Media content about vaccines in the United States and Canada, 2012-2014: An analysis using data from the Vaccine Sentimeter.
A system for monitoring vaccine-related media content was previously developed and studied from an international perspective. This monitoring approach could also have value at a regional level, but it has yet to be evaluated at this scale. We examined regional patterns of vaccine-related media topics and sentiment in the US and Canada.



We extracted vaccine-relevant US and Canadian online media reports between June 2012 and October 2014 from the Vaccine Sentimeter, a HealthMap-based automated media monitoring system for news aggregators and blogs. We analyzed regional distributions of reports about vaccines, categories (i.e., topics), sentiment, and measles outbreaks.



The Vaccine Sentimeter captured 10,715 reports during the study period. Negative sentiment was highest in reports about vaccine safety (47%), Hepatitis B (19%), and Vermont (18%). Analyses of measles outbreaks revealed geographical variation in media content. For example, religious beliefs were mentioned in 27% of measles reports in Texas and 22% of British Columbia reports, but there were no references to religion in media on measles from California.



A regional analysis of online sentiment towards vaccine can provide insights that may give US and Canadian public health practitioners a deeper understanding of media influences on vaccine choices in their regions and consequently lead to more effective public health action.
McGill University, Clinical and Health Informatics, 1140 Pine Ave, Montreal, QC H3A 1A3, Canada. Electronic address: gdpwll@gmail.com.
Guido Antonio
GA
Powell
Healthmap, Computational Epidemiology Group, Children's Hospital Informatics Program, Division of Emergency Medicine, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, United States. Electronic address: kate.zinszer@mail.mcgill.ca.
Kate
K
Zinszer
McGill University, Clinical and Health Informatics, 1140 Pine Ave, Montreal, QC H3A 1A3, Canada. Electronic address: aman.verma.mtl@gmail.com.
Aman
A
Verma
Epidemico, 50 Milk Street, 20th Floor, Boston, MA 02109, United States. Electronic address: chi@epidemico.com.
Chi
C
Bahk
International Society for Infectious Diseases, United States; University of Massachusetts School of Medicine, 55 N Lake Ave, Worcester, MA 01655, United States. Electronic address: lmadoff@gmail.com.
Lawrence
L
Madoff
Healthmap, Computational Epidemiology Group, Children's Hospital Informatics Program, Division of Emergency Medicine, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, United States. Electronic address: john.brownstein@childrens.harvard.edu.
John
J
Brownstein
McGill University, Clinical and Health Informatics, 1140 Pine Ave, Montreal, QC H3A 1A3, Canada. Electronic address: david.buckeridge@mcgill.ca.
David
D
Buckeridge
D002170:Canada; D006801:Humans; D008402:Mass Media; D014481:United States; D014611:Vaccination / Q000009:adverse effects* / Q000706:statistics & numerical data*; D014612:Vaccines / Q000008:administration & dosage* / Q000276:immunology*
D014612:Vaccines
Internet Surveillance System; Measles outbreaks; Media content analyses; Vaccine hesitancy