Olfactory recovery following omicron variant infection: a psychophysical prospective case–control study with six-month follow up

Abstract

Objective This study aimed to evaluate the recovery of olfactory function at six months in individuals infected with the coronavirus disease 2019 omicron variant, using psychophysical tests. Methods A prospective case–control study that included severe acute respiratory syndrome coronavirus-2 patients infected in February and March 2022 was conducted. Patients underwent the Sniffin’ Sticks test within 10 days of infection and again after at least 6 months. The olfactory scores were compared with those of a control group. Results In all, 102 patients and 120 controls were enrolled in the study. At baseline, 26 patients (25.5 per cent) self-reported smell loss. The median threshold, discrimination and identification score was 33.6 (interquartile range, 12.5) for the cases and 36.5 (interquartile range, 4.38) for the controls (p < 0.001). Based on the threshold, discrimination and identification scores, 12 controls and 34 patients reported olfactory dysfunction (p < 0.001). Eighty cases underwent re-evaluation at six months; the median threshold, discrimination and identification score was 37.1 (interquartile range, 4.75) with no significant differences compared with the controls. Conclusion Six months after infection, the prevalence of olfactory dysfunction in patients did not differ significantly from the control population.

Probiotics for chronic rhinosinusitis, olfactory recovery following omicron variant infection and aural myiasis in Ancient Rome

“…Vaira et al, in this month's issue of The Journal, evaluate the recovery of olfactory function at six months in individuals infected with the Covid-19 omicron variant, compared with healthy controls, using psychophysical tests. 7 In this study, omicron variant infection was associated with a significantly lower persistent olfactory dysfunction rate than previous Covid-19 variants, and, at six months, the prevalence of olfactory dysfunction in infected patients did not differ significantly from that in the general population. It has been hypothesised that the omicron variant is less destructive to the olfactory neuroepithelium and less neuroinvasive.…”

The Prognostic Value of Olfactory Dysfunction in Patients with COVID-19: The COVIDORA Study

“…60.7% (n = 292/481) of patients reported OD in our population of patients who tested positive for SARS-CoV-2, which is consistent with the literature on OD within Western countries during the first wave of the pandemic [ 8 , 9 , 23 , 24 ], including a meta-analysis on 27,492 patients who reported an OD prevalence of 54% for European studies in their subgroup analyses by continent [ 24 ]. Even though the prevalence of smell impairment has decreased all over the world with the spread of new variants of SARS-CoV-2 [ 25 , 26 , 27 ], how can we explain such a high prevalence of this symptom during the early phase of the pandemic in Western countries [ 24 ]. If some parts of the pathophysiology of OD in COVID-19 disease remain unclear, the main underlying mechanisms are now well known.…”