Vaccine-related internet search activity predicts H1N1 and HPV vaccine coverage: implications for vaccine acceptance.

The Internet is a primary source for health-related information, and Internet search activity is associated with infectious disease outbreaks. The authors hypothesized that Internet search activity for vaccine-related information would predict vaccination coverage. They examined Internet search activity for H1N1 and human papilloma virus (HPV) disease and vaccine information in relation to H1N1 and HPV vaccine uptake. Google Insight for Search was used to assess the volume of Internet search queries for H1N1- and vaccine-related terms in the United States in 2009, the year of the H1N1 pandemic. Vaccine coverage data were also obtained from the Centers for Disease Control and Prevention at the state level for H1N1 vaccinations in 2009. These same measures were collected at the state level for HPV- and vaccine-related search terms in 2010 as well as HPV vaccine uptake in that year. Analyses showed that the search terms H1N1 and vaccine were correlated with H1N1 vaccine uptake; ordinal regression found the H1N1 search term was independently associated with H1N1 vaccine coverage. Similarly, the correlation between vaccine search volume and HPV coverage was significant; ordinal regression showed the search term vaccine independently predicted HPV vaccination coverage. This is among the first studies to show that Internet search activity is associated with vaccination coverage. The Internet should be exploited as an opportunity to dispel vaccine misinformation by providing accurate information to support vaccine decision making.