ArticleEClinicalMedicine2020
Quantitative assessment of olfactory dysfunction accurately detects asymptomatic COVID-19 carriers.
Article in EClinicalMedicine, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 31 papers, 1 of them a synthesis that pooled it.
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
31 citing papers in PubMed, 1 synthesis or guideline pooled it, 54 citations in OpenAlex.
- The D614G Virus Mutation Enhances Anosmia in COVID-19 Patients: Evidence from a Systematic Review and Meta-analysis of Studies from South Asia.ACS chemical neuroscience · 2021Pooled it
- The Unmet Need of Olfactory Testing in Inflammatory Disorders of the Upper Airways-An EAACI Position Paper.Allergy · 2026Review
- Synaptic Inhibition in the Accessory Olfactory Bulb Regulates Pheromone Location Learning and Memory.FASEB bioAdvances · 2026Article
- Mouse olfactory system acts as anemo-detector and anemo-discriminator.Science advances · 2025Article
- Review
- Alpha-synuclein pathology and Parkinson's disease-related olfactory dysfunctions: an update on preclinical models and therapeutic approaches.Mammalian genome : official journal of the International Mammalian Genome Society · 2025Review
- Optimized laser speckle-based imaging system and methods for deep tissue cerebral blood flow imaging in small rodents.Neurophotonics · 2025Article
- Odor representation and coding by the mitral/tufted cells in the olfactory bulb.Journal of Zhejiang University. Science. B · 2024Review
- Long COVID: From olfactory dysfunctions to viral Parkinsonism.World journal of otorhinolaryngology - head and neck surgery · 2024Article
- Platelet-Rich Plasma (PRP) in the Treatment of Long COVID Olfactory Disorders: A Comprehensive Review.Biomedicines · 2024Review
- Platelet-Rich Plasma for Patients with Olfactory Dysfunction: Myth or Reality? A Systematic Review.Journal of clinical medicine · 2024Review
- Perceptual learning deficits mediated by somatostatin releasing inhibitory interneurons of olfactory bulb in an early life stress mouse model.Molecular psychiatry · 2023Article
- Knockout of angiotensin converting enzyme-2 receptor leads to morphological aberrations in rodent olfactory centers and dysfunctions associated with sense of smell.Frontiers in neuroscience · 2023Article
- Persistent olfactory learning deficits during and post-COVID-19 infection.Current research in neurobiology · 2023Article
- Asymptomatic versus symptomatic SARS-CoV-2 infection: a cross-sectional seroprevalence study.Tropical medicine and health · 2022Article
- Incidence of Anosmia among Covid 19 patients in India.Indian journal of otolaryngology and head and neck surgery : official publication of the Association of Otolaryngologists of India · 2022Article
- Objective Evaluation of Olfactory and Taste Dysfunction Among COVID-19 Patients: A Cross Sectional Study from Tribal India.Indian journal of otolaryngology and head and neck surgery : official publication of the Association of Otolaryngologists of India · 2022Article
- Article
- Article
- Pathogenesis of Olfactory Disorders in COVID-19.Brain sciences · 2022Review
Corrections and comments
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Authors and funding
5 authors at 2 institutions in 1 country.
Funding
Abstract
backgroundCOVID-19 threatens the global community because a large fraction of infected people are asymptomatic, yet can effectively transmit SARS-CoV-2. Finding and isolating these silent carriers is a crucial step in confining the spread of the disease. A sudden loss of the sense of smell has been self-reported by COVID-19 patients across different countries, consistent with expression of the molecular factors mediating SARS-CoV-2 uptake into human olfactory epithelial supporting cells. However, precise quantification of olfactory loss in asymptomatic COVID-19 carriers is missing to date.
methodsTo quantify olfactory functions in asymptomatic COVID-19 patients, we designed an olfactory-action meter that determines detectability indices at different odor concentrations and an olfactory matching accuracy score using monomolecular odors. The optimization of test parameters allowed us to reliably and accurately assess olfactory deficits in a patient within 20 minutes.
findingsMeasurement of detection indices at low concentrations revealed a 50% reduction in asymptomatic COVID-19 carriers. Further, patients with better detection scores showed significantly reduced olfactory matching accuracies compared to normal healthy subjects. Our quantification of olfactory loss, considering all parameters, identified 82% of the asymptomatic SARS-CoV-2 carriers with olfactory deficits. However, on subjective evaluation, only 15% of the patients noticed a compromised ability to smell.
interpretationCompromised olfactory fitness can serve as a strong basis for identifying asymptomatic COVID-19 patients. Detailed design specifications and protocols provided here should enable the development of a sensitive, fast, and economical screening strategy that can be administered to large populations to prevent the rapid spread of COVID-19.
fundingThis work was supported by the DBT - Wellcome Trust India Alliance intermediate grant (IA/I/14/1/501,306 to N.A.) and UGC NET Fellowship (A.B.). All the funding sources played no roles in the study.
Identifiers
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.