The impact of news exposure on collective attention in the United States during the 2016 Zika epidemic

Abstract

In recent years, many studies have drawn attention to the important role of collective awareness and human behaviour during epidemic outbreaks. A number of modelling efforts have investigated the interaction between the disease transmission dynamics and human behaviour change mediated by news coverage and by information spreading in the population. Yet, given the scarcity of data on public awareness during an epidemic, few studies have relied on empirical data. Here, we use fine-grained, geo-referenced data from three online sources-Wikipedia, the GDELT Project and the Internet Archive-to quantify population-scale information seeking about the 2016 Zika virus epidemic in the U.S., explicitly linking such behavioural signal to epidemiological data. Geo-localized Wikipedia pageview data reveal that visiting patterns of Zika-related pages in Wikipedia were highly synchronized across the United States and largely explained by exposure to national television broadcast. Contrary to the assumption of some theoretical epidemic models, news volume and Wikipedia visiting patterns were not significantly correlated with the magnitude or the extent of the epidemic. Attention to Zika, in terms of Zika-related Wikipedia pageviews, was high at the beginning of the outbreak, when public health agencies raised an international alert and triggered media coverage, but subsequently exhibited an activity profile that suggests nonlinear dependencies and memory effects in the relation between information seeking, media pressure, and disease dynamics. This calls for a new and more general modelling framework to describe the interaction between media exposure, public awareness and disease dynamics during epidemic outbreaks.

Fig 1. Attention, media coverage and disease incidence of the Zika virus in the USA in 2016.

(A) Daily Wikipedia pageview counts of Zika related pages. B, Daily mentions of the word “Zika” in TV programs broadcasted in the U.S. extracted from the TV Internet Archive. C, Daily number of Web news mentioning “Zika” extracted from the GDELT project. D, Weekly incidence of the Zika virus reported by the CDC. Originally reported case counts were smoothed with a biweekly rolling average.

Fig 2. Correlation of public attention timelines by state.

Pearson correlation matrix of the daily Wikipedia pageviews time series of the 50 states and the District of Columbia.

Fig 3. Spatial patterns of attention.

Cities of the United States, with population higher than 40,000, where the volume of attention to ZIKV related pages was higher (panel A) or lower (panel B) than expected based on the total volume of pageviews to Wikipedia in 2016. The maps only show the 50 cities with the largest positive (panel C) or negative (panel D) difference in their pageview rankings, based on ZIKV related pages and the full Wikipedia. The labels on the maps highlight the 10 cities with highest (panel A) or lowest attention (panel B).