World Pneumonia Day 2011-2016: Twitter Contents and Retweets

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Pneumonia remains a major killer of children. In 2015, 703,900 children <5 years died of lower respiratory infection globally. World Pneumonia Day (Nov 12) is an annual event advocating for pneumonia awareness. Social media (e.g. Twitter) has become part of the health communication strategy adopted by the campaign. In this study, 28,181 original tweets with hashtag #pneumonia were retrieved on Nov 21, 2016. From this Twitter corpus, 6 sub-corpora of tweets, one month before and one month after the World Pneumonia Day from 2011 to 2016 were extracted (n=998, 1409, 1036, 1369, 1221, and 688 respectively, N=6721). The underlying topics of the 6 sub-corpora were identified via unsupervised machine learning (Latent Dirichlet Allocation). Topics were then manually coded if they belonged to the themes of Raising Awareness, Promoting Intervention, and Call to Action. Given the overdispersion of retweet counts and inflated number of zeros, we used multivariable hurdle regression models to assess whether themes of Twitter contents were associated with number of retweets, controlling for hashtag count, URL presence, and the age of the tweet. We found that tweets that raised awareness, promoted interventions and called the audience to action were more likely to have retweets (adjOR=2.11, 95%CI 1.89, 2.35; 1.37, 95%CI 1.21, 1.55; 1.99, 95%CI 1.40, 2.85) and if retweeted, to have a higher retweet count by 188%, 122% and 78% respectively (adjPR=2.88, 95%CI 2.36, 2.51; 2.22, 95%CI 1.76, 2.79; 1.78, 95%CI, 1.03, 3.14). Tweets with URL links were also more likely to have retweets (adjOR=1.27, 95%CI 1.13, 1.42) and a 65% higher retweet count (adjPR=1.65, 95%CI 1.35, 2.02). We also described the Twitter topics on pneumonia and their changes over the years. In 2015 and 2016, price of vaccines occurred in the list of top 10 topics of highest number of original tweets and retweets. Our study suggests that among #pneumonia tweets, tweets raising awareness of pneumonia, promoting interventions, and calling their audience to action were more engaged by Twitter users and were likely to be retweeted than others (e.g. sharing personal experience with pneumonia).


American Society of Tropical Medicine and Hygiene Annual Meeting (ASTMH)


Baltimore, MD