title: What makes people talk about antibiotics on social media? A retrospective analysis of Twitter use.
abstract: OBJECTIVE
  Social media has reshaped individual and institutional communication. The unrestricted access to spontaneous views and opinions of society can enrich the evaluation of healthcare interventions. Antimicrobial resistance has been identified as a global threat to health requiring collaboration between clinicians and healthcare users. We sought to explore events and individuals influencing the discourse about antibiotics on Twitter.
  
  
  METHODS
  A web-based tool (www.topsy.com) was used to detect daily occurrences of the word 'antibiotic' from 24 September 2012 to 23 September 2013 in worldwide Tweets. Activity peaks (message frequency over three times that of baseline) were analysed to identify events leading to the increase.
  
  
  RESULTS
  Of 135 billion messages posted during the study period, 243000 (0.000002%) referred to 'antibiotic'. The greatest activity increases appeared after: (i) the UK Chief Medical Officer's (CMO's) declaration of antimicrobial resistance as a national risk (January 2013 and March 2013); (ii) the release of the US CDC's report on antimicrobial resistance (September 2013); and (iii) the US FDA announcement on azithromycin safety concerns (March 2013). The CMO report in March reached an estimated worldwide audience of 20 million users in a single day. However, the frequency of antibiotic Tweets returned to basal levels within 48 h of all four peaks in activity.
  
  
  CONCLUSIONS
  Institutional events can rapidly amplify antibiotic discussions on social media, but their short lifespan may hinder their public impact. Multipronged strategies may be required to prolong responses. Developing methods to refine social media monitoring to evaluate the impact and sustainability of societal engagement in the antimicrobial resistance agenda remains essential.
authors.affiliation: Medical Education Centre, North Devon District Hospital, Raleigh Park, Barnstaple, Devon EX31 4JB, UK.
authors.forename: Oliver J
authors.initials: OJ
authors.lastname: Dyar
authors.affiliation: Centre for Infection Prevention and Management, Imperial College London, Faculty of Medicine, Commonwealth Building, Du Cane Road, London W12 0NN, UK e.castro-sanchez@imperial.ac.uk.
authors.forename: Enrique
authors.initials: E
authors.lastname: Castro-Sánchez
authors.affiliation: Centre for Infection Prevention and Management, Imperial College London, Faculty of Medicine, Commonwealth Building, Du Cane Road, London W12 0NN, UK.
authors.forename: Alison H
authors.initials: AH
authors.lastname: Holmes
mesh_terms: D000900:Anti-Bacterial Agents / Q000009:adverse effects* / Q000627:therapeutic use*; D024881:Drug Resistance, Bacterial; D064420:Drug-Related Side Effects and Adverse Reactions; D006801:Humans; D061108:Social Media / Q000706:statistics & numerical data*; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents
keywords: Internet; Web 2.0; antibacterial agents