Estimating the worldwide burden of COVID-19 related anosmia and ageusia

We investigated Google Trends (Google Inc. Mountain View, CA, US) with the search terms “anosmia” and “ageusia”, setting geographical location to “worldwide” and within a period comprising the past 5 years (i.e., between July 2017 and July 2022). The weekly Google Trends score for both terms “anosmia” and “ageusia”, thus mirroring their worldwide Web popularity, was divided into two different periods, i.e., “pre-COVID-19” (from July 2017 to February 2020) and COVID-19 (from March 2020 to July 2022). The relative volumes of Google searches for both terms were then compared between the COVID-19 and pre-COVID-19 periods with Mann-Whitney test (Analyse-it Software Ltd, Leeds, UK). Compared to the pre-COVID-19 period, the median worldwide value of the weekly Google Trends score significantly increased by 6.5-fold for anosmia and by 7.0-fold for ageusia in the COVID-19 period. A gradual decrease of web searches volumes has become apparent after the progressive worldwide spread of the SARS-CoV-2 Omicron lineages, thus reflecting a lower risk of developing these conditions in patients with SARS-CoV-2 Omicron infection. The results reveal that the volume of Web searches for both anosmia and ageusia has considerably increased after emergence of the ongoing COVID-19 pandemic.