Tracking Health Related Discussions on Reddit for Public Health Applications.

We use Reddit to demonstrate social media's potential for public health applications. First, we employ a lexicon-based approach to track the prevalence of keywords indicating public interest in Ebola, electronic cigarette, influenza, and marijuana. Second, to better understand the public reactions, we use the Latent Dirichlet Allocation algorithm, to identify either the general themes or motivations for extreme changes in the volume of discussion over time. We observe that discussions related to Ebola and influenza, infectious diseases of public health interests, surged when the first case of Ebola was diagnosed and a new strain of H1N1 influenza virus was confirmed in the United States. We also observed that discussions of a controversial health topic like marijuana increased with the announcement of a major change in United States federal policy. Discussions of electronic cigarette highlighted opportunities for better health education. Lastly, we discuss the implications of our findings for utilizing Reddit data for public health applications.