03Sensory DysfunctionCOVID-19

The impact of COVID-19

Globally, the COVID-19 pandemic has brought the loss of smell and flavor into focus.

A recently published study of 3.6 million COVID-19 patients found a high incidence of smell loss across variants1

incidence in Alpha
variant cases

incidence in Delta
variant cases

incidence in Omicron
variant cases

A published systematic review and meta-analysis of 29,349 COVID-19 patients found a2:

global pooled prevalence of flavor loss

An age and gender matched–pair case-control study in 100 patients found that3:

experienced partial or complete smell loss at
1 year

A second prospective study to evaluate 1-year outcomes in 315 COVID-19 patients found that4:

experienced partial or complete smell loss at
1 year

With over 300 million COVID-19 cases and counting in the US and EU, a conservative read of the prospective 1-year outcome study suggests there may be 40 million additional COVID-19 patients dealing with smell and flavor loss in those countries.

~20% of 2020 era and ~7% of 2021, 2022 era COVID-19 patients have long-term smell loss

References: 1. Coelho DH, Reiter ER, French E, Costanzo RM. Decreasing Incidence of Chemosensory Changes by COVID-19 Variant [published online ahead of print, 2022 May 3]. Otolaryngol Head Neck Surg. 2022;1945998221097656. doi:10.1177/01945998221097656. 2. Saniasiaya J, Islam MA, Abdullah B. Prevalence and Characteristics of Taste Disorders in Cases of COVID-19: A Meta-analysis of 29,349 Patients. Otolaryngol Head Neck Surg. 2021;165(1):33-42. doi:10.1177/0194599820981018 3. Boscolo-Rizzo P, Hummel T, Hopkins C, et al. High prevalence of long-term olfactory, gustatory, and chemesthesis dysfunction in post-COVID-19 patients: a matched case-control study with one-year follow-up using a comprehensive psychophysical evaluation. Rhinology. 2021;59(6):517-527. doi:10.4193/Rhin21.249 4. Boscolo-Rizzo P, Guida F, Polesel J, et al. Self-reported smell and taste recovery in coronavirus disease 2019 patients: a one-year prospective study. Eur Arch Otorhinolaryngol. 2022;279(1):515-520. doi:10.1007/s00405-021-06839-w