title: The Digital Distribution of Public Health News Surrounding the Human Papillomavirus Vaccination: A Longitudinal Infodemiology Study.
abstract: BACKGROUND
  New media changes the dissemination of public health information and misinformation. During a guest appearance on the Today Show, US Representative Michele Bachmann claimed that human papillomavirus (HPV) vaccines could cause "mental retardation".
  
  
  OBJECTIVE
  The purpose of this study is to explore how new media influences the type of public health information users access, as well as the impact to these platforms after a major controversy. Specifically, this study aims to examine the similarities and differences in the dissemination of news articles related to the HPV vaccination between Google News and Twitter, as well as how the content of news changed after Michele Bachmann's controversial comment.
  
  
  METHODS
  This study used a purposive sampling to draw the first 100 news articles that appeared on Google News and the first 100 articles that appeared on Twitter from August 1-October 31, 2011. Article tone, source, topics, concerns, references, publication date, and interactive features were coded. The intercoder reliability had a total agreement of .90.
  
  
  RESULTS
  Results indicate that 44.0% of the articles (88/200) about the HPV vaccination had a positive tone, 32.5% (65/200) maintained a neutral tone, while 23.5% (47/200) presented a negative tone. Protection against diseases 82.0% (164/200), vaccine eligibility for females 75.5% (151/200), and side effects 59.0% (118/200) were the top three topics covered by these articles. Google News and Twitter articles significantly differed in article tone, source, topics, concerns covered, types of sources referenced in the article, and uses of interactive features. Most notably, topic focus changed from public health information towards political conversation after Bachmann's comment. Before the comment, the HPV vaccine news talked more often about vaccine dosing (P<.001), duration (P=.005), vaccine eligibility for females (P=.03), and protection against diseases (P=.04) than did the later pieces. After the controversy, the news topic shifted towards politics (P=.01) and talked more about HPV vaccine eligibility for males (P=.01).
  
  
  CONCLUSIONS
  This longitudinal infodemiology study suggests that new media influences public health communication, knowledge transaction, and poses potential problems in the amount of misinformation disseminated during public health campaigns. In addition, the study calls for more research to adopt an infodemiology approach to explore relationships between online information supply and public health decisions.
authors.affiliation: West Chester University West Chester, PA United States.
authors.forename: L Meghan
authors.identifier: 0000-0002-2372-6045
authors.initials: LM
authors.lastname: Mahoney
authors.affiliation: University of Akron Akron, OH United States.
authors.forename: Tang
authors.identifier: 0000-0003-3222-4175
authors.initials: T
authors.lastname: Tang
authors.affiliation: University of New Hampshire Durham, NH United States.
authors.forename: Kai
authors.identifier: 0000-0001-8330-0559
authors.initials: K
authors.lastname: Ji
authors.affiliation: Purdue University West Fayette, IN United States.
authors.forename: Jessica
authors.identifier: 0000-0002-2437-5419
authors.initials: J
authors.lastname: Ulrich-Schad
keywords: HPV vaccination; health communication; infodemiology; infoveillance; new media; public health dissemination; social media