Internet Exposure Associated With Canadian Parents' Perception of Risk on Childhood Immunization: Cross-Sectional Study

Exploring social media influences on vaccine decision-making in parents: a netnography

Background

Immunization is one of the most significant health initiatives of recent times. Despite this, vaccine hesitancy is increasing and was listed as one of the top 10 threats to global health by the World Health Organization in 2019. A major factor associated with vaccine hesitancy is thought to be the viral spread of misinformation by a small but active anti-vaccination movement.

Objectives

The purpose of this study was to explore the influences of social media on vaccine decision-making in parents.

Design

This study is part of a larger body of research that explored vaccine decision-making in parents. Other methods included were an online survey and semi-structured interviews. This study investigated the influence of cyberculture on parents in an online environment.

Method

This study employed netnography, a form of qualitative inquiry with its roots in ethnography as methodology and a purpose-designed Facebook page as the means of exploring a purpose-designed online community with a particular focus on the culture, belief systems and influences present. Both manual and computer-assisted thematic analyses were used to analyse the data obtained.

Results

Three key themes were identified in this study. These included vaccine safety concerns, the emotional debate and COVID-19-specific issues. The results indicated the presence of strong anti-vaccination sentiment combined with an 'infodemic' of conspiracy theories, misinformation and vitriol with the potential to negatively impact parents seeking immunization information.

Conclusion

Given the popularity and accessibility of social media and the ready access to misinformation present online, it is evident that parental vaccine decision-making may be impacted adversely. Therefore, it is important that healthcare professionals are aware of this and provide adequate and timely education prior to parents seeking information on social media.

A Psychometric Study of the Arabic Version of the "Searching for Hardships and Obstacles to Shots (SHOT)" Instrument for Use in Saudi Arabia

Vaccines are considered one of the top 10 public health achievements of the 20th century and the most cost-effective public health intervention to overcome diseases and disease-associated mortality. This study translated the "Searching for Hardships and Obstacles to Shots" (SHOT) instrument from English to Arabic and conducted a psychometric evaluation of the Arabic version to measure parental barriers to childhood immunization. The cross-sectional study utilized multistage cluster random sampling to recruit parents visiting 70 primary health centers in Jizan. Scale translation and cultural adaptation were used to translate the SHOT survey into Arabic. The survey revealed that the best-factor model was a one-factor solution for "barriers to child immunization." The first principal component explained the highest variance (56.22%), and subsequent components explained decreasing percentages of variance. The third principal component explained the decreased variance (4.61%), and subsequent components explained the decreasing percentages of variance. The overall reliability (determined by Cronbach's alpha) was 0.96. The strong internal consistency of the Arabic version of the SHOT instrument (as indicated by the high Cronbach's alpha coefficients) indicates that researchers and practitioners can confidently use this scale to measure parents' attitudes toward and perceptions of vaccinations. Furthermore, the study results will help policymakers develop programs or interventional initiatives to overcome these barriers.

COVID-19 Vaccine-Related Information on the WeChat Public Platform: Topic Modeling and Content Analysis

BACKGROUND

The COVID-19 vaccine is an effective tool in the fight against the COVID-19 outbreak. As the main channel of information dissemination in the context of the epidemic, social media influences public trust and acceptance of the vaccine. The rational application of health behavior theory is a guarantee of effective public health information dissemination. However, little is known about the application of health behavior theory in web-based COVID-19 vaccine messages, especially from Chinese social media posts.

OBJECTIVE

This study aimed to understand the main topics and communication characteristics of hot papers related to COVID-19 vaccine on the WeChat platform and assess the health behavior theory application with the aid of health belief model (HBM).

METHODS

A systematic search was conducted on the Chinese social media platform WeChat to identify COVID-19 vaccine-related papers. A coding scheme was established based on the HBM, and the sample was managed and coded using NVivo 12 (QSR International) to assess the application of health behavior theory. The main topics of the papers were extracted through the Latent Dirichlet Allocation algorithm. Finally, temporal analysis was used to explore trends in the evolution of themes and health belief structures in the papers.

RESULTS

A total of 757 papers were analyzed. Almost all (671/757, 89%) of the papers did not have an original logo. By topic modeling, 5 topics were identified, which were vaccine development and effectiveness (267/757, 35%), disease infection and protection (197/757, 26%), vaccine safety and adverse reactions (52/757, 7%), vaccine access (136/757, 18%), and vaccination science popularization (105/757, 14%). All papers identified at least one structure in the extended HBM, but only 29 papers included all of the structures. Descriptions of solutions to obstacles (585/757, 77%) and benefit (468/757, 62%) were the most emphasized components in all samples. Relatively few elements of susceptibility (208/757, 27%) and the least were descriptions of severity (135/757, 18%). Heat map visualization revealed the change in health belief structure before and after vaccine entry into the market.

CONCLUSIONS

To the best of our knowledge, this is the first study to assess the structural expression of health beliefs in information related to the COVID-19 vaccine on the WeChat public platform based on an HBM. The study also identified topics and communication characteristics before and after the market entry of vaccines. Our findings can inform customized education and communication strategies to promote vaccination not only in this pandemic but also in future pandemics.

Psychological mechanisms and interventions directed at vaccination attitudes

Attitudes about vaccination impact not only the individual but also society. Therefore, understanding the underlying psychological processes of those who disagree with vaccination is critical for creating compassion through understanding and change through promoting autonomy. The current review aimed to fill a gap in the literature, outlining the state of the recent research on vaccination attitudes, specifically on the underlying mechanisms driving anti-vaccination movements and individuals' thoughts and behaviors. In addition, we aimed to evaluate current research on the effectiveness of interventions targeting these mechanisms. Overall, results indicated that those declining vaccines had beliefs related to distrust in the scientific community and pharmaceutical companies and moral preferences for purity and liberty. In addition, our review identified the potential for utilizing motivational interviewing techniques as an intervention. This literature review provides a platform for further research and enhances the current understanding of vaccination attitudes.

A systematic review of communication interventions for countering vaccine misinformation

BACKGROUND

Misinformation and disinformation around vaccines has grown in recent years, exacerbated during the Covid-19 pandemic. Effective strategies for countering vaccine misinformation and disinformation are crucial for tackling vaccine hesitancy. We conducted a systematic review to identify and describe communications-based strategies used to prevent and ameliorate the effect of mis- and dis-information on people's attitudes and behaviours surrounding vaccination (objective 1) and examined their effectiveness (objective 2).

METHODS

We searched CINAHL, Web of Science, Scopus, MEDLINE, Embase, PsycInfo and MedRxiv in March 2021. The search strategy was built around three themes(1) communications and media; (2) misinformation; and (3) vaccines. For trials addressing objective 2, risk of bias was assessed using the Cochrane risk of bias in randomized trials tool (RoB2).

RESULTS

Of 2000 identified records, 34 eligible studies addressed objective 1, 29 of which also addressed objective 2 (25 RCTs and 4 before-and-after studies). Nine 'intervention approaches' were identified; most focused on content of the intervention or message (debunking/correctional, informational, use of disease images or other 'scare tactics', use of humour, message intensity, inclusion of misinformation warnings, and communicating weight of evidence), while two focused on delivery of the intervention or message (timing and source). Some strategies, such as scare tactics, appear to be ineffective and may increase misinformation endorsement. Communicating with certainty, rather than acknowledging uncertainty around vaccine efficacy or risks, was also found to backfire. Promising approaches include communicating the weight-of-evidence and scientific consensus around vaccines and related myths, using humour and incorporating warnings about encountering misinformation. Trying to debunk misinformation, informational approaches, and communicating uncertainty had mixed results.

CONCLUSION

This review identifies some promising communication strategies for addressing vaccine misinformation. Interventions should be further evaluated by measuring effects on vaccine uptake, rather than distal outcomes such as knowledge and attitudes, in quasi-experimental and real-life contexts.

From Facebook to YouTube: The Potential Exposure to COVID-19 Anti-Vaccine Videos on Social Media

This article examines the role of Facebook and YouTube in potentially exposing people to COVID-19 vaccine-related misinformation. Specifically, to study the potential level of exposure, the article models a uni-directional information-sharing pathway beginning when a Facebook user encounters a vaccine-related post with a YouTube video, follows this video to YouTube, and then sees a list of related videos automatically recommended by YouTube. The results demonstrate that despite the efforts by Facebook and YouTube, COVID-19 vaccine-related misinformation in the form of anti-vaccine videos propagates on both platforms. Because of these apparent gaps in platform-led initiatives to combat misinformation, public health agencies must be proactive in creating vaccine promotion campaigns that are highly visible on social media to overtake anti-vaccine videos' prominence in the network. By examining related videos that a user potentially encounters, the article also contributes practical insights to identify influential YouTube channels for public health agencies to collaborate with on their public service announcements about the importance of vaccination programs and vaccine safety.

Does searching online for vaccination information affect vaccination coverage? Evidence from Sub-Saharan African countries

The Internet is reshaping the way people access health information. Over the past decades, an increasing number of people have been using the Internet to access vaccine-related information. Many studies suggest that the Internet can help improve people's understanding of health issues but at the same time facilitate the rapid spread of misinformation. This study explores the impact that searching the Internet for immunization information has on vaccination coverage. Using Google trends data, we found that access to online vaccination information has impacted vaccine uptake from 2004 to 2017, in Sub-Saharan African countries. The results indicate an overall positive impact on vaccine uptake. We also found that the effects are heterogeneous among vaccines. The effect is statistically significant for the vaccine related to high-risk disease, but not significant for the controversial vaccine and the vaccine related to low-risk disease.

Social Environmental Predictors of COVID-19 Vaccine Hesitancy in India: A Population-Based Survey

Background: During the ongoing COVID-19 pandemic, trust within a community in the projected schemes or strategies to combat COVID-19 depends on the confidence generated and launched by the government and medical employees toward the public. The “vaccination intention” within a community is determined by a range of factors, which include sociodemographic features, personal beliefs, and attitude toward vaccination. Methods: A nationwide survey was conducted involving 2000 people using a Tencent questionnaire platform. One-way ANOVA was conducted for age, education, and occupation with vaccination intention for the COVID-19 vaccine. Correlation analysis was conducted between sources, trust, and vaccination intention indicating both types of sources (official and unofficial sources) and both types of trust (trust in the social environment and in vaccines). Results: The reception of the sources of information on the COVID-19 vaccine was significantly higher from official sources (M = 5.54, SD = 1.37) and government officials (M = 5.68, SD = 1.499) compared with that from experts in medicine (M = 5.39, SD = 1.511). Among the unofficial sources, “chatting and communicating with family and friends” scored the highest (M = 4.84, SD = 1.649). In the statistics on people’s trust in all aspects involved in vaccines, the level of trust in the social environment was significantly higher and more concentrated than in vaccines (M = 5.67, SD = 1.129). The level of trust in government (M = 5.80, SD = 1.256) was slightly higher than in medical personnel (M = 5.53, SD = 1.199). People’s willingness to be vaccinated was generally high (M = 78.15, SD = 22.354). The demographic factors were not influential in vaccination intention. Both sources (official and unofficial sources) and trust (trust in the social environment and in vaccines) are significantly and positively correlated with vaccination intention. Information receptions from official and unofficial sources were significant positive predictors of trust in the social environment, but they were not significant predictors of trust in vaccines. The mediating effect of trust in vaccines on the relationship between receiving information from official and unofficial sources and vaccination intention was insignificant. Conclusions: This study revealed that trust in the environment is an important channel linking people’s information reception and vaccination intention, explores a new path for health information communication, and attempts to provide new ideas for health information dissemination and promotion.

Higher Collective Responsibility, Higher COVID-19 Vaccine Uptake, and Interaction with Vaccine Attitude: Results from Propensity Score Matching

Providing both personal and social benefits, vaccination may be motivated by collective responsibility (CR). Some previous studies have indicated the relationship between CR and vaccination but could not exclude confounding bias and had little knowledge about the boundary conditions. This study aimed to examine the association between CR and COVID-19 vaccine uptake and its boundary conditions in an extended version of the theory of planned behavior. A cross-sectional survey with 608 participants from six tourism satellite industries in Macao was conducted from 28 July 2021 to 20 August of 2021. Respondentss in CR-lower and CR-higher groups were 1:1 paired using propensity score matching (PSM) to control the potential confounding factors. Results showed participants in the CR-higher group reported significantly higher COVID-19 vaccine uptake than those in the CR-lower group (64.7% vs. 49.7%, p = 0.005). Multivariate logistic regression results indicated a positive association between CR and COVID-19 vaccine uptake (p = 0.012, OR = 2.070, 95% CI= 1.174 to 3.650) and its interaction effect with COVID-19 vaccine attitude (p = 0.019, OR = 0.922, 95% CI = 0.861 to 0.987). Spotlight analysis further illustrated that CR was more effective among individuals with a more negative COVID-19 vaccine attitude. These findings may help promote understanding of vaccine hesitancy, and hence optimize vaccination communication strategies during the COVID-19 pandemic.

Parental COVID-19 vaccine hesitancy: a cross-sectional survey in Italy

BACKGROUND

Understanding parents' hesitancy against COVID-19 vaccination for their children is useful.

METHODS

A self-administered online survey was conducted among 394 parents with at least one child aged 12-18 years in Italy.

RESULTS

The mean perceived risk that their child can be infected by the SARS-CoV-2, measured on a 10-point Likert-type scale, was 7.7 and it was higher if at least one parent/partner cohabitant have had COVID-19, in those who believed that COVID-19 is a serious illness, and in those who had not vaccinated their child. 82.1% respondents were willing to vaccinate their child and this was more likely among those who believed that this vaccine is useful and who did not need additional information. 12.4% were, according to the 5-item Parent Attitudes About Childhood Vaccines Survey (PACV-5) score, high-hesitant toward anti-COVID-19 vaccination. Respondents not graduated, those who did not believe that this vaccination was useful, those who did not get this vaccine, those who did not obtain information from physicians, and those who needed additional information were more likely to be high-hesitant.

CONCLUSIONS

Communication and public health interventions must be intensified to enhance the attitude and to help parents in deciding on COVID-19 vaccination of their children.

Using Machine Learning to Compare Provaccine and Antivaccine Discourse Among the Public on Social Media: Algorithm Development Study

BACKGROUND

Despite numerous counteracting efforts, antivaccine content linked to delays and refusals to vaccinate has grown persistently on social media, while only a few provaccine campaigns have succeeded in engaging with or persuading the public to accept immunization. Many prior studies have associated the diversity of topics discussed by antivaccine advocates with the public's higher engagement with such content. Nonetheless, a comprehensive comparison of discursive topics in pro- and antivaccine content in the engagement-persuasion spectrum remains unexplored.

OBJECTIVE

We aimed to compare discursive topics chosen by pro- and antivaccine advocates in their attempts to influence the public to accept or reject immunization in the engagement-persuasion spectrum. Our overall objective was pursued through three specific aims as follows: (1) we classified vaccine-related tweets into provaccine, antivaccine, and neutral categories; (2) we extracted and visualized discursive topics from these tweets to explain disparities in engagement between pro- and antivaccine content; and (3) we identified how those topics frame vaccines using Entman's four framing dimensions.

METHODS

We adopted a multimethod approach to analyze discursive topics in the vaccine debate on public social media sites. Our approach combined (1) large-scale balanced data collection from a public social media site (ie, 39,962 tweets from Twitter); (2) the development of a supervised classification algorithm for categorizing tweets into provaccine, antivaccine, and neutral groups; (3) the application of an unsupervised clustering algorithm for identifying prominent topics discussed on both sides; and (4) a multistep qualitative content analysis for identifying the prominent discursive topics and how vaccines are framed in these topics. In so doing, we alleviated methodological challenges that have hindered previous analyses of pro- and antivaccine discursive topics.

RESULTS

Our results indicated that antivaccine topics have greater intertopic distinctiveness (ie, the degree to which discursive topics are distinct from one another) than their provaccine counterparts (t₁₂₂=2.30, P=.02). In addition, while antivaccine advocates use all four message frames known to make narratives persuasive and influential, provaccine advocates have neglected having a clear problem statement.

CONCLUSIONS

Based on our results, we attribute higher engagement among antivaccine advocates to the distinctiveness of the topics they discuss, and we ascribe the influence of the vaccine debate on uptake rates to the comprehensiveness of the message frames. These results show the urgency of developing clear problem statements for provaccine content to counteract the negative impact of antivaccine content on uptake rates.

Online mis/disinformation and vaccine hesitancy in the era of COVID-19: Why we need an eHealth literacy revolution

The quality of online health information is cause for concern in general, and the spread of mis/disinformation on the benefits and risks of vaccines has certainly been fueling vaccine hesitancy. In the wake of the COVID-19 pandemic, we have entered an era of unprecedented “infodemic.” There has never been a more urgent time to address the long-standing question of how to overcome the deleterious influence of exposure to online mis/disinformation on vaccine uptake. eHealth literacy, a skill set including media literacy, is key to navigating the web in search for health information and processing the one encountered through social media. Studies assessing the impact of increasing eHealth literacy on behavioral attitudes and health outcomes in the general population are relatively scarce to date. Yet for many reasons, leveraging eHealth literacy skills, and more specifically, media literacy, could be of great value to help mitigate the detrimental effects of erroneous information on vaccination decision-making. In this paper, we make the case that eHealth and media literacies should be viewed as fundamental skills that have the potential to empower citizens to better recognize online mis/disinformation and make informed decisions about vaccination as any other health matters.

The feasibility, acceptability and preliminary efficacy of parent-targeted interventions in vaccination pain management of infants: a pilot randomized control trial (RCT)

Aim: To evaluate the feasibility, acceptability and preliminary efficacy of parent interventions for improving the use of pain management strategies during vaccination of infants, a two-armed pilot randomized control trial (RCT) was conducted. Materials & methods: 151 parents were randomized in two groups: Group 1) 'Be Sweet to Babies' videos and a tip sheet (n = 76); Group 2) As per Group 1 plus a motivational interviewing informed Affirmative Statements and Questions (AS&Q) (n = 75). Results & conclusion: Feasibility was evaluated by success of the recruitment (151 people in a week), rates of completed consent forms (85%), and surveys (59%). Over 94% satisfaction with interventions, processes and 88% intention to recommend the strategies to others determined the acceptability. Preliminary efficacy was evident by over 95% use of pain management strategies following the interventions. Clinical trial registration number: NCT03968432.

Parental Online Information Access and Childhood Vaccination Decisions in North America: Scoping Review

Background

Immunizing children throughout their early years prevents the spread of communicable disease and decreases the morbidity and mortality associated with many vaccine-preventable diseases. Searching online allows individuals rapid access to health information.

Objective

The purpose of this review was to develop an understanding of the existing literature of parents’ online health information-seeking behaviors to inform their vaccination choices for their children and to identify gaps in the literature around parents’ use of online health information and their vaccination choices.

Methods

A scoping review of peer-reviewed literature from Canada and the United States was performed. The following databases were utilized to perform the search: PubMed, CINAHL, Nursing & Allied Health Database, Scopus, and PsycINFO. The purpose of this review was to examine parents’ use of online information seeking related to vaccine information and to understand how parents utilize this information to inform decisions about vaccinating their children. Of the 34 papers included in the review, 4 relevant themes and subthemes were identified: information seeking, online information resources, online vaccine content, and trust in health care providers.

Results

Examination of the literature revealed conflicting information regarding parents’ use of social media and online resources to inform decisions around vaccinating their children. There is evidence of significant misinformation regarding vaccine risks online. Parents’ digital health literacy levels are unknown and may affect their ability to appraise online vaccination information.

Conclusions

Parents are seeking vaccine information from online sources. However, the influence of online vaccine information on parental vaccine practices remains uncertain.

Biased Sampling and Causal Estimation of Health-Related Information: Laboratory-Based Experimental Research

Background

The internet is a relevant source of health-related information. The huge amount of information available on the internet forces users to engage in an active process of information selection. Previous research conducted in the field of experimental psychology showed that information selection itself may promote the development of erroneous beliefs, even if the information collected does not.

Objective

The aim of this study was to assess the relationship between information searching strategy (ie, which cues are used to guide information retrieval) and causal inferences about health while controlling for the effect of additional information features.

Methods

We adapted a standard laboratory task that has previously been used in research on contingency learning to mimic an information searching situation. Participants (N=193) were asked to gather information to determine whether a fictitious drug caused an allergic reaction. They collected individual pieces of evidence in order to support or reject the causal relationship between the two events by inspecting individual cases in which the drug was or was not used or in which the allergic reaction appeared or not. Thus, one group (cause group, n=105) was allowed to sample information based on the potential cause, whereas a second group (effect group, n=88) was allowed to sample information based on the effect. Although participants could select which medical records they wanted to check—cases in which the medicine was used or not (in the cause group) or cases in which the effect appeared or not (in the effect group)—they all received similar evidence that indicated the absence of a causal link between the drug and the reaction. After observing 40 cases, they estimated the drug–allergic reaction causal relationship.

Results

Participants used different strategies for collecting information. In some cases, participants displayed a biased sampling strategy compatible with positive testing, that is, they required a high proportion of evidence in which the drug was administered (in the cause group) or in which the allergic reaction appeared (in the effect group). Biased strategies produced an overrepresentation of certain pieces of evidence at the detriment of the representation of others, which was associated with the accuracy of causal inferences. Thus, how the information was collected (sampling strategy) demonstrated a significant effect on causal inferences (F_1,185=32.53, P<.001, η^2p=0.15) suggesting that inferences of the causal relationship between events are related to how the information is gathered.

Conclusions

Mistaken beliefs about health may arise from accurate pieces of information partially because of the way in which information is collected. Patient or person autonomy in gathering health information through the internet, for instance, may contribute to the development of false beliefs from accurate pieces of information because search strategies can be biased.

Trend of influenza vaccine Facebook posts in last 4 years: a content analysis

BACKGROUND

Decreasing immunization rates may be partly due to antivaccine campaigns and other sources of misinformation available on social media, particularly on Facebook. Given the potential impact of this medium for communicating vaccine-related information, it is important to analyze the trend of information available on Facebook.

METHODS

We searched Facebook on August 15, 2018 to obtain posts containing relevant health information on influenza vaccine in years 2015-2018. We collected information regarding nature of the post (eg, pro-, antivaccine, and informational), number of shares and likes received, and ease of reading for each post. We evaluated these characteristics by year and type of post in our exploratory analyses.

RESULTS

The proportion of pro-vaccine posts has increased compared to antivaccine and informational posts since 2016. There was no correlation between ease of reading and popularity of posts. Although the language of antivaccine posts was complex, they were shared and liked more than pro-vaccine posts. The pro-vaccine personal post by a nurse was the most popular in our study (shared over 46,000 times) in 2018.

CONCLUSIONS

Though the number of pro-vaccine posts increased, antivaccine posts remained more popular. The government agency may use an emotive personal family-oriented message to promote vaccination.

Knowledge, Attitudes, and Practices towards Infectious Diseases Related to Travel of Community Pharmacists in Italy

Pharmacists should be educated about travel medicine, since they could influence their own choices and those of the individuals they encounter. This study aims to investigate the knowledge, attitudes, and behaviors towards infectious diseases related to travel among community pharmacists in Italy. The data was collected from September 2018 to September 2019 using semi-structured telephone interviews. Only 1.8% answered correctly to all seven questions regarding the infectious diseases related to travel. Community pharmacists who had heard about travel medicine and those who had received information were more likely to have good knowledge. More than two-thirds of the respondents believed that it is important to provide information to the public about travel medicine. Pharmacists who worked a higher number of hours per week, were more knowledgeable about the more frequent infectious diseases related to travel, believed that travel medicine was a pharmacist competency, believed that they could give advice to the public, and had received information from scientific journals and educational activities were more likely to have this positive attitude. More than two-thirds often/always informed the public about the importance of having travel health center counseling. Pharmacists who had heard about travel medicine and those who believed that they could give advice to the public were more likely to inform. Interventions are needed to improve knowledge in order that community pharmacists can play an active role in counseling the public.

Effectiveness and Parental Acceptability of Social Networking Interventions for Promoting Seasonal Influenza Vaccination Among Young Children: Randomized Controlled Trial

BACKGROUND

Seasonal influenza vaccination (SIV) coverage among young children remains low worldwide. Mobile social networking apps such as WhatsApp Messenger are promising tools for health interventions.

OBJECTIVE

This was a preliminary study to test the effectiveness and parental acceptability of a social networking intervention that sends weekly vaccination reminders and encourages exchange of SIV-related views and experiences among mothers via WhatsApp discussion groups for promoting childhood SIV. The second objective was to examine the effect of introducing time pressure on mothers' decision making for childhood SIV for vaccination decision making. This was done using countdowns of the recommended vaccination timing.

METHODS

Mothers of child(ren) aged 6 to 72 months were randomly allocated to control or to one of two social networking intervention groups receiving vaccination reminders with (SNI+TP) or without (SNI-TP) a time pressure component via WhatsApp discussion groups at a ratio of 5:2:2. All participants first completed a baseline assessment. Both the SNI-TP and SNI+TP groups subsequently received weekly vaccination reminders from October to December 2017 and participated in WhatsApp discussions about SIV moderated by a health professional. All participants completed a follow-up assessment from April to May 2018.

RESULTS

A total of 84.9% (174/205), 71% (57/80), and 75% (60/80) who were allocated to the control, SNI-TP, and SNI+TP groups, respectively, completed the outcome assessment. The social networking intervention significantly promoted mothers' self-efficacy for taking children for SIV (SNI-TP: odds ratio [OR] 2.69 [1.07-6.79]; SNI+TP: OR 2.50 [1.13-5.55]), but did not result in significantly improved children's SIV uptake. Moreover, after adjusting for mothers' working status, introducing additional time pressure reduced the overall SIV uptake in children of working mothers (OR 0.27 [0.10-0.77]) but significantly increased the SIV uptake among children of mothers without a full-time job (OR 6.53 [1.87-22.82]). Most participants' WhatsApp posts were about sharing experience or views (226/434, 52.1%) of which 44.7% (101/226) were categorized as negative, such as their concerns over vaccine safety, side effects and effectiveness. Although participants shared predominantly negative experience or views about SIV at the beginning of the discussion, the moderator was able to encourage the discussion of more positive experience or views and more knowledge and information. Most intervention group participants indicated willingness to receive the same interventions (110/117, 94.0%) and recommend the interventions to other mothers (102/117, 87.2%) in future.

CONCLUSIONS

Online information support can effectively promote mothers' self-efficacy for taking children for SIV but alone it may not sufficient to address maternal concerns over SIV to achieve a positive vaccination decision. However, the active involvement of health professionals in online discussions can shape positive discussions about vaccination. Time pressure on decision making interacts with maternal work status, facilitating vaccination uptake among mothers who may have more free time, but having the opposite effect among busier working mothers.

TRIAL REGISTRATION

Hong Kong University Clinical Trials Registry HKUCTR-2250; https://tinyurl.com/vejv276.

Searching Online for Information About Vaccination: Assessing the Influence of User-Specific Cognitive Factors Using Eye-Tracking

In Germany, the Internet is gaining increasing importance for laypeople as a source of health information, including information about vaccination. While previous research has focused on the characteristics of online information about vaccination, this study investigated the influence of relevant user-specific cognitive factors on users' search behavior for online information about vaccination. Additionally, it examined how searching online for information about vaccination influences users' attitudes toward vaccination. We conducted an experimental study with 56 undergraduate students from a German university that consisted of a survey and eye-tracking while browsing the Internet, followed by a content analysis of the eye-tracking data. The results show that the users exposed themselves to balanced and diverse online information about vaccination. However, none of the examined cognitive factors (attitude toward vaccination, attitude salience, prior knowledge about vaccination, need for cognition, and cognitive involvement) influenced the amount of time users spent searching the Internet for information about vaccination. Our study was not able to document any effects of attitude-consistent selective exposure to online information about vaccination. In addition, we found no effect on attitude change after having searched the Internet for vaccine-related information. Thus, users' search behavior regarding vaccination seems to be relatively stable.

Pre-vaccination screening strategies for the use of the CYD-TDV dengue vaccine: A meeting report

The first licensed dengue vaccine, CYD-TDV (Dengvaxia) is efficacious in seropositive individuals, but increases the risk for severe dengue in seronegative persons about two years after administration of the first dose. For countries considering the introduction of Dengvaxia, WHO recommends a pre-vaccination screening strategy whereby only persons with evidence of a past dengue infection would be vaccinated. Policy-makers need to consider the risk-benefit of vaccination strategies based on such screening tests, the optimal age to introduce the vaccine, communication and implementation strategies. To address these questions, the Global Dengue and Aedes-transmitted diseases Consortium (GDAC) organized a 3-day workshop in January 2019 with country representatives from Asia and Latin America. The meeting discussions highlighted many challenges in introducing Dengvaxia, in terms of screening test characteristics, costs of such tests combined with a 3-dose schedule, logistics, achieving high coverage rates, vaccine confidence and communication; more challenges than for any other vaccine introduction programme. A screening test would require a high specificity to minimize individual risk, and at the same time high sensitivity to maximize individual and population benefit. The underlying seroprevalence dependent positive predictive value is the best indicator for an acceptable safety profile of a pre-vaccination screening strategy. The working groups discussed many possible implementation strategies. Addressing the bottlenecks in school-based vaccine introduction for Dengvaxia will also benefit other vaccines such as HPV and booster doses for tetanus and pertussis. Levels of public trust are highly variable and context specific, and understanding of population perceptions and concerns is essential to tailor interventions, monitor and mitigate risks.

Knowledge, Attitudes, and Behaviors of Parents towards Recommended Adult Vaccinations: An Explanatory Survey in the Geographic Area of Naples, Italy

The purposes of this study were to explore the knowledge, attitudes, and behaviors towards the recommended vaccinations for adults between 19–64 years of age and the associated factors among parents. The survey was conducted from October to December 2018 among a sample of parents randomly selected from five preschools and primary, secondary, and high schools in the geographic area of Naples, Italy. The mean age of participants was 45.2 years (range 19–71). Only 16% of the parents knew all vaccinations recommended to adults between 19–64 years of age. Those being healthcare professionals, having a chronic condition, having received information about vaccinations from physicians, and having a lower educational level were more likely to know the vaccinations recommended to adults between 19–64 years of age. Female participants, those who had received information about vaccinations from physicians, and those who had a lower number of children were more likely to have a positive attitude toward the usefulness of the administration of vaccinations recommended to adults between 19–64 years of age. Among unvaccinated respondents, more than half reported a positive attitude toward willingness to receive a recommended vaccination. This positive attitude was significantly higher among those who considered vaccinations as being useful and among who had received information from physicians. Only 16.9% self-reported to have received at least one vaccination recommended to adults between 19–64 years of age. Those who were healthcare professionals, who had at least one chronic condition, and who considered the administration of the vaccinations as being useful were more likely to have received at least one recommended vaccination. Greater efforts by policy makers and healthcare providers are needed to increase parents’ knowledge on recommended vaccines, and it is also crucial that healthcare providers have a high knowledge and favorable attitudes in order to increase vaccine coverage.

User-Driven Comments on a Facebook Advertisement Recruiting Canadian Parents in a Study on Immunization: Content Analysis

BACKGROUND

More people are searching for immunization information online and potentially being exposed to misinformation and antivaccination sentiment in content and discussions on social media platforms. As vaccination coverage rates remain suboptimal in several developed countries, and outbreaks of vaccine-preventable diseases become more prevalent, it is important that we build on previous research by analyzing themes in online vaccination discussions, including those that individuals may see without actively searching for information on immunization.

OBJECTIVE

The study aimed to explore the sentiments and themes behind an unsolicited debate on immunization in order to better inform public health interventions countering antivaccination sentiment.

METHODS

We analyzed and quantified 117 user-driven open-ended comments on immunization posted in the Comments section of a Facebook advertisement that targeted Canadian parents for recruitment into a larger study on immunization. Then, 2 raters coded all comments using content analysis.

RESULTS

Of 117 comments, 85 were posted by unique commentators, with most being female (65/85, 77%). The largest proportion of the immunization comments were positive (51/117, 43.6%), followed by negative (41/117, 35.0%), ambiguous (20/117, 17.1%), and hesitant (5/117, 4.3%). Inaccurate knowledge (27/130, 20.8%) and misperceptions of risk (23/130, 17.7%) were most prevalent in the 130 nonpositive comments. Other claims included distrust of pharmaceutical companies or government agencies (18/130, 13.8%), distrust of the health care system or providers (15/130, 11.5%), past negative experiences with vaccination or beliefs (10/130, 7.7%), and attitudes about health and prevention (10/130, 7.7%). Almost 40% (29/74, 39%) of the positive comments communicated the risks of not vaccinating, followed by judgments on the knowledge level of nonvaccinators (13/74, 18%). A total of 10 positive comments (10/74, 14%) specifically refuted the link between autism and vaccination.

CONCLUSIONS

The presence of more than 100 unsolicited user-driven comments on a platform not intended for discussion, nor providing any information on immunization, illustrates the strong sentiments associated with immunization and the arbitrariness of the online platforms used for immunization debates. Health authorities should be more proactive in finding mechanisms to refute misinformation and misperceptions that are propagating uncontested online. Online debates and communications on immunization need to be identified by continuous monitoring in order for health authorities to understand the current themes and trends, and to engage in the discussion.

Fake News or Weak Science? Visibility and Characterization of Antivaccine Webpages Returned by Google in Different Languages and Countries

The 1998 Lancet paper by Wakefield et al., despite subsequent retraction and evidence indicating no causal link between vaccinations and autism, triggered significant parental concern. The aim of this study was to analyze the online information available on this topic. Using localized versions of Google, we searched “autism vaccine” in English, French, Italian, Portuguese, Mandarin, and Arabic and analyzed 200 websites for each search engine result page (SERP). A common feature was the newsworthiness of the topic, with news outlets representing 25–50% of the SERP, followed by unaffiliated websites (blogs, social media) that represented 27–41% and included most of the vaccine-negative websites. Between 12 and 24% of websites had a negative stance on vaccines, while most websites were pro-vaccine (43–70%). However, their ranking by Google varied. While in Google.com, the first vaccine-negative website was the 43rd in the SERP, there was one vaccine-negative webpage in the top 10 websites in both the British and Australian localized versions and in French and two in Italian, Portuguese, and Mandarin, suggesting that the information quality algorithm used by Google may work better in English. Many webpages mentioned celebrities in the context of the link between vaccines and autism, with Donald Trump most frequently. Few websites (1–5%) promoted complementary and alternative medicine (CAM) but 50–100% of these were also vaccine-negative suggesting that CAM users are more exposed to vaccine-negative information. This analysis highlights the need for monitoring the web for information impacting on vaccine uptake.

Investigating Italian parents' vaccine hesitancy: A cross-sectional survey

This cross-sectional survey was designed to assess the prevalence of vaccine hesitancy and to identify factors associated among a randomly selected sample of parents. A questionnaire was self-administered from October to December 2017 to a sample of parents of children aged 2 to 6 years attending five randomly selected pre-schools in the geographic area of Naples, Italy. Out of the 727 selected parents, 437 returned the questionnaires for a response rate of 60.1%. The median of Parent Attitudes about Childhood Vaccines Survey (PACV) score among participants was 45.8 with a total of 141 parents (34.7%) scored a value ≥50 and were defined hesitant about the childhood vaccinations. Vaccine hesitancy was significantly more common among those who were concerned and among those were not sure that any one of the childhood shots might not be safe, among those who were concerned that their children might have a serious side effect from a shot, among those who were concerned that a shot might not prevent the disease, among those who delayed and refused at least a shot of vaccine for their children, and in those who are not sure and uncertain in the pediatrician. More than half of parents (53.8%) expressed a desire to receive additional information about the childhood vaccinations. Parents who were not sure and uncertain that to follow the recommended shot schedule is a good idea for their children and those who were parents of first-born children were more likely to need additional information. This study finds a high prevalence of vaccine hesitancy among parents suggesting that in the immunization program is necessary to achieve a higher quality of the relationship between pediatricians and the community.