of COVID-19 vaccine remain a significant determinant for the acceptance of the COVID-19 vaccine. Path analysis indicates that perceptions of the importance and safety of vaccination have a positive overall effect on the acceptance of the COVID-19 vaccine, and that general perceptions of vaccination as a whole on each measure indirectly influence the acceptance of the COVID-19 vaccine.

Conclusion

General attitudes and perceptions toward vaccination were associated with those of the COVID-19 vaccine and future vaccination intention. To prepare for possible emergence of diseases in the future, routine health campaigns should be launched by relevant government departments and vaccination authorities to enhance the overall awareness and knowledge of vaccination among the public and to ensure optimal vaccination experience. In addition, targeted knowledge dissemination and mass mobilizations should be urged for newly developed vaccines when some specific infectious diseases emerge, such as COVID-19 at present.

Pro-vaccination Groups Expressing Hesitant Attitudes: A Cross-Sectional Study About the Difference Between Attitudes and Actual Behavior in Israel

Background

Vaccines have contributed to the decline in mortality, morbidity, and even the eradication of various infectious diseases. Over time, the availability of information to the public and the request for public involvement in the health decision-making process have risen, and the confidence in vaccines has dropped. An increasing number of parents and individuals are choosing to delay or refuse vaccines.

Objectives

(1) Identifying hesitant attitudes among pro-vaccination parents; (2) testing the difference between the rate of hesitant attitudes and the rate of hesitancy in practice among pro-vaccination parents; and (3) examining the association of sociodemographic characteristics (gender, age, marital status education and religious affiliation) with the difference between hesitant attitudes and hesitancy in practice among pro-vaccination parents.

Methods

Descriptive cross-sectional survey using an online survey that measured vaccine hesitancy among pro-vaccination parents (n = 558) whose children were in kindergarten (3–5 years), according to a variety of sociodemographic characteristics.

Results

A significant difference was found between the rate of hesitant attitudes and the rate of hesitation in actual vaccination among pro-vaccination and hesitant parents, where despite that 26% of the parents had hesitant attitudes, only 19% hesitated in practice [P = 0.0003]. There was also a significant difference between the rate of hesitant attitudes and the rate of hesitancy in practice among women [P = 0.0056] and men [P = 0.0158], parents between 30 and 39 years of age [P = 0.0008], traditional parents [P = 0.0093], Non-academic parents [P = 0.0007] and parents with BA degree [P = 0.0474].

Conclusion

Pro-vaccination individuals may have hesitant attitudes regarding vaccines. Therefore, it is very important for health authorities to address the public's fears and concerns, including those who are classified as pro-vaccination.

The psychological and behavioural correlates of COVID-19 vaccine hesitancy and resistance in Ireland and the UK

Background

The successful control of the COVID-19 pandemic depends largely on the acceptance and uptake of a COVID-19 vaccine among the public. Thus, formative research aiming to understand and determine the causes of weak and/or positive vaccination intentions is vital in order to ensure the success of future and current vaccination programmes through the provision of effective, evidence-based health messaging.

Methods

A cross-sectional survey was completed by a sample of Irish (N = 500) and UK (N = 579) citizens using the online platform ‘Qualtrics’. Participants completed a questionnaire battery comprised of health, attitudes/beliefs, influences, and behavioural intention measures. Demographic information was also assessed.

Results

Results highlighted similar rates of vaccine intention among both samples; where a total of 76.8% Irish respondents, and 73.7% of UK respondents indicated that they intended to be immunized if the government advised them to take the COVID-19 vaccine. Overall, 23.2% of Irish respondents reported being vaccine hesitant or vaccine resistant, while a rate of 26.3% of UK respondents reported vaccine hesitancy or resistance. Univariate analysis highlighted that both gender and age played a significant role in vaccine intention, with women under age 30 reporting higher rate of vaccine hesitancy. Multivariate analysis revealed that significant correlates of vaccine acceptance included peer influence, GP influence, civic responsibility, perceived benefit, and positive vaccination attitudes. Those who reported vaccine resistance and hesitancy were more likely to have less positive vaccination attitudes and perceive higher vaccination risk.

Discussion

The current sociodemographic and psychological profiles of vaccine resistant and hesitant individuals provide a useful resource for informing health practitioners in the UK and Ireland with the means of enhancing pro-vaccine attitudes and promoting vaccination uptake. The current research shows indications of associations between distrust in the vaccine itself and vaccine hesitancy and resistance. Thus, to effectively design and deliver public health messages that ensures the success of vaccination uptake, it is likely that governments and public health officials will need to take actions to garner trust in the safety of the vaccine itself. Additionally, campaigns to decrease hesitancy and resistance in the COVID-19 vaccine may benefit in targeting altruism to increase willingness to get vaccinated against COVID-19.

Trust in physicians and trust in government predict COVID-19 vaccine uptake

OBJECTIVE

We consider how trust in government, trust in physicians, and interpersonal trust affect the likelihood of COVID-19 vaccine uptake.

METHODS

A survey of 3057 registered South Dakota voters was fielded in April 2021 that measured COVID-19 vaccine uptake, three aspects of trust, and several other factors related to vaccine hesitancy. Logistic regression was utilized to analyze the responses.

RESULTS

We found positive, statistically significant, and substantively impactful effects for trust in government and trust in physicians on the likelihood of COVID-19 vaccine uptake, and null results for interpersonal trust.

CONCLUSIONS

Our findings provide a more nuanced understanding of the relationship between trust and COVID-19 vaccine uptake, and suggest that public health official as well as physicians should strive to increase the public's trust in the medical community.

Using the Health Belief Model to examine travelers' willingness to vaccinate and support for vaccination requirements prior to travel

Data from a survey of 1478 travelers and multistep group structural equation model analysis revealed that the Health Belief Model constructs of cues to action (trust in third-party information sources), perceived severity of and susceptibility to COVID-19, and beliefs about the protection benefits of a COVID-19 vaccine, subsequently elicited willingness to vaccinate and beliefs that others should vaccinate prior to travel and enhanced support for pre-travel vaccination mandates. Also, significant differences in the perceived protection benefits of the vaccine and willingness to vaccinate were found across groups of travelers who travel more or less frequently and those with and without a prior positive test for COVID-19. The study provides a theoretically informed understanding of the dynamics that may enable the success of important health-related travel policy in the wake of COVID-19 and future pandemics and identifies the communication mechanisms that must be leveraged by governments and travel authorities in enforcing policy.

Effect of a Concise Educational Program on COVID-19 Vaccination Attitudes

Background: Vaccination has been recognized as a vital step for containing the COVID-19 outbreak. To ensure the success of immunization efforts as a public health containment measure, a high level of public vaccination compliance is essential. Targeted educational programs can be utilized to improve attitudes toward vaccination and improve the public's uptake of protective measures.

Methods: In this cross-sectional study, we aimed to evaluate the impact of a concise educational program on perceived knowledge regarding the COVID-19 vaccine, vaccine importance and trust, protection and fear from COVID-19, trust in authorities, as well as individual resilience.

Results: The study evaluated 503 participants that completed the questionnaire before and after viewing a concise video tutorial on vaccination. Following the educational program, scores of five variables increased significantly compared to their pre-viewing level: knowledge, personal resilience, trust in authorities, vaccine importance, as well as perceived protection. Those that were vaccinated and/or intend to be vaccinated (N = 394) report higher levels of knowledge, trust in authorities, vaccine importance, vaccine trust, and fear of being infected as compared to those that are unwilling to get vaccinated. Positive significant correlations were found between resilience and trust in authorities (r = 0.169, p < 0.001), vaccine importance (r = 0.098, p = 0.028), and feeling protected (r = 0.310, p < 0.001). Trust in authorities was positively correlated with vaccine importance (r = 0.589, p < 0.001) and vaccine trust (r = 0.177, p < 0.001). Vaccine importance was positively correlated with vaccine trust (r = 0.149, p = 0.001), but not correlated with knowledge score.

Conclusion: The findings of the study demonstrate the benefits of educational programs on improving attitudes toward vaccination acceptability. Incorporation of such concise educational programs by authorities may improve uptake of COVID-19 vaccination and help overcome public vaccine hesitancy. We recommend that such a concise and easily implementable educational program be incorporated as a response component to the current and future outbreaks.

Public Perceptions and Acceptance of COVID-19 Booster Vaccination in China: A Cross-Sectional Study

Coronavirus disease 2019 (COVID-19) booster vaccination has been proposed in response to the new challenges of highly contagious variants, yet few studies have examined public acceptance of boosters. This study examined public acceptance of COVID-19 booster vaccination and its influencing factors by using the data from a self-administered online cross-sectional survey conducted in June 2021 in China. Multiple logistic analysis was used to examine the influencing factors of booster acceptance based on the health belief model (HBM). Among 1145 respondents, 84.80% reported to accept COVID-19 booster vaccination. Having COVID-19 vaccination history, perceiving high benefits and low barriers to booster vaccination, being younger (18-30 vs. 41-50), having a lower education level, being employed, and belonging to priority groups for vaccination were associated with increased odds of booster acceptance. The primary reason for refusing booster vaccination was concern about vaccine safety. The vast majority (92.8%) of respondents reported an annual willingness to pay between 0 and 300 CNY (0-46.29 USD) if the booster was not free. Our findings suggest that the acceptance rate of booster vaccination is relatively high in China, and the HBM-based analysis reveals that more efforts are needed to increase perceived benefits and reduce perceived barriers of vaccination to design effective and proper vaccination extension strategies when boosters become widely recommended.

Knowledge, Attitudes and Perception toward COVID-19 Vaccines among Adults in Jazan Province, Saudi Arabia

Background: Saudi Arabia is one of the countries that initiated early vaccination programs despite the global challenges concerning the availability of COVID-19 vaccines. Massive vaccination campaigns have been undertaken in the country; however, negative perception and hesitancy toward vaccines may exist which could reduce public response to vaccination. Further, studies evaluating the current perception and attitude toward COVID-19 vaccines are scarce. Thus, this study aims to assess the community attitudes and perceptions toward COVID-19 vaccines in Jazan Province, Saudi Arabia. Methods: A cross-sectional, retrospective study using an online questionnaire was conducted among the public in Jazan, the southern region of Saudi Arabia. General and demographic data were collected, and perception and attitude toward COVID-19 vaccines were evaluated. Results: Most participants in this study were female (67%) with a median age of 23 years. The majority held a bachelor’s degree, and they trusted the Saudi healthcare system. Our survey showed that 67% of the study participants had positive perceptions toward COVID-19 vaccines, a finding that is significantly associated with receiving the influenza vaccine in the past, the existence of trust on the current healthcare system and holding positive beliefs toward the effectiveness of the current COVID-19 vaccines in reducing the risk of infection, complication, and mortality. Conclusions: The proportion of the public in Jazan who believed in the COVID-19 vaccine effectiveness is not inferior from similar international reports. Thus, national awareness programs toward the effectiveness of the vaccine could be enhanced to accelerate vaccination coverage. Further, nationwide surveys are warranted to include larger populations from different communities to assess the overall perception toward COVID-19 vaccines in the whole country.

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.

Delivering routine immunisations in London during the COVID-19 pandemic: lessons for future vaccine delivery. A mixed-methods study

Background

General practices in England have continued to care for patients throughout the COVID-19 pandemic by instigating major changes to service delivery. Immunisations have continued, although the number of vaccines delivered initially dropped in April 2020.

Aim

To evaluate how COVID-19 impacted the delivery of immunisations in London and identify innovative practices to inform future delivery, including for COVID-19 vaccines.

Design & setting

A mixed-methods study of immunisation delivery in London, UK.

Method

An online survey of London general practices was undertaken in May 2020 to produce a descriptive analysis of childhood immunisation delivery and identify innovative delivery models. Semi-structured interviews were conducted between August and November 2020 to explore innovative immunisation models, which were analysed thematically.

Results

Sixty-eight per cent (n = 830) of London practices completed the survey and 97% reported having continued childhood immunisation delivery. Common delivery adaptations included spaced-out appointments, calling parents beforehand, and having only one parent attend. Forty-three practices were identified as having innovative models, such as delivering immunisations outside practice buildings or offering drive-through services. The thematic analysis of 14 semi-structured interviews found that, alongside adaptations to immunisation delivery within practices, existing local networks collaborated to establish new immunisation delivery models. Local population characteristics affected delivery and provide insights for large-scale vaccine deployment.

Conclusion

Immunisations continued during 2020 with practices adapting existing services. New delivery models were developed by building on existing local knowledge, experiences, and networks. Immunisation delivery during the pandemic, including for COVID-19 vaccines, should be tailored to local population needs by building on primary care immunisation expertise.

A Comparison of Vaccine Hesitancy of COVID-19 Vaccination in China and the United States

OBJECTIVES

To investigate the differences in vaccine hesitancy and preference of the currently available COVID-19 vaccines between two countries, namely, China and the United States (U.S.).

METHOD

A cross-national survey was conducted in both China and the United States, and discrete choice experiments, as well as Likert scales, were utilized to assess vaccine preference and the underlying factors contributing to vaccination acceptance. Propensity score matching (PSM) was performed to enable a direct comparison between the two countries.

RESULTS

A total of 9077 (5375 and 3702 from China and the United States, respectively) respondents completed the survey. After propensity score matching, over 82.0% of respondents from China positively accepted the COVID-19 vaccination, while 72.2% of respondents from the United States positively accepted it. Specifically, only 31.9% of Chinese respondents were recommended by a doctor to have COVID-19 vaccination, while more than half of the U.S. respondents were recommended by a doctor (50.2%), local health board (59.4%), or friends and families (64.8%). The discrete choice experiments revealed that respondents from the United States attached the greatest importance to the efficacy of COVID-19 vaccines (44.41%), followed by the cost of vaccination (29.57%), whereas those from China held a different viewpoint, that the cost of vaccination covered the largest proportion in their trade-off (30.66%), and efficacy ranked as the second most important attribute (26.34%). Additionally, respondents from China tended to be much more concerned about the adverse effect of vaccination (19.68% vs. 6.12%) and have a lower perceived severity of being infected with COVID-19.

CONCLUSION

Although the overall acceptance and hesitancy of COVID-19 vaccination in both countries are high, underpinned distinctions between these countries were observed. Owing to the differences in COVID-19 incidence rates, cultural backgrounds, and the availability of specific COVID-19 vaccines in the two countries, vaccine rollout strategies should be nation-dependent.

It runs in the family - Influenza vaccination and spillover effects

We study a population-based influenza vaccination program in the Netherlands, and the spillovers it has within families. Individuals aged 65 years and over qualify for the program and receive a personal invitation for a free flu shot, while ineligible individuals have to pay out-of-pocket and face additional barriers to getting vaccinated. The quasi-random variation at age 65 is exploited to analyse program impact on vaccination behavior of cohabiting partners and adult children. We find that the program induced a 10 percentage points increase in vaccination coverage among individuals at age 65. The program further led to a similar effect on vaccination take-up by cohabiting younger partners, but spillovers on children were negative. These asymmetric patterns of vaccination uptake are consistent with partners and children learning about influenza mortality risk, target group membership, and cost and benefits of vaccination, as well as salience. We conclude that public health campaigns should pay attention to the effects on voluntary preventive care participation as within-family spillovers impact the program's overall public health impact.

Acceptance of COVID-19 Vaccination during the COVID-19 Pandemic in China

Background: Faced with the coronavirus disease 2019 (COVID-19) pandemic, the development of COVID-19 vaccines has been progressing at an unprecedented rate. This study aimed to evaluate the acceptance of COVID-19 vaccination in China and give suggestions for vaccination strategies and immunization programs accordingly. Methods: In March 2020, an anonymous cross-sectional survey was conducted online among Chinese adults. The questionnaire collected socio-demographic characteristics, risk perception, the impact of COVID-19, attitudes, acceptance and attribute preferences of vaccines against COVID-19 during the pandemic. Multivariate logistic regression was performed to identify the influencing factors of vaccination acceptance. Results: Of the 2058 participants surveyed, 1879 (91.3%) stated that they would accept COVID-19 vaccination after the vaccine becomes available, among whom 980 (52.2%) wanted to get vaccinated as soon as possible, while others (47.8%) would delay the vaccination until the vaccine’s safety was confirmed. Participants preferred a routine immunization schedule (49.4%) to emergency vaccination (9.0%) or either of them (41.6%). Logistic regression showed that being male, being married, perceiving a high risk of infection, being vaccinated against influenza in the past season, believing in the efficacy of COVID-19 vaccination or valuing doctor’s recommendations could increase the probability of accepting COVID-19 vaccination as soon as possible, while having confirmed or suspected cases in local areas, valuing vaccination convenience or vaccine price in decision-making could hinder participants from immediate vaccination. Conclusion: During the pandemic period, a strong demand for and high acceptance of COVID-19 vaccination has been shown among the Chinese population, while concerns about vaccine safety may hinder the promotion of vaccine uptake. To expand vaccination coverage, immunization programs should be designed to remove barriers in terms of vaccine price and vaccination convenience, and health education and communication from authoritative sources are important ways to alleviate public concerns about vaccine safety.

Media representation of vaccine side effects and its impact on utilization of vaccination services in Vietnam

BACKGROUND

Media representation of vaccine side effects impacts the success of immunization programs globally. Exposure to the media can cause individuals to feel hesitant toward, or even refuse, vaccines. This study aimed to explore the impact of the media on beliefs and behaviors regarding vaccines and vaccine side effects in an urban clinic in Vietnam.

METHODS

A cross-sectional study was conducted in an urban vaccination clinic in Hanoi, Vietnam from November 2015 to March 2016. The primary outcomes of this study were the decisions of Vietnamese subjects after hearing about adverse effects of immunizations (AEFIs) in the media. Socio-demographic characteristics as well as beliefs regarding vaccination were also investigated. Multivariate logistic regression was used to identify factors associated with subjects' behaviors regarding vaccines.

RESULTS

Among 429 subjects, 68.2% of them said they would be hesitant about receiving vaccines after hearing about AEFIs, while 12.4% of subjects said they would refuse vaccines altogether after hearing about AEFIs. Wealthy individuals (OR=0.41; 95% CI=0.19-0.88), and those who displayed trust in government-distributed vaccines (OR=0.20; 95% CI=0.06-0.72) were less likely to display hesitancy regarding vaccination. Receiving information from community health workers (OR=0.44; 95% CI=0.20-0.99) and their relatives, colleagues, and friends (OR=0.47; 95% CI=0.25-0.88) was negatively associated with vaccine hesitancy, but facilitated vaccine refusal after reading about AEFIs in the media (OR=3.12; 95% CI=1.10-8.90 and OR=3.75; 95% CI=1.56-9.02, respectively).

CONCLUSION

Our results reveal a significantly high rate of vaccine hesitancy and refusal among subjects living in an urban setting in Vietnam, after hearing about AEFIs in the media. Vietnam needs to develop accurate information systems in the media about immunizations, to foster increased trust between individuals, health care professionals, and the Vietnamese government.

The benefit of the doubt or doubts over benefits? A systematic literature review of perceived risks of vaccines in European populations

OBJECTIVES

The success of vaccination strategies depends in part on population perceptions of benefits and risks of vaccines and related confidence in vaccination. Better knowledge of public concerns about vaccines and what is driving them is needed to inform vaccination strategies and communications. This literature reviewer examined studies on vaccine and vaccination risk perceptions and concerns across European populations.

METHODS

A systematic literature review was conducted to identify studies published between 2004 and 2014 in Europe. A descriptive analysis was performed.

FINDINGS

A total of 145 articles were selected, most of which were conducted in the UK, the Netherlands and France and studied seasonal influenza, HPV and pandemic influenza vaccination. Across all countries and vaccines, the primary area of concern was vaccine safety, followed by perceptions of low likelihood of contracting vaccine-preventable diseases (VPDs), perceived low severity of VPDs, beliefs that vaccines do not work, and overall lack of information. Concerns were found to be vaccine-, country- and population-specific.

CONCLUSION

In addition to identifying concerns about vaccination in Europe, this study confirmed the notion that individuals have many safety concerns about vaccination and often believe that the risks of vaccination outweigh their benefits. More research needs to be conducted to explore the impact of different types of communication strategies, which would frame the benefits of vaccination as well as risks of not vaccinating. Strategies to better inform public perceptions of vaccines should include the provision of unbiased, comprehensive information tailored to population information needs, and delivered using multiple and new communication technologies such as social media.

“Beauty contest” indicator of cognitive ability and free riding strategies. Results from a scenario experiment about pandemic flu immunization

High immunization coverage rates are desirable in order to reduce total morbidity and mortality rates, but it may also provide an incentive for herd immunity free riding strategies. The aim of this paper was to investigate the link between cognitive ability and vaccination intention in a hypothetical scenario experiment about Avian Flu immunization. A between-subject scenario experiment was utilized to examine the willingness to undergo vaccination when the vaccination coverage was proclaimed to be 36, 62 and 88%. Respondents were later assigned to a “Beauty contest” experiment, an experimental game commonly used to investigate individual's cognitive ability. Results show that there was a significant negative effect of the proclaimed vaccination uptake among others on the vaccination intention. However, there were no significant association between the “Beauty contest” indicator of cognitive ability and the use of herd immunity free riding strategies.

Public preferences for vaccination programmes during pandemics caused by pathogens transmitted through respiratory droplets - a discrete choice experiment in four European countries, 2013

This study aims to quantify and compare preferences of citizens from different European countries for vaccination programme characteristics during pandemics, caused by pathogens which are transmitted through respiratory droplets. Internet panel members, nationally representative based on age, sex, educational level and region, of four European Union Member States (Netherlands, Poland, Spain, and Sweden, n = 2,068) completed an online discrete choice experiment. These countries, from different geographical areas of Europe, were chosen because of the availability of high-quality Internet panels and because of the cooperation between members of the project entitled Effective Communication in Outbreak Management: development of an evidence-based tool for Europe (ECOM). Data were analysed using panel latent class regression models. In the case of a severe pandemic scenario, vaccine effectiveness was the most important characteristic determining vaccination preference in all countries, followed by the body that advises on vaccination. In Sweden, the advice of family and/or friends and the advice of physicians strongly affected vaccine preferences, in contrast to Poland and Spain, where the advice of (international) health authorities was more decisive. Irrespective of pandemic scenario or vaccination programme characteristics, the predicted vaccination uptakes were lowest in Sweden, and highest in Poland. To increase vaccination uptake during future pandemics, the responsible authorities should align with other important stakeholders in the country and communicate in a coordinated manner.

Contextual generalized trust and immunization against the 2009 A(H1N1) pandemic in the American states: A multilevel approach

The aim of the study was to investigate the association between contextual generalized trust and individual-level 2009 A(H1N1) pandemic immunization acceptance. A second aim was to investigate whether knowledge about the A(H1N1) pandemic mediated the association between contextual generalized trust and A(H1N1) immunization acceptance. Data from the National 2009 H1N1 Flu Survey was used. To capture contextual generalized trust, data comes from an aggregation of surveys measuring generalized trust in the American states. To investigate the association between contextual generalized trust and immunization acceptance, while taking potential individual-level confounders into account, multilevel logistic regression was used. The investigation showed contextual generalized trust to be significantly associated with immunization acceptance. However, controlling for knowledge about the A(H1N1) pandemic did not substantially affect the association between contextual generalized trust and immunization acceptance. In conclusion, contextual state-level generalized trust was associated with A(H1N1) immunization, but knowledge about A(H1N1) was not mediating this association.

A Meta-Analysis of the Association between Gender and Protective Behaviors in Response to Respiratory Epidemics and Pandemics

Respiratory infectious disease epidemics and pandemics are recurring events that levy a high cost on individuals and society. The health-protective behavioral response of the public plays an important role in limiting respiratory infectious disease spread. Health-protective behaviors take several forms. Behaviors can be categorized as pharmaceutical (e.g., vaccination uptake, antiviral use) or non-pharmaceutical (e.g., hand washing, face mask use, avoidance of public transport). Due to the limitations of pharmaceutical interventions during respiratory epidemics and pandemics, public health campaigns aimed at limiting disease spread often emphasize both non-pharmaceutical and pharmaceutical behavioral interventions. Understanding the determinants of the public’s behavioral response is crucial for devising public health campaigns, providing information to parametrize mathematical models, and ultimately limiting disease spread. While other reviews have qualitatively analyzed the body of work on demographic determinants of health-protective behavior, this meta-analysis quantitatively combines the results from 85 publications to determine the global relationship between gender and health-protective behavioral response. The results show that women in the general population are about 50% more likely than men to adopt/practice non-pharmaceutical behaviors. Conversely, men in the general population are marginally (about 12%) more likely than women to adopt/practice pharmaceutical behaviors. It is possible that factors other than pharmaceutical/non-pharmaceutical status not included in this analysis act as moderators of this relationship. These results suggest an inherent difference in how men and women respond to epidemic and pandemic respiratory infectious diseases. This information can be used to target specific groups when developing non-pharmaceutical public health campaigns and to parameterize epidemic models incorporating demographic information.

H1N1 Influenza Pandemic in Italy Revisited: Has the Willingness to Get Vaccinated Suffered in the Long Run?

Background

The aim of the study is to assess the long-term secondary effects of personal experience with the H1N1 pandemic of 2009/2010 and the perception of the institutional reaction to it on Italians’ willingness to get vaccinated in case of a novel influenza pandemic.

Design and Methods

We conducted 140 face-to-face interviews in the Registry Office of the Municipality of Milan, Italy, from October to December 2012.

Results

Willingness to get vaccinated during a novel influenza pandemic was best predicted by having been vaccinated against the seasonal flu in the past (OR=5.18; 95%CI: 1.40 to 19.13) and fear of losing one’s life in case of an infection with H1N1 (OR=4.09; 95%CI: 1.68 to 9.97). It was unaffected by the assessment of institutional performance.

Conclusions

The findings of this study do not point to long-term secondary effects of the institutional handling of the H1N1 pandemic. The results highlight the fact that behavioural intention is not the same as behaviour, and that the former cannot simply be taken as an indicator of the latter.

A belief-based model for characterizing the spread of awareness and its impacts on individuals' vaccination decisions

During an epidemic, individuals' decisions on whether or not to take vaccine may affect the dynamics of disease spread and, therefore, the effectiveness of disease control. Empirical studies have shown that such decisions can be subjected to individuals' awareness about disease and vaccine, such as their perceived disease severity and vaccine safety. The aim of this paper is to gain a better understanding of individuals' vaccination behaviour by modelling the spread of awareness in a group of socially connected individuals and examining the associated impacts on their vaccination decision-making. In our model, we examine whether or not individuals will get vaccinated as well as when they would. In doing so, we consider three possible decisions from an individual, i.e., to accept, to reject, and yet to decide, and further associate them with a set of belief values. Next, we extend the Dempster-Shafer theory to characterize individuals' belief value updates and their decision-making, having incorporated the awareness obtained from their connected neighbours. Furthermore, we examine two factors that will affect individuals' vaccination decisions: (i) reporting rates of disease- and vaccine-related events, and (ii) fading coefficient of awareness spread. By doing so, we can assess the impacts of awareness spread by evaluating the vaccination dynamics in terms of the number of vaccinated individuals. The results have demonstrated that the former influences the ratio of vaccinated individuals, whereas the latter affects the time when individuals decide to take vaccine.

Attitudes to vaccination: a critical review

This paper provides a consolidated overview of public and healthcare professionals' attitudes towards vaccination in Europe by bringing together for the first time evidence across various vaccines, countries and populations. The paper relies on an extensive review of empirical literature published in English after 2009, as well as an analysis of unpublished market research data from member companies of Vaccines Europe. Our synthesis suggests that hesitant attitudes to vaccination are prevalent and may be increasing since the influenza pandemic of 2009. We define hesitancy as an expression of concern or doubt about the value or safety of vaccination. This means that hesitant attitudes are not confined only to those who refuse vaccination or those who encourage others to refuse vaccination. For many people, vaccination attitudes are shaped not just by healthcare professionals but also by an array of other information sources, including online and social media sources. We find that healthcare professionals report increasing challenges to building a trustful relationship with patients, through which they might otherwise allay concerns and reassure hesitant patients. We also find a range of reasons for vaccination attitudes, only some of which can be characterised as being related to lack of awareness or misinformation. Reasons that relate to issues of mistrust are cited more commonly in the literature than reasons that relate to information deficit. The importance of trust in the institutions involved with vaccination is discussed in terms of implications for researchers and policy-makers; we suggest that rebuilding this trust is a multi-stakeholder problem requiring a co-ordinated strategy.

Perceptions and sociodemographic factors influencing vaccination uptake and precautionary behaviours in response to the A/H1N1 influenza in Sweden

AIMS

In response to the 2009 outbreak of A/H1N1 influenza, Swedish authorities decided on a programme for universal vaccination. Over 60% of the population received at least one dose of vaccine. This study examines demographic factors and perceptions related to the decision whether or not to become vaccinated.

METHODS

A combined web/postal survey was conducted (n = 1587, response rate 53%) in late spring 2010. Questions reported here concerned perceptions, precautionary behaviours and vaccination decision.

RESULTS

Main reasons for becoming vaccinated were concerns about spreading the disease to relatives or in the community and confidence in the good effect of vaccination. Vaccination rates were higher among women, those with young children or belonging to a risk group. Main reasons for abstaining were belief that the flu was not a serious threat, low risk of spreading the disease, concern about side-effects and perceived uncertainties in information. Three profiles representing different patterns of thought and beliefs were identified by cluster analysis, respectively labelled as a vulnerable, a trusting and a sceptical group. Vaccination rates and precautionary behaviours were demonstrated to differ between these groups.

CONCLUSIONS

Perceptions relating to the 2009 pandemic are likely to influence uptake of vaccination in the future. Authorities need to be aware of different patterns of beliefs and attitudes among the public, and that these may vary in different phases. Communication of risk needs to be dynamic and prepared to engage with the public before, during and even for some time after the acute risk period.

A computational approach to characterizing the impact of social influence on individuals' vaccination decision making

In modeling individuals vaccination decision making, existing studies have typically used the payoff-based (e.g., game-theoretical) approaches that evaluate the risks and benefits of vaccination. In reality, whether an individual takes vaccine or not is also influenced by the decisions of others, i.e., due to the impact of social influence. In this regard, we present a dual-perspective view on individuals decision making that incorporates both the cost analysis of vaccination and the impact of social influence. In doing so, we consider a group of individuals making their vaccination decisions by both minimizing the associated costs and evaluating the decisions of others. We apply social impact theory (SIT) to characterize the impact of social influence with respect to individuals interaction relationships. By doing so, we propose a novel modeling framework that integrates an extended SIT-based characterization of social influence with a game-theoretical analysis of cost minimization. We consider the scenario of voluntary vaccination against an influenza-like disease through a series of simulations. We investigate the steady state of individuals' decision making, and thus, assess the impact of social influence by evaluating the coverage of vaccination for infectious diseases control. Our simulation results suggest that individuals high conformity to social influence will increase the vaccination coverage if the cost of vaccination is low, and conversely, will decrease it if the cost is high. Interestingly, if individuals are social followers, the resulting vaccination coverage would converge to a certain level, depending on individuals' initial level of vaccination willingness rather than the associated costs. We conclude that social influence will have an impact on the control of an infectious disease as they can affect the vaccination coverage. In this respect, our work can provide a means for modeling the impact of social influence as well as for estimating the effectiveness of a voluntary vaccination program.

Vulnerable groups within a vulnerable population: awareness of the A(H1N1)pdm09 pandemic and willingness to be vaccinated among pregnant women in Ivory Coast

BACKGROUND

Because little is known about attitudes toward influenza and influenza vaccine among pregnant women in West Africa, before local distribution of A(H1N1)pdm09 vaccine in Ivory Coast we assessed knowledge of the pandemic and acceptance of the A(H1N1)pdm09 vaccine in a diverse population of pregnant women.

METHODS

A cross-sectional intercept survey of 411 pregnant women in 4 prenatal care settings was conducted during 15-28 February 2010 in Abidjan, Ivory Coast.

RESULTS

The majority (64.5%) of pregnant women said they had heard of the influenza pandemic, and of these, the majority (61.3%) were aware of the A(H1N1)pdm09 vaccine. However, awareness varied significantly by clinical setting, education level, and access to media (P < .001 for all comparisons). After adjustment for other sociodemographic factors, college-educated women were 16.8 (95% confidence interval [CI], 3.3-85.2) times as likely as women without formal education to be aware of the pandemic. After controlling for both education and demographic characteristics, women with televisions were 5 times as likely as women without television to be aware of the pandemic (adjusted odds ratio [aOR], 4.94; 95% CI, 1.34-18.17). Of those aware of the influenza pandemic, 69.8% said they would accept the A(H1N1)pdm09 vaccine while they were pregnant. Although awareness was highest in private prenatal care clinics, compared with public outpatient clinics (90.6% vs 37.5%), acceptance of vaccine was significantly lower in private settings, compared with public outpatient settings (57.3% vs 87.2%; P < .001 for each comparison).

CONCLUSIONS

Gaps in knowledge about the influenza pandemic and vaccine highlight the challenges of pandemic preparedness in poorer countries, where substantial disparities in education and media access are evident.

Novel virus, atypical risk group: understanding young adults in college as an under-protected population during H1N1 2009

Objective: To examine illness/vaccination perceptions of and intentions to vaccinate for seasonal influenza (SI) and 2009 H1N1 in the college setting. Participants: 1190 adults [M=23.5 years (SD=9.5)] from a university in the North-Eastern U.S. Methods: We deployed a web-based survey via campus email just prior to the 2009 H1N1 vaccine release. Results: Younger adults (18-24 years) had lesser understanding of the difference between influenza types, and they reported less regular and current SI vaccination compared to older adults (25-64 years). Younger respondents perceived lesser likelihood of illness from, but attributed greater severity to H1N1 versus SI. Regularity of SI vaccination and perceived vaccine efficacy were the strongest predictors of intent to vaccinate against H1N1, followed by perceived likelihood of illness and confidence in what experts know about vaccine safety. Conclusions: Young adults in college may require additional information during novel influenza pandemics. Measuring perceptions and past vaccination behaviors may facilitate targeting of preventive efforts in the college setting.

Factors Affecting Acceptance and Intention to Receive Pandemic Influenza A H1N1 Vaccine among Primary School Children: A Cross-Sectional Study in Birmingham, UK

UK pandemic influenza strategy focused on vaccination of high risk groups, although evidence shows that school-age children have the highest infection rates. Vaccination of children might be an additional strategy. We undertook a cross-sectional study amongst 149 parents of primary school children aged 4–7 years in Birmingham, UK to quantify intention to accept pandemic influenza vaccine and identify factors affecting uptake. Ninety-one (61.1%, 95% CI 52.8, 68.9) had or would accept vaccine for their child. The most common reasons for declining vaccine were concerns about safety (58.6% reported this), side effects (55.2%), or believing their child had already had swine flu (12.1%). Parents of nonwhite ethnicity (OR 2.4 (1.1, 5.0)) and with asthmatic children (OR 6.6 (1.4, 32.1)) were significantly more likely to accept pandemic vaccine, as were those whose children had ever received seasonal vaccine and those who believed swine flu to be a serious threat (OR 4.2 (1.9, 9.1)). Parents would be more likely to accept vaccination if they received a letter of invite, if the government strongly encouraged them, if it were administered at school, and if it were more thoroughly tested. Accurate media portrayal of safety of the vaccine during future pandemics will be essential.

Immunization against A/H1N1 pandemic flu (2009-2010) in pediatric patients at risk. What might be the most effective strategy? The experience of an health district of Northern Italy

Background

Vaccination coverage rates against pandemic flu were far below those required by Italian Public Health Authorities.

The aim of this retrospective study was to assess how the management of vaccination against pandemic flu in the Health District of Piacenza (Northern Italy) had conditioned the adherence of patients at risk to the H1N1flu immunization program.

Methods

From a population of 27.018 children aged between 6 months and 16 years, 2361 pediatric patients considered at risk according to the guidelines of the Ministry of Health were enrolled to receive pandemic flu vaccination.

Children enrolled in the immunization program were vaccinated with one of the following three options:

A) by their pediatrician in his office after contacting him directly or by phone

B) by their pediatrician in his office or in a public Health District office with the assistance of a nurse after an appointment had been booked by patient’s parents using a dedicated free of charge phone number

C) by a doctor of the public Health District after an appointment had been booked as for option B

Results

The best outcomes of population vaccination coverage for pandemic flu were achieved when patients were vaccinated with option B (44.2%). For options A and C rates coverage results were 22.8% (OR 2,69) and 24.9% (OR 2, 39) respectively.

Conclusion

The results of this study may be taken into account by the public health Authorities when planning the management of future immunization campaigns out of the usual vaccination schedule or in an emergency event.

Predicting intention to uptake H1N1 influenza vaccine in a university sample

OBJECTIVE

Global pandemic H1N1 was atypical of influenza in that it was associated with high symptom severity among young adults. Higher education institutions were therefore understandably concerned about the potential for high infection rates among students. This study examined intention to uptake H1N1 vaccine between November and December 2009, when the virus was classified by the World Health Organization (WHO) as being in the pandemic phase.

DESIGN

A cross-sectional survey design was employed.

METHOD

Two hundred university students completed a questionnaire battery comprised of health, belief/attitudes, and behavioural intention measures.

RESULTS

Findings suggested that non-intention to vaccinate is associated with a strong disbelief in its efficacy, in negative attitudes towards vaccinations, and in lack of perceived threat, which is underscored by a disinterest in others' opinions, including authoritative bodies. Findings also suggested that there is resistance to the idea of vaccinations being mandatory.

CONCLUSIONS

Vaccination intent is in some way linked to a range of attitudes and beliefs. The implication for health practitioners is that behaviour intent may be open to influence where psycho-education can create pro-vaccine attitudes and beliefs.

Acceptance of a pandemic influenza vaccine: a systematic review of surveys of the general public

INTRODUCTION

The effectiveness of pandemic vaccine campaigns such as the H1N1 vaccine rollout is dependent on both the vaccines' effectiveness and the general public's willingness to be vaccinated. It is therefore critical to understand the factors that influence the decision of members of the public whether to get vaccinated with new, emergently released vaccines.

METHODS

A systematic review of English language quantitative surveys was conducted to identify consistent predictors of the decision to accept or decline any (pre)pandemic vaccine, including the H1N1 influenza A vaccine. A total of ten studies were included in this review and all pertained to the 2009 H1N1 influenza A pandemic. Respondents' willingness to receive a pandemic vaccine ranged from 8%-67% across the ten studies. The factors reported to be consistent predictors of the intention to vaccinate were: risk of infection, proximity or severity of the public health event, severity of personal consequences resulting from the illness, harm or adverse events from the vaccine, acceptance of previous vaccination, and ethnicity. Age and sex were the demographic variables examined most frequently across the ten studies and there was no consistent association between these variables and the intention to accept or reject a pandemic vaccine.

CONCLUSION

Some predictors of the intention to accept or decline a (pre)pandemic vaccine or the H1N1 influenza A vaccine are consistently identified by surveys. Understanding the important factors influencing the acceptance of a pandemic vaccine by individual members of the public may help inform strategies to improve vaccine uptake during future pandemics.

Parental knowledge, attitudes and behaviours towards influenza A/H1N1 in Italy

BACKGROUND

This study assesses the level of knowledge, the attitudes and the behaviours relating to influenza A/H1N1 among parents in Italy.

METHODS

A random sample of 1299 parents aged 26-65 years received a self-reported questionnaire including questions about socio-demographic characteristics, knowledge on modes of transmission and preventative measures, attitudes and behaviours relating to influenza A/H1N1.

RESULTS

A total of 781 subjects participated with a response rate of 60.1%. Only 32.3% of the respondents correctly identified the main modes of transmission and the main preventative measures, and the results of the multivariate logistic regression analysis showed that this knowledge was significantly higher in those with a higher level of education and working as health-care personnel. The average level of perceived risk of contracting influenza A/H1N1 was 4.6 and the multivariate linear regression model showed that a greater perceived risk was significantly associated with being unmarried, having more than one son, not working in the health-care setting and needing additional information about influenza A/H1N1. Less than one-third (28.8%) of the respondents had visited a physician at least once in 2 months preceding the survey for any reason related to the influenza A/H1N1 and the multivariate logistic regression model indicated that females and those with more than one son were more likely to have a visit.

CONCLUSION

Knowledge about influenza A/H1N1 is poor and the results could have significant implications for information provision and the targeting of future education programmes to this population.

Predictors of the uptake of A (H1N1) influenza vaccine: findings from a population-based longitudinal study in Tokyo

Background

Overall pandemic A (H1N1) influenza vaccination rates remain low across all nations, including Japan. To increase the rates, it is important to understand the motives and barriers for the acceptance of the vaccine. We conducted this study to determine potential predictors of the uptake of A (H1N1) influenza vaccine in a cohort of Japanese general population.

Methodology/Principal Findings

By using self-administered questionnaires, this population-based longitudinal study was conducted from October 2009 to April 2010 among 428 adults aged 18–65 years randomly selected from each household residing in four wards and one city in Tokyo. Multiple logistic regression analyses were performed. Of total, 38.1% of participants received seasonal influenza vaccine during the preceding season, 57.0% had willingness to accept A (H1N1) influenza vaccine at baseline, and 12.1% had received A (H1N1) influenza vaccine by the time of follow-up. After adjustment for potential confounding variables, people who had been vaccinated were significantly more likely to be living with an underlying disease (p = 0.001), to perceive high susceptibility to influenza (p = 0.03), to have willingness to pay even if the vaccine costs ≥ US$44 (p = 0.04), to have received seasonal influenza vaccine during the preceding season (p<0.001), and to have willingness to accept A (H1N1) influenza vaccine at baseline (p<0.001) compared to those who had not been vaccinated.

Conclusions/Significance

While studies have reported high rates of willingness to receive A (H1N1) influenza vaccine, these rates may not transpire in the actual practices. The uptake of the vaccine may be determined by several potential factors such as perceived susceptibility to influenza and sensitivity to vaccination cost in general population.

Factors affecting intention to receive and self-reported receipt of 2009 pandemic (H1N1) vaccine in Hong Kong: a longitudinal study

Background

Vaccination was a core component for mitigating the 2009 influenza pandemic (pH1N1). However, a vaccination program's efficacy largely depends on population compliance. We examined general population decision-making for pH1N1 vaccination using a modified Theory of Planned Behaviour (TBP).

Methodology

We conducted a longitudinal study, collecting data before and after the introduction of pH1N1 vaccine in Hong Kong. Structural equation modeling (SEM) tested if a modified TPB had explanatory utility for vaccine uptake among adults.

Principal Findings

Among 896 subjects who completed both the baseline and the follow-up surveys, 7% (67/896) reported being “likely/very likely/certain” to be vaccinated (intent) but two months later only 0.8% (7/896) reported having received pH1N1 vaccination. Perception of low risk from pH1N1 (60%) and concerns regarding adverse effects of the vaccine (37%) were primary justifications for avoiding pH1N1 vaccination. Greater perceived vaccine benefits (β = 0.15), less concerns regarding vaccine side-effects (β = −0.20), greater adherence to social norms of vaccination (β = 0.39), anticipated higher regret if not vaccinated (β = 0.47), perceived higher self-efficacy for vaccination (β = 0.12) and history of seasonal influenza vaccination (β = 0.12) were associated with higher intention to receive the pH1N1 vaccine, which in turn predicted self-reported vaccination uptake (β = 0.30). Social norm (β = 0.70), anticipated regret (β = 0.19) and vaccination intention (β = 0.31) were positively associated with, and accounted for 70% of variance in vaccination planning, which, in turn subsequently predicted self-reported vaccination uptake (β = 0.36) accounting for 36% of variance in reported vaccination behaviour.

Conclusions/Significance

Perceived low risk from pH1N1 and perceived high risk from pH1N1 vaccine inhibited pH1N1 vaccine uptake. Both the TPB and the additional components contributed to intended vaccination uptake but social norms and anticipated regret predominantly associated with vaccination intention and planning. Vaccination planning is a more significant proximal determinant of uptake of pH1N1 vaccine than is intention. Intention alone is an unreliable predictor of future vaccine uptake.

A(H1N1) pandemic influenza and its prevention by vaccination: paediatricians' opinions before and after the beginning of the vaccination campaign

BACKGROUND

In June 2009, the World Health Organization declared an A(H1N1) influenza pandemic. In October 2009, the largest vaccination campaign in Canadian history began. The aim of this study was to document paediatricians' knowledge, attitudes and practices (KAP) regarding A(H1N1) pandemic influenza and its prevention by vaccination just after the beginning of the A(H1N1) vaccination campaign and to compare the results with those obtained before campaign initiation.

METHODS

A self-administered mail-based questionnaire was sent to all Canadian paediatricians. Questionnaires were analyzed in two subsets: those received before and after the beginning of the vaccination campaign.

RESULTS

Overall the response rate was 50%. Respondents' characteristics were comparable between the two subsets. Before the beginning of the campaign, 63% of paediatricians perceived A(H1N1) pandemic infection as a serious disease, that would occur frequently without vaccination compared to more than 75% after. Before the vaccination campaign, half of respondents or less thought that the A(H1N1) vaccine was safe (50%) and effective (35%) compared to 77% and 72% after. The proportion of paediatricians who reported they had received sufficient information on A(H1N1) vaccine increased from 31% before to 73% after the beginning of the vaccination campaign. The majority of respondents intended to get vaccinated against A(H1N1) influenza themselves (84% before and 92% after). Respondents' intention to recommend the A(H1N1) vaccine to their patients increased from 80% before the beginning of the campaign to 92% after. In multivariate analysis, the main determinants of paediatricians' intention to recommend the A(H1N1) vaccine were their intention to get vaccinated against A(H1N1) influenza themselves and a belief that A(H1N1) vaccine would be well accepted by health professionals who administer vaccines to the public.

CONCLUSION

Results of this study show important increases in physicians' level of confidence about A(H1N1) vaccine's safety and immunogenicity and their willingness to recommend this vaccine to their patients. These changes could be explained, at least partially, by the important effort done by public health authorities to disseminate information regarding A(H1N1) vaccination.

Why were Turks unwilling to accept the A/H1N1 influenza-pandemic vaccination? People's beliefs and perceptions about the swine flu outbreak and vaccine in the later stage of the epidemic

This study investigated the acceptability of the A/H1N1 influenza vaccination and related factors among 1137 adults in the later stage of the A/H1N1 outbreak in Turkey. Having already been vaccinated or intending to get vaccinated were related to trust in the vaccine effectiveness, perceived risk of the side effects, and benefits of getting vaccinated. Perceived long term consequences of the A/H1N1 infection, perceptions of the A/H1N1 information in media, and barriers for getting vaccinated were related to intention whereas anticipated epidemic situation in Turkey, being chronically ill, and being not married were related to having already been vaccinated.

Tracking parental attitudes on vaccination across European countries: The Vaccine Safety, Attitudes, Training and Communication Project (VACSATC)

The paper presents the first results from the European project VACSATC which aimed to track parental attitudes on vaccinations across several European countries. We compared five cross-sectional surveys of parents with children less than 3 years of age in England, Norway, Poland, Spain and Sweden carried out during 2008-2009. Data were collected from 6611 respondents. Two countries used face-to face interviews, one used telephone interviews, and two other countries used mail-in questionnaires. In all countries health professionals were indicated as the most important and trusted source of information on vaccination. The study results also show that parental attitudes on vaccinations in the childhood vaccination programs are generally positive. However, there were differences in attitudes on vaccination between the five countries, possibly reflecting different methods of sampling the respondents, context-specific differences (e.g. level of activity of governmental agencies), but also individual-level parental variation in demographic and socioeconomic status variables.