Global reaction to the recent outbreaks of Zika virus: Insights from a Big Data analysis

Abstract

Objective: The recent spreading of Zika virus represents an emerging global health threat. As such, it is attracting public interest worldwide, generating a great amount of related Internet searches and social media interactions. The aim of this research was to understand Zika-related digital behavior throughout the epidemic spreading and to assess its consistence with real-world epidemiological data, using a behavioral informatics and analytics approach.

Methods: In this study, the global web-interest and reaction to the recently occurred outbreaks of the Zika Virus were analyzed in terms of tweets and Google Trends (GT), Google News, YouTube, and Wikipedia search queries. These data streams were mined from 1st January 2004 to 31st October 2016, with a focus on the period November 2015-October 2016. This analysis was complemented with the use of epidemiological data. Spearman's correlation was performed to correlate all Zika-related data. Moreover, a multivariate regression was performed using Zika-related search queries as a dependent variable, and epidemiological data, number of inhabitants in 2015 and Human Development Index as predictor variables.

Results: Overall 3,864,395 tweets, 284,903 accesses to Wikipedia pages dedicated to the Zika virus were analyzed during the study period. All web-data sources showed that the main spike of researches and interactions occurred in February 2016 with a second peak in August 2016. All novel data streams-related activities increased markedly during the epidemic period with respect to pre-epidemic period when no web activity was detected. Correlations between data from all these web platforms resulted very high and statistically significant. The countries in which web searches were particularly concentrated are mainly from Central and South Americas. The majority of queries concerned the symptoms of the Zika virus, its vector of transmission, and its possible effect to babies, including microcephaly. No statistically significant correlation was found between novel data streams and global real-world epidemiological data. At country level, a correlation between the digital interest towards the Zika virus and Zika incidence rate or microcephaly cases has been detected.

Conclusions: An increasing public interest and reaction to the current Zika virus outbreak was documented by all web-data sources and a similar pattern of web reactions has been detected. The public opinion seems to be particularly worried by the alert of teratogenicity of the Zika virus. Stakeholders and health authorities could usefully exploited these internet tools for collecting the concerns of public opinion and reply to them, disseminating key information.

Fig 1

Monthly normalized data of web-searches and social network interactions related to Zika retrieved from Google Trends, Google News, Wikitrends, YouTube and Twitter from January 2004 to June 2016 (1a) and from November 2015 to October 2016 (1b).

Fig 2

Google Trends curves as Relatives Search Volumes (RSVs) for “Zika” and “Zika virus” (as “search term” or “search interest”) from January 2004 to June 2016 (2a) and from November 2015 to October 2016 (2b).

Fig 3

Global interest for Zika (3a) and Zika virus-related search terms (3b and 3c): internet activities from November 2015 to October 2016 according to country (the map was freely accessible and modifiable at the link https://commons.wikimedia.org/wiki/File:Carte_du_monde_vierge_(Allemagnes_s%C3%A9par%C3%A9es).svg).