Communicating infectious disease prevalence through graphics: Results from an international survey

Graphics are increasingly used to represent the spread of infectious diseases (e.g., influenza, Zika, Ebola); however, the impact of using graphics to adequately inform the general population is unknown.

To examine whether three ways of visually presenting data (heat map, dot map, or picto-trendline)-all depicting the same information regarding the spread of a hypothetical outbreak of influenza-influence intent to vaccinate, risk perception, and knowledge.

Survey with participants randomized to receive a simulated news article accompanied by one of the three graphics that communicated prevalence of influenza and number of influenza-related deaths.

International online survey.

16,510 adults living in 11 countries selected using stratified random sampling based on age and gender.

After reading the article and viewing the presented graphic, participants completed a survey that measured interest in vaccination, perceived risk of contracting disease, knowledge gained, interest in additional information about the disease, and perception of the graphic.

Heat maps and picto-trendlines were evaluated more positively than dot maps. Heat maps were more effective than picto-trendlines and no different from dot maps at increasing interest in vaccination, perceived risk of contracting disease, and interest in additional information about the disease. Heat maps and picto-trendlines were more successful at conveying knowledge than dot maps. Overall, heat maps were the only graphic to be superior in every outcome.

Results are based on a hypothetical scenario.

Heat maps are a viable option to promote interest in and concern about infectious diseases.