The Role of Influential Actors in Fostering the Polarized COVID-19 Vaccine Discourse on Twitter: Mixed Methods of Machine Learning and Inductive Coding

The Costs of Polarizing a Pandemic: Antecedents, Consequences, and Lessons

Polarization has been rising in the United States of America for the past few decades and now poses a significant-and growing-public-health risk. One of the signature features of the American response to the COVID-19 pandemic has been the degree to which perceptions of risk and willingness to follow public-health recommendations have been politically polarized. Although COVID-19 has proven more lethal than any war or public-health crisis in American history, the deadly consequences of the pandemic were exacerbated by polarization. We review research detailing how every phase of the COVID-19 pandemic has been polarized, including judgments of risk, spatial distancing, mask wearing, and vaccination. We describe the role of political ideology, partisan identity, leadership, misinformation, and mass communication in this public-health crisis. We then assess the overall impact of polarization on infections, illness, and mortality during the pandemic; offer a psychological analysis of key policy questions; and identify a set of future research questions for scholars and policy experts. Our analysis suggests that the catastrophic death toll in the United States was largely preventable and due, in large part, to the polarization of the pandemic. Finally, we discuss implications for public policy to help avoid the same deadly mistakes in future public-health crises.

Child and adolescent COVID-19 vaccination coverage by educational setting, United States

OBJECTIVES

The COVID-19 pandemic changed the setting of education for many children in the U.S. Understanding COVID-19 vaccination coverage by educational setting is important for developing targeted messages, increasing parents' confidence in COVID-19 vaccines, and protecting all children from severe effects of COVID-19 infection.

STUDY DESIGN/METHODS

Using data from the Household Pulse Survey (n = 25,173) collected from December 9-19, 2022, January 4-16, 2023, and February 1-13, 2023, this study assessed factors associated with COVID-19 vaccination and reasons for non-vaccination among school-aged children 5-11 and adolescents 12-17 by educational setting.

RESULTS

Among children 5-11 years, COVID-19 vaccination coverage was higher among those who received in-person instruction (53.7%) compared to those who were homeschooled (32.5%). Furthermore, among adolescents 12-17 years, COVID-19 vaccination coverage was higher among those who received in-person instruction (73.5%) or virtual/online instruction (70.1%) compared to those who were homeschooled (51.0%). Children and adolescents were more likely to be vaccinated if the parental respondent had been vaccinated compared to those who had not. Among children and adolescents who were homeschooled, main reasons for non-vaccination were concern about side effects (45.4-51.6%), lack of trust in COVID-19 vaccines (45.0-50.9%), and lack of trust in the government (32.7-39.2%).

CONCLUSIONS

Children and adolescents who were home-schooled during the pandemic had lower vaccination coverage than those who attended school in person, and adolescents who were home-schooled had lower vaccination coverage than those who received virtual instruction. Based on the reasons for non-vaccination identified in this study, increasing parental confidence in vaccines, and reducing barriers to access are important for supporting COVID-19 vaccination for school-age children.

How perceived coercion polarizes unvaccinated people: The mediating role of conspiracy beliefs

During the COVID-19 pandemic, different policies were implemented to increase vaccination uptake. Meanwhile, conspiracy theories spread widely, and vaccinated versus unvaccinated people increasingly polarized against each other. This study examined the associations between perceived vaccination coercion, conspiracy beliefs and polarization. We tested the relationship of vaccination status with perceived vaccination coercion, conspiracy beliefs, and polarization, with a total sample size of N = 1202 (n = 400 in China, n = 401 in the US, and n = 401 in the UK), among them n = 603 were vaccinated and n = 599 were unvaccinated. As pre-registered, unvaccinated people perceived more vaccination coercion and endorsed more conspiracy theories. Conspiracy mentality was positively related to perceived coercion. Contrary to our hypotheses, vaccinated people were more polarized toward unvaccinated people than vice versa. Finally, conspiracy beliefs mediated the link between perceived coercion and polarization among unvaccinated people.

Perceived experts are prevalent and influential within an antivaccine community on Twitter

Perceived experts (i.e. medical professionals and biomedical scientists) are trusted sources of medical information who are especially effective at encouraging vaccine uptake. The role of perceived experts acting as potential antivaccine influencers has not been characterized systematically. We describe the prevalence and importance of antivaccine perceived experts by constructing a coengagement network of 7,720 accounts based on a Twitter data set containing over 4.2 million posts from April 2021. The coengagement network primarily broke into two large communities that differed in their stance toward COVID-19 vaccines, and misinformation was predominantly shared by the antivaccine community. Perceived experts had a sizable presence across the coengagement network, including within the antivaccine community where they were 9.8% of individual, English-language users. Perceived experts within the antivaccine community shared low-quality (misinformation) sources at similar rates and academic sources at higher rates compared to perceived nonexperts in that community. Perceived experts occupied important network positions as central antivaccine users and bridges between the antivaccine and provaccine communities. Using propensity score matching, we found that perceived expertise brought an influence boost, as perceived experts were significantly more likely to receive likes and retweets in both the antivaccine and provaccine communities. There was no significant difference in the magnitude of the influence boost for perceived experts between the two communities. Social media platforms, scientific communications, and biomedical organizations may focus on more systemic interventions to reduce the impact of perceived experts in spreading antivaccine misinformation.

The role and influence of perceived experts in an anti-vaccine misinformation community

The role of perceived experts (i.e., medical professionals and biomedical scientists) as potential anti-vaccine influencers has not been characterized systematically. We describe the prevalence and importance of anti-vaccine perceived experts by constructing a coengagement network based on a Twitter data set containing over 4.2 million posts from April 2021. The coengagement network primarily broke into two large communities that differed in their stance toward COVID-19 vaccines, and misinformation was predominantly shared by the anti-vaccine community. Perceived experts had a sizable presence within the anti-vaccine community and shared academic sources at higher rates compared to others in that community. Perceived experts occupied important network positions as central anti-vaccine nodes and bridges between the anti- and pro-vaccine communities. Perceived experts received significantly more engagements than other individuals within the anti- and pro-vaccine communities and there was no significant difference in the influence boost for perceived experts between the two communities. Interventions designed to reduce the impact of perceived experts who spread anti-vaccine misinformation may be warranted.

Examining the Negative Sentiments Related to Influenza Vaccination from 2017 to 2022: An Unsupervised Deep Learning Analysis of 261,613 Twitter Posts

Several countries are witnessing significant increases in influenza cases and severity. Despite the availability, effectiveness and safety of influenza vaccination, vaccination coverage remains suboptimal globally. In this study, we examined the prevailing negative sentiments related to influenza vaccination via a deep learning analysis of public Twitter posts over the past five years. We extracted original tweets containing the terms 'flu jab', '#flujab', 'flu vaccine', '#fluvaccine', 'influenza vaccine', '#influenzavaccine', 'influenza jab', or '#influenzajab', and posted in English from 1 January 2017 to 1 November 2022. We then identified tweets with negative sentiment from individuals, and this was followed by topic modelling using machine learning models and qualitative thematic analysis performed independently by the study investigators. A total of 261,613 tweets were analyzed. Topic modelling and thematic analysis produced five topics grouped under two major themes: (1) criticisms of governmental policies related to influenza vaccination and (2) misinformation related to influenza vaccination. A significant majority of the tweets were centered around perceived influenza vaccine mandates or coercion to vaccinate. Our analysis of temporal trends also showed an increase in the prevalence of negative sentiments related to influenza vaccination from the year 2020 onwards, which possibly coincides with misinformation related to COVID-19 policies and vaccination. There was a typology of misperceptions and misinformation underlying the negative sentiments related to influenza vaccination. Public health communications should be mindful of these findings.