Smell loss is a frequently reported symptom of COVID-19 but reports of prevalence vary from study-to-study and range from 5% to 98%. With such a wide range of estimates, it is difficult to prioritize its importance for testing and treatment.
Investigators, led by the Monell Chemical Senses Center, determined in part why the reports vary so much. They reviewed existing research to determine whether the studies that used direct measures versus self-report of smell loss could explain the range of estimates. They found that with direct measures, about 77% of COVID-19 patients had smell loss versus