Utility of Olfactory test as screening tool for COVID-19: A pilot study

Abstract

Loss of smell function (Anosmia) is reported to be associated with novel coronavirus disease 2019 (COVID-19) infection. The present study was designed to evaluate the effectiveness of an indigenously developed prototype smell test to identify/diagnose asymptomatic COVID-19 positive individuals. A panel of five different odorants belonging to Indian household with unique and mutually exclusive odor were used to develop prototype kit to test the hypothesis. The developed prototype kit was tested at 2 centers (N=49 and 34) with slight modifications. Simultaneously, the kit was also tested on 55 (N=35 and 20) healthy controls. Our results indicate that otherwise asymptomatic COVID-19 positive individuals were having quantifiable deficit in smell sensation. Interestingly, the variable sensitivity of different odorants was observed in different patients. None of the healthy controls reported difficulty in sensing any of the odorant, whereas, some of healthy controls did misidentify the odorants. Overall, the present study provides a preliminary data that loss in smell sensation for various odorants can be exploited as a quick and affordable screening test to identify infected cases among at risk individuals.

Regeneration Profiles of Olfactory Epithelium after SARS-CoV-2 Infection in Golden Syrian Hamsters

“… 10 , 11 , 22 − 24 Zonal organization is defined based on the specific ORs, but details on each specific OR and its corresponding odors have not been fully determined. 25 Decreased response to odors of mint and coconut oil was found in patients suffering anosmia due to COVID-19, 26 suggesting that receptors for these odorant molecules may be expressed in slower recovering areas of zone 1 (DT) and zone 4 (LT).…”

“…The regeneration cycle of OE is precisely regulated and maintained at 28–35 days regardless of etiology of damage. , If the OE is completely restored within this critical period, the risk of late sequelae is reduced. ,,− Zonal organization is defined based on the specific ORs, but details on each specific OR and its corresponding odors have not been fully determined . Decreased response to odors of mint and coconut oil was found in patients suffering anosmia due to COVID-19, suggesting that receptors for these odorant molecules may be expressed in slower recovering areas of zone 1 (DT) and zone 4 (LT).…”

Alteration in Status of Olfaction amongst COVID 19 Patients: A Descriptive Study in a Dedicated COVID Hospital of Eastern India

“…The above two studies show that smell impairment is lesser in Chinese population as compared to European and American population. In a study by Khare et al, 13 the percentage of COVID-19 positive individuals who were unable to either smell or identify the odorants correctly, or both, went as high as 48.9 % for single odorant and 22.5% for two odorants. The difference in identification of smell and complete inability to sense the smell was were evaluated for presence of anosmia, it was found that 11 patients (14.8%) had symptoms of anosmia while in controls that were COVID-19 negative, none had anosmia and only one subject had hyposmia.…”