On the relationship between neurocognitive measures and olfactory dysfunction in COVID-19 patients with and without anosmia.

One of the predominant symptoms of the COVID-19 virus is the complete (anosmia) or partial (hyposmia) loss of smell. Anosmia may be a critical neurocognitive symptom because there is an empirically demonstrated association of anosmia with neurodegenerative diseases like Parkinson's disease, Alzheimer's disease, etc. The present study assessed the neurocognitive disorder patterns in recovered COVID-19 patients who either self-reported anosmia or its absence. Of the 60 adult participants (n = 32 males, n = 28 females; Mage = 20.78 years, range = 18-31 years), 15 reported COVID-19 induced anosmia, 15 reported COVID-19 without anosmia, and 30 reported not having contracted COVID-19. The participants were first administered a 10-item smell test, and analysis of variance revealed significantly better scores for the control group than the other two groups. Further, there was no significant difference in smell scores between the patients who self-reported anosmia or denied it. This statistical pattern was consistent across all neuropsychological tests: short- and long-term verbal memory, digit span, Trail Making, and a self-report 46-item neurocognitive scale. Regardless of the self-report of anosmia or denial, all thirty COVID-19 patients scored significantly poorer than the control group on all of the tests and neurocognitive scale. In summary, the self-report of anosmia appears to be unreliable, and the COVID-19 patients who were found to be anosmic on the initial objective smell test demonstrated poorer neuropsychological performance than controls.

Proof-of-concept: SCENTinel 1.1 rapidly discriminates COVID-19-related olfactory disorders.

It is estimated that 20%-67% of those with COVID-19 develop olfactory disorders, depending on the SARS-CoV-2 variant. However, there is an absence of quick, population-wide olfactory tests to screen for olfactory disorders. The purpose of this study was to provide a proof-of-concept that SCENTinel 1.1, a rapid, inexpensive, population-wide olfactory test, can discriminate between anosmia (total smell loss), hyposmia (reduced sense of smell), parosmia (distorted odor perception), and phantosmia (odor sensation without a source). Participants were mailed a SCENTinel 1.1 test, which measures odor detection, intensity, identification, and pleasantness, using one of 4 possible odors. Those who completed the test (N = 287) were divided into groups based on their self-reported olfactory function: quantitative olfactory disorder only (anosmia or hyposmia, N = 135), qualitative olfactory disorder only (parosmia and/or phantosmia; N = 86), and normosmia (normal sense of smell; N = 66). SCENTinel 1.1 accurately discriminates quantitative olfactory disorders, qualitative olfactory disorders, and normosmia groups. When olfactory disorders were assessed individually, SCENTinel 1.1 discriminates between hyposmia, parosmia, and anosmia. Participants with parosmia rated common odors less pleasant than those without parosmia. We provide proof-of-concept that SCENTinel 1.1, a rapid smell test, can discriminate quantitative and qualitative olfactory disorders, and is the only direct test to rapidly discriminate parosmia.

Screening for Olfactory Dysfunction in COVID-19 Patients Using Quick Smell Identification Test.

OBJECTIVE: To determine the prevalence of OD in the confirmed case with COVID-19 among our population using quick smell identification test (Q-SIT) as screening tool. METHODS: Cross- sectional study carried out in Qatif area-Saudi Arabia among adult hospitalized patient with confirm COVID-19 during the period between May and July, 2020. All adults confirmed COVID-19 patients were interviewed for history of current disease and associated symptoms as well as performing Q-SIT. Participants who had history of olfactory dysfunction, and critical cases required ICU admission were excluded. RESULTS: The prevalence of OD among COVID-19 cases was (16.3%) in our population using Q-SIT compared to (27.4%) for self-reported symptom. Females were having higher prevalence in compare to males (30.5% and 11.1%) respectively; which was statistically significant (P < 0.001). The patients reported higher prevalence of ageusia (31.9%) with significant association with OD (P < 0.001). Q-SIT showed high positive and negative predictive value in detecting OD among patients with COVID-19 (84% and 93% respectively). CONCLUSION: Q-SIT is a useful, validated and easy to apply tool for screening OD among patients with COVID-19. Some patients presented solely with this symptom which can occurs unnoticed in COVID-19 patients, and there for required objective test for detection.

Analysis of Prevalence and Predictive Factors of Long-Lasting Olfactory and Gustatory Dysfunction in COVID-19 Patients.

BACKGROUND: Although smell and taste disorders are highly prevalent symptoms of COVID-19 infection, the predictive factors leading to long-lasting chemosensory dysfunction are still poorly understood. METHODS: 102 out of 421 (24.2%) mildly symptomatic COVID-19 patients completed a second questionnaire about the evolution of their symptoms one year after the infection using visual analog scales (VAS). A subgroup of 69 patients also underwent psychophysical evaluation of olfactory function through UPSIT. RESULTS: The prevalence of chemosensory dysfunction decreased from 82.4% to 45.1% after 12 months, with 46.1% of patients reporting a complete recovery. Patients older than 40 years (OR = 0.20; 95% CI: [0.07, 0.56]) and with a duration of loss of smell longer than four weeks saw a lower odds ratio for recovery (OR = 0.27; 95% CI: [0.10, 0.76]). In addition, 28 patients (35.9%) reported suffering from parosmia, which was associated with moderate to severe taste dysfunction at the baseline (OR = 7.80; 95% CI: [1.70, 35.8]). Among the 69 subjects who underwent the UPSIT, 57 (82.6%) presented some degree of smell dysfunction, showing a moderate correlation with self-reported VAS (r = -0.36, p = 0.0027). CONCLUSION: A clinically relevant number of subjects reported persistent chemosensory dysfunction and parosmia one year after COVID-19 infection, with a moderate correlation with psychophysical olfactory tests.

Unmasking the 'Asymptomatic' COVID-19: A Nose Question.

The new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has high infectivity, often masked by asymptomatic carriers, which allows it to spread rapidly and become a pandemic. Attempts to slow the pandemic at this stage depend on the ability to unmask asymptomatic carriers. The rapid diagnosis of active coronavirus disease 2019 (COVID-19) infection is one of the cornerstones of pandemic control, as the nasal cavity is the main gateway for SARS-CoV-2 entry and altered sense of smell is a feature of the current virus. In the present study, we therefore tested the olfactory threshold coupled with heart-lung parameters in subjects undergoing traditional molecular testing, resulting in a significantly different score between asymptomatic subjects and healthy controls. In total, 82% of asymptomatic positives showed olfactory impairment; of these, 46% had severe hyposmia and 7% had anosmia, while in the control 9% had severe hyposmia and 0% had anosmia, respectively, which agrees with heart rate, breathing rate, and blood pressure parameter variations. The olfactory test coupled with physiological parameters may help to identify asymptomatic people. In conclusion, our results suggest that most asymptomatic individuals could be unmasked by mass olfactory rapid threshold screening and then referred to traditional slower diagnostic tests.

The 8-Odorant Barcelona Olfactory Test (BOT-8): Validation of a New Test in the Spanish Population During the COVID-19 Pandemic.

BACKGROUND AND OBJECTIVE: Most smell tests are difficult to implement in daily clinical practice owing to their long duration. The aim of the present study was to develop and validate a short, easy-to-perform, and reusable smell test to be implemented during the COVID-19 pandemic. METHODS: The study population comprised 120 healthy adults and 195 patients with self-reported olfactory dysfunction (OD). The 8-Odorant Barcelona Olfactory Test (BOT-8) was used for detection, memory/recognition, and forced-choice identification. In addition, a rose threshold test was performed, and a visual analog scale was applied. The Smell Diskettes Olfaction Test (SDOT) was used for correlation in healthy volunteers, and the University of Pennsylvania Smell Identification Test (UPSIT) was used for patients with OD to establish cut-offs for anosmia and hyposmia. In order to take account of the COVID-19 pandemic, disposable cotton swabs with odorants were compared with the original test. RESULTS: In healthy persons, the mean (SD) BOT-8 score was 100% for detection, 94.5% (1.07) for memory/recognition, and 89.6% (0.86) for identification. In patients with OD, the equivalent values were 86% (32.8), 73.2% (37.9), and 77.1% (34.2), respectively. BOT-8 demonstrated good test-retest reliability, with agreement of 96.7% and a quadratic k of 0.84 (P<.001). A strong correlation was observed between BOT-8 and SDOT (r=0.67, P<.001) and UPSIT (r=0.86, P<.001). Agreement was excellent for disposable cotton swabs, with a k of 0.79 compared with the original test. The cut-off point for anosmia was ≤3 (area under the curve, 0.83; sensitivity, 0.673; specificity, 0.993). CONCLUSION: BOT-8 offers an efficient and fast method for assessment of smell threshold, detection, memory, and identification in daily clinical practice. Disposable cotton swabs with odorants proved to be useful and safe during the COVID-19 pandemic.

Proportion of New Onset of Anosmia and Its Diagnostic Significance in COVID-19.

OBJECTIVE: This study aimed to know the proportion of new-onset of anosmia and to find its diagnostic significance in coronavirus disease 2019 (COVID-19) patients attending the hospital. Study design and duration: The Indian smell test in COVID-19 by AIIMS Raipur (ISCA-R) was developed for evaluating olfaction in the Indian population. The olfactory function was assessed using the corona scale on anosmia AIIMS Raipur (COSANAr). RESULTS: Out of 256 patients, 171 were males and 85 were females. In the majority of the patients, 75 (29.29%), the COSANAr score "0" was higher on the day of admission compared to the score "3" on the day of discharge with 61 (23.82%) patients. There was no improvement in 134 (52.34%) patients with loss of smell at the time of discharge. CONCLUSION: This study is a step forward in identifying anosmia by ISCA-R at the early stages of the COVID phase. The COSANAr is affordable for the Indian population. It is noticed that most of the patients have mild hyposmia at the time of discharge and anosmia at the admission time.

Residual olfactory dysfunction in coronavirus disease 2019 patients after long term recovery.

INTRODUCTION: Hyposmia is among the most common symptoms of COVID-19 patients. Previous research has mainly described this issue at the disease's early stages. Because olfactory impairment can indicate neurological degeneration, we investigated the possibility of permanent olfactory damage by assessing hyposmia during the late recovery stage of COVID-19 patients. METHODS: Ninety-five patients were assessed with the Brief Smell Identification Test for Chinese (B-SITC) and Hyposmia Rating Scale (HRS) after 16 weeks from disease onset. Five weeks later, 41 patients were retested with B-SITC. RESULTS: At the first visit, hyposmia was identified in 26/82 (31.7%) and 22/95 (23.2%) of participants by HRS (HRS score ≤22) and B-SITC (B-SITC score <8), respectively. The rates of hyposmia in patients who performed B-SITC after 14-15 weeks, 16-17 weeks, and ≥18 weeks from disease onset were 7/25 (28%), 8/35 (23%) and 7/35 (20%), respectively, which demonstrated a trend of olfaction improvement as recovery time prolonging. Hyposmia percentages decreased from the first visit (34.1%) to the second visit (24.4%) for the 41 patients who completed 2 visits. B-SITC scores of the first-visit hyposmia participants increased significantly at the second visit (5.29 ± 2.02 to 8.29 ± 2.40; n = 14, P = 0.001). Severe cases tended to recover less than common cases. CONCLUSIONS: Hyposmia was present in up to one-third of COVID-19 patients after about 3 months from disease onset. Notable recovery of olfactory function was observed at a next 5-weeks follow-up. Clinical severity had little influence on olfactory impairment and recovery.

Diagnosis of Anosmia and Hyposmia: A Systematic Review.

BACKGROUND: Anosmia and hyposmia have many etiologies, including trauma, chronic sinusitis, neoplasms, and respiratory viral infections such as rhinovirus and SARS-CoV-2. We aimed to systematically review the literature on the diagnostic evaluation of anosmia/hyposmia. METHODS: PubMed, EMBASE, and Cochrane databases were searched for articles published since January 1990 using terms combined with Medical Subject Headings (MeSH). We included articles evaluating diagnostic modalities for anosmia, written in the English language, used original data, and had two or more patients. RESULTS: A total of 2065 unique titles were returned upon the initial search. Of these, 226 abstracts were examined, yielding 27 full-text articles meeting inclusion criteria (Level of evidence ranging from 1 to 4; most level 2). The studies included a total of 13,577 patients. The most utilized diagnostic tools were orthonasal smell tests (such as the Sniffin' Sticks and the UPSIT, along with validated abridged smell tests). Though various imaging modalities (including MRI and CT) were frequently mentioned in the workup of olfactory dysfunction, routine imaging was not used to primarily diagnose smell loss. CONCLUSION: The literature includes several studies on validity and reliability for various smell tests in diagnosing anosmia. Along with a thorough history and physical, validated orthonasal smell tests should be part of the workup of the patient with suspected olfactory dysfunction. The most widely studied modality was MRI, but criteria for the timing and sequence of imaging modalities was heterogenous.

A novel capsule-based smell test fabricated via coaxial dripping.

In this paper, we demonstrate that aromatic oil capsules, produced by dripping droplets, can offer a simple, yet effective, testing tool to aid in the diagnosis of various diseases, in which the loss of smell is a key symptom. These include chronic neurological conditions such as Parkinson's and Alzheimer's diseases, and acute respiratory infections such as that caused by COVID-19. The capsules were fabricated by concentrically dripping oil/alginate droplets, from a coaxial nozzle, into an oppositely charged ionic liquid. This fabrication technique enables full control over the capsule size, the shell thickness and the volume of the encapsulated oil. After formation, liquid capsules were left to dry and form a solid crust surrounding the oil. The prototype test consists of placing a standardized number of capsules between adhesive strips that users crush and pull apart to release the smell. In addition to the fabrication method, a simple mathematical model was developed to predict the volume of encapsulated oil within the capsule in terms of the flow rate ratio and the nozzle size. Tensile tests show that capsule strength is inversely proportional to its size owing to an increase in the shell thickness. By increasing the alginate concentration, the load required to rupture the capsule increases, to the point where capsules are too stiff to be broken by a fingertip grip. Results from a preliminary screening test, within a group of patients with Parkinson's disease, found that smells were detectable using a 'forced choice' paradigm.

Olfactory dysfunction in SARS-CoV-2 infection: Focus on odorant specificity and chronic persistence.

BACKGROUND: Smell dysfunction has been recognized as an early symptom of SARS-CoV-2 infection, often occurring before the onset of core symptoms of the respiratory tract, fever or muscle pain. In most cases, olfactory dysfunction is accompanied by reduced sense of taste, is partial (microsmia) and seems to normalize after several weeks, however, especially in cases of virus-induced complete smell loss (anosmia), there are indications of persisting deficits even 2 months after recovery from the acute disease, pointing towards the possibility of chronic or even permanent smell reduction for a significant part of the patient population. To date, we have no knowledge on the specificity of anosmia towards specific odorants or chemicals and about the longer-term timeline of its persistence or reversal. METHODS: In this longitudinal study, 70 participants from a community in Lower Austria that had been tested positive for either IgG or IgM SARS-CoV-2 titers in June 2020 and a healthy control cohort (N = 348) underwent smell testing with a 12-item Cross-Cultural Smell Identification Test (CC-SIT), based upon items from the University of Pennsylvania Smell Identification Test (UPSIT). The test was performed in October 2020, i.e. 4 months after initial diagnosis via antibody testing. Results were analyzed using statistical tests for contingency for each smell individually in order to detect whether reacquisition of smell is dependent on specific odorant types. RESULTS: For all odorants tested, except the odor "smoke", even 4 months or more after acute SARS-CoV-2 infection, participants with a positive antibody titer had a reduced sense of smell when compared to the control group. On average, while the control cohort detected a set of 12 different smells with 88.0% accuracy, the antibody-positive group detected 80.0% of tested odorants. A reduction of accuracy of detection by 9.1% in the antibody-positive cohort was detected. Recovery of the ability to smell was particularly delayed for three odorants: strawberry (encoded by the aldehyde ethylmethylphenylglycidate), lemon (encoded by citronellal, a monoterpenoid aldehyde), and soap (alkali metal salts of the fatty acids plus odorous additives) exhibit a sensitivity of detection of an infection with SARS-CoV-2 of 31.0%, 41.0% and 40.0%, respectively. CONCLUSION: Four months or more after acute infection, smell performance of SARS-CoV-2 positive patients with mild or no symptoms is not fully recovered, whereby the ability to detect certain odors (strawberry, lemon and soap) is particularly affected, suggesting the possibility that these sensitivity to these smells may not only be lagging behind but may be more permanently affected.

Persisting olfactory dysfunction improves in patients 6 months after COVID-19 disease.

BACKGROUND: Smell disorders persist in about half of the patients with other symptoms of COVID-19 disease, but the exact duration of the symptoms is yet unknown. Especially, only a few studies used validated olfactory tests for this. AIMS/OBJECTIVES: The aim of this study was to investigate how many patients with olfactory function impairment, which was detected in a validated olfactory test 3 months after COVID-19 disease, showed improvement in olfactory function after 6 months. METHODS: About 26 patients with a PCR-confirmed, former COVID-19 disease, with an impaired olfactory function after three months, were included in the study. The olfactory function was evaluated with the sniffing sticks test, the taste function with taste sprays. RESULTS: Smelling function improved in all but one patient (96%). All measured subitems, i.e. olfactory threshold, identification and discrimination of odours significantly improved. In the whole mouth taste test all patients showed normal taste function. CONCLUSIONS AND SIGNIFICANCE: 6 months after COVID-19 disease, olfactory function improves in just about all patients. Long-term measurements must investigate whether complete regeneration of the olfactory function will occur in all patients.

SCENTinel 1.0: Development of a Rapid Test to Screen for Smell Loss.

Commercially available smell tests are primarily used in research or in-depth clinical evaluations and are too costly and time-consuming for population surveillance in health emergencies like COVID-19. To address this need, we developed the SCENTinel 1.0 test, which rapidly evaluates 3 olfactory functions: detection, intensity, and identification. We tested whether self-administering the SCENTinel 1.0 test discriminates between individuals with self-reported smell loss and those with average smell ability (normosmic individuals) and provides performance comparable to the validated and standardized NIH Toolbox Odor Identification Test in normosmic individuals. Using Bayesian linear models and prognostic classification algorithms, we compared the SCENTinel 1.0 performance of a group of self-reported anosmic individuals (N = 111, 47 ± 13 years old, F = 71%) and normosmic individuals (N = 154, 47 ± 14 years old, F = 74%) as well as individuals reporting other smell disorders (such as hyposmia or parosmia; N = 42, 55 ± 10 years old, F = 67%). Ninety-four percent of normosmic individuals met our SCENTinel 1.0 accuracy criteria compared with only 10% of anosmic individuals and 64% of individuals with other smell disorders. Overall performance on SCENTinel 1.0 predicted belonging to the normosmic group better than identification or detection alone (vs. anosmic: AUC = 0.95, specificity = 0.94). Odor intensity provided the best single-feature predictor to classify normosmic individuals. Among normosmic individuals, 92% met the accuracy criteria at both SCENTinel 1.0 and the NIH Toolbox Odor Identification Test. SCENTinel 1.0 is a practical test able to discriminate individuals with smell loss and will likely be useful in many clinical situations, including COVID-19 symptom screening.

Is taste and smell impairment irreversible in COVID-19 patients?

OBJECTIVE: It is known that the COVID-19 disease, which has affected the whole world, causes symptoms, such as cough, fever, shortness of breath, muscle pain, fatigue, diarrhea, headache and sore throat, in addition to various clinical findings, such as loss of smell and taste. In this study, we aimed to reveal the loss of sense of taste and smell in COVID-19 patients and to investigate whether these sensory losses are permanent in the healing process of the disease. METHOD: This prospective study included 94 COVID-19 patients. Smell and taste tests were applied to all patients. Ten days after the first test, a second test was applied to the patients with an impaired sense of smell to compare the results. RESULTS: Of the 94 patients, 55.3% were male, and the mean age was 53 ± 19.6 (21-90) years. There were 67 patients with smell and taste impairment, of whom 34 (50.7%) had smell impairment only, 3 (4.4%) had taste impairment only, and 30 (44.7%) had both smell and taste impairment. It was found that the smell scores of 55 patients with smell and taste impairment in the first evaluation were significantly higher at the second measurement; and their tasting period was significantly shortened compared to the first measurement (p˂0.001). CONCLUSION: COVID-19 patients may present to medical centers with a broad variety signs and symptoms. This study shows that impairment in the senses of smell and taste is common in this disease and strongly associated with COVID-19 infection. However, smell and taste impairment is mostly temporary and improves during the recovery period.

Smell and Taste in Severe CoViD-19: Self-Reported vs. Testing.

One of the most striking reported symptoms in CoViD-19 is loss of smell and taste. The frequency of these impairments and their specificity as a potential central nervous system function biomarker are of great interest as a diagnostic clue for CoViD-19 infection as opposed to other similar symptomatologic diseases and because of their implication in viral pathogenesis. Here severe CoViD-19 was investigated by comparing self-report vs. testing of smell and taste, thus the objective severity of olfactory impairment and their possible correlation with other symptoms. Because a significant discrepancy between smell and taste testing vs. self-report results (p < 0.001) emerges in our result, we performed a statistical analysis highlighting disagreement among normosmia (p < 0.05), hyposmia, severe hyposmia, and anosmia (p < 0.001) and, in hypogeusia and severe hypogeusia, while no differences are observed in normogeusia and ageusia. Therefore, we analyzed the olfactory threshold by an objective test revealing the distribution of hyposmic (34%), severe hyposmic (48%), and anosmic (13%) patients in severe CoViD-19. In severe CoViD-19 patients, taste is lost in 4.3% of normosmic individuals, 31.9% of hyposmic individuals, 46.8% of severe hyposmic individuals, and 17% of anosmic individuals. Moreover, 95% of 100 CoViD-19 patients objectively tested were affected by smell dysfunction, while 47% were affected by taste dysfunction. Furthermore, analysis by objective testing also highlighted that the severity of smell dysfunction in CoViD-19 subjects did not correlate with age and sex. In conclusion, we report by objective testing that the majority of CoViD-19 patients report severe anosmia, that most of the subjects have olfactory impairment rather than taste impairment, and, finally, that the olfactory impairment correlate with symptom onset and hospitalization (p < 0.05). Patients who exhibit severe olfactory impairment had been hospitalized for about a week from symptom onset; double time has taken place in subjects with normosmia. Our results may be limited by the relatively small number of study participants, but these suggest by objective testing that hyposmia, severe hyposmia, and anosmia may relate directly to infection severity and neurological damage. The smell test assessment could be a potential screening symptom that might contribute to the decision to test suspected cases or guide quarantine instructions, further therapeutic approach, and evaluation of neurological damage.

Olfactory dysfunction in patients after recovering from COVID-19.

BACKGROUND: Smell and taste disorders occur in COVID-19 with a high prevalence, but little is known about the duration of the symptoms. In particular, studies using validated olfactory tests are very rare to date. AIMS/OBJECTIVES: The aim of this study was to determine the olfactory function of COVID-19 recoveries by a detailed olfactory test. METHODS: 91 patients with PCR-confirmed, past COVID-19 disease were included. Olfactory history was taken using a questionnaire. Olfactory function was evaluated with the sniffin' sticks test, tasting function with taste sprays. RESULTS: 80 patients had experienced sudden olfactory loss during the course of disease and at the time of testing, 33 patients subjectively still had an impaired olfactory sense. Around 8 weeks had passed since the onset of symptoms. 45.1% of the tested individuals were still hyposmic according to the olfactory test while 53.8% showed an olfactory performance within the normal range. Patients' self-assessment correlated poorly with the measured olfactory performance. CONCLUSIONS AND SIGNIFICANCE: Half of the patients with an olfactory loss as a symptom of COVID-19 still have olfactory impairments after two months, although not all of these patients subjectively notice a restriction. Long-term measurements must confirm whether all affected patients will make full recovery.

Prognosis of olfactory and gustatory dysfunctions in COVID-19 patients: A case series.

Although most COVID-19 patients feel their olfactory function returns to normal, the smell test demonstrates that a mild impairment of the olfactory function may have remained. Therefore, their olfactory function should be evaluated by a smell test.

Olfactory and gustatory abnormalities in COVID-19 cases.

PURPOSE: At the time of writing, there is a pandemic affecting virtually every country on Earth. There is considerable discussion amongst clinicians as well as lay people about anosmia and ageusia in COVID-19 sufferers. We aimed to report the results from comprehensive olfactory and gustatory testing in a series of hospital in-patients. METHODS: The prospective study evaluated 81 individuals with a COVID-19 infection, as confirmed by 2019 n-cov Real-Time PCR laboratory testing. The control group consisted of forty individuals with COVID-19 negative. Olfactory and gustatory testings were carried out by an examiner utilizing stringent safety standards and wearing full personal protective equipment. The results obtained in the case group were then compared with those obtained for the controls. RESULTS: In the case group, 41(50.6%) of patients were male and 40 (49.4%) were female, mean age of 54.16 ± 16.98 years (18-95). In the control group, 21 (52.5%) of subjects were male and 19 (47.5%) were female, and mean age was 55 ± 15.39 years (18-90). Fifty (61.7%) COVID-19-positive patients had complaints related to olfaction. The distribution of olfactory symptoms in the case group differed at the level of statistical significance from the control group (p < 0.001). Turning to gustatory abnormalities, within the case group, 22 individuals (27.2%) had taste malfunction. A statistically significant difference was found in the distribution of gustatory abnormalities between cases and controls (p < 0.001). CONCLUSIONS: Olfactory and gustatory dysfunctions are strongly associated with SARS-CoV-2 infection. Hyposmia with or without hypogeusia is potentially a reliable indicator of latent COVID-19.