Even before the first cases of COVID-19 in Europe were announced in late January 2020, signs were already circulating on social media that something strange was going on. A new study from researchers at IMT School for Advanced Studies Lucca, published in Scientific reports, has identified traces of growing concern about pneumonia cases on posts published on Twitter in seven countries between late 2019 and early 2020. The analysis of the posts shows that the “whistleblowing” came precisely from the geographic regions where the primary outbreaks arose later.
To conduct the study, the authors first created a unique database of all messages posted on Twitter with the keyword ‘pneumonia’ in the seven most widely spoken languages of the European Union: English, German, French, Italian, Spanish, Polish and Dutch. – from December 2014 to March 1, 2020. The word “pneumonia” was chosen because the disease is the most serious condition caused by the SARS-CoV-2, and also because the 2020 flu season was milder than the previous one, so there was no reason to think it is responsible for all mentions and concerns. The researchers then made some adjustments and corrections to the messages in the database to avoid overestimating the number of tweets involving pneumonia between December 2019 and January 2020, that is, in the weeks between the World Health Organization (WHO) announcement that the first “cases of pneumonia of unknown etiology” were identified – on December 31, 2019 – and the official recognition of COVID19 as a serious communicable disease, on January 21, 2020. In particular, all tweets and retweets with links to news about the emerging virus were removed from the database to rule out mass media coverage of the emerging pandemic.
The authors’ analysis shows an increase in tweets mentioning the keyword “pneumonia” in most European countries included in the study as early as January 2020, indicating continued concern and public interest in pneumonia cases. In Italy, for example, where the first lock-down measures were introduced on February 22, 2020 to control COVID-19 infections, the increase in the number of pneumonia reports during the first weeks of 2020 differs significantly from the rate reported in the same weeks perceived. in 2019. That is, potentially hidden infection hotspots were identified several weeks before the announcement of the first local source of a COVID-19 infection (February 20, Codogno, Italy). France showed a similar pattern, while Spain, Poland and the UK witnessed a two-week delay.
The authors also geolocated more than 13,000 pneumonia-related tweets during the same period and found that they came precisely from the regions where the first cases of infections were later reported, such as the Lombardy region of Italy, Madrid, Spain and Île. de France.
Using the same procedure used for the keyword “pneumonia,” the researchers also produced a new dataset with the keyword “dry cough,” one of the other symptoms later associated with COVID-19 syndrome. Even then, they saw the same pattern, namely an abnormal and statistically significant increase in the number of mentions of the word in the weeks leading up to the wave of infections in February 2020.
“Our study complements existing evidence that social media can be a useful tool for epidemiological surveillance. They can help intercept the first signs of a new disease before it spreads unnoticed, as well as track its spread,” says Massimo. Riccaboni, Professor of Economics at IMT School, who coordinated the research.
This is especially true in a situation like the current pandemic, when the failure to signal early warning signs left many national governments blind to the unprecedented magnitude of the impending public health emergency. In a successive phase of the pandemic, monitoring social media could help public health authorities reduce the risks of a resurgence of contamination, for example by taking stricter measures of social distancing where infections seem to be increasing, or vice versa illuminate regions. These tools could also pave the way for an integrated epidemiological surveillance system managed worldwide by international health organizations.
###
The newspaper “Early Warning of COVID-19 outbreaks across Europe from social media” is available after publication at: http: // www.
Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of any press release posted on EurekAlert! by contributing institutions or for the use of information through the EurekAlert system.