
According to a study published earlier this year, a person that has lost their sense of smell from COVID-19 more than likely had a mild case of the virus.
Mild cases are defined as patients without evidence of viral pneumonia or hypoxia and often recover at home. A severe case would involve being taken to the hospital.
A person with either a moderate or severe cases are less likely to lose their sense of smell as a symptom.
A study of 2,581 patients from 18 European hospitals showed in that 85.9% of mild cases the patient lost their sense of smell. However, only 4.5% of patients with moderate cases lost their smell, and just 7% of those with severe-to-critical cases. The study was published in The Journal of Internal Medicine.
“Olfactory dysfunction is more prevalent in mild COVID-19 forms than in moderate-to-critical forms, and 95 percent of patients recover their sense of smell at six months post-infection,” professor Jerome Lechien, a lead author of the study at Paris-Saclay University in France, said in a statement.
Loss of smell reported by patients lasted an average of 21.6 days, according to the study.
21.4% of patients still suffered from a lack of smell after two months, also called anosmia. Those numbers dropped to 15.3% of patients after 60 days, and about 5% of patients after six months. The study also showed that younger patients could have a higher rate of anosmia than elderly patients.
“At the two months of follow-up, 75 percent to 85 percent of patients recovered olfaction according to subjective and objective olfactory evaluations," Lechien said. "The main hypothesis underlying the higher prevalence of anosmia in mild COVID-19 would consist of differences in the immune response to the infection in mild and moderate-to-critical patients. Future studies are needed to determine the long-term recovery rate of COVID-19 patients."