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

  1. Pragyanshu Khare
  2. Atul Munish Chander
  3. Kanhaiya Agrawal
  4. Satyam Singh Jayant
  5. Soham Mukherjee
  6. Kamalendra Yadav
  7. Rahul Gupta
  8. Shakun Chaudhary
  9. Sumit Srivastava
  10. Sanuj Muralidharan
  11. Rijin Mohan
  12. Shikha Chaudhary
  13. Rimesh Pal
  14. Sandeep Bansal
  15. Kanthi Kiran Kondepudi
  16. Govardhan Dutt Puri
  17. Mahendra Bishnoi
  18. Sanjay Kumar Bhadada

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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.

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  1. ScreenIT

    SciScore for 10.1101/2020.09.03.20187294: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    Institutional Review Board StatementIRB: The study was approved by Institute Ethics committee, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh.
    Randomizationnot detected.
    BlindingFollowing first study, we modified the test to include (a) blank (water) smell and (b) change the order of each odorant in each kit and (c) test was performed in double blind form.
    Power Analysisnot detected.
    Sex as a biological variablenot detected.

    Table 2: Resources

    No key resources detected.

    Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).

    Results from LimitationRecognizer: We detected the following sentences addressing limitations in the study:
    This study has limitation to not able in acquisition of follow-up data of these anosmic/ hyposmic patients at recovery from disease, because the study was planned with a motive of commercialization rather than to study the pathophysiology of anosmia in infection. In our study, although, the COVID-19 asymptomatic patient group was not presenting symptoms associated with congestion or nasal blockage but still the traits of loss of smell were noticed in the respondents indicating the importance of mechanisms other than congestion in pathoetiology of COVID-19 associated anosmia [6, 11]. Moreover, the variable response of asymptomatic patient to the different types of odors can be attributed to the level of virus induced dysfunctions leading to neuronal damage due to COVID-19 infection which is not completely known yet but a recent study has pointed towards this [12] This type of tests if developed and validated in larger set of population will have many advantages. It will enable us do rapid and wider testing to identify at risk individuals as well localities. Also, it allows independent non-invasive self-testing facility. This test has a potential to be one of the scanning/screening tests along with temperature sensation (thermometer) at the entry points of hospitals, government and private offices, shops and other places of public dealing in order to have a safe cordon. In summary, the present study is a step forward in exploiting hyposmia and anosmia in asymptomatic COVID-19 p...

    Results from TrialIdentifier: No clinical trial numbers were referenced.

    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.

    Results from JetFighter: We did not find any issues relating to colormaps.

    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • No protocol registration statement was detected.

    About SciScore

    SciScore is an automated tool that is designed to assist expert reviewers by finding and presenting formulaic information scattered throughout a paper in a standard, easy to digest format. SciScore checks for the presence and correctness of RRIDs (research resource identifiers), and for rigor criteria such as sex and investigator blinding. For details on the theoretical underpinning of rigor criteria and the tools shown here, including references cited, please follow this link.

  2. Version published to 10.1101/2020.09.03.20187294v1 on medRxiv