Assessment of the impact of media coverage in coronavirus-related Google Trends: Infodemiology study.

BACKGROUND: The influence of media coverage in online searches may hamper the role of Google Trends (GT) for Covid-19 monitoring. OBJECTIVE: To assess whether Covid-19-related GT - particularly on ageusia and anosmia - were primarily related to media coverage or with epidemic trends. METHODS: We retrieved GT data for searches on "coronavirus", "cough", "anosmia" and "ageusia", plotting them for a period of 5 years. In addition, we analysed the trends of those queries for 17 countries throughout the year of 2020, particularly concerning rises and peaks of searches. For anosmia and ageusia, we assessed whether the respective GT correlated with Covid-19 cases and deaths both throughout 2020 and specifically before March 16, 2020 (i.e., the date when the media started reporting that those symptoms could be associated with Covid-19). RESULTS: Over the last five years, peaks of "coronavirus" GT were only observed during the Winter of 2020. Rises and peaks in "coronavirus" searches were similar in time in the 17 different assessed countries, irrespectively of their epidemic situation. In 15 of these countries, rises in "anosmia" and "ageusia" GT occurred in the same week or one week after they were identified in the media as symptoms of Covid-19. Analysing data prior to March 16, 2020, anosmia/ageusia GT were found to have variable correlation with Covid-19 cases and deaths in the different countries. CONCLUSIONS: Covid-19-related GT is more related to media coverage than with epidemic trends.