Confidence about vaccines in the United States: understanding parents' perceptions

Access to Vaccination Information and Confidence/Hesitancy Towards Childhood Vaccination: A Cross-Sectional Survey in China

Access to vaccination information could influence public attitudes towards vaccination. This study investigated the number and types of vaccination-related information sources, and estimated their associations with vaccine confidence and hesitancy in China. In January 2019, we conducted a cross-sectional survey in China, and 2122 caregivers with children <6 years completed self-administered questionnaires. Logistic regressions were used to assess associations between caregivers’ primary information sources and vaccine confidence/hesitancy. A majority (72%) of caregivers had multiple sources of vaccination-related information. The proportions of caregivers reporting professional sources, media, and peers as primary information sources were 81%, 63%, and 26%. Internal migrants were less likely to get information from professional sources; more educated and wealthier caregivers reported more information sources and were more likely to get information from media and peers. Caregivers who reported professional information sources had significantly higher odds of being confident about the safety of vaccines and lower odds of being hesitant toward vaccination than those who did not. Caregivers who reported the media as a primary information source had significantly higher odds of being hesitant toward vaccination than those who did not. To address vaccine hesitancy, it is essential to promote universal access to professional vaccination-related information sources, and to use the media to disseminate evidence-based information and clarify misinformation. Health communication should target internal migrants, and more educated and wealthier caregivers.

Ethical and policy implications of vaccinomics in the United States: community members' perspectives

Objectives: We aimed to elucidate public values regarding the use of genomics to improve vaccine development and use (vaccinomics).

Methods: Adults ≥18 years-old were recruited through social media and community organizations, and randomly assigned to one of four nested discussion groups in Boulder, CO and Baltimore, MD. Participants rated their confidence in vaccine safety and effectiveness prior to and after discussing vaccinomics. Before departing, they prioritized funding for vaccinomics versus federal priorities (vaccine safety and efficacy, new vaccines, and free vaccines) and chronic diseases (cancer, heart disease, and diabetes). Grounded Theory-influenced methods were used to identify themes.

Results: Participants broadly supported vaccinomics. Emergent themes: concerns about reduced privacy/confidentiality, increased genetically based stigma/discrimination, and reduced agency to make vaccine-related decisions through genetically based prioritization. Participants supported vaccinomics’ potential for increased personalization. Some participants favored prioritizing others over themselves during a vaccine shortage, while others did not. Some participants worried health insurance companies would discriminate against them based on information discovered through vaccinomics. Participants feared inequitable implementation of vaccinomics would contribute to discrimination and marginalization of vulnerable populations. Discussing vaccinomics did not impact perceptions of vaccine safety and effectiveness. Federal funding for vaccinomics was broadly supported.

Conclusion: Participants supported vaccinomics’ potential for increased personalization, noting policy safeguards to facilitate equitable implementation and protect privacy were needed. Despite some concerns, participants hoped vaccinomics would improve vaccine safety and effectiveness. Policies regarding vaccinomics’ implementation must address public concerns about the privacy and confidentiality of genetic information and potential inequities in access to vaccinomics’ benefits.

Assessment of Vaccine Hesitancy to a COVID-19 Vaccine in Cameroonian Adults and Its Global Implication

Since the outbreak of COVID-19 in December 2019, no global consensus treatment has been developed and generally accepted for the disease. However, eradicating the disease will require a safe and efficacious vaccine. In order to prepare for the eventual development of a safe and efficacious COVID-19 vaccine and to enhance its uptake, it is imperative to assess vaccine hesitancy in Cameroonians. After obtaining ethical clearance from the Institutional Review Board of the University of Buea, a questionnaire was administered (May–August 2020) to consenting adults either online or in person. A qualitative thematic analysis was done to analyze the participants’ answers to the open questions. A deductive approach was used, that is, the codes and patterns according to the World Health Organization (WHO) Strategic Advisory Group of Experts (SAGE) Working Group Matrix of Determinants of vaccine hesitancy. The number of consenting adult Cameroonians who completed the questionnaire were 2512 (Two thousand five hundred and twelve). Vaccine hesitancy to a COVID-19 vaccine was 84.6% in Cameroonians. Using the WHO recommended Matrix of Determinant of Vaccine hesitancy, the most prominent determinants observed in this study were: Communication and Media Environment, Perception of pharmaceutical industry, Reliability and/or source of vaccine and cost. Most Cameroonians agree that even though there are benefits of a clinical trial, they will prefer it should be done out of the continent and involving African scientists for eventual acceptance and uptake. The concerns of safety, efficacy and confidence has to be addressed using a Public Engagement approach if a COVID-19 vaccine has to be administered successfully in Africa or Cameroon specifically. Since this study was carried out following WHO standards, its result can be compared to those of other studies carried out in different cultural settings using similar standards.

Social amplification of risk and "probable vaccine damage": A typology of vaccination beliefs in 28 European countries

BACKGROUND

Despite lacking scientific support, vaccine hesitancy is widespread. While serious vaccine damage as a scientific fact is real yet statistically highly uncommon, emerging social and technological forces have amplified perceptions of risk for "probable vaccine damage", making it a widely shared intersubjective reality.

METHODS

Using the Eurobarometer 91.2 survey on a statistically representative EU27-UK sample interviewed in March 2019, we documented perceptions of vaccine risks and identified three belief configurations regarding vaccine effectiveness, safety, and usefulness, through exploratory cluster analysis.

RESULTS

The public beliefs in significant vaccine risks are frequent. Approximatively one-tenth of the EU27-UK population consider that vaccines are not rigorously tested before authorization, one-third believe that vaccines can overload or weaken the immune system and that they can cause the disease against which they protect, and almost one-half believe that vaccines can cause serious side effects. We identified three belief configurations: hesitant, confident, and trade-off clusters. The hesitant type (approx. 11% of EU27-UK respondents) is defined by the perception that vaccines are rather ineffective, affected by risks of probable vaccine damage, not well-tested, and useless; the confident type (approx. 59%) is defined by beliefs that vaccines are effective, safe, well-tested, and useful; and the trade-off type (approx. 29%) combines beliefs that vaccines are effective, well-tested and useful, with perceptions of probable vaccine damage. The vaccine-confident and the trade-off types have similar vaccination histories, indicating the significant role of other factors besides beliefs in inducing behavior.

CONCLUSIONS

The high proportion of varying public beliefs in significant vaccine risks and the presence of a trade-off type of vaccination assessment indicate the social normality of beliefs in probable vaccine damage. Communication campaigns should take into account the social normality of the perceived risk of "probable vaccine damage" across various social types, and patterns of concomitant trust and mistrust in vaccination.

Unfolding the Determinants of COVID-19 Vaccine Acceptance in China

Background

China is at the forefront of global efforts to develop COVID-19 vaccines and has five fast-tracked candidates at the final-stage, large-scale human clinical trials testing phase. Vaccine-promoting policymaking for public engagement is a prerequisite for social mobilization. However, making an informed and judicious choice is a dilemma for the Chinese government in the vaccine promotion context.

Objective

In this study, public opinions in China were analyzed via dialogues on Chinese social media, based on which Chinese netizens’ views on COVID-19 vaccines and vaccination were investigated. We also aimed to develop strategies for promoting vaccination programs in China based on an in-depth understanding of the challenges in risk communication and social mobilization.

Methods

We proposed a novel behavioral dynamics model, SRS/I (susceptible-reading-susceptible/immune), to analyze opinion transmission paradigms on Chinese social media. Coupled with a meta-analysis and natural language processing techniques, the emotion polarity of individual opinions was examined in their given context.

Results

We collected more than 1.75 million Weibo messages about COVID-19 vaccines from January to October 2020. According to the public opinion reproduction ratio (R₀), the dynamic propagation of those messages can be classified into three periods: the ferment period (R₀₁=1.1360), the revolution period (R₀₂=2.8278), and the transmission period (R₀₃=3.0729). Topics on COVID-19 vaccine acceptance in China include price and side effects. From September to October, Weibo users claimed that the vaccine was overpriced, making up 18.3% (n=899) of messages; 38.1% (n=81,909) of relevant topics on Weibo received likes. On the contrary, the number of messages that considered the vaccine to be reasonably priced was twice as high but received fewer likes, accounting for 25.0% (n=53,693). In addition, we obtained 441 (47.7%) positive and 295 (31.9%) negative Weibo messages about side effects. Interestingly, inactivated vaccines instigated more heated discussions than any other vaccine type. The discussions, forwards, comments, and likes associated with topics related to inactivated vaccines accounted for 53% (n=588), 42% (n=3072), 56% (n=3671), and 49% (n=17,940), respectively, of the total activity associated with the five types of vaccines in China.

Conclusions

Most Chinese netizens believe that the vaccine is less expensive than previously thought, while some claim they cannot afford it for their entire family. The findings demonstrate that Chinese individuals are inclined to be positive about side effects over time and are proud of China’s involvement with vaccine development. Nevertheless, they have a collective misunderstanding about inactivated vaccines, insisting that inactivated vaccines are safer than other vaccines. Reflecting on netizens’ collective responses, the unfolding determinants of COVID-19 vaccine acceptance provide illuminating benchmarks for vaccine-promoting policies.

Experiences with tick exposure, Lyme disease, and use of personal prevention methods for tick bites among members of the U.S. population, 2013-2015

Consistent and effective use of personal prevention methods for tickborne diseases, including Lyme disease (LD), is dependent on risk awareness. To improve our understanding of the general U.S. population's experiences with tick exposure and use of personal prevention methods, we used data from ConsumerStyles, a web-based, nationally representative questionnaire on health-related topics. Questions addressed tick bites and LD diagnosis in the last year, use of personal prevention methods to prevent tick bites, and willingness to receive a theoretical LD vaccine. Of 10,551 participants surveyed over three years, 12.3 % reported a tick bite for themselves or a household member in the last year, including 15.4 % of participants in high LD incidence (LDI) states, 16.3 % in states neighboring high LDI states, and 9.4 % in low LDI states. Participants in high LDI states and neighboring states were most likely to use personal prevention methods, though 46.6 % of participants in high LDI states and 53.9 % in neighboring states reported not using any method. Participants in low LDI states, adults ≥ 75 years of age, those with higher incomes, and those living in urban housing tended to be less likely to practice personal prevention methods. Likeliness to receive a theoretical LD vaccine was high in high LDI (64.5 %), neighboring (52.5 %), and low LDI (49.7 %) states. Targeted educational efforts are needed to ensure those in high LDI and neighboring states, particularly older adults, are aware of their risk of LD and recommended personal prevention methods.

Strengthening Vaccine Confidence and Acceptance in the Pediatric Provider Office

Although vaccine acceptance and uptake are overall high among children in the United States, vaccine delays or refusals are a growing concern. Vaccine hesitancy is a challenge for the pediatric provider, given the diverse factors associated with hesitancy and the limited evidence on effective strategies for addressing vaccine hesitancy in the provider office. In this article, we review available evidence and approaches for vaccine communication, including the importance of using a whole-team approach, building trust, starting the conversation early, using a presumptive approach for vaccine recommendations, motivational interviewing with parents who have concerns for vaccines, and additional techniques for responding to parent questions. We also review organizational strategies to help create a culture of immunization in the practice, including evidence-based approaches for increasing vaccine uptake and efficiency. Although these communication approaches and organizational strategies are intended to reassure parents who are vaccine hesitant that all routine, universally recommended vaccines are safe and effective, they likely will take on increased significance as the development, implementation, and evaluation of coronavirus disease 2019 vaccines continue to unfold. [Pediatr Ann. 2020;49(12):e523-e531.].

Parental vaccine attitudes, beliefs, and practices: initial evidence in California after a vaccine policy change

Senate Bill 277 (SB277) eliminated nonmedical exemptions for school-entry vaccines in California, but the impact of parental vaccine knowledge, attitudes, and beliefs on vaccine decision-making has not been extensively examined within the post-SB277 context. This study generates preliminary understanding and discussion of the vaccination knowledge, attitudes, and beliefs among a pilot population of parents of kindergarten students in California after the implementation of SB277. School officials administered a cross-sectional survey to parents of kindergarten children in California from April to July 2019. Parents reported their perceptions of diseases and vaccines, key immunization beliefs, and confidence in different sources of vaccine information. Most parents (92%) had fully vaccinated their children post-SB277 and generally perceived vaccines to be safe and effective, but about 44% reported they were hesitant about childhood vaccines. The majority of parents (87%) rated vaccine information from their doctor as highly credible. This pilot group of kindergarten parents was generally supportive of vaccination and had fully vaccinated their children, but most parents still harbored concerns and misconceptions about vaccines and about public health authorities. This indicates a disconnect between parental vaccine compliance and confidence, and suggests that educational interventions could impact parental vaccine behavior and decision-making.

Web-Based Tailored Messaging to Increase Vaccination: A Randomized Clinical Trial

BACKGROUND

To increase vaccine acceptance, we created a Web-based the "Vaccines and Your Baby" intervention (VAYB) that provided new parents with vaccine information messages tailored to vaccine beliefs and values. We evaluated the effectiveness of the VAYB by comparing timely uptake of infant vaccines to an untailored version of the intervention (UT) or usual care intervention (UC) only.

METHODS

Between April 2016 and June 2019, we conducted a randomized clinical trial. Pregnant women and new parents were randomly assigned to the VAYB, UT, or UC arms. In the VAYB and UT arms, participants were exposed to interventions at 4 time points from pregnancy until their child was 15 months of age. The primary outcome was up-to-date status for recommended vaccines from birth to 200 days of age. A modified intent-to-treat analysis was conducted. Data were analyzed with logistic regression to generate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

We enrolled 824 participants (276 VAYB, 274 UT, 274 UC), 143 (17.4%) of whom were lost to follow-up. The up-to-date rates in the VAYB, UT, and UC arms were 91.44%, 92.86%, and 92.31%, respectively. Infants in the VAYB arm were not more likely to be up to date than infants in the UC arm (OR = 0.89; 95% CI, 0.45-1.76) or in the UT arm (OR = 0.82; 95% CI, 0.42-1.63). The odds of being up to date did not differ between UT and UC arms (OR = 1.08; 95% CI, 0.54-2.18).

CONCLUSIONS

Delivering Web-based vaccine messages tailored to parents' vaccine attitudes and values did not positively impact the timely uptake of infant vaccines.

Maternal and paternal confidence in vaccine safety: Whose attitudes are predictive of children's vaccination?

Relatively little is known about the differential impact of maternal and paternal perceptions of vaccine safety on children's vaccination status in New Zealand. Using a sample of 68 couples from the New Zealand Attitudes and Values Study (NZAVS), the present study investigated the distinct influence of mothers' and fathers' confidence in the safety of childhood vaccinations following the national immunisation schedule on their reports of children's vaccination status. Actor-Partner Interdependence Modelling revealed that mothers', but not fathers', vaccine confidence predicted children's vaccination status, regardless of who reported their children's vaccination status. Higher maternal vaccine confidence increased the likelihood of child full vaccination status, but paternal vaccine confidence showed no unique significant effects. As women tend to express lower vaccine confidence than men, it is imperative to further investigate the key drivers of their low confidence and develop target interventions accordingly. Encouraging fathers' involvement in the vaccination decision-making process may also be beneficial in increasing the likelihood of childhood vaccination uptake.

Resources for assessing parents' vaccine hesitancy: a systematic review of the literature

The concept of Vaccine Hesitancy has begun to appear in the scientific landscape, referring to the reluctance of a growing proportion of people to accept the vaccination offer. A variety of factors were identified as being associated with vaccine hesitancy but there was no universal algorithm and currently there aren’t any established metrics to assess either the presence or impact of vaccine hesitancy. The aim of this study was to systematically review the published questionnaires evaluating parental vaccine hesitancy, to highlight the differences among these surveys and offer a general overview on this matter. This study offers a deeper perspective on the available questionnaires, helping future researches to identify the most suitable one according to their own aim and study setting.

The problem of vaccination refusal: a review with guidance for pediatricians

PURPOSE OF REVIEW

In the wake of multiple recent outbreaks of the measles and other vaccine-preventable diseases, it is crucial to understand and address parental concerns about vaccination. The purposes of this review are: to identify the causes of vaccine resistance, to elucidate the variables that have led to the success or failure of interventions to date, and to consider implications for pediatricians treating children whose parents are vaccination-resistant.

RECENT FINDINGS

Recent research draws on insights from cognitive science to understand vaccine resistance and to develop more effective interventions. Studies show that vaccine resistors are more likely to value lifestyle liberty, to favor individualistic over hierarchical worldviews, and to believe in conspiracy theories. Interventions that seek primarily to correct erroneous beliefs about the dangers of vaccination are likely to fail or even backfire. On the other hand, intervention strategies, such as motivational interviewing, in which the provider elicits and shows respect for parents' values and concerns while empowering them to make well informed and well reasoned decisions, are more likely to be successful. Parents cite a trusting relationship with their pediatrician as the most important factor influencing their decision to vaccinate.

SUMMARY

Pediatricians are in the best position to successfully apply insights from cognitive science and intervention research to overcome vaccination-hesitancy.

Evaluation of a Vaccine-Communication Tool for Physicians

OBJECTIVES

To evaluate a Kaiser Permanente Northern California physician training tool entitled "Effective Communication without Confrontation" aimed at improving communication with vaccine-hesitant parents, building trust, and alleviating physician stress surrounding vaccination visits.

STUDY DESIGN

Trainings were held May to July 2015. Pre- and post-training surveys assessed physician comfort and perceived effectiveness in communicating with vaccine-hesitant parents. We measured vaccination coverage at the 2-, 4-, and 6-month well-child visits, and days undervaccinated at 9 months of age. We compared vaccination rates before and after the training.

RESULTS

Of 415 physicians who received training, 249 completed post-training surveys. Physicians reported that the training helped them feel "much more or more" comfortable talking with parents who are unsure (72.3%), want to delay (73.9%), or refuse (63.5%) vaccinations and "much more or more" effective at persuading parents who are unsure (67.5%) or want to delay vaccinations (61.4%). They reported feeling "the same or less" effective persuading parents who refuse vaccinations (66.3%). Vaccine coverage remained unchanged and high from before to after the training (95%-96%), as did parent satisfaction with his or her child's provider (4.73/5.00).

CONCLUSIONS

The Effective Communication without Confrontation training did not increase vaccine coverage, but did improve physicians' comfort and perceived effectiveness communicating with most vaccine-hesitant parents and may help to ease potentially stressful vaccination visits.

Shouting at each other into the void: A linguistic network analysis of vaccine hesitance and support in online discourse regarding California law SB277

In 2015, California passed Senate Bill 277 and became the third state in the United States to ban all nonmedical exemptions from school immunization requirements, effectively prohibiting religious and personal belief exemptions. This attracted grassroots opposition and considerable debate among vaccine hesitant factions online. This mixed-methods study used quantitative linguistic analysis, semantic network analysis, and content analysis techniques to examine 2424 online documents drawn from newspapers, blogs, health websites, government information pages, web forums, personal websites, Facebook groups, among others. The study examined which words and phrases were used most frequently by vaccine skeptics, vaccine defenders, and more neutral media accounts to illuminate how groups with different attitudes towards vaccination discuss and disseminate information about vaccines and vaccine policy online. We proposed an innovative methodology for examining online discourse surrounding vaccine hesitance, as well as for studying the online dissemination of misinformation about vaccines. Our findings highlighted discrepancies in the narratives between what vaccine supporters believe causes vaccine skepticism and the issues that vaccine skeptics actually discuss within their own digital spaces. For example, in these exchanges, the importance of parental rights overshadowed that of children's rights; supporters of vaccines brought up autism in more distinct documents than skeptics do; distrust of government regulators and researchers seemed to unite vaccine skeptics and defenders; and politicians, doctors, and even celebrities often served as proxies in heated exchanges about factual evidence, believability, and the importance of expertise in public discourse.

The use of the health belief model to assess predictors of intent to receive the COVID-19 vaccine and willingness to pay

BACKGROUND

The development of a vaccine against SARS-CoV-2 infection is on the way. To prepare for public availability, the acceptability of a hypothetical COVID-19 vaccine and willingness to pay (WTP) were assessed to provide insights into future demand forecasts and pricing considerations.

METHODS

A cross-sectional survey was conducted from 3 to 12 April 2020. The health belief model (HBM) was used to assess predictors of the intent to receive the vaccine and the WTP.

RESULTS

A total of 1,159 complete responses was received. The majority reported a definite intent to receive the vaccine (48.2%), followed by a probable intent (29.8%) and a possible intent (16.3%). Both items under the perceived benefits construct in the HBM, namely believe the vaccination decreases the chance of infection (OR = 2.51, 95% CI 1.19-5.26) and the vaccination makes them feel less worry (OR = 2.19, 95% CI 1.03-4.65), were found to have the highest significant odds of a definite intention to take the vaccine. The mean ± standard deviation (SD) for the amount that participants were willing to pay for a dose of COVID-19 vaccine was MYR$134.0 (SD±79.2) [US$30.66 ± 18.12]. Most of the participants were willing to pay an amount of MYR$100 [US$23] (28.9%) and MYR$50 [US$11.5] (27.2%) for the vaccine. The higher marginal WTP for the vaccine was influenced by no affordability barriers as well as by socio-economic factors, such as higher education levels, professional and managerial occupations and higher incomes.

CONCLUSIONS

The findings demonstrate the utility of HBM constructs in understanding COVID-19 vaccination intention and WTP.

The impact of parents' health behaviours on their preferences regarding vaccinations in Bialystok, Poland

BACKGROUND

Currently, as the number of vaccinated children in Poland and throughout Europe is decreasing. Many factors impact on the rate vaccination and parents' health behaviours may affect the frequency of vaccinations. The aim of the study was to assess the association of parents' health behaviors with children's vaccinations.

METHODS

A cross-sectional survey was conducted from July 2015 to June 2016 to assess to assess the association of parents' health behaviors with children's vaccinations in Białystok city, Poland. We used the the Inventory of Health Behaviours and an original questionnaire including demographic data and questions about vaccination. Three hundred parents were recruited from the Pro Medica Family Medica Center in Bialystok, Poland.

RESULTS

Only 3.7% of respondents did not vaccinate their children. The level of health behaviours was average in 42.3% of the respondents, low in 33%, and high in 24.7%. Significant differences in health behaviours, mainly the level of normal eating habits (p = 0.038) and positive mental attitude (p = 0.022), were found in relation to views on the toxicity of vaccines. Participants who reported that vaccines can cause autism engaged in a higher level of prophylactic behaviours. Respondents who vaccinated their children with combined vaccines had a significantly higher level of health practices.

CONCLUSIONS

Parents preferred health behaviours did not effect on children vaccination. Parents who believed in the toxicity of vaccines were more concerned about proper nutrition, had a positive mental attitude, and engaged in a higher level of preventive behaviours and health practices. Parents who did not vaccinate their children had lower levels of normal eating habits. Parents who vaccinated their children with combined vaccines had a higher level of health behaviours, especially in terms of health practices.

Parents' Perspectives about Vaccine Hesitancies and Vaccine Rejection, in the West of Turkey

PURPOSE

The aim of this study was to evaluate Turkish parents' perspectives on childhood vaccines.

DESIGN AND METHODS

614 parents of the children between the ages of 0-14 years were included in the study for examining their perspectives about vaccine hesitation and rejection. Age, gender, educational level, number of children, and income levels of volunteer participants were recorded. In addition to the personal data, a questionnaire form with questions about vaccines and vaccination was prepared.

RESULTS

The mean age of the participants was found as 37.20 ± 6.84 years (range, 21 to 53). The rate of vaccine hesitancy was found to be statistically significantly and higher in men. A statistically higher number of women were affected by the opinions of the individuals around them related to vaccines. Moreover, the rate of hearing any negative information about vaccines increased as the level of education increased. The impact of an increase in the number of children and the income level of the participants on the survey parameters were evaluated and significant relationships were observed.

CONCLUSIONS

Vaccine rejection is a significant public health problem in the world and will continue to be the case in the world.

PRACTICE IMPLICATIONS

In our country, it has been determined that men's hesitation rates are higher and women are more affected by the environment. Necessary trainings should be planned in this regard. Also, as the level of education affects opinions of the vaccine, many plans are needed to increase the level of education.

Who or What Influences the Individuals' Decision-Making Process Regarding Vaccinations?

Thanks to vaccines, many people are not exposed to the risks associated with vaccine-preventable diseases (VPDs). This, however, results in growing popularity of antivaccine movements and affects global and local epidemiological situation. Vaccine hesitancy has become a significant problem not only for epidemiologists but also for practitioners. Fortunately, the hesitant group seems to be vulnerable to intervention, and studies indicate that these patients can be persuaded to undergo vaccinations. The aim of the present study was to determine the factors most strongly affecting vaccination-related attitudes and decisions. An anonymous, self-administered survey consisting of demographic data and single select multiple-choice questions regarding vaccination was conducted. The voluntary study included secondary school pupils, medical and nonmedical students, healthcare professionals, hospital and clinic patients as well as parents. A total of 7950 survey forms were distributed between January 2018 and June 2019 in south-eastern Poland. A total of 6432 respondents (80.2%) completed a questionnaire that was eligible for analysis. The positive attitude toward vaccination was significantly affected by older age, by the fact of obtaining information on vaccinations from a physician, this information's higher quality (assessed in school grade scale), higher level of knowledge on vaccines and by the fact of denying the association between vaccination and autism in children (p < 0.001). The probability of supporting vaccinations was almost eight-fold lower among respondents believing the vaccine-autism relationship. Chance of supporting vaccination doubled in the group with a higher knowledge level. The individuals not provided with expert information on vaccination were twice as often unconvinced. Age, education and having children significantly affected the attitude toward influenza immunization (p < 0.001). Older, better educated respondents and those having children were more positive about vaccinations. The medical community still exert decisive effects on attitudes toward vaccinations. High-quality information provided by them is of great importance. Skillful and competent provision of evidence-based information disproving the myth about vaccine-autism connection and proper education of medical staff is essential in molding positive attitudes toward vaccinations.

Lithuanians' perceptions of vaccination and their sources of information: a literature review

OBJECTIVES

Attitudes toward vaccination are important drivers of vaccination decisions and behavior. But researchers have pointed to the shortage of such studies on Eastern Europe.

METHODS

A literature review of 14 survey studies was conducted.

RESULTS

The review showed that Lithuanians' attitudes toward vaccines appear to be volatile with considerable discrepancy between views about the importance of vaccines and their perceived effectiveness and safety. Perceptions of vaccine risks are high, with Lithuanians challenging both specific vaccines (children's, flu) and vaccination in general. Lithuanians' perceptions of vaccine importance are among the lowest in the EU (23rd out of 28 countries).

CONCLUSIONS

Lithuanians do not entirely reject vaccines, but many are worried about their health impact. More studies are needed to explore vaccine perceptions in Lithuania and potential factors shaping those, like media representations.

Applying lessons from vaccination hesitancy to address birth dose Vitamin K refusal: Where has the trust gone?

Refusal of intramuscular Vitamin K at birth is an emerging public health issue resulting in increased rates of intracranial bleeding. Parents who refuse this intervention bear epidemiologic resemblance to vaccine-refusing parents, are geographically clustered and share a mistrust of public health interventions. We review the prevalence of Vitamin K refusal and discuss individual and societal recommendations that may reduce Vitamin K refusal, adapted from vaccine hesitancy literature. We note the prevalence of misinformation on social media as a contributor to refusal and explore how changes in healthcare practices may influence growing physician mistrust. We propose solutions to the issue including state-based mandates and a pervasive social media strategy to combat misinformation as a contributor to Vitamin K refusal.

Implementation of a motivational interviewing-based decision tool to improve childhood vaccination rates: Pilot study protocol

BACKGROUND

Parental concerns regarding the safety and efficacy of vaccines have been on the rise over the past decade, resulting in a decline in comprehensive vaccine coverage in children. Healthcare practitioners face many challenges when recommending childhood vaccinations, with many parents refusing vaccination due to these and other concerns. Effective communication strategies and tools can equip providers to communicate with vaccine hesitant parents, but validated tools are currently lacking.

OBJECTIVES

This study aims to develop a validated parental communication tool utilizing motivational interviewing to increase vaccination adherence in children ages 6 years and younger.

METHODS

The MOTIVE (Motivational Interviewing Tool to Improve Vaccination Adherence) tool will first be developed based on the most recent literature regarding vaccine hesitancy and related health beliefs. Following tool development, the tool will be reviewed via an external review process to ensure practicality of the tool for use in clinical practice. In implementing the MOTIVE tool, providers and clinic staff will be trained regarding vaccine hesitancy and motivational interviewing. The tool will then be implemented in routine well-child appointments. The primary outcome of this study is the percentage of children 0-6 years of age completing all recommended doses of the core vaccine series after implementation of the MOTIVE tool as compared to prior vaccination years. Secondary outcomes will also include parental attitudes towards vaccines and provider knowledge regarding motivational interviewing components and vaccine hesitancy.

PROJECT IMPACT

Following completion of this study, the MOTIVE tool will be made available for other providers for use in their own clinical practice. The availability of effective communication tools will allow healthcare providers to engage in productive conversations regarding vaccination, aiming to increase vaccine uptake.

Psychological reactance impacts ratings of pediatrician vaccine-related communication quality, perceived vaccine safety, and vaccination priority among U.S. parents

Physician communication surrounding vaccination is important in driving patient compliance with schedules and recommendations, but patient psychological factors suggest that communication strategies may have differential effects on patients. This paper investigates how psychological reactance, defined as an individuals' propensity to restore their autonomy when they perceive that others are trying to impose their will on them, impacts perceptions about physician communication and perceptions and prioritizations of vaccination. We propose and describe the results of a study that was conducted to assess the relationship between individual differences in reactance, perceived quality of pediatrician communication, perceptions of vaccination safety, and vaccination prioritization using a sample of parents. We recruited 300 parent participants via the online platform Prolific Academic in which they completed a computer-mediated survey. Results show that compared to those who are low in psychological reactance, those high in psychological reactance place less of a priority on vaccination, and that this relationship is driven by evaluations of physician communication quality and perceived vaccine safety. Our findings suggest that physicians should not adopt a one-size-fits-all approach when interacting with patients and should tailor messaging to patients based on psychological factors including reactance.

The state of vaccine safety science: systematic reviews of the evidence

This Review updates the scientific evidence assessing possible causal associations of adverse events following immunisation (AEFI) compiled in the 2012 report from the Institute of Medicine and the 2014 report from the Agency for Healthcare Research and Quality. For 12 of 46 AEFI examined, a causal relationship has been established with at least one vaccine currently routinely recommended to the general USA population: anaphylaxis, arthralgia or arthritis (mild, acute, and transient, not chronic), deltoid bursitis (when vaccine is administered improperly), disseminated varicella infection (in immune deficient individuals for whom the varicella vaccine is contraindicated), encephalitis, febrile seizures, Guillain-Barré syndrome, hepatitis (in immune deficient individuals for whom the varicella vaccine is contraindicated), herpes zoster, immune thrombocytopenic purpura, meningitis, and syncope. Other than mild acute and transient arthralgia or arthritis, which is very common in adult women after rubella vaccine, these adverse reactions are rare or very rare. Vaccines have an excellent safety profile overall and provide protection against infectious diseases to individuals and the general population.

"I can be the Judge of What's Serious": A Qualitative Pilot Study of Parents' Responses to Messaging About Side Effects of the HPV Vaccine

OBJECTIVE

Parents' concerns about vaccine safety and side effects likely contribute to low rates of human papillomavirus (HPV) vaccination among adolescents. To facilitate parent-provider discussions about the HPV vaccine, we developed and tested the content of a clinical decision support application for implementation in pediatric clinical settings. This study sought to elicit perspectives of parents and providers on the best way to communicate information on vaccine side effects.

METHODS

To understand the acceptability of the application's content, we conducted focus groups with parents (n = 11) and providers (n = 9) at three primary care clinics. Focus groups transcriptions were analyzed using iterations of deductive and inductive coding, with independent coding by two trained reviewers to improve inter-rater reliability.

RESULTS

Surprisingly, when parents reviewed screen shots of HPV vaccine safety and side effect messages, parents took exception to the expression "no evidence of serious side effects". Parents wanted side effects listed explicitly so they could decide for themselves which side effects were "serious". Parents also felt that the HPV vaccine did have serious side effects, and the wording undermined their trust in the vaccine messaging overall. Providers accepted the phrasing of side effects and did not express concerns that parents would object to the messaging.

CONCLUSIONS

Further research is needed to confirm parents' concerns with the phrasing "no serious side effects" for the HPV vaccine and to assess the impact on HPV vaccination deferral or delay.

Adherence to Timely Vaccinations in the United States

OBJECTIVES

To estimate (1) the proportion of children not adhering to the Advisory Committee on Immunization Practices (ACIP) recommended early childhood immunization schedule and (2) associations between schedule adherence, sociodemographic characteristics, and up-to-date immunization status by 19 to 35 months of age.

METHODS

We used 2014 National Immunization Survey provider-verified vaccination data to classify vaccination patterns as "recommended" (ie, in line with ACIP dose- and age-specific recommendations), "alternate" (ie, in line with either limiting the number of shots per visit or skipping at least 1 vaccine series), or "unknown or unclassifiable" (ie, not in line with ACIP recommendations or clearly limiting shots per visit or vaccine series). We evaluated the association between vaccination patterns and up-to-date status for all ACIP-recommended vaccinations (including rotavirus and hepatitis A vaccines) using Poisson regression.

RESULTS

The majority of children's patterns were classified as "recommended" (63%), with 23% and 14% following alternate or unknown or unclassifiable patterns, respectively; 58% of children were up-to-date with all ACIP-recommended immunizations by 19 to 35 months. Not being up-to-date was associated with alternate (prevalence ratio = 4.2, 95% confidence interval: 3.9-4.5) and unknown or unclassifiable (prevalence ratio = 2.4, 95% confidence interval: 2.2-2.7) patterns.

CONCLUSIONS

High vaccine coverage by 19 to 35 months of age may miss nonadherence to the recommended immunization schedule in the first 18 months of life, leaving children vulnerable to preventable diseases. With more than one-third of US children not following the ACIP schedule, targeted interventions are needed to minimize vaccine delays and disease susceptibility.

Characterizing the vaccine knowledge, attitudes, beliefs, and intentions of pregnant women in Georgia and Colorado

Vaccine coverage for maternal vaccines is suboptimal; only about half of pregnant women received influenza and Tdap vaccines in 2018. We explored knowledge, attitudes, beliefs, intentions, and trust regarding maternal and infant vaccines among pregnant women. Between June 2017 and July 2018, we surveyed 2196 pregnant women recruited from geographically and socio-demographically diverse prenatal care practices in Georgia and Colorado (56% response rate). Fifty-six percent of pregnant women intended to receive both influenza and Tdap vaccines during pregnancy and 68% intended to vaccinate their baby with all recommended vaccines on time. Attitudinal constructs associated with intention to vaccinate include confidence in vaccine safety (ORs: 16–38) and efficacy (ORs: 4–19), perceived risk of vaccine-preventable diseases (ORs: 2–6), social norms (ORs: 4–10), and trust in sources of vaccine information. Women pregnant with their first child were less likely than women who had prior children to intend to vaccinate themselves and their children, more likely to be unsure about their intentions to receive both maternal and infant vaccines, and less likely to report feeling they had enough knowledge or information about vaccines and vaccine safety (p < .01). This demonstrates an opportunity for vaccine education to increase vaccine confidence and informed decision-making, especially among first-time pregnant women.

Vaccine exemption requirements and parental vaccine attitudes: an online experiment

Increases in vaccine hesitancy and vaccine-preventable disease outbreaks have focused attention on state laws governing school-entry vaccine mandates and the allowable exemptions (medical and nonmedical) from those mandates. There is substantial variation in the type of exemptions available in each state, and states with more rigorous or burdensome exemption requirements generally have lower exemption rates. States have little evidence, however, about how vaccine-hesitant parents respond to different requirements. Despite recent efforts to formulate "model legislation" templates for states to follow, policy evidence about optimal exemption regimes is limited to observational studies in states that have changed exemption laws. We conducted two online experiments to explore how parental attitudes and intentions responded to different school-entry vaccine mandate exemption requirements. We randomly assigned online participants to one of four hypothetical vaccine exemption application scenarios: parental signature only, a checklist of vaccines for which an exemption is requested, a lengthy (10-30+ min) video-based vaccine education module, and a requirement to write a statement justifying the exemption. Among parents with high vaccine hesitancy, a required vaccine education module led to significant decreases in vaccine hesitancy, while checklist and justification requirements increased vaccine hesitancy slightly. Among parents with low vaccine hesitancy, we observed a potential backfire effect when parents were required to write a justification statement. Our findings warrant replication in a larger, fully-powered trial to accelerate knowledge about how parents across the vaccine hesitancy spectrum respond to exemption regimes.

Exploring the relationship between newspaper coverage of vaccines and childhood vaccination rates in Spain

Background: Despite the effectiveness of vaccines being well established and recognized by the research community, eleven European countries have adopted mandatory vaccination programs because of vaccine hesitancy. Lack of information and fake news are considered the main reasons. The media are a powerful tool for spreading vaccine-related information. The study of media effects on vaccine uptake has received little attention in Europe.Objective: To explore the association of childhood vaccination rates in Spain with vaccine-related coverage in print media.Methods: A content analysis of newspaper coverage of vaccines was conducted. The study variables were: national vaccination rates, article publication dates, tone and main theme of the articles. We conducted a correlation analysis to assess the association between media coverage and childhood vaccine uptake.Results: While vaccine coverage with positive and neutral tones significantly increased during the study period (p < .001), the number of articles with a negative tone remained unchanged (p = .306). There was a significant and inverse correlation between negative newspaper coverage and childhood vaccine uptake (r = -.771, p < .05). During 2016 and 2017, although the media reporting declined, vaccination rates kept increasing. The most frequent themes were about the development of the Ebola vaccine, and the chickenpox and meningitis vaccine crises.Conclusions: Our findings expand the understanding of media role on vaccination and suggest that the media need to be considered as an important player during vaccination campaigns. The study points to the important educational role of the media in public health.

Understanding the impact of state vaccination laws on exemption rates

PURPOSE OF REVIEW

This review summarizes the current state of school-entry vaccination requirements and related exemption policies in the United States and examines recent changes to these policies.

RECENT FINDINGS

With recent infectious disease outbreaks in the United States, there has been heightened awareness on unvaccinated individuals, and the state-level policies that allow individuals to be exempted from school-entry vaccination requirements. Between 2015 and 2017, there have been eleven states that have altered their policies regarding school-entry vaccination requirements and related reporting for which no formal evaluations have been published. One policy change during that period, California SB 277, which became law in 2016, reduced the nonmedical exemption and increased the childhood vaccination coverage rate in that state, though with some evidence of exemption replacement through the use of medical exemptions. Through September 2019, five additional state law changes have been enacted.

SUMMARY

The large number of heterogeneous changes to state-level policies for school-entry vaccination requirements in recent years need rigorous evaluation to identify best practices for balancing public health authority and parental autonomy while seeking to achieve the highest level of infectious disease prevention for children.

Previsit Screening for Parental Vaccine Hesitancy: A Cluster Randomized Trial

OBJECTIVE

To evaluate the effect of vaccine hesitancy screening on childhood vaccine uptake.

METHODS

We conducted a cluster randomized controlled trial in pediatric primary care clinics in Washington state. Vaccine-hesitant parents (VHPs) with a healthy newborn receiving health supervision at participating clinics were eligible. VHPs were identified by using a 4-item version of the validated Parent Attitudes About Childhood Vaccines Survey (PACV). Before their child's 2- and 6-month health supervision visits, VHPs at intervention clinics completed the 15-item PACV embedded in a survey containing placebo items. Intervention providers received a summary of parents' 15-item PACV responses and interpretation of their PACV score; discretion was given to providers regarding how they acted on this information. VHPs at control clinics completed only the placebo survey items, and their child's provider received a summary of their responses; control providers remained blinded to parent VHP status. Our outcome was child immunization status at 8 months of age expressed as percent of days underimmunized. We compared outcomes in control and intervention participants using t test and linear mixed-effects regression.

RESULTS

We enrolled 24 clinics (12 in each arm) and 156 parents (65 in the intervention arm). Parent characteristics were similar across arms except more intervention (versus control) parents had a first-born child (60.9% vs 44%; P = .04). No significant difference in outcome was detected between arms (25.2% [95% confidence interval: 16.0% to 34.5%] vs 19.1% [95% confidence interval: 12.0% to 26.3%] mean days underimmunized in the intervention and control arms, respectively).

CONCLUSION

Vaccine hesitancy screening was not significantly associated with days underimmunized.

Health Information Sources, Perceived Vaccination Benefits, and Maintenance of Childhood Vaccination Schedules

Parental concerns over the safety or necessity of childhood vaccination have increased over the past decades. At the same time, there has been a proliferation of vaccine-related information available through a range of health information sources. This study investigates the associations between evaluations of health information sources, parental perceptions of childhood vaccination benefits, and the maintenance of vaccination schedules for their children. Specifically, this study aims to (a) incorporate social media into the battery of health information sources and (b) differentiate households with a childhood autism diagnosis and those without, given unsubstantiated but persistent concerns about vaccine safety and autism. Analyzing a sample of U.S. households, a total of 4,174 parents who have at least one child under the age of 18 were analyzed, including 138 of parents of households with a childhood autism diagnosis. Results show that the more the parents value interpersonal communication and magazines as sources of health information, the more they perceive vaccination benefits, and the more the value they put on television, the better they keep vaccination schedules up-to-date for their children. On the other hand, social media are negatively associated with their perceptions of vaccination benefits. Although parents of children diagnosed with autism are less likely to perceive vaccination benefits, no interaction effects with evaluations of health information sources are found on parental perceptions of vaccination benefits or maintenance of schedules.

MomsTalkShots: An individually tailored educational application for maternal and infant vaccines

INTRODUCTION

The development and initial assessment in a clinical setting of a theory-driven, individually tailored educational application (app), MomsTalkShots, focused on increasing uptake of maternal and infant vaccines is described.

METHODS

MomsTalkShots algorithmically tailored videos based on parent needs to deliver an intervention that was specifically responsive to individual vaccine attitudes, beliefs and intentions, demographics, and source credibility. MomsTalkShots was evaluated among 1103 pregnant women recruited from 23 geographically and socio-demographically diverse obstetrician-gynecologist offices in Georgia and Colorado in 2017. Self-reported information needs were assessed pre-and post-videos and participants self-reported factors related to usability and analyzed in 2018.

RESULTS

The vast majority of women reported MomsTalkShots was helpful (95%), trustworthy (94%), interesting (97%) and clear to understand (99%), none of which varied by demographics or parity. Reported usability was slightly lower among vaccine hesitant women, yet the majority reported MomsTalkShots was helpful (91%), trustworthy (85%), interesting (97%) and clear (99%). The majority of women (72%) who did not have enough vaccine information pre-videos reported enough information post-videos.

CONCLUSIONS

MomsTalkShots was designed to provide individually tailored vaccine information to pregnant women from a population with varied vaccine intentions, confidence and vaccine concerns. MomsTalkShots was extremely well-received among pregnant women, even among women who were initially vaccine hesitant and did not intend to vaccinate themselves and their infants according to the recommended immunization schedule. Next steps include evaluation to assess impact on vaccine uptake and expansion to adolescent and adult vaccines.

Addressing personal parental values in decisions about childhood vaccination: Measure development

OBJECTIVE

Evidence-based strategies to address vaccine hesitancy are lacking. Personal values are a measurable psychological construct that could be used to deliver personalized messages to influence vaccine hesitancy and behavior. Our objectives were to develop a valid, reliable self-report survey instrument to measure vaccine values based on the Schwartz theory of basic human values, and to test the hypothesis that vaccine values are distinct from vaccine attitudes and are related to vaccine hesitancy and behavior.

METHODS

Parental Vaccine Values (PVV) scale items were generated using formative qualitative research and expert input, yielding 24 items for testing. 295 parents of children aged 14-30 months completed a self-report survey with measures of Schwartz's global values, the PVV, vaccine attitudes, and vaccine hesitancy. Factor analysis was used to determine vaccine values factor structure. Associations between vaccine values, vaccine attitudes, vaccine hesitancy, and vaccination behavior were assessed using linear and logistic regression models. Late vaccination was assessed from electronic medical records.

RESULTS

A six-factor structure for vaccine values was determined with good fit (RMSEA = 0.07, Bentler's CFI = 0.91) with subscales for Conformity, Universalism, Tradition, Self-Direction, Security- Disease Prevention, and Security- Vaccine Risk. Vaccine values were moderately associated with Schwartz global values and vaccine attitudes, indicating discriminant validity from these constructs. Multivariable linear regression showed vaccine hesitancy was associated with vaccine values Conformity (partial R² = 0.10) and Universalism (0.04) and vaccine attitudes Vaccine Safety (0.52) and Vaccine Benefit (0.16). Multivariable logistic regression showed that late vaccination was associated with vaccine value Self-direction (OR = 1.80, 95% CI: 1.26-2.65) and vaccine attitude of Vaccine Benefit (OR = 0.44, 95% CI: 0.32-0.60).

CONCLUSIONS

The PVV scale had good psychometric properties and appears related to but distinct from Schwartz global values and vaccine attitudes. Vaccine values are associated with vaccine hesitancy and late vaccination and may be useful in tailoring future interventions.

Educating healthcare providers to increase Human Papillomavirus (HPV) vaccination rates: A Qualitative Systematic Review

Objectives

HPV vaccination rates in the United States lag behind other developed countries. Educational interventions are primarily directed at patients and parents rather than healthcare providers (HCPs), despite evidence that provider recommendation is a key determinant of vaccine uptake. The objectives for this review are to synthesize the available evidence related to the knowledge, attitudes, and beliefs of HCPs surrounding HPV vaccination, to summarize provider-specific educational interventions which have been evaluated, and to review existing provider-specific educational resources from national organizations and whether they align with the gaps identified.

Methods

A systematic search was performed using PubMed, Web of Science, CINAHL, and ERIC with MeSH terms human papillomavirus, vaccine, education, workshop, training, knowledge, attitude, belief, intention, and healthcare provider. Full text articles were obtained for studies that described the knowledge and attitudes of providers and/or impact of educational interventions. Data extraction was performed by four independent reviewers. Websites of American organizations with an interest in HPV vaccination were manually searched for provider resources.

Results

1066 publications were identified, and 98 articles were fully reviewed with 40 ultimately included. Providers’ knowledge on HPV was generally low with a correspondingly low vaccine recommendation rate. Provider-specific education (e.g., didactic session and communication training) with complimentary interventions demonstrated increased knowledge and vaccine series initiation and completion. Themes identified in descriptive studies highlighted providers’ lack of general HPV and vaccine knowledge, low self-confidence in counselling and addressing parental concerns, and discomfort in discussing sexual issues related to vaccination. Many American organizations have provider-specific resources; however, the effectiveness of these materials has not been established.

Conclusions

HPV knowledge among providers remains low. Educational interventions to improve knowledge and communication appear to be effective. A breadth of resources from national organizations are available but their efficacy and level of utilization is largely unknown. Coordinated efforts are needed to evaluate provider-specific educational resources to improve vaccine uptake in the US.

Sentiment Analysis of Social Media on Childhood Vaccination: Development of an Ontology

BACKGROUND

Although vaccination rates are above the threshold for herd immunity in South Korea, a growing number of parents have expressed concerns about the safety of vaccines. It is important to understand these concerns so that we can maintain high vaccination rates.

OBJECTIVE

The aim of this study was to develop a childhood vaccination ontology to serve as a framework for collecting and analyzing social data on childhood vaccination and to use this ontology for identifying concerns about and sentiments toward childhood vaccination from social data.

METHODS

The domain and scope of the ontology were determined by developing competency questions. We checked if existing ontologies and conceptual frameworks related to vaccination can be reused for the childhood vaccination ontology. Terms were collected from clinical practice guidelines, research papers, and posts on social media platforms. Class concepts were extracted from these terms. A class hierarchy was developed using a top-down approach. The ontology was evaluated in terms of description logics, face and content validity, and coverage. In total, 40,359 Korean posts on childhood vaccination were collected from 27 social media channels between January and December 2015. Vaccination issues were identified and classified using the second-level class concepts of the ontology. The sentiments were classified in 3 ways: positive, negative or neutral. Posts were analyzed using frequency, trend, logistic regression, and association rules.

RESULTS

Our childhood vaccination ontology comprised 9 superclasses with 137 subclasses and 431 synonyms for class, attribute, and value concepts. Parent's health belief appeared in 53.21% (15,709/29,521) of posts and positive sentiments appeared in 64.08% (17,454/27,236) of posts. Trends in sentiments toward vaccination were affected by news about vaccinations. Posts with parents' health belief, vaccination availability, and vaccination policy were associated with positive sentiments, whereas posts with experience of vaccine adverse events were associated with negative sentiments.

CONCLUSIONS

The childhood vaccination ontology developed in this study was useful for collecting and analyzing social data on childhood vaccination. We expect that practitioners and researchers in the field of childhood vaccination could use our ontology to identify concerns about and sentiments toward childhood vaccination from social data.

Vaccine Information Sources and Parental Trust in Their Child's Health Care Provider

BACKGROUND

Parental trust in their child's health care provider and the number and type of vaccine information sources are important dimensions of vaccine hesitancy and may suggest intervention components for future research.

METHOD

We conducted secondary analysis of survey data from mothers of healthy newborns in Washington State, and examined the association between parental trust in their child's health care provider and vaccine information sources.

RESULTS

We found that mothers with less trust in their child's health care provider used more sources, more informal sources, and were less likely to consider their child's pediatrician their main source of vaccine information compared with more trusting mothers. However, less trusting mothers did not report more effort to read or watch stories about vaccines than more trusting mothers, nor were they more likely to report the internet as their main vaccine information source.

CONCLUSIONS

Future interventions seeking to reduce parental vaccine hesitancy should consider intervention components focused on building or improving parent trust in their child's health care provider.

Japanese anti- versus pro-influenza vaccination websites: a text-mining analysis

Anti-vaccination sentiment exists worldwide and Japan is no exception. Health professionals publish pro-influenza vaccination messages online to encourage proactive seeking of influenza vaccination. However, influenza vaccine coverage among the Japanese population is less than optimal. The contents of pro- and anti-influenza vaccination websites may contribute to readers' acceptance of one or the other position. We aimed to use a text-mining method to examine frequently appearing content on websites for and against influenza vaccination. We conducted online searches in January 2017 using two major Japanese search engines (Google Japan and Yahoo! Japan). Targeted websites were classified as 'pro', 'anti' or 'neutral' depending on their claims, with author(s) classified as 'health professionals', 'mass media' or 'laypersons'. Text-mining analysis was conducted, and statistical analysis was performed using a chi-squared test. Of the 334 websites analyzed, 13 content topics were identified. The three most frequently appearing content topics on pro-vaccination websites were vaccination effect for preventing serious cases of influenza, side effects of vaccination, and efficacy rate of vaccination. The three most frequent topics on anti-vaccination websites were ineffectiveness of influenza vaccination, toxicity of vaccination, and side effects of vaccination. The main disseminators of each topic, by author classification, were also revealed. We discuss possible tactics of online influenza vaccination promotion to counter anti-vaccination websites.

Mandatory Health Care Provider Counseling For Parents Led To A Decline In Vaccine Exemptions In California

Receipt of childhood vaccinations in the US has been declining, and outbreaks of preventable infectious diseases have become more common. In response, in 2014 California implemented a policy change for exemptions from mandatory vaccines for school enrollment. Data on fifteen successive cohorts of kindergarteners enrolled in public and private schools between school years 2001-02 and 2015-16 were analyzed for changes in vaccination trends. The results show an increase in the prevalence and clustering of vaccine exemptions from 2001-02 through 2013-14, followed by a modest decline after implementation of a policy mandating health care provider counseling for vaccine exemption. Clustering of vaccine exemptions increased over the study period and was less responsive to the policy change than were exemption rates overall. Nor did the policy change uniformly reduce the clustering of at-risk students across counties. Trends in the use of conditional admission showed strong school-level clustering and remained relatively stable. The policy change was effective at reducing exemption rates but did not uniformly reduce clustering of exemptions. The results suggest the need to evaluate the causes of local-area clustering and to adopt a statewide policy that addresses clustering of vaccine exemptions within schools and counties.

The impact of rare but severe vaccine adverse events on behaviour-disease dynamics: a network model

The propagation of rumours about rare but severe adverse vaccination or infection events through social networks can strongly impact vaccination uptake. Here we model a coupled behaviour-disease system where individual risk perception regarding vaccines and infection are shaped by their personal experiences and the experiences of others. Information about vaccines and infection either propagates through the network or becomes available through globally available sources. Dynamics are studied on a range of network types. Individuals choose to vaccinate according to their personal perception of risk and information about infection prevalence. We study events ranging from common and mild, to severe and rare. We find that vaccine and infection adverse events have asymmetric impacts. Vaccine (but not infection) adverse events may significantly prolong the tail of an outbreak. Similarly, introducing a small risk of a vaccine adverse event may cause a steep decline in vaccine coverage, especially on scale-free networks. Global dissemination of information about infection prevalence boosts vaccine coverage more than local dissemination. Taken together, these findings highlight the dangers associated with vaccine rumour propagation through scale-free networks such as those exhibited by online social media, as well as the benefits of disseminating public health information through mass media.

A visual content analysis of vaccine coverage in the print media

Visual imagery is essential in the media and is broadly recognised to increase attention, recall information, improve comprehension and even change adherence to clinical guidelines. Despite the social debate about vaccination, the study of vaccine media images has received little attention. Therefore, this study aims to analyse the visual content of newspaper coverage of vaccines and to identify some key patterns that might be more likely to influence audience understanding. Coverage from 2012 to 2017 about vaccines was retrieved from the flagship Spanish newspapers El Pais and El Mundo. An imagery content analysis was undertaken for 131 articles. Results reveal that images are commonly used in the print media, appearing in 56% (n = 74) of articles about vaccines. Images were mostly located in the top area of the page (p < .001), and each image occupied about 28% of the total surface in the page. Each article included 1 image on average, and 76% (n = 64) of visual resources were photography and the frames 'human interest' and 'conflict' were the most frequent ones. The themes of the images focused most commonly on the action of vaccination, vaccines as such, the biological aspects of the vaccine and research. The study provides descriptive knowledge related to the use of visual contents coverage about vaccines in the print media. We suggest further research on the influence of visual contents in the context of vaccines as well as a collaboration between public health experts and designers to create effective visual contents and messages.