Chinese social media suggest decreased vaccine acceptance in China: An observational study on Weibo following the 2018 Changchun Changsheng vaccine incident

Solving a Controversial Health Problem May Be Tricky: Examining Social Media News Use, Gender, Fear, and Information Behaviors in HPV Prevention

Guided by the Situational Theory of Problem Solving (STOPS), this study surveys 1,853 Chinese individuals to identify factors influencing active information behaviors and HPV prevention intentions. Results show that involvement recognition is the key driver of situational motivation, leading to active information behaviors, which in turn significantly predict HPV vaccination intentions. Although fear does not directly impact information behaviors, it mediates the effect of perceptual variables on situational motivation. The study also highlights the different impacts of Chinese versus foreign social media news consumption on perceptual variables and the unique effect of gender on involvement recognition. These findings support the applicability of STOPS in HPV prevention and provide insights for improving health communication strategies.

Can social media promote vaccination? Strategies and effectiveness of COVID-19 vaccine popularization on Chinese Weibo

Background

The COVID-19 pandemic has shown a high severity in terms of mortality, and to mitigate the impact of the COVID-19 pandemic, a great deal of reliance has been placed on vaccines with defensive effects. In the context of the transmission of hazardous Omicron variant strains, vaccine popularization and acceptance are very important to ensure world health security. Social media can spread information and increase public confidence in and acceptance of vaccines.

Method

In this study, weibos related to "vaccine science popularization" during the COVID-19 pandemic in China were collected, and Weibo publishers were divided into Individuals, Organizations, Media, Government, and Scientists. The communication strategies were analyzed with content analysis from the four dimensions of Issue, Topic, Frame, and Position. SnowNLP was used to mine the audience comments and to assess their emotional tendencies. Finally, hierarchical regression was used to verify the causal relationship between vaccine science popularization strategies and audiences' emotions.

Results

We found that the higher the scientific authority of the weibo publisher, the more positive the emotional tendency of the audience toward the weibo. Issues that are scientific, authoritative, and positive topics that positively present the advantages of the COVID-19 vaccine, and frames with detailed narratives, scientific arguments, diversified forms of presentations, and positions in support of the COVID-19 vaccine, positively affect the effect of vaccine popularization.

Discussion

Based on the experience of COVID-19 vaccine promotion in China, the results may serve as a reference for promoting innovative vaccines and handling public health affairs around the world.

Acceptance of Human Papillomavirus (HPV) vaccine among the parents of eligible daughters (9-15 years) in Bangladesh: A nationwide study using Health Belief Model

BACKGROUND

To align with the 2030 vision of the World Health Organization (WHO) to ensure 90% of girls receive the HPV vaccine before turning 15, Bangladesh has recently started the (HPV) vaccine campaign nationwide. Therefore, our study aimed to assess the level of its acceptance among parents of eligible daughters in Bangladesh.

METHODS

This nationwide cross-sectional study was conducted among the self-identified parents of daughters in the age group of 9-15 years between June 28 and August 2, 2023. A total of 2,151 parents were conveniently selected from all eight divisions of Bangladesh. Data was collected through face-to-face interviews using a semi-structured questionnaire. The Health Belief Model was used to appraise respondents' beliefs concerning HPV and its vaccination. Adjusted odds ratios (AOR) with a corresponding 95% confidence interval (CI), and a p-value of <0.05 was considered statistically significant. R Studio (Version 2023.09.0+463) was used as an interface for data analysis, while R (the programming language) was used for statistical computations.

RESULTS

The mean age of the study participants was 38.18 (±5.86) years. The overall acceptance rate of the HPV vaccine was 86.61% (95%CI: 85.09-88.02). The vaccine acceptance level was positively associated with all the domains of the HBM (p<0.001), except in the perceived barrier domain (p = 0.489). After adjustment for other factors, it was found that higher age was associated with a decreased acceptance (AOR: 0.92; 95% CI: 0.89-0.95). The urban residents exhibited 42% lower odds of vaccine acceptance than rural (AOR: 0.58; 95% CI: 0.36-0.92). Similarly, participants of the middle-income group had 44% lower odds than the lower-income group (AOR: 0.56; 95% CI: 0.32-0.97).

CONCLUSION

Our study found a reasonably good level of acceptance of the HPV vaccine among the parents of eligible daughters. Multiple factors such as younger age, urban residence, belonging to the middle income group, history of regular routine health check-ups, knowledge of cervical cancer, positive perception about benefits of the vaccine, and positive cues to actions were associated with HPV vaccine acceptance.

Determinants of parental demand of human papillomavirus vaccination for adolescent daughters in China: Contingent valuation survey

BACKGROUND

Several types of human papillomavirus (HPV) vaccines have been approved for use in adolescent girls in China. These vaccines are regulated as non-National Immunisation Program vaccines and are optional and generally fully self-paid by vaccinees.

OBJECTIVE

To assess parents' demand for HPV vaccination by eliciting their willingness-to-pay for their adolescent daughters to be vaccinated against HPV and to examine the determinants of demand for HPV vaccination in China.

METHODS

A contingent valuation survey was conducted across three cities in Shandong Province in eastern China. We selected 11 junior middle schools with different socioeconomic features and randomly selected 6 classes in each school, and questionnaires were distributed to all girls aged 12-16 in the 66 classes for their parents to complete. A payment card approach was used to elicit parental willingness-to-pay for HPV vaccination for their daughters. We also collected a wide array of socioeconomic and psychological variables and interval regressions were applied to examine the determinants of parental willingness-to-pay.

RESULTS

A total of 1074 eligible parents who completed valid questions were included in analyses. Over 85% of parents believed HPV vaccines were, in general, necessary and beneficiary. However, only around 10% believed that their daughters would be infected by HPV. About 8% of parents would not accept HPV vaccine even if the vaccine were free mainly due to concerns about the potential side effects and vaccine safety and quality issues, and 27.37% would only accept the vaccine if it were free. The median willingness-to-pay was 300 CNY (42 USD). Several factors were positively correlated with higher willingness-to-pay: income, urban residence (relative to rural residence), mothers (relative to fathers), parents' beliefs about vaccine benefits, whether they should make decisions for their daughters, and whether their daughters would be susceptible to HPV. Though education-level was not significantly correlated with willingness-to-pay in the main regressions, a subgroup analysis revealed interesting dynamics in the relation between education and willingness-to-pay across different income-levels.

CONCLUSIONS

There is a large gap between parents' willingness-to-pay and the market price of HPV vaccine for girls in China. Parents generally believed the HPV vaccines were beneficial and necessary but when asked for their daughters, most parents did not believe their daughters would be infected by HPV despite the high prevalence in China. Future focus should be on ensuring the provision of accurate health information about HPV prevalence, vaccine quality, and safety to promote vaccine uptake, and promotional efforts tailored to different income groups might yield better effects. Government involvement in negotiating more widely acceptable and affordable prices or subsidising may be necessary for protecting high-risk population groups.

Medication safety perceptions in China: Media exposure, healthcare experiences, and trusted information sources

OBJECTIVE

Amid ongoing medication safety concerns in China and limited research on public perceptions, this study investigates the correlations between media exposure, healthcare experiences, and individuals' perceptions of medication safety. It also examines individuals' reliance on information sources during safety crises.

METHODS

A multistage stratified random sampling was employed with the gross sample containing 3090 Chinese adults aged 18-60 years. Data were analyzed using multiple linear regression.

RESULTS

Social media exposure was found to negatively correlate with perceptions of current medication safety and its perceived improvement, while exposure to television and print media showed positive correlations. Positive healthcare experiences were associated with improved medication safety perceptions. Among various information sources, healthcare professionals were deemed most trustworthy during medication safety incidents.

CONCLUSIONS

Media exposure and personal healthcare experiences significantly shape individuals' perceptions of medication safety in China, with healthcare professionals playing a crucial role in this context. Practiceimplications: Effective health crisis communication in China needs to be multifaceted, integrating traditional media and social media platforms to disseminate accurate information broadly. Additionally, healthcare professionals should be actively involved in crisis communication. Their role as trusted sources can be leveraged to clarify misconceptions, and reassure the public during medication safety incidents.

Trust in scientists on COVID-19 vaccine hesitancy and vaccine intention in China and the US

When we recognize various factors which influence vaccine willingness, it is unclear whether these factors work the same in different countries. This study explored how trust in scientists was related to COVID-19 vaccine hesitancies and vaccine willingness in China and the U.S. We attempted to understand the extent to which the perceived trustworthiness of scientists would predict vaccine hesitancies and intention to get vaccinated differently in these two countries. An online survey with participants in China (N = 391) and in the U.S. (N = 363) was conducted. Participants were asked about their view of scientists' competence, benevolence, and integrity as dimensions of trustworthiness, three types of vaccine hesitancies, as well as their willingness to get vaccinated. The results showed that trust in scientists was negatively related to individual vaccine hesitancy in both China and the U.S., and trust was negatively associated with the level of contextual hesitancy and vaccine-specific hesitancy in the U.S. Higher trust in scientists was also associated with the willingness to get vaccines in the U.S., rather than in China. Results yielded differences in China and the U.S. in how trust in scientists and vaccine hesitancies predicted individuals' willingness to get vaccinated.

Investigating Media Coverage and Public Perceptions of the HPV Vaccine in China - A Content Analysis of Weibo Posts

Human papillomavirus (HPV) is one of the most common sexually transmitted infections worldwide. The HPV vaccination has been widely advocated around the world since the vaccine is beneficial in avoiding diseases, including some sexually transmitted diseases, brought on by HPV infections. For most Chinese, the HPV vaccine is still a relatively new concept, having only been made available to the general public in 2016. Despite the vaccine's increased prominence, there is still a lack of investigation about how the public is influencing the conversation about HPV vaccines and the public's perception of this vaccine. With the theoretical construct of the Health Belief Model, this study conducts both quantitative and qualitative content analysis to investigate the existing media narratives around HPV vaccines in China and the changes in public opinion by looking at users' contributions on Weibo, one of China's most popular social networking sites. It was found that different groups of Weibo users had contributed to diverse narratives surrounding HPV vaccination. Though the public awareness of HPV vaccination had been improved along with increasingly active communication practices and enhanced public health services, public knowledge about HPV remains inadequate. Therefore, to facilitate the popularisation of HPV related knowledge, more effort should be invested in tailoring and disseminating messages that communicate responsive and comprehensive HPV related information.

Media Data and Vaccine Hesitancy: Scoping Review

Background

Media studies are important for vaccine hesitancy research, as they analyze how the media shapes risk perceptions and vaccine uptake. Despite the growth in studies in this field owing to advances in computing and language processing and an expanding social media landscape, no study has consolidated the methodological approaches used to study vaccine hesitancy. Synthesizing this information can better structure and set a precedent for this growing subfield of digital epidemiology.

Objective

This review aimed to identify and illustrate the media platforms and methods used to study vaccine hesitancy and how they build or contribute to the study of the media's influence on vaccine hesitancy and public health.

Methods

This study followed the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) guidelines. A search was conducted on PubMed and Scopus for any studies that used media data (social media or traditional media), had an outcome related to vaccine sentiment (opinion, uptake, hesitancy, acceptance, or stance), were written in English, and were published after 2010. Studies were screened by only 1 reviewer and extracted for media platform, analysis method, the theoretical models used, and outcomes.

Results

In total, 125 studies were included, of which 71 (56.8%) used traditional research methods and 54 (43.2%) used computational methods. Of the traditional methods, most used content analysis (43/71, 61%) and sentiment analysis (21/71, 30%) to analyze the texts. The most common platforms were newspapers, print media, and web-based news. The computational methods mostly used sentiment analysis (31/54, 57%), topic modeling (18/54, 33%), and network analysis (17/54, 31%). Fewer studies used projections (2/54, 4%) and feature extraction (1/54, 2%). The most common platforms were Twitter and Facebook. Theoretically, most studies were weak. The following five major categories of studies arose: antivaccination themes centered on the distrust of institutions, civil liberties, misinformation, conspiracy theories, and vaccine-specific concerns; provaccination themes centered on ensuring vaccine safety using scientific literature; framing being important and health professionals and personal stories having the largest impact on shaping vaccine opinion; the coverage of vaccination-related data mostly identifying negative vaccine content and revealing deeply fractured vaccine communities and echo chambers; and the public reacting to and focusing on certain signals-in particular cases, deaths, and scandals-which suggests a more volatile period for the spread of information.

Conclusions

The heterogeneity in the use of media to study vaccines can be better consolidated through theoretical grounding. Areas of suggested research include understanding how trust in institutions is associated with vaccine uptake, how misinformation and information signaling influence vaccine uptake, and the evaluation of government communications on vaccine rollouts and vaccine-related events. The review ends with a statement that media data analyses, though groundbreaking in approach, should supplement-not supplant-current practices in public health research.

Indonesian nursing students' intention to accept COVID-19 vaccines: an online, multicentre survey

BACKGROUND

The determinants of intention to accept the COVID-19 vaccine and associated factors among nursing students during this pandemic need to be identified.

AIMS

The study assessed nursing students' attitudes to vaccination, health engagement and trust in government, as well as their intention to have a COVID-19 vaccination.

METHODS

A cross-sectional study was carried out among nursing students in three provinces of Java, Indonesia, from December 2020 to February 2021. Convenience sampling was used to gather primary data from 640 participants through a structured online survey. Multiple linear regression was used to analyse the results.

FINDINGS

All items of vaccine attitude and health engagement as well as trust in government were positive predictors of vaccine acceptance after adjusting for confounding factors.

CONCLUSION

Nursing students were more likely to accept vaccination if they had a positive attitude to vaccination, high levels of health engagement and trust in the government regarding tackling the COVID-19 pandemic.

Analysis of the causes of inferiority feelings based on social media data with Word2Vec

Feelings of inferiority are complex emotions that usually indicate perceived weakness and helplessness. A lack of timely and effective interventions may bring serious consequences to individuals with inferiority feelings. Due to privacy concerns, those people often hesitate to seek face-to-face help, but they usually spontaneously share their feelings on social media, which makes social media a good resource for ample inferiority-related data. We randomly selected a sample of posts indicating inferiority feelings to explore the causes of inferiority. Through language analysis and natural language processing, we constructed a Word2Vec model of inferiority based on social media data and applied it to the cause analysis of inferiority feelings. The main causes of inferiority feelings are personal experience, social interaction, love relationship, etc. People feeling inferior about their personal experiences usually are largely influenced by their ways of thinking and life attitudes. Social and emotional factors overlap somewhat in the development of inferiority. In love relationships, males are more prone to inferiority feeling than females. These findings will help relevant institutions and organizations better understand people with inferiority feelings and facilitate the development of targeted treatment for those with potential self-esteem problems.

Dynamic assessment of the COVID-19 vaccine acceptance leveraging social media data

Vaccination is the most effective way to provide long-lasting immunity against viral infection; thus, rapid assessment of vaccine acceptance is a pressing challenge for health authorities. Prior studies have applied survey techniques to investigate vaccine acceptance, but these may be slow and expensive. This study investigates 29 million vaccine-related tweets from August 8, 2020 to April 19, 2021 and proposes a social media-based approach that derives a vaccine acceptance index (VAI) to quantify Twitter users’ opinions on COVID-19 vaccination. This index is calculated based on opinion classifications identified with the aid of natural language processing techniques and provides a quantitative metric to indicate the level of vaccine acceptance across different geographic scales in the U.S. The VAI is easily calculated from the number of positive and negative Tweets posted by a specific users and groups of users, it can be compiled for regions such a counties or states to provide geospatial information, and it can be tracked over time to assess changes in vaccine acceptance as related to trends in the media and politics. At the national level, it showed that the VAI moved from negative to positive in 2020 and maintained steady after January 2021. Through exploratory analysis of state- and county-level data, reliable assessments of VAI against subsequent vaccination rates could be made for counties with at least 30 users. The paper discusses information characteristics that enable consistent estimation of VAI. The findings support the use of social media to understand opinions and to offer a timely and cost-effective way to assess vaccine acceptance.

Acceptability of and barriers to human papillomavirus vaccination in China: A systematic review of the Chinese and English scientific literature

INTRODUCTION

Widespread adoption of the human papillomavirus (HPV) vaccine will require population acceptance and tailoring of immunisation services to community needs and preferences. We examined peer-reviewed publications on the acceptability of and barriers to the HPV vaccine across China.

METHODS

We searched English (MEDLINE, Embase, and Web of Science) and Chinese (CNKI, VIP, Wanfang data) databases between 1 January 2006 and 31 December 2017. We adopted a narrative approach for data synthesis.

RESULTS

We identified 73 studies. The overall median acceptability of HPV vaccine was 71.8% (Q1-Q3: 58.6%-81%). Low levels of acceptability (<40%) of HPV vaccine were found in eastern regions of China. The largest differences of acceptability were observed between rural western regions (all >90%) and urban eastern regions (all <35%). Despite these regional variations, common barriers to HPV vaccine acceptance were concerns about vaccine safety, uncertainty over vaccine effectiveness, low perceived risk of cervical cancer and the price of the vaccine. The level of willingness to pay for the HPV vaccine (over 153 US dollars) was very low (<7%).

CONCLUSION

The acceptability of and attitudes towards HPV vaccine vary by regions and populations across China. HPV vaccination programmes will need to tailor service delivery as well as information materials to take account of regional concerns.

The moderating effects of entertainers on public engagement through government activities in social media during the COVID-19

Following the onset of COVID-19 pandemic, increasing the degree of public engagement is a crucial task for governments. This study investigated the moderating effects of entertainers on public engagement through government activities during COVID-19 pandemic. The government activities were publicized through the government's social media posts. The results showed a significant positive relationship between participation of entertainers and degree of public engagement through social media. Our findings indicated that inviting entertainers to participate could improve the effects of publicity and ease the emotional tension and anxiety among the public during a crisis. However, more attention should be paid to the choice of entertainers to maintain the legality and seriousness of government activities. These findings could help the government effectively communicate prevention policies and disseminate crisis information to the public, regardless of where they were physically located.

Acceptance of a COVID-19 Vaccine Before it is Available in China During the Pandemic

Objectives: China was believed to be the country with the world’s highest acceptance rate of the COVID-19 vaccine following several investigations. This study aims to explore the Chinese acceptance of a COVID-19 vaccine before it is made available, including its determinants.

Methods: A cross-national online survey was conducted covering all 31 provinces of mainland China. The survey consists of the demographic variables, acceptance of a self-paid COVID-19 vaccine as the dependent variable, and the 3Cs factors (i.e., confidence, convenience, and complacency) as the independent variables.

Results: Among the 1,532 participants, 57.9% accepted to get a self-paid COVID-19 vaccine. COVID-19 vaccine acceptors were more likely to be concerned about the effectiveness of the vaccines, believe that they were at risk of COVID-19 infection, have a high perceived susceptibility of COVID-19, and trust in the health care system.

Conclusion: Findings indicate that the critical task in the early stage of the COVID-19 vaccine development in China is to increase the tolerance to some intuitive concerns about the vaccines, put more emphasis on the communication of the saliency of the disease threats, and effectively translate people’s trust in the government into vaccine acceptance.

Portrayals of 2v, 4v and 9vHPV vaccines on Chinese social media: a content analysis of hot posts on Sina Weibo

Rather than receive the effective 2vHPV vaccines that are readily available in China, Chinese women usually wait to receive 4v and 9vHPV vaccines, which are difficult to acquire. This means that Chinese women miss the opportunity for optimal protection from cervical cancer. As social media platforms are the main channel by which Chinese women learn about HPV vaccines, this study aimed to explore how HPV vaccines are described on social media, and in particular how they discuss or distinguish 2 v, 4 v and 9vHPV vaccines. The Octopus Web crawler tool was used to capture hot Weibo posts from 2013-2021, and 1,164 valid data were obtained. Results suggested that there are very few posts with great influence on Weibo about HPV vaccines among 9 years and much of them are created by "lay people." HPV-related topics lacked persistent popularity, comprised highly repetitive content and the spread of information was geographically diverse. There were significant differences in the media descriptions of different kinds of HPV vaccines. Price was mentioned more often in the descriptions of 2vHPV vaccines, whereas appointments were referred to most often in the descriptions of 9vHPV vaccines. There was little media attention paid to the safety and effectiveness of HPV vaccines. Chinese media should develop better collaborations with public health professionals, pay more attention to the originality of their news coverage of HPV vaccines and strive to promote HPV vaccination. Such collaboration will help news media to better understand the key points of HPV information that need to be disseminated.

The impact of negative emotional reactions on parental vaccine hesitancy after the 2018 vaccine event in China: A cross-sectional survey

Vaccination programs are cost-effective for preventing communicable diseases, yet vaccine events caused vaccine crises among parents nationwide, which has created challenges for current and future vaccination programs. This study aimed to investigate parents' emotional reactions (i.e., anger and anxiety) toward the 2018 vaccine event in China and explore the associations between parental emotional reactions and vaccine decision-making. A cross-sectional survey was conducted among 1,135 parents in 2018. Five-point Likert scales were provided for respondents to rank their anger and anxiety toward the event, and their vaccine-related trust and intentions before and after the event. Multiple logistic regression analyses were employed to explore the associations. Regarding the vaccine event, 576 (50.8%) and 402 (35.4%) respondents felt very angry and angry, and 310 (27.4%) and 516 (45.5%) respondents felt very anxious and anxious, respectively. Altogether, 797 (70.3%) respondents reported a lower trust in domestically produced vaccines after the event, and 704 (62.3%) respondents reported declines in intention to choose domestically produced vaccines for their children. Multiple logistic regression analyses revealed that anxiety was a predictor of lower trust and intention after the event (p < .001), anger was a predictor of lower trust (p = .005), and both were risk factors for declines in trust and intention (p < .01). This study confirmed that negative emotional reactions toward a vaccine event were important contributors for parental vaccine decisions. Health authorities and facilities are encouraged to act in a timely manner to reduce the public's negative emotions by providing rapid crisis responses.

Behavioural intention of receiving COVID-19 vaccination, social media exposures and peer discussions in China

The study aimed to investigate behavioural intentions to receive free and self-paid COVID-19 vaccinations (BICV-F and BICV-SP) among Chinese university students if the vaccine was 80% effective with rare mild side effects, to examine their associations with social media exposures and peer discussions regarding COVID-19 vaccination, and to explore the mediational role of perceived information sufficiency about COVID-19 vaccination. An online anonymous survey (N = 6922) was conducted in November 2020 in five Chinese provinces. Logistic regression and path analysis were adopted. The prevalence of BICV-F and BICV-SP were 78.1% and 57.7%. BICV-F was positively associated with the frequencies of passive social media exposure (adjusted odds ratio (AOR) = 1.32, P < 0.001), active social media interaction (AOR = 1.13, P < 0.001) and peer discussions (AOR = 1.17, P < 0.001). Indirect effects of the three factors on BICV-F via perceived information sufficiency were all significant (P < 0.001). The direct effect of active social media interaction on BICV-F was significantly negative (P < 0.001). Similar associations/mediations were observed for BICV-SP. The COVID-19 vaccination intention of Chinese university students needs improvement. Boosting social media exposures and peer discussions may raise students' perceived information sufficiency and subsequently increase their vaccination intention. Considering the potential negative effect of active social media interaction, caution is needed when using social media to promote COVID-19 vaccination.

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.

Characterization of Vaccine Tweets During the Early Stage of the COVID-19 Outbreak in the United States: Topic Modeling Analysis

BACKGROUND

During the early stages of the COVID-19 pandemic, developing safe and effective coronavirus vaccines was considered critical to arresting the spread of the disease. News and social media discussions have extensively covered the issue of coronavirus vaccines, with a mixture of vaccine advocacies, concerns, and oppositions.

OBJECTIVE

This study aimed to uncover the emerging themes in Twitter users' perceptions and attitudes toward vaccines during the early stages of the COVID-19 outbreak.

METHODS

This study employed topic modeling to analyze tweets related to coronavirus vaccines at the start of the COVID-19 outbreak in the United States (February 21 to March 20, 2020). We created a predefined query (eg, "COVID" AND "vaccine") to extract the tweet text and metadata (number of followers of the Twitter account and engagement metrics based on likes, comments, and retweeting) from the Meltwater database. After preprocessing the data, we tested Latent Dirichlet Allocation models to identify topics associated with these tweets. The model specifying 20 topics provided the best overall coherence, and each topic was interpreted based on its top associated terms.

RESULTS

In total, we analyzed 100,209 tweets containing keywords related to coronavirus and vaccines. The 20 topics were further collapsed based on shared similarities, thereby generating 7 major themes. Our analysis characterized 26.3% (26,234/100,209) of the tweets as News Related to Coronavirus and Vaccine Development, 25.4% (25,425/100,209) as General Discussion and Seeking of Information on Coronavirus, 12.9% (12,882/100,209) as Financial Concerns, 12.7% (12,696/100,209) as Venting Negative Emotions, 9.9% (9908/100,209) as Prayers and Calls for Positivity, 8.1% (8155/100,209) as Efficacy of Vaccine and Treatment, and 4.9% (4909/100,209) as Conspiracies about Coronavirus and Its Vaccines. Different themes demonstrated some changes over time, mostly in close association with news or events related to vaccine developments. Twitter users who discussed conspiracy theories, the efficacy of vaccines and treatments, and financial concerns had more followers than those focused on other vaccine themes. The engagement level-the extent to which a tweet being retweeted, quoted, liked, or replied by other users-was similar among different themes, but tweets venting negative emotions yielded the lowest engagement.

CONCLUSIONS

This study enriches our understanding of public concerns over new vaccines or vaccine development at early stages of the outbreak, bearing implications for influencing vaccine attitudes and guiding public health efforts to cope with infectious disease outbreaks in the future. This study concluded that public concerns centered on general policy issues related to coronavirus vaccines and that the discussions were considerably mixed with political views when vaccines were not made available. Only a small proportion of tweets focused on conspiracy theories, but these tweets demonstrated high engagement levels and were often contributed by Twitter users with more influence.

Characterizing News Report of the Substandard Vaccine Case of Changchun Changsheng in China: A Text Mining Approach

Background: The substandard vaccine case of that broke out in July 2018 in China triggered an outburst of news reports both domestically and aboard. Distilling the abundant textual information is helpful for a better understanding of the character during this public event. Methods: We collected the texts of 2211 news reports from 83 mainstream media outlets in China between 15 July and 25 August 2018, and used a structural topic model (STM) to identify the major topics and features that emerged. We also used dictionary-based sentiment analysis to uncover the sentiments expressed by the topics as well as their temporal variations. Results: The main topics of the news report fell into six major categories, including: (1) Media Investigation, (2) Response from the Top Authority, (3) Government Action, (4) Knowledge Dissemination, (5) Finance Related and (6) Commentary. The topic prevalence shifted during different stages of the events, illustrating the actions by the government. Sentiments generally spanned from negative to positive, but varied according to different topics. Conclusion: The characteristics of news reports on vaccines are shaped by various topics at different stages. The inner dynamics of the topic and its alterations are driven by the interaction between social sentiment and governmental intervention.

Understanding the perceptions of Chinese women of the commercially available domestic and imported HPV vaccine: A semantic network analysis

BACKGROUND

A domestic human papillomavirus (HPV) vaccine, Cecolin, that protects against HPV strains 16 and 18 was introduced to the Chinese market at a relatively low price in May 2020.This study has explored Chinese women's perceptions of both domestic and imported HPV vaccines, which differ in price and valency.

METHODS

Sentiment analysis and semantic network analyses were performed based on a sample of 45,729 domestic HPV vaccine-related posts from females on the Sina Weibo between April 17 and May 2, 2020. The geographic distribution was also analyzed based on the users' locations, which were retrieved from the database.

RESULTS

Most of the posts were positive and neutral (85%), although 15% were negative (e.g., expressions of anger, sadness, fear and disgust). Semantic analyses of the negative posts revealed that Chinese women generally had positive attitudes towards the HPV vaccine and were willing to be vaccinated. However, obvious geographical variations were identified. Women who lived in economically developed areas expressed a stronger desire to obtain imported quadrivalent or nonavalent vaccines due to concerns regarding effectiveness and quality. The women expressed disgust and anger mainly regarding difficulties in making an appointment, age restrictions for the nonavalent vaccine and gender restrictions. However, the population targeted by the domestic vaccine, namely women who lived in economically undeveloped areas and had relatively low incomes, had a low awareness of the HPV vaccine.

CONCLUSION

Government should provide programs, which educate females that bivalent HPV vaccine can offer protection against the majority of high-risk HPV types. Increasing awareness of the domestic vaccine among the population in economically undeveloped areas and provision of free domestic bivalent HPV vaccination/screening for low-income high-risk women would help to prevent cervical carcinoma. This issue also depends on rebuilding trust and repairing damage to the relationship between government/domestic vaccine manufacturers and the public.