This is an open-access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in the Journal of Medical Internet Research, is properly cited. The complete bibliographic information, a link to the original publication on https://www.jmir.org/, as well as this copyright and license information must be included.
Despite the existence of an effective vaccine, measles still threatens the health and lives of many Europeans. Notably, during the COVID-19 pandemic, measles vaccine uptake declined; as a result, after the pandemic, European countries will have to increase vaccination rates to restore the extent of vaccination coverage among the population. Because information obtained from social media are one of the main causes of vaccine hesitancy, knowledge of the nature of information pertaining to measles that is shared on social media may help create educational campaigns.
In this study, we aim to define the characteristics of European news about measles shared on social media platforms (ie, Facebook, Twitter, and Pinterest) from 2017 to 2019.
We downloaded and translated (into English) 10,305 articles on measles published in European Union countries. Using latent Dirichlet allocation, we identified main topics and estimated the sentiments expressed in these articles. Furthermore, we used linear regression to determine factors related to the number of times a given article was shared on social media.
We found that, in most European social media posts, measles is only discussed in the context of local European events. Articles containing educational information and describing world outbreaks appeared less frequently. The most common emotions identified from the study’s news data set were fear and trust. Yet, it was found that readers were more likely to share information on educational topics and the situation in Germany, Ukraine, Italy, and Samoa. A high amount of anger, joy, and sadness expressed within the text was also associated with a higher number of shares.
We identified which features of news articles were related to increased social media shares. We found that social media users prefer sharing educational news to sharing informational news. Appropriate emotional content can also increase the willingness of social media users to share an article. Effective media content that promotes measles vaccinations should contain educational or scientific information, as well as specific emotions (such as anger, joy, or sadness). Articles with this type of content may offer the best chance of disseminating vital messages to a broad social media audience.
The first measles vaccine was approved in 1963. Before the invention of this vaccine, measles caused 6 million deaths annually [
Despite the proven effectiveness of vaccination in saving millions of lives annually, some individuals have questioned the safety and long-term benefits of vaccine use. In 1998, Andrew Wakefield, a British physician and academic, published an article connecting the measles, mumps, and rubella (MMR) vaccine to autism among children [
One example of the result of the decline in measles vaccination coverage was the outbreak in Samoa. In September 2019, in Samoa, a country with a small population of 200,000, a measles outbreak led to over 5000 infections and 83 deaths [
This problem surrounding vaccination coverage has also been observed in Europe. The European Centre for Disease Prevention and Control (ECDC) data suggests that the second dose of MMR vaccine coverage is over 95% in only 5 European Union countries. This extent of coverage can ensure the immunity of the population against this disease and eliminate the chance of an outbreak [
We aim to characterize European measles news reports shared on social media platforms (ie, Facebook, Twitter, and Pinterest) during 2017 to 2019 (ie, the pre–COVID-19 period). For this purpose, we formulated the following 3 research questions: (1) What are the main topics of the articles on measles published in the European Union countries? (2) What sentiments are associated with these news articles? (3) Which features of the articles are associated with an increased number of shares on social media?
We collected articles on measles that were shared on Facebook, Twitter, or Pinterest from 28 European Union countries.
First, we translated the word “measles” into all 23 official languages of the European Union using Wiktionary [
As the next step, we obtained the full text of the articles (n=12,638) and read the content. To accomplish this task, we used a Python newspaper package (version 0.3.0) [
We automatically translated all non-English articles into English using Yandex Translate [
We used LDA [
We calculated the main emotions associated with each article using the syuzhet R package [
We considered a linear regression model to find the factors determining the number of shares of an article on social media (ie, the dependent variable). We used forward selection regression to create our model. We also used Cook distance method to identify and remove outliers [
After article selection and data processing, we had a final sample of 10,305 measles-related articles, published between January 1, 2017, and December 31, 2019, in European Union countries. The highest number of published articles retrieved was from Italy, but the articles that were the most shared ones were from the United Kingdom.
Description of collected data (N=10,305).
Country | Articles, n (%) | Shares | |
|
|
Total | Mean per article (SD) |
Austria | 200 (1.94) | 34,539 | 173 (425) |
Belgium | 250 (2.43) | 89,442 | 358 (1095) |
Bulgaria | 404 (3.92) | 23,418 | 58 (346) |
Croatia | 53 (0.51) | 8395 | 158 (281) |
Republic of Cyprus | 9 (0.09) | 250 | 28 (52) |
Czech Republic | 51 (0.49) | 78,043 | 1530 (3154) |
Denmark | 114 (1.11) | 92,603 | 812 (2274) |
Estonia | 13 (0.13) | 2546 | 196 (349) |
Finland | 119 (1.15) | 86,076 | 723 (2136) |
France | 1252 (12.15) | 633,111 | 506 (1826) |
Germany | 1132 (10.98) | 914,665 | 808 (4420) |
Greece | 697 (6.76) | 57,082 | 82 (792) |
Hungary | 116 (1.13) | 28,851 | 249 (568) |
Ireland | 167 (1.62) | 32,226 | 193 (389) |
Italy | 2025 (19.65) | 1,462,172 | 722 (2983) |
Latvia | 3 (0.03) | 927 | 309 (520) |
Lithuania | 1 (0.01) | 156 | 156 (0) |
Luxembourg | 20 (0.19) | 2609 | 130 (212) |
Malta | 0 (0) | 0 | N/Aa |
Netherlands | 313 (3.04) | 68,705 | 220 (607) |
Poland | 216 (2.10) | 46,658 | 216 (1042) |
Portugal | 964 (9.35) | 200,812 | 208 (1116) |
Romania | 544 (5.28) | 44,363 | 82 (459) |
Slovakia | 21 (0.20) | 4300 | 205 (255) |
Slovenia | 25 (0.24) | 2450 | 98 (232) |
Spain | 664 (6.44) | 954,613 | 1438 (18,634) |
Sweden | 253 (2.46) | 86,958 | 344 (1361) |
United Kingdom | 679 (6.59) | 2,012,118 | 2963 (23,726) |
aN/A: not applicable.
We found that 13 is the best number of topics to describe all collected news articles, accounting for the perplexity and coherence values (Table S2 of
Topics, their classification, and key words.
Topic | Main words | Group classification |
Topic 1 | immune, immune_system, study, cell, system, researcher, cancer, antibody, virus, memory | Education |
Topic 2 | child, measles, hospital, Samoa, epidemic, Sweden, people, disease, campaign, patient | World |
Topic 3 | county, York, measles, city, orthodox, Jewish, disease, USA, Brooklyn, confirm | World |
Topic 4 | measles, rash, symptom, fever, infection, disease, day, infect, cough, virus | Education |
Topic 5 | vaccine, parent, autism, child, ani, polio, Wakefield, diphtheria, study, vaccinate_child | Education |
Topic 6 | MMR, GP, December, England, measles, UK, dose_MMR, jab, HSE, NHS | Europe |
Topic 7 | vaccination, school, federal, Spahn, measles_vaccination, Germany, day_care, measles, CDU, mandatory | Europe |
Topic 8 | DGS, health, confirm, directorate, measles, outbreak, age, Portugal, UK, Lisbon | Europe |
Topic 9 | hospital, measles, Italy, health, Catania, ship, vaccinate, Sicily, hospitalize, region | Europe |
Topic 10 | country, world, Europe, organization, world_health, health_organization, European, measles, increase, Ukraine | Europe |
Topic 11 | measles, Roma, CDC, health, dose, Greece, vaccine, population, diseases, Spain | Europe |
Topic 12 | France, measles, health, agency, Aquitaine, epidemic, health_France, vaccinate, Poitiers, people | Europe |
Topic 13 | obligation, dolphin, Cicciobello, decree, sport, doll, Burioni, certification, time, market | Europe |
Using these 3 clustered meta-topics, we evaluated the popularity of all topics in each country.
Distribution of topics across all countries analzyed.
We analyzed what emotions are connected to measles-related articles in Europe.
We also determined which words contributed the most to the emotion levels in our data set. For each emotion, we reviewed the 15 most popular words from our data set, as shown in
Number of words with a certain sentiment in the data set of articles analyzed.
Emotions and connected words.
Emotion | Connected words |
Fear | disease, infection, death, hospital, epidemic, risk, infectious, contagious, die, medical, fever, prevent, bear, warn, emergency |
Trust | accord, hospital, school, doctor, medical, immunization, county, system, organization, authority, recommend, ministry, continue, level, director |
Sadness | disease, death, hospital, epidemic, infectious, die, late, sick, emergency, illness, leave, mother, fatal, fall, bad |
anticipation | child, death, time, patient, epidemic, risk, public, medical, organization, result, continue, warn, start, prevention, develop |
Disgust | disease, death, epidemic, infect, infectious, contagious, rash, cough, sick, bad, ill, nose, elimination, lose, treat |
Anger | disease, death, epidemic, bear, fatal, eradicate, bad, ill, force, fear, elimination, victim, lose, treat, fight |
Joy | child, organization, ministry, baby, majority, infant, mother, childhood, achieve, safe, grow, treat, create, save, progress |
Surprise | death, epidemic, organization, warn, emergency, infant, leave, alarm, expect, catch, lose, treat, sneeze, break, vote |
Evidently, fear is connected to words describing the harmfulness of measles. Trust is associated with the words related to health care systems and protection.
We used linear regression to identify the variables related to the number of shares of an article on social media.
We discovered that readers were more likely to share information on topics 1, 4, and 5, which convey educational information. Topics 2, 7, 10, and 13 describe the situation in Samoa, Germany, Ukraine, and Italy, and these topics were also positively associated with the number of total shares. Topic 6, which describes the situation in the United Kingdom, resulted in a reduced number of shares. Topic 4, which describes the signs and symptoms of measles, had the highest impact on the average of shareability.
With regard to emotions, on average, a higher proportion of anger, joy, and sadness expressed in an article was associated with a higher number of article shares, whereas surprise in the article was associated with reduced number of shares. Moreover, articles published in countries with a higher population and a higher number of active social media users understandably received more shares on social media.
Regression results (adjusted R2=0.04852).
Variable | Beta | Standard error | ||
Constant | –1994 | 282 | –7.08 | <.001 |
Topic 1 | 1025 | 218 | 4.695 | <.001 |
Topic 2 | 711 | 127 | 5.615 | <.001 |
Topic 4 | 1833 | 145 | 12.651 | <.001 |
Topic 5 | 475 | 196 | 2.426 | .015 |
Topic 6 | –512 | 171 | –2.994 | .003 |
Topic 7 | 1024 | 122 | 8.42 | <.001 |
Topic 10 | 616 | 114 | 5.388 | <.001 |
Topic 12 | 184 | 124 | 1.487 | .14 |
Topic 13 | 375 | 181 | 2.072 | .04 |
Anger | 54 | 15 | 3.512 | <.001 |
Joy | 53 | 14 | 3.66 | <.001 |
Surprise | –50 | 20 | –2.551 | .01 |
Sadness | 38 | 13 | 2.828 | .005 |
Disgust | –24 | 15 | –1.603 | .11 |
Social media users | 22 | 4 | 5.112 | <.001 |
Population | 0.000018 | 0.000001 | 9.393 | <.001 |
a
The number of articles published from 2017 to 2019 varies across the different countries included in this study. The highest number of articles was published in Italy, which is likely because of the high number of measles cases reported in Italy. During this period, a total of 9252 measles cases were reported in Italy [
European media mostly published news about local events, reporting on almost all significant outbreaks of measles in Europe. However, several of the events received special media attention. The decision of the German government to make the measles vaccine mandatory in response to an increase in measles cases has been frequently discussed in those articles [
The theme of world news is dominated by 2 events: One is the measles outbreak in the Orthodox Jewish community in New York [
Educational themes focus mainly on 3 threads. Some articles describe the symptoms of measles, reflecting the readers’ interest in the signs, symptoms, and causes of the disease and their desire to recognize them. The second topic is related to the scientific findings on measles, including studies on the potential oncolytic activity of this virus [
In the course of human life, up to 34,000 different emotions can be distinguished [
Characteristics of basic emotions.
Emotion | Stimulus event | Behavioral reaction | Function | Opposite emotion |
Joy | Gain of a valued object | Retain or repeat | Gain resources | Sadness |
Trust | Member of the group | Groom | Mutual support | Disgust |
Fear | Threat | Escape | Safety | Anger |
Surprise | Unexpected event | Stop | Gain time to orient | Anticipation |
Sadness | Loss of a valued object | Cry | Reattach to the lost object | Joy |
Disgust | Unpalatable object | Vomit | Eject poison | Trust |
Anger | Obstacle | Attack | Destroy obstacle | Fear |
Anticipation | New territory | Map | Knowledge of territory | Surprise |
Emotions are an important part of media articles, as emotional stories attract readers’ attention [
The analyzed articles were also highly connected with
In the field of marketing, the relationship between the basic emotions in the text and its potential to go viral has often been examined. An analysis of 7000 articles published in The New York Times revealed that positive content tends to go viral more than negative content. More specifically, this study has demonstrated that sad content is less likely to go viral, whereas articles expressing anger or anxiety result in higher number of shares on social media [
We identified a few features of news articles that are associated with an increased number of shares on social media. All educational topics are positively connected with the number of shares. This shows that social media users generally prefer to share general educational news over informational ones. This finding is consistent with the results of previous research, wherein it was proved that Facebook users are more likely to share “soft” news related to children, health, and education than “hard” news related to politics or urgent occurrences [
The results also show that information on the events in Sweden, Germany, Italy, and Ukraine was shared frequently, whereas the publication of information on the situation in the United Kingdom was negatively associated with the number of social media shares. The interest in measles in Ukraine may have been generated as a result of the country having the highest number of measles cases in Europe. In 2017-2019, the number of measles cases in Ukraine was around 100,000 [
The findings of previous research analyzing what type of web-based content become viral are generally in line with our results. They indicate that articles containing positive emotions or anger are more likely to be shared [
Articles on measles shared on social media in Europe primarily report on European events, and only a small proportion of articles report on educational news or international measles-related events. The international events mainly describe outbreaks that have occurred in a small number of infected people but are interesting from an epidemiological point of view. The distribution of topics covered by the media is similar across all European Union countries.
In this study, the two main emotions expressed in the analyzed measles-related articles were fear and trust. These emotions appeared in the articles most frequently. However, these emotions were not associated with frequent sharing of articles on social media. We found that an article has a high probability to drive public discourse if it contains educational or scientific information, as well as specific emotions (ie, anger, joy, or sadness). Making media content based on these principles can facilitate the creation of effective messages against measles vaccine hesitancy. Articles that follow these principles offer the best chance of disseminating information to a broad audience on social media and influencing the mindset of the public regarding vaccines.
Supplementary tables providing details of the analyses conducted.
The European Centre for Disease Prevention and Control
latent Dirichlet allocation
measles, mumps, and rubella
None declared.