Early recovery following new onset anosmia during the COVID-19 pandemic - an observational cohort study

Claire Hopkins, Pavol Surda, Emily Whitehead, B Nirmal Kumar, Claire Hopkins, Pavol Surda, Emily Whitehead, B Nirmal Kumar

Abstract

Background: A rapidly evolving evidence suggests that smell and taste disturbance are common symptoms in COVID-19 infection. As yet there are no reports on duration and recovery rates. We set out to characterise patients reporting new onset smell and taste disturbance during the COVID-19 pandemic and report on early recovery rates.

Methods: Online Survey of patients reporting self-diagnosed new onset smell and taste disturbance during the COVID-19 pandemic, with 1 week follow-up.

Results: Three hundred eighty-two patents completed bot an initial and follow-up survey. 86.4% reported complete anosmia and a further 11.5% a very severe loss of smell at the time of completing the first survey. At follow-up 1 week later, there is already significant improvement in self-rating of severity of olfactory loss. 80.1% report lower severity scores at follow-up, 17.6% are unchanged and 1.9% are worse. 11.5% already report compete resolution at follow up, while 17.3% report persistent complete loss of smell, with reported duration being 1 to over 4 weeks. This is reflected in the overall cumulative improvement rate of 79% patients overall in the interval between surveys.

Conclusions: A review of the growing evidence base supports the likelihood that out cohort have suffered olfactory loss as part of COVID-19 infection. While early recovery rates are encouraging, long term rates will need to be further investigated and there may be an increase in patients with persistent post-viral loss as a result of the pandemic. We further call for loss of sense of smell to be formerly recognised as a marker of COVID-19 infection.

Keywords: Anosmia; COVID-19; Epidemiology; Olfactory dysfunction.

Conflict of interest statement

We have no COI to report.

Figures

Fig. 1
Fig. 1
Age distribution of respondents
Fig. 2
Fig. 2
Severity rating of loss of sense of smell at first and second survey
Fig. 3
Fig. 3
Self-reported improvement in sense of smell by time of onset, relative to completion of first survey

References

    1. Welge-Lussen A, Wolfensberger M. Olfactory disorders following upper respiratory tract infections. Adv Otorhinolaryngol. 2006;63:125–132.
    1. Brann D TT, Weinreb C, Logan D, Datta S. Non-neural exporessio of SARS-CoV-2 entry genes in the olfactory epithelium suggests mechanisms of underlying anosmai in COVID-19. ; 2020. 10.1101/2020.03.25.009084.
    1. Dube M, Le Coupanec A, Wong AHM, Rini JM, Desforges M, Talbot PJ. Axonal Transport Enables Neuron-to-Neuron Propagation of Human Coronavirus OC43. J Virol. 2018;92(18). 10.1128/JVI.00404-18.
    1. Hopkins C, Kumar N. Loss of sense of smell as a marker of COVID-19 infection. 2020.
    1. Hopkins CGS, Philpott C. Advice for patients with recent onset loss of smell during the COVID-19 pandemic. 2020.
    1. Hopkins C, Sruda P, Kumar N. Presentation of new nset anosmia during the COVID-19 pandemic. Rhinol. 2020. 10.4193/Rhin20.116.
    1. Gane SB, Kelly C, Hopkins C. Isolated sudden onset anosmia in COVID-19 infection. A novel syndrome? Rhinol. 2020. 10.4193/Rhin20.114.
    1. Mao L WM, Chen S, He Q, Chang J et al. Neurological manifestations of hospitalised patients with COVID-19 in Wuhan China: a retrospective case series. Preprint on medrxivorg. 2020.
    1. Lechien JR, Chiesa-Estomba CM, De Siati DR, Horoi M, Le Bon SD, Rodriguez A, et al. Olfactory and gustatory dysfunctions as a clinical presentation of mild-to-moderate forms of the coronavirus disease (COVID-19): a multicenter European study. Eur Arch Otorhinolaryngol. 2020.
    1. Kaye R CC, Kazahaya K, Brereton J et al. COVID-19 anosmia reporting tool: initial findings. Accepted preprint for Oto-HNS. 2020.
    1. Giacomelli A PL, Conti F, Bernacchia D, Siano M et al. Self-reported olfactory and taste disorders in SARS-CoV-2 patients: a cross-sectional study Clinical Infectious Diseases 2020, preprint 10.1093/cid/ciaa330.
    1. Menni C VA, Freydin M, Ganesh S et al. Loss of smell and taste in combination with other symptoms is a strong predictor of COVID-19 infection. MedRxiv preprint server. 2020.
    1. Yan CH, Faraji F, Prajapati DP, Boone CE, DeConde AS. Association of chemosensory dysfunction and Covid-19 in patients presenting with influenza-like symptoms. Int Forum Allergy Rhinol. 2020.
    1. Wolfel R, Corman VM, Guggemos W, Seilmaier M, Zange S, Muller MA, et al. Virological assessment of hospitalized patients with COVID-2019. Nature. 2020.
    1. Reden J, Mueller A, Mueller C, Konstantinidis I, Frasnelli J, Landis BN, et al. Recovery of olfactory function following closed head injury or infections of the upper respiratory tract. Arch Otolaryngol Head Neck Surg. 2006;132(3):265–269. doi: 10.1001/archotol.132.3.265.
    1. Duncan HJ, Seiden AM. Long-term follow-up of olfactory loss secondary to head trauma and upper respiratory tract infection. Arch Otolaryngol Head Neck Surg. 1995;121(10):1183–1187. doi: 10.1001/archotol.1995.01890100087015.
    1. Sorokowska A, Drechsler E, Karwowski M, Hummel T. Effects of olfactory training: a meta-analysis. Rhinology. 2017;55(1):17–26. doi: 10.4193/Rhin16.195.
    1. Wang W, Xu Y, Gao R, Lu R, Han K, Wu G, et al. Detection of SARS-CoV-2 in different types of clinical specimens. JAMA. 2020.

Source: PubMed

3
Sottoscrivi