Objective evaluation of anosmia and ageusia in COVID-19 patients: Single-center experience on 72 cases

Reduced olfactory bulb volume accompanies olfactory dysfunction after mild SARS-CoV-2 infection

Despite its high prevalence, the determinants of smelling impairment in COVID-19 remain not fully understood. In this work, we aimed to examine the association between olfactory bulb volume and the clinical trajectory of COVID-19-related smelling impairment in a large-scale magnetic resonance imaging (MRI) analysis. Data of non-vaccinated COVID-19 convalescents recruited within the framework of the prospective Hamburg City Health Study COVID Program between March and December 2020 were analyzed. At baseline, 233 participants underwent MRI and neuropsychological testing as well as a structured questionnaire for olfactory function. Between March and April 2022, olfactory function was assessed at follow-up including quantitative olfactometric testing with Sniffin' Sticks. This study included 233 individuals recovered from mainly mild to moderate SARS-CoV-2 infections. Longitudinal assessment demonstrated a declining prevalence of self-reported olfactory dysfunction from 67.1% at acute infection, 21.0% at baseline examination and 17.5% at follow-up. Participants with post-acute self-reported olfactory dysfunction had a significantly lower olfactory bulb volume at baseline than normally smelling individuals. Olfactory bulb volume at baseline predicted olfactometric scores at follow-up. Performance in neuropsychological testing was not significantly associated with the olfactory bulb volume. Our work demonstrates an association of long-term self-reported smelling dysfunction and olfactory bulb integrity in a sample of individuals recovered from mainly mild to moderate COVID-19. Collectively, our results highlight olfactory bulb volume as a surrogate marker that may inform diagnosis and guide rehabilitation strategies in COVID-19.

COVID-19: Unveiling the Neuropsychiatric Maze-From Acute to Long-Term Manifestations

The SARS-CoV-2 virus has spread rapidly despite implementing strategies to reduce its transmission. The disease caused by this virus has been associated with a diverse range of symptoms, including common neurological manifestations such as dysgeusia, anosmia, and myalgias. Additionally, numerous cases of severe neurological complications associated with this disease have been reported, including encephalitis, stroke, seizures, and Guillain-Barré syndrome, among others. Given the high prevalence of neurological manifestations in this disease, the objective of this review is to analyze the mechanisms by which this virus can affect the nervous system, from its direct invasion to aberrant activation of the immune system and other mechanisms involved in the symptoms, including neuropsychiatric manifestations, to gain a better understanding of the disease and thus facilitate the search for effective therapeutic strategies.

Sensitivity of Symptom-Based Screening for COVID-19 in Active Duty Basic Trainees

INTRODUCTION

Symptomatic Coronavirus Disease 2019 (COVID-19) screening has been a cornerstone of case identification during the pandemic. Despite the myriad of COVID-19 symptoms, symptom screens have primarily focused on symptoms of influenza-like illnesses such as fever, cough, and dyspnea. It is unknown how well these symptoms identify cases in a young, healthy military population. This study aims to evaluate the utility of symptom-based screening in identifying COVID-19 through three different COVID-19 waves.

MATERIALS AND METHODS

A convenience sample of 600 military trainees who arrived at Joint Base San Antonio-Lackland in 2021 and 2022 were included. Two hundred trainees with symptomatic COVID-19 before the emergence of the Delta variant (February-April 2021), when Delta variant was predominant (June-August 2021), and when Omicron was the predominant variant (January 2022) had their presenting symptoms compared. At each time point, the sensitivity of a screen for influenza-like illness symptoms was calculated.

RESULTS

Of the 600 symptomatic active duty service members who tested positive for COVID-19, the most common symptoms were sore throat (n = 385, 64%), headache (n = 334, 56%), and cough (n = 314, 52%). Although sore throat was the most prominent symptom during Delta (n = 140, 70%) and Omicron (n = 153, 77%), headache was the most common before Delta (n = 93, 47%). There were significant differences in symptoms by vaccination status; for example, ageusia was more common in patients who were not completely vaccinated (3% vs. 0%, P = .01). Overall, screening for fever, cough, or dyspnea had a 65% sensitivity with its lowest sensitivity in the pre-Delta cases (54%) and highest sensitivity in Omicron cases (78%).

CONCLUSIONS

In this descriptive cross-sectional study evaluating symptomatic military members with COVID-19, symptom prevalence varied based on predominant circulating COVID-19 variant as well as patients' vaccination status. As screening strategies evolve with the pandemic, changing symptom prevalence should be considered.

Comparison of the incidence of smell and taste disorders between influenza and COVID-19

OBJECTIVE

Smell and taste disorders among patients with COVID-19 has become increasingly reported in the literature, however the prevalence varies. Post-infectious respiratory dysfunction has also been linked to influenza. In this study, we aimed to compare the rates of smell and taste disorders between COVID-19 and Influenza in unvaccinated patients.

STUDY DESIGN

Retrospective cohort study.

SETTING

TriNetX research network.

METHODS

Two queries were made on 7/1/2023 to include Influenza without a diagnosis of COVID-19 and a COVID-19 without a diagnosis of Influenza. The queries included patients from January 1 to December 31, 2022 from 102 Healthcare Organizations. The resultant population of patients with ICD-10 codes for COVID-19 and Influenza were matched using demographic characteristics to evaluate the risk of smell disorders.

RESULTS

The overall 3-month incidence of smell and taste disorders was 0.73 % in the COVID-19 population and 0.1 % in the influenza population. The 3-month matched risk ratios were 11.1 [95 % CI (8.8,13.8)]; p < 0.001) times higher for disorders of the smell and taste secondary to COVID-19 compared to influenza.

CONCLUSIONS

Disorders of the smell and taste are more common among patients with COVID-19 compared to patients with Influenza. Beyond smell loss, patients experience additional nasal and sinus-related rhinological symptoms, pointing to COVID-19's and influenza's wider impact on overall rhinological health. We believe that due to the transient nature of these disorders, they might go underreported.

Atypical Complications during the Course of COVID-19: A Comprehensive Review

COVID-19 is primarily a respiratory disease, but numerous studies have indicated the involvement of various organ systems during the course of illness. We conducted a comprehensive review of atypical complications of COVID-19 with their incidence range (IR) and their impact on hospitalization and mortality rates. We identified 97 studies, including 55 research articles and 42 case studies. We reviewed four major body organ systems for various types of atypical complications: (i) Gastro-intestinal (GI) and hepatobiliary system, e.g., bowel ischemia/infarction (IR: 1.49-83.87%), GI bleeding/hemorrhage (IR: 0.47-10.6%), hepatic ischemia (IR: 1.0-7.4%); (ii) Neurological system, e.g., acute ischemic stroke/cerebral venous sinus thrombosis/cerebral hemorrhage (IR: 0.5-90.9%), anosmia (IR: 4.9-79.6%), dysgeusia (IR: 2.8-83.38%), encephalopathy/encephalitis with or without fever and hypoxia (IR: 0.19-35.2%); (iii) Renal system, e.g., acute kidney injury (AKI)/acute renal failure (IR: 0.5-68.8%); (iv) Cardiovascular system, e.g., acute cardiac injury/non-coronary myocardial injury (IR: 7.2-55.56%), arrhythmia/ventricular tachycardia/ventricular fibrillation (IR: 5.9-16.7%), and coagulopathy/venous thromboembolism (IR: 19-34.4%). This review encourages and informs healthcare practitioners to keenly monitor COVID-19 survivors for these atypical complications in all major organ systems and not only treat the respiratory symptoms of patients. Post-COVID effects should be monitored, and follow-up of patients should be performed on a regular basis to check for long-term complications.

Retinal nerve fiber layer thickness and peripapillary vasculature of post-COVID-19 patients with and without olfactory/gustatory dysfunction symptoms

PURPOSE

We aimed to compare retinal nerve fiber layer (RNFL) thickness and peripapillary vessel density values between COVID-19 patients with or without olfactory/gustatory dysfunction symptoms and healthy controls.

MATERIALS AND METHODS

We evaluated RNFL and radial peripapillary capillary vessel density (RPC-VD) values of 41 patients who had COVID-19 history and age- and gender-matched control group including 31 healthy individuals with optical coherence tomography angiography. First, post-COVID-19 group's and control group's RNFL and RPC-VD values were compared, then post-COVID-19 patients were divided into subgroups according to the presence (subgroup-A) and absence (subgroup-B) of olfactory/gustatory dysfunction symptoms, and same parameters were analyzed for subgroups.

RESULTS

Forty-one eyes of 41 post-COVID-19 patients and 31 eyes of 31 age- and gender-matched healthy controls were included in this cross-sectional study. In RNFL analysis, inferior sector thickness was found significantly lower in post-COVID-19 patients by comparison with control group (P = 0.041). In subgroup analyses, COVID-19 patients who first presented with olfactory/gustatory dysfunction symptoms had higher peripapillary and whole image optic disc capillary density (P = 0.011 and P = 0.002) compared to those who had not had these symptoms.

CONCLUSION

Lower RPC-VD and RNFL thickness were detected in COVID-19 patients compared to healthy controls. Higher Disc-VD values were found in COVID-19 patients with chemosensorial dysfunction (CSD) symptoms compared to those who had not had these symptoms probably due to milder disease course in COVID-19 with CSD. Sectorial RNFL attenuation in COVID-19 might have occurred secondary to peripapillary capillary circulation defect.

Chemosensory function recovery in COVID-19 patients: A cross-sectional study

OBJECTIVE

To determine whether subjects who have recovered from COVID-19 smell and taste disturbance perform similarly to their COVID-naïve baseline, on gold-standard smell and taste tests.

STUDY DESIGN

Prospective cross-sectional study.

SETTING

University of Miami Department of Otolaryngology in Miami, FL between September 2021, and August 2022.

METHODS

Those previously COVID-19 positive composed the experimental group, those who reported being COVID-naïve composed the control group. Mean total score for the UPSIT Smell Test, and the Burghart Taste Strip test were the primary outcome measures.

RESULTS

70 adult subjects (35 former COVID-positive, 35 COVID-naïve) were enrolled, with 21 females and 14 males in each group. 87 % of all subjects were white and were almost distributed evenly between Hispanic and non-Hispanic. Mean UPSIT total score for the experimental group was 30.6 (95 % CI 28.9-32.3), mean UPSIT total score for the control group was 31.2 (95 % CI 29.7-32.8). Mean Burghart total score for the experimental group was 11.3 (95 % CI 10.6-12.0), mean Burghart total score for the control group was 10.7 (95 % CI 9.7-11.8). These showed a significant overlap of the 95 % CI of the mean total score between the control group and the experimental group, suggesting no significant difference between the two groups.

CONCLUSION

These results suggest that COVID-19 patients who experience smell and taste disturbance and recover, regain sensory ability similar to their pre-COVID ability. Further study is needed to validate these findings, but the results are promising in the long-term recovery of COVID-19.

Assessment of anosmia/hyposmia in post-COVID-19 patients: a cross-sectional study in an eastern province of Saudi Arabia

Background and aim It has been shown that olfactory dysfunction is one of Coronavirus disease-2019 (COVID-19)common and puzzling symptoms that may persist weeks after the infection. This study aimed for the objective assessment of persisting olfactory dysfunction in post-COVID-19 patients. It also investigated the factors associated with the development of such symptoms in the Eastern Province of Saudi Arabia.

METHODS

A cross-sectional study that was conducted in the Department of Physiology, College of Medicine, Imam Abdulrahman bin Faisal University, Khobar, Saudi Arabia. One hundred and forty-seven participants were included in this study, and sixty of them agreed  to participate in the objective testing using the Connecticut Chemosensory Clinical Research Center (CCCRC) olfaction test.

RESULTS

There was a significant correlation between the following factors: (1) Persistence of anosmia/hyposmia and the time of onset of anosmia/hyposmia (P=0.015). (2) Persistence of anosmia/hyposmia and the duration of anosmia/hyposmia (P=0.012). (3) Duration of anosmia/hyposmia and the duration of COVID-19 symptoms (P=0.010). Interestingly, there was a significant association between the subjective participants' claim of anosmia/hyposmia and the score of their objective assessment (P=0.026).

CONCLUSION

The current study demonstrated that post-COVID-19 participants with delayed onset of anosmia/hyposmia and/or longer duration of either anosmia/hyposmia or COVID-19 symptoms were prone to have persistent olfactory dysfunction. Further studies are necessary to uncover the underlying pathophysiology and management of this olfactory dysfunction in COVID-19 patients.

Olfactory recovery following omicron variant infection: a psychophysical prospective case-control study with six-month follow up

OBJECTIVE

This study aimed to evaluate the recovery of olfactory function at six months in individuals infected with the coronavirus disease 2019 omicron variant, using psychophysical tests.

METHODS

A prospective case-control study that included severe acute respiratory syndrome coronavirus-2 patients infected in February and March 2022 was conducted. Patients underwent the Sniffin' Sticks test within 10 days of infection and again after at least 6 months. The olfactory scores were compared with those of a control group.

RESULTS

In all, 102 patients and 120 controls were enrolled in the study. At baseline, 26 patients (25.5 per cent) self-reported smell loss. The median threshold, discrimination and identification score was 33.6 (interquartile range, 12.5) for the cases and 36.5 (interquartile range, 4.38) for the controls (p < 0.001). Based on the threshold, discrimination and identification scores, 12 controls and 34 patients reported olfactory dysfunction (p < 0.001). Eighty cases underwent re-evaluation at six months; the median threshold, discrimination and identification score was 37.1 (interquartile range, 4.75) with no significant differences compared with the controls.

CONCLUSION

Six months after infection, the prevalence of olfactory dysfunction in patients did not differ significantly from the control population.

Evaluating long-term smell or taste dysfunction in mildly symptomatic COVID-19 patients: a 3-year follow-up study

INTRODUCTION

No studies have reported data on 3-year prevalence and recovery rates of self-reported COVID-19-related olfactory and gustatory dysfunction. The aim of the present study was to estimate the 3-year prevalence and recovery rate of self-reported COVID-19-related chemosensory dysfunction in a cohort of patients with antecedent mild COVID-19.

METHODS

This is a prospective observational study, measuring the prevalence of altered sense of smell or taste at follow-up and their variation from baseline, on adult patients consecutively assessed at Treviso and Trieste University Hospitals, who tested positive for SARS-CoV-2 RNA by polymerase chain reaction during March 2020.

RESULTS

Overall, out of 403 respondents, 267 patients (66.3%) reported an altered sense of smell or taste (SNOT-22 > 0) at baseline, while 56 (13.9%), 29 (7.2%), and 21 (5.2%) reported such alterations at 6-24 months, 2 years, and 3 years, respectively. Among the 267 patients with COVID-19-associated smell or taste dysfunction at baseline, 246 (92.1%) reported complete resolution at 3 years. Of the patients who still experienced smell or taste dysfunction 2 years after COVID-19, 27.6% and 37.9% recovered completely and partially, respectively, at the 3-year follow-up.

CONCLUSION

Among subjects with antecedent mildly symptomatic SARS-CoV-2 infection, the 3-year prevalence and recovery rate of COVID-19-related alteration in sense of smell or taste was 5% and 92%, respectively. In approximately two-thirds of patients experiencing chemosensory dysfunction still 2 years after COVID-19, it is still possible to observe a delayed complete or partial recovery after a period of 3 years, while the remaining one-third of individuals continues to have unchanged persistent chemosensory alteration.

Olfactory dysfunction among patients with COVID-19

OBJECTIVES

To assess the frequency of olfactory dysfunction (OD) among individuals afflicted with coronavirus disease of 2019 (COVID-19).

METHODS

A comprehensive literature search was carried out across several bibliographical databases (PubMed, Scopus, Google Scholar, and Web of Science) to extract publications in the English language between January 2020 and December 2021 to report the incidence of OD alone or together with gustatory dysfunction (GD) among COVID-19 patients.

RESULTS

Based on eligibility criteria, 84 articles were included from 27 countries, comprising 36,903 patients, of whom 58.1% were females. The generality rates of olfactory impairment alone was 34.60% and in conjunction with GD was 11.36%. Patients with OD were subclassified into various categories, and the prevalence of anosmia was 20.85%, 5.04% for hyposmia, 8.88% for anosmia or hyposmia, 1.84% for parosmia, 0.78% for phantosmia, and 0.02% for hyperosmia, among COVID-19 patients.

CONCLUSION

Clinical features associated with OD, either isolated or in combination with GD, are common in patients with COVID-19 and consider important signs of COVID-19 that may guide clinicians in the early phase of the disease.PROSPERO Reg. No.: 417296.

Transient loss and recovery of oral chemesthesis, taste and smell with COVID-19: A small case-control series

Transient loss of smell is a common symptom of influenza and other upper respiratory infections. Loss of taste is possible but rare with these illnesses, and patient reports of 'taste loss' typically arise from a taste / flavor confusion. Thus, initial reports from COVID-19 patients of loss of taste and chemesthesis (i.e., chemical somatosensation like warming or cooling) were met with skepticism until multiple studies confirmed SARS-CoV-2 infections could disrupt these senses. Many studies have been based on self-report or on single time point assessments after acute illness was ended. Here, we describe intensive longitudinal data over 28 days from adults aged 18-45 years recruited in early 2021 (i.e., prior to the Delta and Omicron SARS-CoV-2 waves). These individuals were either COVID-19 positive or close contacts (per U.S. CDC criteria at the time of the study) in the first half of 2021. Upon enrollment, all participants were given nose clips, blinded samples of commercial jellybeans (Sour Cherry and Cinnamon), and scratch-n-sniff odor identification test cards (ScentCheckPro), which they used for daily assessments. In COVID-19 cases who enrolled on or before Day 10 of infection, Gaussian Process Regression showed two distinct measures of function - odor identification and odor intensity - declined relative to controls (exposed individuals who never developed COVID-19). Because enrollment began upon exposure, some participants became ill only after enrollment, which allowed us to capture baseline ratings, onset of loss, and recovery. Data from these four cases and four age- and sex- matched controls were plotted over 28 days to create panel plots. Variables included mean orthonasal intensity of four odors (ScentCheckPro), perceived nasal blockage, oral burn (Cinnamon jellybeans), and sourness and sweetness (Sour Cherry jellybeans). Controls exhibited stable ratings over time. By contrast, COVID-19 cases showed sharp deviations over time. Changes in odor intensity or odor identification were not explained by nasal blockage. No single pattern of taste loss or recovery was apparent, implying different taste qualities might recover at different rates. Oral burn was transiently reduced for some before recovering quickly, suggesting acute loss may be missed in datasets collected only after illness ends. Collectively, intensive daily testing shows orthonasal smell, oral chemesthesis and taste were each altered by acute SARS-CoV-2 infection. This disruption was dyssynchronous for different modalities, with variable loss and recovery rates across both modalities and individuals.

Psychophysical assessment of olfactory and gustatory function in post-mild COVID-19 patients: A matched case-control study with 2-year follow-up

BACKGROUND

The aim of this study was to psychophysically evaluate the prevalence of smell and taste dysfunction 2 years after mildly symptomatic severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection compared to that observed at 1-year follow-up and while considering the background of chemosensory dysfunction in the no-coronavirus disease 2019 (COVID-19) population.

METHOD

This is a prospective case-control study on 93 patients with polymerase chain reaction (PCR)-positive SARS-CoV-2 infection and 93 matched controls. Self-reported olfactory and gustatory dysfunction was assessed by 22-item Sino-Nasal-Outcome Test (SNOT-22), item "Sense of smell or taste." Psychophysical orthonasal and retronasal olfactory function and gustatory performance were estimated using the extended Sniffin' Sticks test battery, 20 powdered tasteless aromas, and taste strips test, respectively. Nasal trigeminal sensitivity was assessed by sniffing a 70% solution of acetic acid.

RESULTS

The two psychophysical assessments of chemosensory function took place after a median of 409 days (range, 366-461 days) and 765 days (range, 739-800 days) from the first SARS-CoV-2-positive swab, respectively. At 2-year follow-up, cases exhibited a decrease in the prevalence of olfactory (27.9% vs. 42.0%; absolute difference, -14.0%; 95% confidence interval [CI], -21.8% to -2.6%; p = 0.016) and gustatory dysfunction (14.0% vs. 25.8%; absolute difference, -11.8%; 95% CI, -24.2% to 0.6%; p = 0.098). Subjects with prior COVID-19 were more likely than controls to have an olfactory dysfunction (27.9% vs. 10.8 %; absolute difference, 17.2%; 95% CI, 5.2% to 28.8%) but not gustatory dysfunction (14.0% vs. 9.7%; absolute difference, 4.3%; 95% CI, -5.8% to 14.4% p = 0.496) still 2 years after the infection. Overall, 3.2% of cases were still anosmic 2 years after the infection.

CONCLUSIONS

Although a proportion of subjects recovered from long-lasting smell/taste dysfunction more than 1 year after COVID-19, cases still exhibited a significant excess of olfactory dysfunction 2 years after SARS-CoV-2 infection when compared to matched controls.

Chemosensory Dysfunction 3-Months After COVID-19, Medications and Factors Associated with Complete Recovery

OBJECTIVES

To examine the longitudinal prevalence and recovery of olfactory, gustatory, and oral chemesthetic deficits in a sizable cohort of SARS-CoV-2 infected persons using quantitative testing. To determine whether demographic and clinical factors, mainly the medications used after the COVID-19 diagnosis, influence the test measures.

METHODS

Prospective cohort in a hospital with primary, secondary, tertiary, and quaternary care. Patients with confirmed COVID-19 were tested during the acute infection phase (within 15 days of initial symptom, n = 187) and one (n = 113) and 3 months later (n = 73). The University of Pennsylvania Smell Identification Test, the Global Gustatory Test, and a novel test for chemesthesis were administered at all visits.

RESULTS

During the acute phase, 93% were anosmic or microsmic and 29.4% were hypogeusic. No one was ageusic. A deficit in oral chemesthesis was present in 13.4%. By 3 months, taste and chemesthesis had largely recovered, however, some degree of olfactory dysfunction remained in 54.8%. Remarkably, patients who had been treated with anticoagulants tended to have more olfactory improvement. Recovery was greater in men than in women, but was unrelated to disease severity, smoking behavior, or the use of various medications prior to, or during, COVID-19 infection.

CONCLUSIONS

When using quantitative testing, olfactory disturbances were found in nearly all SARS-CoV-2 infected patients during the acute infection phase. Taste or chemesthetic deficits were low. Olfactory impairment persisted to some degree in over half of the patients at the 3-month follow-up evaluation, being more common in women and less common in those who had been treated earlier with anticoagulants.

LEVEL OF EVIDENCE

3.

Early treatment with low-molecular-weight heparin reduces mortality rate in SARS-CoV-2 patients

BACKGROUND

Since the beginning of the SARS-CoV-2 pandemic, millions of people have been infected and died. Different therapeutic approaches have been recommended, but only a few have shown clinical advantages. Low-molecular-weight heparin (LMWH) has been recommended to prevent COVID-19-related thrombo-embolic events. We aimed to evaluate the impact of early treatment with LMWH on hospital admission and death in patients with SARS-CoV-2 infection.

METHODS

We conducted an observational monocentric retrospective study to evaluate the preventive role of LMWH on the mortality rate of COVID-19 patients. SARS-CoV-2 infected patients were recruited from the beginning of the Italian epidemic to March 31, 2021. We excluded patients with missing data and those chronically exposed to LMWH. Treatment prescription was based on international and national guidelines and modified depending on clinical presentation and drug-drug interactions.

RESULTS

Seven hundred thirty-four SARS-CoV-2 infected patients were recruited, with 357 (48.6%) males and a median (IQR) age of 77.9 (65-85.7) years. 77.5% of people developed SARS-CoV-2-related symptoms and 62.8% were admitted to the hospital, and 20.2% died. Four hundred ninety-two (67%) started LMWH. In particular, 296 (40.3%) were treated within five days since symptoms onset. At logistic regression, early LMWH therapy was associated with lower mortality. Furthermore, remdesivir treatment showed a lower risk of death. On the contrary, age, BMI>30 kg/m2, neurological diseases, fever or dyspnea were associated with an increased risk of death.

CONCLUSIONS

Early treatment with LMWH was associated with lower mortality in our cohort. Further studies are needed to better assess the role of wider LMWH administration in terms of timing and regimen dose.

Recovery from olfactory and gustatory dysfunction following COVID-19 acquired during Omicron BA.1 wave in Italy

BACKGROUND

Despite alterations in the sense of smell and taste have dominated the symptoms of SARS-CoV-2 infection, the prevalence and the severity of self-reporting COVID-19 associated olfactory and gustatory dysfunction has dropped significantly with the advent of the Omicron BA.1 subvariant. However, data on the evolution of Omicron-related chemosensory impairment are still lacking.

OBJECTIVE

The aim of the present study was to estimate the prevalence and the recovery rate of self-reported chemosensory dysfunction 6-month after SARS-CoV-2 infection acquired during the predominance of the Omicron BA.1 subvariant in Italy.

METHODS

Prospective observational study based on the sino-nasal outcome tool 22 (SNOT-22), item "sense of smell or taste" and additional outcomes conducted in University hospitals and tertiary referral centers in Italy.

RESULTS

Of 338 patients with mild-to-moderate COVID-19 completing the baseline survey, 294 (87.0 %) responded to the 6-month follow-up interview. Among them, 101 (34.4 %) and 4 (1.4 %) reported an altered sense of smell or taste at baseline and at 6 months, respectively. Among the 101 patients with COVID-19-associated smell or taste dysfunction during the acute phase of the disease, 97 (96.0 %) reported complete resolution at 6 months. The duration of smell or taste impairment was significantly shorter in vaccinated patients (p = 0.007).

CONCLUSIONS

Compared with that observed in subjects infected during the first wave of the pandemic, the recovery rate from chemosensory dysfunctions reported in the present series of patients infected during the predominance of the Omicron BA.1 subvariant was more favorable with a shorter duration being positively influenced by vaccination.

Neurological complications and effects of COVID-19: Symptoms and conceivable mechanisms

A novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in December 2019 in Wuhan, China. The new coronavirus disease (COVID-19) was declared a global pandemic by the World Health Organization (WHO) in March 2020. SARS-CoV-2 can invade the nervous system aside from infecting the respiratory system as its primary target. The most common nervous system symptoms of COVID-19 are stated as headache, myalgia, fatigue, nausea, vomiting, sudden and unexplained anosmia, and ageusia. More severe conditions such as encephalomyelitis, acute myelitis, thromboembolic events, ischemic stroke, intracerebral hemorrhage, Guillain-Barré-syndrome, Bell's palsy, rhabdomyolysis, and even coma have also been reported. Cohort studies revealed that neurological findings are associated with higher morbidity and mortality. The neurological symptoms and manifestations caused by SARS-CoV-2 and COVID-19 are examined and summarized in this article.

What Is the Efficacy of Sotrovimab in Reducing Disease Progression and Death in People with COVID-19 during the Omicron Era? Answers from a Real-Life Study

(1) Introduction: Since May 2021, sotrovimab has been available in Italy for early treatment of SARS-CoV-2 infection and to prevent disease progression. However, some in vitro studies have questioned its efficacy on Omicron variants. Therefore, we aim to further investigate the efficacy of sotrovimab in real-life settings. (2) Methods: We conducted a retrospective study collecting medical records of people with SARS-CoV-2 infection evaluated in the infectious diseases units of Sassari, Foggia, and Bari, Italy. We included people with SARS-CoV-2 infection treated with sotrovimab and people who did not receive any treatment in 2022. The primary study outcome was to evaluate the efficacy of sotrovimab in reducing disease progression (defined as the necessity of starting oxygen supplementation) and COVID-19-related death. The secondary outcome was to evaluate the safety of sotrovimab. (3) Results: We included 689 people; of them, 341 were treated with sotrovimab, while 348 did not receive any treatment. Overall, we registered 161 (23.4%) disease progressions and 65 (9.4%) deaths, with a significant difference between treated and not-treated people (p < 0.001). In the multivariate logistic regression, increasing age [OR for ten years increasing age 1.23 (95%CI 1.04-1.45)] was associated with a higher risk of disease progression. In addition, cardiovascular disease [OR 1.69 (1.01-2.80), fever [OR 3.88 (95%CI 2.35-6.38)], and dyspnea [OR 7.24 (95%CI 4.17-12.58)] were associated with an increased risk of disease progression. In contrast, vaccination [OR 0.21 (95%CI 0.12-0.37)] and sotrovimab administration [OR 0.05 (95%CI 0.02-0.11)] were associated with a lower risk of developing severe COVID-19. Regarding mortality, people with older age [OR for ten years increasing age 1.36 (95%CI 1.09-1.69)] had a higher risk of death. In addition, in the multivariate analysis, cardiovascular disease lost statistical significance, while people on chemotherapy for haematological cancer [OR 4.07 (95%CI 1.45-11.4)] and those with dyspnea at diagnosis [OR 3.63 (95%CI 2.02-6.50)] had an increased risk of death. In contrast, vaccination [OR 0.37 (95%CI 0.20-0.68)] and sotrovimab treatment [OR 0.16 (95%CI 0.06-0.42)] were associated with lower risk. Only two adverse events were reported; one person complained of diarrhoea a few hours after sotrovimab administration, and one had an allergic reaction with cutaneous rash and itching. (4) Conclusions: Our study showed that sotrovimab treatment was associated with a reduction of the risk of disease progression and death in SARS-CoV-2-infected people, 70% of whom were over 65 years and a with high vaccination rate, with excellent safety. Therefore, our results reinforce the evidence about the efficacy and safety of sotrovimab during the Omicron era in a real-world setting.

Clinical characteristics and short-term outcomes of acute pancreatitis among patients with COVID-19

OBJECTIVE

The existing literature on the combination of acute pancreatitis (AP) and COVID-19 is scarce. The objective of our study is to compare the clinical outcomes and occurrence of long COVID syndrome in AP patients with and without COVID-19, while investigating the potential impact of COVID-19 on the severity, mortality rate, and long COVID syndrome in these patients.

METHODS

This retrospective, observational study was conducted at a single center. It included patients aged 18 years and above who were diagnosed with AP during the pandemic. Patients were categorized into two groups based on the results of RT-qPCR testing: the SARS-CoV-2-positive group and the SARS-CoV-2-negative group. The study aimed to compare the severity of AP, mortality rate, and occurrence of long COVID syndrome between these two groups.

RESULT

A retrospective review was conducted on 122 patients diagnosed with acute pancreatitis between December 1, 2022, and January 31, 2023. Out of these patients, 100 were included in the study. The analysis revealed no significant differences in mortality rate, severity, and sequelae between AP patients with COVID-19 and those without COVID-19 (p > 0.005). However, a statistically significant difference was observed in the occurrence of long COVID syndrome, specifically in the presence of cough (p = 0.04).

CONCLUSION

This study demonstrates that the presence of COVID-19 in patients with pancreatitis does not lead to an increase in the mortality and severity rate of pancreatitis.

COVID-19 in the nervous system: physiopathology and neurological manifestations

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a viral infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although respiratory manifestations have received greater visibility during the pandemic caused by this virus, numerous neurological complaints related to coronavirus 2 infection have been documented in several countries. These records suggest that this pathogen presents neurotropism, and it can cause different neurological conditions of varying intensity.

OBJECTIVE

To investigate the ability of coronavirus 2 to invade the central nervous system (CNS) and its neurological clinical outcomes.

METHODS

The present study consists in a comprehensive literature review of the records available in the PubMed, SciELO, and Google Scholar databases. The descriptors COVID-19, brain and physiopathology, associated with the Boolean operator AND, were used in the search. Regarding the inclusion and exclusion criteria, we selected the papers published since 2020 with the highest number of citations.

RESULTS

We selected 41 articles, most of them in English. The main clinical manifestation associated with COVID-19 patients was headache, but cases of anosmia, hyposmia, Guillain-Barré syndrome, and encephalopathies were also described with considerable frequency.

CONCLUSION

Coronavirus-2 presents neurotropism, and it can reach the CNS by hematogenous dissemination and by direct infection of the nerve endings. It causes brain injuries through several mechanisms, such as cytokine storm, microglial activation, and an increase in thrombotic factors.

Post-viral olfactory loss and parosmia

The emergence of SARS-CoV-2 has brought olfactory dysfunction to the forefront of public awareness, because up to half of infected individuals could develop olfactory dysfunction. Loss of smell-which can be partial or total-in itself is debilitating, but the distortion of sense of smell (parosmia) that can occur as a consequence of a viral upper respiratory tract infection (either alongside a reduction in sense of smell or as a solo symptom) can be very distressing for patients. Incidence of olfactory loss after SARS-CoV-2 infection has been estimated by meta-analysis to be around 50%, with more than one in three who will subsequently report parosmia. While early loss of sense of smell is thought to be due to infection of the supporting cells of the olfactory epithelium, the underlying mechanisms of persistant loss and parosmia remain less clear. Depletion of olfactory sensory neurones, chronic inflammatory infiltrates, and downregulation of receptor expression are thought to contribute. There are few effective therapeutic options, so support and olfactory training are essential. Further research is required before strong recommendations can be made to support treatment with steroids, supplements, or interventions applied topically or injected into the olfactory epithelium in terms of improving recovery of quantitative olfactory function. It is not yet known whether these treatments will also achieve comparable improvements in parosmia. This article aims to contextualise parosmia in the setting of post-viral olfactory dysfunction, explore some of the putative molecular mechanisms, and review some of the treatment options available.

The immune mechanism of the nasal epithelium in COVID-19-related olfactory dysfunction

During the first waves of the coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, olfactory dysfunction (OD) was reported as a frequent clinical sign. The nasal epithelium is one of the front-line protections against viral infections, and the immune responses of the nasal mucosa may be associated with OD. Two mechanisms underlying OD occurrence in COVID-19 have been proposed: the infection of sustentacular cells and the inflammatory reaction of the nasal epithelium. The former triggers OD and the latter likely prolongs OD. These two alternative mechanisms may act in parallel; the infection of sustentacular cells is more important for OD occurrence because sustentacular cells are more likely to be the entry point of SARS-CoV-2 than olfactory neurons and more susceptible to early injury. Furthermore, sustentacular cells abundantly express transmembrane protease, serine 2 (TMPRSS2) and play a major role in the olfactory epithelium. OD occurrence in COVID-19 has revealed crucial roles of sustentacular cells. This review aims to elucidate how immune responses of the nasal epithelium contribute to COVID-19-related OD. Understanding the underlying immune mechanisms of the nasal epithelium in OD may aid in the development of improved medical treatments for COVID-19-related OD.

Neurofilament Expression as a Biomarker of Post-COVID-19 Sudden Sensorineural Hearing Loss

Sudden sensorineural hearing loss (SSHL) affects a patient's quality of life and requires rapid treatment. The etiology is viral, vascular, and autoimmune, even though, in most cases, it remains idiopathic SSHL. Since 2019, several different complications have been identified following COVID-19 infection. The post-COVID-19 ENT manifestations reported in the literature are sore throat, headache, pharyngeal erythema, nasal obstruction, rhinorrhea, upper respiratory tract infection, and tonsil enlargement. Cases of SSHL, vestibular neuronitis, and audio-vestibular disorders (such as tinnitus, dizziness, and vertigo) have also been reported, albeit in a smaller percentage of patients. We reported our experience of a case of post-COVID-19 SSHL in the absence of any other type of post-COVID symptoms or brain and internal auditory canal magnetic resonance imaging and magnetic resonance angiography modifications. We aimed to identify a serological biomarker of sudden sensorineural hearing loss, and we also dosed and monitored the value of the serum neurofilament light (NfL). the best of our knowledge, this is the first report that associates SSHL and the serological increase in NfL as a potential biomarker of neuronal-disease-related damage.

Subjective Perception of Recovery and Measured Olfactory Function in COVID-19 Patients

This cross-sectional study aimed to investigate self-rated olfactory dysfunction in relation to measured olfactory function after partial or complete subjective recovery in individuals with a history of coronavirus disease 2019 (COVID-19) infection. A total of 186 individuals (aged 5-62 years) with a history of COVID-19 infection were included. Visual analogue scale (VAS) ratings for olfactory function (before, during, and after infection) and age-appropriate psychophysical olfactory test scores (odor threshold and odor identification: "Sniffin' Sticks" for adults and both "Sniffin' Sticks" and "U-Sniff" for children) were determined. Participants were assigned to four "age groups" and three "recovery classes" (incomplete recovery, complete recovery, no smell loss). Surprisingly, there were no significant differences in odor threshold and adult identification scores between the "recovery classes". However, children with "incomplete recovery" had lower identification scores than those with "complete recovery" (p = 0.033) and those with "no smell loss" (p = 0.022). The pediatric age groups had significantly higher VAS ratings during and after COVID-19 compared to older participants. Older individuals experienced greater magnitude of changes in their sense of smell after COVID-19 infection, but those with parosmia were 3.5 times more likely to report "incomplete recovery" of olfaction after COVID-19. The general prognosis for olfactory recovery after COVID-19 is good but appears to be particularly confounded by the presence of parosmia, leading patients to subjectively report incomplete olfactory recovery. Although it is of high significance to monitor recovery using validated psychophysical olfactory tests, subjective measures of olfaction help provide specific insight, especially for qualitative olfactory dysfunction.

Transient Anosmia and Dysgeusia in COVID-19 Disease: A Cross Sectional Study

Objective

This study aims to explore the prevalence of anosmia and dysgeusia and their impact on COVID-19 patients.

Methods

This is a cross-sectional study. Patients diagnosed with COVID-19 between 1st October 2020 and 30th June 2021 were randomly selected from a national COVID-19 registry. COVID-19 cases were diagnosed using molecular testing method which measured the viral E gene. The Anosmia Reporting Tool, and a brief version of the questionnaire on olfactory disorders were used to measure the outcomes via telephone interviews. Data were analysed using SPSS 27 statistics software.

Results

A total of 405 COVID-19 adults were included in this study, 220 (54.3%) were males and 185 (45.8%) were females. The mean±SD age of participants was 38.2 ± 11.3 years. Alterations in the sense of smell and taste were reported by 206 (50.9%), and 195 (48.1%) of the patients, respectively. Sex and nationality of participants were significantly associated with anosmia and dysgeusia (p < 0.001) and (p-value=0.001) respectively. Among patients who experienced anosmia and dysgeusia, alterations in eating habits (64.2%), impact on mental wellbeing (38.9%), concerns that the alterations were permanent (35.4%), and physical implications and difficulty performing activities of daily living (34%) were reported.

Conclusion

Anosmia and dysgeusia are prevalent symptoms of COVID-19 disease, especially among females. Although transient, anosmia and dysgeusia had considerable impact on patient's life. Neuropsychological implications of COVID-19 in acute infection phase and prognosis of anosmia and dysgeusia in COVID-19 are areas for further exploration.

Prevalence of Chemosensitive Neurological Disorders of Smell and Taste and Association with Blood Groups in SARS-CoV-2 Patients: Cross-Sectional Study

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has caused a highly challenging and threatening situation worldwide. SARS-CoV-2 patients develop various clinical symptoms. The olfactory and taste dysfunctions are potential neurological manifestations among SARS-CoV-2 patients; however, their relationship with blood groups has rarely been investigated. This study aimed to investigate the prevalence of chemosensitive neurological disorders of smell and taste and their association with blood groups in SARS-CoV-2 patients. The present cross-sectional study was performed in the Department of Pathology, and Physiology, College of Medicine, King Saud University, Riyadh, Saudi Arabia. A well-structured, self-administered questionnaire was designed and distributed through social media platforms. A total of 922 Saudi and non-Saudi adults aged 18 years or older participated in the study. Out of 922 participants, the number of people who had anosmia was 309 (33.5%), 211 (22.9%) had hyposmia, and 45 (4.8%) had dysosmia. Moreover, 180 (19.52%) had ageusia, 47 (5.1%) and 293 (31.8%) had hypogeusia and dysgeusia, respectively. Among all the participants, 565 (61.27%) had smell-related disorders and 520 (56.39%) participants had taste-related clinical symptoms. The occurrence of anosmia and ageusia was relatively high among females compared to males (p = 0.024). The prevalence of smell-related disorders was 25.0% (230) and taste-related disorders was 23.21% (214) among the study participants with blood group O compared to all other blood group (A, B, and AB) participants who have smell allied disorders 30.69% (283), and taste allied disorders 27.98% (258). The prevalence of chemosensitive neurological disorders involving impaired smell and taste was higher in SARS-CoV-2 patients. These clinical symptoms were common among the participants with blood group type O compared to all other ABO blood group types. The role of certain demographic characteristics was consistent throughout multiple studies, notably with female gender and young adults.

Diode laser in management of loss of taste sensation in patients with post-COVID syndrome: a randomized clinical trial

OBJECTIVE

Loss of taste (ageusia) is a symptom observed following recovery from COVID-19 infection. The loss of taste and smell sensation may negatively affect patients' quality of life (QoL). The present study aimed to evaluate the effectiveness of the Diode Laser in managing loss of taste sensation in patients with post-COVID syndrome versus the placebo.

MATERIAL AND METHOD

The study sample was 36 patients who complained of persistent loss of taste sensation following COVID-19. The patients were randomly assigned to one of the two groups according to the received treatment: Group I (laser treatment) and Group II (light treatment), with each patient receiving a diode laser treatment or placebo from the same operator. Taste sensation was subjectively measured after treatment for four weeks.

RESULTS

The results demonstrated a significant difference between both groups regarding taste restoration after one month (p = 0.041), with Group II having a significantly higher percentage of cases 7 (38.9%) with partial taste restoration. In contrast, a significantly higher proportion of Group I 17 cases (94.4%) had complete taste restoration (p < 0.001).

CONCLUSION

The present study concluded that using a Diode laser 810 nm aided in a more rapid recovery from loss of taste dysfunction.

Structural insights into SARS-CoV-2 main protease conformational plasticity

The spread of different severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants underscores the need for insights into the structural properties of its structural and non-structural proteins. The highly conserved homo-dimeric chymotrypsin-like protease (3CL M^PRO ), belonging to the class of cysteine hydrolases, plays an indispensable role in processing viral polyproteins that are involved in viral replication and transcription. Studies have successfully demonstrated the role of M^PRO as an attractive drug target for designing antiviral treatments because of its importance in the viral life cycle. Herein, we report the structural dynamics of six experimentally solved structures of M^PRO (i.e., 6LU7, 6M03, 6WQF, 6Y2E, 6Y84, and 7BUY including both ligand-free and ligand-bound states) at different resolutions. We have employed a structure-based balanced forcefield, CHARMM36m through state-of-the-art all-atoms molecular dynamics simulations at µ-seconds scale at room temperature (303K) and pH 7.0 to explore their structure-function relationship. The helical domain-III responsible for dimerization mostly contributes to the altered conformational states and destabilization of M^PRO . A keen observation of the high degree of flexibility in the P5 binding pocket adjoining domain II-III highlights the reason for observation of conformational heterogeneity among the structural ensembles of M^PRO . We also observe a differential dynamics of the catalytic pocket residues His41, Cys145, and Asp187, which may lead to catalytic impairment of the monomeric proteases. Among the highly populated conformational states of the six systems, 6LU7 and 7M03 forms the most stable and compact M^PRO conformation with intact catalytic site and structural integrity. Altogether, our findings from this extensive study provides a benchmark to identify physiologically relevant structures of such promising drug targets for structure-based drug design and discovery of potent drug-like compounds having clinical potential.

Transient loss and recovery of oral chemesthesis, taste and smell with COVID-19: a small case-control series

Anosmia is common with respiratory virus infections, but loss of taste or chemesthesis is rare. Reports of true taste loss with COVID-19 were viewed skeptically until confirmed by multiple studies. Nasal menthol thresholds are elevated in some with prior COVID-19 infections, but data on oral chemesthesis are lacking. Many patients recover quickly, but precise timing and synchrony of recovery are unclear. Here, we collected broad sensory measures over 28 days, recruiting adults (18-45 years) who were COVID-19 positive or recently exposed (close contacts per U.S. CDC criteria at the time of the study) in the first half of 2021. Participants received nose clips, red commercial jellybeans (Sour Cherry and Cinnamon), and scratch-n-sniff cards (ScentCheckPro). Among COVID-19 cases who entered the study on or before Day 10 of infection, Gaussian Process Regression showed odor identification and odor intensity (two distinct measures of function) each declined relative to controls (close contacts who never developed COVID-19), but effects were larger for intensity than identification. To assess changes during early onset, we identified four COVID-19 cases who enrolled on or prior to Day 1 of their illness â€" this allowed for visualization of baseline ratings, loss, and recovery of function over time. Four controls were matched for age, gender, and race. Variables included sourness and sweetness (Sour Cherry jellybeans), oral burn (Cinnamon jellybeans), mean orthonasal intensity of four odors (ScentCheckPro), and perceived nasal blockage. Data were plotted over 28 days, creating panel plots for the eight cases and controls. Controls exhibited stable ratings over time. By contrast, COVID-19 cases showed sharp deviations over time. No single pattern of taste loss or recovery was apparent, implying different taste qualities might recover at different rates. Oral burn was transiently reduced for some before recovering quickly, suggesting acute loss may be missed in data collected after acute illness ends. Changes in odor intensity or odor identification were not explained by nasal blockage. Collectively, intensive daily testing shows orthonasal smell, oral chemesthesis and taste were each altered by acute COVID-19 infection, and this disruption was dyssynchronous for different modalities, with variable loss and recovery rates across modalities and individuals.

COVID-19 in the Eastern Brazilian Amazon: Incidence, Clinical Management, and Mortality by Social Determinants of Health, Symptomatology, and Comorbidities in the Xingu Health Region

This study aims to investigate the relationship between social determinants of health (SDH), incidence, and mortality to verify which sociodemographic factors, symptoms, and comorbidities predict clinical management; second, this study aims to conduct a survival analysis of individuals with COVID-19 in the Xingu Health Region. Consequently, this study adopted an ecological framework, employing secondary data of COVID-19-positive individuals from the Xingu Health Region, Pará State, Brazil. The data were obtained through the database of the State of Pará Public Health Secretary (SESPA) for the period from March 2020 to March 2021. The incidence and mortality were higher in Vitória do Xingu and Altamira. Municipalities with a higher percentage of citizens with health insurance and higher public health expenditure showed a higher incidence and mortality. A higher gross domestic product was associated with a higher incidence. Females were found to be associated with better clinical management. To live in Altamira was a risk factor for intensive care unit admission. The symptoms and comorbidities that predicted worse clinical management were dyspnea, fever, emesis, chills, diabetes, cardiac and renal diseases, obesity, and neurological diseases. There were higher incidence, mortality, and lower survival rates among the elderly. Thus, it can be concluded that SDH indicators, symptomatology, and comorbidities have implications for the incidence, mortality, and clinical management of COVID-19 in the Xingu Health Region of eastern Amazonia, Brazil.

Persistent olfactory learning deficits during and post-COVID-19 infection

Quantifying olfactory impairments can facilitate early detection of Coronavirus disease 2019 (COVID-19). Despite being a debated topic, many reports provide evidence for the neurotropism of SARS-CoV-2. However, a sensitive, specific, and accurate non-invasive method for quantifying persistent neurological impairments is missing to date. To quantify olfactory detectabilities and neurocognitive impairments in symptomatic COVID-19 patients during and post-infection periods, we used a custom-built olfactory-action meter (OAM) providing accurate behavioral readouts. Ten monomolecular odors were used for quantifying olfactory detectabilities and two pairs of odors were employed for olfactory matching tests. We followed cohorts of healthy subjects, symptomatic patients, and recovered subjects for probing olfactory learning deficits, before the Coronavirus Omicron variant was reported in India. Our method identifies severe and persistent olfactory dysfunctions in symptomatic patients during COVID-19 infection. Symptomatic patients and recovered subjects showed significant olfactory learning deficits during and post-infection periods, 4-18 months, in comparison to healthy subjects. On comparing olfactory fitness, we found differential odor detectabilities and olfactory function scores in symptomatic patients and asymptomatic carriers. Our results indicate probable long-term neurocognitive deficits in COVID-19 patients imploring the necessity of long-term tracking during post-infection period. Differential olfactory fitness observed in symptomatic patients and asymptomatic carriers demand probing mechanisms of potentially distinct infection routes.

Late onset and persistent parosmia and dysgeusia as neurosensorial complication by the SARS virus COV 2

About the neurological manifestations of COVID-19, smell impairment with some distortion or parosmia is currently one of the longest-lasting post-covid sequelae affecting many young adults around the world, we present a case of a 25yo patient that after the COVID-19 infection initiates with anosmia and dysgeusia of difficult control and some weeks later begins with parosmia associated to general discomfort and vomiting preceded by nausea, accompanied by poor oral intake, generating weight loss in 3 weeks, and depression probably related to the clinical profile and the confinement due to the pandemic. She was treated with prednisone, gabapentin, nasal irrigations and olfactory rehabilitation, with mild improvement, which was greater after the second dose of covid-19 vaccine.

Olfactory impairment in patients with coronavirus disease 2019 self-perceived as asymptomatic

BACKGROUND

Olfactory impairment may be present among patients with coronavirus disease 2019 self-perceived as asymptomatic. This study aimed to assess olfactory function among these individuals.

METHODS

A cross-sectional study involving patients with coronavirus disease 2019 self-perceived as asymptomatic was conducted. Assessments included the subjective Malaysian Smell and Taste Questionnaire and the culturally adapted Malaysian version of the objective Sniffin' Sticks Identification smell test.

RESULTS

In 81 participants (mean age of 31.59 ± 12.04 years), with mean time from diagnosis to smell test of 7.47 ± 3.79 days, subjective assessment showed that 80.2 per cent were asymptomatic (questionnaire score of 6) and 19 per cent had mild symptoms (questionnaire score of 7 and 8). The mean objective smell test score was 10.89 ± 2.11. The prevalence of olfactory impairment was 76.6 per cent among patients with coronavirus disease 2019 self-perceived as asymptomatic. There was no association between the questionnaire and the smell test scores (p = 0.25). There was a correlation between the smell test score and the duration from diagnosis to smell test (p = 0.04).

CONCLUSION

The objective assessment demonstrated that coronavirus disease 2019 patients who perceived themselves as asymptomatic showed olfactory impairment.

Pediatric COVID-19 Involving Complicated Sinusitis With Intracranial Extension and Lemierre Syndrome: A Case Report

Pediatric coronavirus disease 2019 (COVID-19) has been associated with various complications including chronic respiratory disease and multisystem inflammatory syndrome. There are a few reported cases of complicated sinusitis following pediatric COVID-19 infection. We present a patient with recent COVID-19 who developed complicated sinusitis with intracranial extension and Lemierre syndrome. A 16-year-old female with a history of COVID-19 diagnosis 17 days prior presented with worsening head and neck symptoms. Physical examination demonstrated left proptosis, cranial nerve (CN) VI palsy, and limited neck range of motion. Imaging demonstrated bilateral sinus disease, a 3.3 × 2 × 3-centimeter sellar/clival abscess, bilateral cavernous sinus thrombosis, and thrombosis of bilateral internal jugular veins. Urgent endoscopic sinus surgery was performed, and long-term intravenous antibiotics and anticoagulation were initiated with improvement in symptoms over three weeks. Providers caring for patients with COVID-19 should keep complicated sinusitis and Lemierre syndrome in their differential. Further study of COVID-19 pathophysiology in the sinonasal mucosa is needed.

Olfactory and taste dysfunction in COVID-19-incidence and recovery

Background

Olfactory and taste dysfunctions have been identified as prominent signs of COVID-19 infection. The data on its prevalence, time of onset, and recovery is highly variable.

Objective

The study was aimed at establishing the incidence of and the factors influencing smell and taste disorders in COVID-19-affected patients.

Methodology

Telephonic interviews were used to collect data on the symptoms of COVID-19-positive patients, with an emphasis on smell and taste disorders. Patients have severe disease and a history of illnesses that may affect olfaction or taste, and those unwilling to participate were excluded.

Results

A total of 1488 COVID-19-positive patients were identified. A total of 772 were included and interviewed, and their data were analysed. A total of 242 (31.3%) patients developed symptoms related to smell and/or taste. Anosmia (149) and ageusia (152) were the most common. Younger patients were more commonly affected (p = 0.0016). The presence and degree of smell symptoms and taste symptoms showed a small positive correlation (r = .234, p < .001). A strong relationship was seen with fever (r = .825, p < .001) and a significantly moderate relationship with breathing difficulty. There was no significant difference based on age or sex for the recovery of smell or taste sensations. There was a significant correlation between taste recovery and smell recovery times (p < 0.00001).

Conclusion

Smell and taste disorders, as early clinical symptoms of COVID-19, may have a diagnostic as well as a prognostic value. Treatment protocols for these patients are yet to be defined. A positive association between these symptoms and breathing difficulty was found, and we recommend COVID-19 testing and monitoring of symptoms for all patients with new-onset OTD symptoms. A combination of active enquiry about these symptoms, along with objective testing when the patients present with COVID-19 symptoms may help in better understanding of the pathophysiology and timely initiation of treatment.

Covid-19 affects taste independently of smell: results from a combined chemosensory home test and online survey from a global cohort (N=10,953)

People often confuse smell loss with taste loss, so it is unclear how much gustatory function is reduced in patients self-reporting taste loss. Our pre-registered cross-sectional study design included an online survey in 12 languages with instructions for self-administering chemosensory tests with ten household items. Between June 2020 and March 2021, 10,953 individuals participated. Of these, 3,356 self-reported a positive and 602 a negative COVID-19 diagnosis (COVID+ and COVID-, respectively); 1,267 were awaiting test results (COVID?). The rest reported no respiratory illness and were grouped by symptoms: sudden smell/taste changes (STC, N=4,445), other symptoms excluding smell or taste loss (OthS, N=832), and no symptoms (NoS, N=416). Taste, smell, and oral irritation intensities and self-assessed abilities were rated on visual analog scales. Compared to the NoS group, COVID+ was associated with a 21% reduction in taste (95% Confidence Interval (CI): 15-28%), 47% in smell (95%-CI: 37-56%), and 17% in oral irritation (95%-CI: 10-25%) intensity. In all groups, perceived intensity of smell (r=0.84), taste (r=0.68), and oral irritation (r=0.37) was correlated. Our findings suggest most reports of taste dysfunction with COVID-19 were genuine and not due to misinterpreting smell loss as taste loss (i.e., a classical taste-flavor confusion). Assessing smell and taste intensity of household items is a promising, cost-effective screening tool that complements self-reports and helps to disentangle taste loss from smell loss. However, it does not replace standardized validated psychophysical tests.

Loss of Sour Taste Is the Striking Feature among Four Basic Taste Qualities in Tunisian COVID-19 Patients

BACKGROUND

Taste disorders (TDs) have been reported to be very common in patients suffering from coronavirus disease 2019 (COVID-19), which is caused by the SARS-CoV-2 virus. In most of the hitherto conducted studies, a gustatory assessment was performed on the basis of surveys or self-reports by patients. The aim of our study was to undertake an objective assessment of four basic taste qualities by conducting tasting sessions that allowed detection thresholds in COVID-19 Tunisian patients and to study their associations with inflammation.

METHODS

This analytical cross-sectional study was conducted on 89 patients aged between 21 to 70 years who had been diagnosed with COVID-19. We used Burghart taste strips to assess taste perception of the four taste qualities, i.e., sour, bitter, sweet, and salty. Serum levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), and C-reactive protein (CRP) were measured.

RESULTS

Taste disorders were reported by 40.4% of the patients, while objective assessments revealed that 63.8% of participants were suffering from hypogeusia and/or ageusia. Sour taste was the most altered (70.8%) gustatory quality. Patients with severe COVID-19 had significantly lower sour and bitter taste scores when compared to patients with minor/moderate forms. There was no significant association between serum inflammatory markers and taste disorders. However, the relationship between bitter and sweet taste qualities and IL-1β levels was significant (p = 0.018 and p = 0.041).

CONCLUSIONS

Our results demonstrate the interest in the objective assessment of taste dysfunctions in COVID-19 patients.

Analysis of Interaction Between Odorant Receptors and Flexible Spike of SARS CoV-2- Key to Loss of Smell

BACKGROUND

The development of a vaccine for SARS-CoV-2 is primarily focused on the structure of the spike (S) protein. The heavy glycosylation of S with flexible hinges at the stalk shields from antibody attachment.

OBJECTIVE

This study deciphers the flexible nature of hinges responsible for binding the odorant receptor on neurons responsible for the loss of smell in COVID-19 patients.

METHODS

The 3D structure via EPIK in Maestro, protein docking with ligands via Maestro protein analysis tool, and molecular dynamic simulation at 30 ns run using DESMOND was prepared.

RESULTS

The data of the study strongly suggest that strong and stable bond formation results from the reaction between R:14: Trp and Phe at the residue, targeting the flexible hinges of SARS-CoV-2. The difference in the conformational structure of the S protein and its binding with the odorant receptor in COVID-19 is the prime factor for the loss of smell and taste in patients, as supported by the concept of Antigen (epitope) Antibody interaction by the stable formation of a hydrogen bond among odorant receptor and the S protein. The flexibility of structural proteins determines the binding potential of antibodies or other defense proteins produced to participate in the antigen-antibody reaction.

CONCLUSION

Molecular and atomic details potentiate the design and screening of small molecules that can inhibit the fusion at entry level or odorant receptors and potentially be used in the prevention and treatment of infection, particularly when formulated as nasal drops, paving a new approach for pharmacologists in the treatment of COVID-19 infection.

Taste loss as a distinct symptom of COVID-19: a systematic review and meta-analysis

Chemosensory scientists have been skeptical that reports of COVID-19 taste loss are genuine, in part because before COVID-19 taste loss was rare and often confused with smell loss. Therefore, to establish the predicted prevalence rate of taste loss in COVID-19 patients, we conducted a systematic review and meta-analysis of 376 papers published in 2020-2021, with 235 meeting all inclusion criteria. Drawing on previous studies and guided by early meta-analyses, we explored how methodological differences (direct vs. self-report measures) may affect these estimates. We hypothesized that direct measures of taste are at least as sensitive as those obtained by self-report and that the preponderance of evidence confirms taste loss is a symptom of COVID-19. The meta-analysis showed that, among 138,015 COVID-19-positive patients, 36.62% reported taste dysfunction (95% confidence interval: 33.02%-40.39%), and the prevalence estimates were slightly but not significantly higher from studies using direct (n = 15) versus self-report (n = 220) methodologies (Q = 1.73, df = 1, P = 0.1889). Generally, males reported lower rates of taste loss than did females, and taste loss was highest among middle-aged adults. Thus, taste loss is likely a bona fide symptom of COVID-19, meriting further research into the most appropriate direct methods to measure it and its underlying mechanisms.

Covid-19 affects taste independent of taste-smell confusions: results from a combined chemosensory home test and online survey from a large global cohort

People often confuse smell loss with taste loss, so it is unclear how much gustatory function is reduced in patients self-reporting taste loss. Our pre-registered cross-sectional study design included an online survey in 12 languages with instructions for self-administering chemosensory tests with 10 household items. Between June 2020 and March 2021, 10,953 individuals participated. Of these, 5,225 self-reported a respiratory illness and were grouped based on their reported COVID test results: COVID-positive (COVID+, N = 3,356), COVID-negative (COVID-, N = 602), and COVID unknown for those waiting for a test result (COVID?, N = 1,267). The participants who reported no respiratory illness were grouped by symptoms: sudden smell/taste changes (STC, N = 4,445), other symptoms excluding smell or taste changes (OthS, N = 832), and no symptoms (NoS, N = 416). Taste, smell, and oral irritation intensities and self-assessed abilities were rated on visual analog scales. Compared to the NoS group, COVID+ was associated with a 21% reduction in taste (95% confidence interval (CI): 15-28%), 47% in smell (95% CI: 37-56%), and 17% in oral irritation (95% CI: 10-25%) intensity. There were medium to strong correlations between perceived intensities and self-reported abilities (r = 0.84 for smell, r = 0.68 for taste, and r = 0.37 for oral irritation). Our study demonstrates that COVID-19-positive individuals report taste dysfunction when self-tested with stimuli that have little to none olfactory components. Assessing the smell and taste intensity of household items is a promising, cost-effective screening tool that complements self-reports and may help to disentangle taste loss from smell loss. However, it does not replace standardized validated psychophysical tests.

Exploring the research landscape of COVID-19-induced olfactory dysfunction: A bibliometric study

Since the outbreak of COVID-19, olfactory dysfunction (OD) has become an important and persistent legacy problem that seriously affects the quality of life. The purpose of this paper is to quantitatively analyze and visualize the current research status and development trend of COVID-19 related OD by using VOSviewer software. Based on the Web of Science database, a total of 1,592 relevant documents were retrieved in January 2023, with publication time spanning from 2020 to 2023. The bibliometric analysis revealed that the most influential research results in the field of COVID-19 related OD were concentrated in journals of related disciplines such as otorhinolaryngology, medicine, general and internal, virology, neurosciences, etc. The knowledge base of the research is mainly formed in two fields: COVID-19 clinical research and OD specialized research. The research hotspots are mainly concentrated in six directions: COVID-19, long COVID, smell, anosmia, OD, and recovery. Based on the results of the bibliometric analysis, the temporal trends of COVID-19 related OD studies were visually revealed, and relevant suggestions for future research were proposed.

Smell and taste disorders in pregnant women with COVID-19

   Background. Smell disorder is a recognized clinical symptom of COVID-19 infection. The problem of the loss of sense of smell in the structure of COVID-19 pathogenesis during pregnancy remains unresolved.   The aim of the study. To determine the sense of smell and taste in pregnant women with COVID-19, as well as to evaluate the relationship between the sense of smell and the number of SARS-CoV-2 genome equivalents in the nasopharyngeal secretion.   Material and methods. In the case-control study, 121 pregnant women participated: 40 of them were infected with COVID-19; 81 were not infected with COVID-19 earlier and at the time of the study. The survey was conducted in July 2021. Sense of smell was assessed using the Connecticut Chemosensory Clinical Research Center (CCCRC) olfactory test, which includes olfactory threshold determination and odor identification assessment. Taste was measured according to the O. Massarelli method. Viral load was calculated using a standardized method for determining the numberof SARS-CoV-2 RNA copies in 1 ml of nasopharyngeal secretion.   Results. The incidence of olfactory disorders (moderate / severe and anosmia) in pregnant women with COVID-19 is 62.5 % compared to 22.23 % among pregnant women who have never had COVID-19 (p = 0.002). No significant taste disorders were identified. The threshold value for the manifestation of olfactory disorders was 17794 RNA copies of the SARS-CoV-2 virus, which corresponds to the 37th threshold cycle (Ct).   Conclusion. During pregnancy in the acute phase of COVID-19, sense of smell is significantly impaired, but not sense of taste. Decreased sense of smell is associated with SARS-CoV-2 viral load.

Olfactory evaluation in hospitalised and self-isolated patients with COVID-19: a single-centre experience on 55 cases

BACKGROUND

Smell loss is a common symptom of COVID-19 infection. Majority of the studies that evaluated olfactory impairment in COVID-19 used questionnaires (subjective smell evaluations) and did not compare the results with objective or semiobjective measures of smell. We performed smell testing in hospitalised and self-isolated patients with COVID-19 and control participants.

METHODS

Fifty-five COVID-19 and 44 control participants underwent smell testing, using Burghart Sniffin' Sticks 'Screening 12 Test'. Participants also rated their smelling capability on the numerical scale. Differences between groups and correlation between smell loss and time from acute onset of symptoms were tested, as well as correlation between results of smell test and subjective assessment of smell.

RESULTS

Hospitalised patients with COVID-19 correctly determined 6.5/12 odorants compared with 10/12 in the self-isolated and 11/12 in the control group (p<0.001). Hyposmia or anosmia were present in 87.5% of hospitalised and 29.0% of self-isolated patients (p<0.001). The correlation between subjective self-assessment and results of smell testing was non-significant in both groups of patients with COVID-19, while there was a moderate positive correlation (p=0.001, Spearman's correlation coefficient=0.499) in control participants.

CONCLUSION

Contrary to some previous reports suggesting that the presence of olfactory loss may predict milder course of disease, our study found that a vast majority of hospitalised patients with COVID-19 had prominent olfactory impairment. The absence of correlation between self-rated and objective smell evaluation in patients with COVID-19 indicates that subjective smell assessment is unreliable.

Patient factors associated with COVID-19 loss of taste or smell patient factors in smell/taste loss COVID-19

Objectives

Dysfunction in smell or taste is well recognized phenomenon in patients infected with SARS-CoV-2. This study aimed to quantify the incidence and associated co-morbidities of reported olfactory or gustatory dysfunction in patients who tested positive for SARS-CoV-2.

Methods

From March 23, 2020 through July 31, 2020, 192,683 patients were tested for SARS-CoV-2 at Mayo Clinic. These patients with a positive test were contacted via telephone by physicians at Mayo Clinic and information gathered on patient demographics, comorbidities, symptoms and clinical risk stratification based on these factors.

Results

Two thousand two hundred and fifty patients tested positive for SARS-CoV-2 (1.2%). Six hundred and sixty-seven (29.6%) of these patients reported loss of smell or taste. Factors found to be correlated with reporting loss of smell or taste on multivariate analysis were: younger age, female sex, or symptoms of chest pain or tightness, cough, or headache and lower clinical risk category. Coronary artery disease (CAD) was associated with not reporting loss of taste or smell.

Conclusion

Of 2250 patients testing positive for SARS-CoV-2 at Mayo Clinic, 667 reported loss of taste and smell. Patients who reported loss of smell or taste were younger, female and more likely to report cough, chest pain, headache, or history of chronic obstructive pulmonary disease (COPD), but overall had fewer high-risk comorbidities. Those who were older, male, and a reported history of CAD were less likely to report chemosensory dysfunction. Our data are the largest single institution data reporting COVID-19 associated loss of smell or taste, and the first to associate COPD and CAD as factors that affect rates of reported chemosensory dysfunction.

Level of evidence

IIB.

Olfactory testing as COVID-19 screening in school children; A prospective cross-sectional study

BACKGROUND

Little is known about olfactory changes in pediatric COVID-19. It is possible that children under-report chemosensory changes on questionnaires, similar to reports in adults. Here, we aim to describe COVID-19-related olfactory dysfunction in outpatient children. We hypothesized that children with COVID-19 will demonstrate abnormal olfaction on smell-identification testing at a higher rate than children with negative COVID-19 testing.

METHODS

A prospective cross-sectional study was undertaken from June 2020-June 2021 at a tertiary care pediatric hospital. A consecutive sample of 205 outpatients aged 5-21 years undergoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) PCR testing were approached for this study. Patients with prior olfactory dysfunction were excluded. Participants were given a standard COVID-19 symptom questionnaire, a Smell Identification Test (SIT) and home-odorant-based testing within 2 weeks of COVID-19 testing. Prior to study enrollment, power calculation estimated 42 patients to determine difference in rates of SIT results between groups. Data were summarized with descriptive statistics.

RESULTS

Fifty-one patients underwent smell identification testing (23 positive (45%) and 28 negative (55%) for COVID-19; mean age 12.7 years; 60% female). 92% of all patients denied subjective change in their sense of smell or taste but only 58.8% were normosmic on testing. There was no difference in screening questionnaires or SIT scores between COVID-19 positive and negative groups.

CONCLUSIONS

Unlike adults, there was no statistical difference in olfactory function between outpatient COVID-19 positive and negative children. Our findings suggest a discrepancy between objective and patient-reported olfactory function in pediatric patients, and poor performance of current screening protocols at detecting pediatric COVID-19.

Post-Viral Olfactory Loss: What We Learned from the SARS-CoV-2 Pandemic

Viral infections have always been one of the most frequent causes of persistent olfactory dysfunctions accounting for 18% to 45% of all cases [...].

Effects of COVID-19 on sensory and cognitive perception of mild and severe diagnosed and recovered patients versus healthy consumers

The objective of this research was to analyze the effects of the SARS-CoV-2 virus on the sensory and cognitive perception of mild and severe COVID-19 diagnosed and recovered consumers versus healthy consumers. Three groups of 50 consumers each (healthy vs. mild and severe COVID-19 diagnosed with 30 days after recovery) were used for the evaluation of instant coffee stimuli in concentrations: 4.40, 2.93, 2.20, 1.76, and 1.47% weight (w)/volume (v) and determine their discriminating power, emotions, and memories. Sensory tests were performed remotely. Results indicated that healthy consumers perceived higher intensities in most of the sensory attributes (with the exception of Burnt-A, Bitter-T, Acid-T, and Astringent-T attributes) compared to consumers who presented mild and severe COVID-19. Therefore, consumers diagnosed with mild and severe COVID-19 had a higher discrimination power in the attributes smell, basic tastes, and flavor. Healthy consumers could only discriminate two attributes that correspond to basic flavors. Consumers with mild and severe COVID-19 diagnosis elicited the highest number of negatives emotions (such as bored, disgusted, worried, guilty, wild, and aggressive) and negative memories (disease, pain, death, hurt, obesity, conflict personal, addiction, stench poverty, and accident) than healthy consumers. It is concluded that there were no significant differences between the consumer panels for the identification of sensory attributes. However, P-Healthy consumers perceived the highest intensities in most sensory attributes compared to those in the PCOVID19-Mild and PCOVID19-Severe panels. Finally, consumers diagnosed with mild or severe COVID-19 used a higher number of emotions and memories than those of the healthy panel.

Practical applications

Investigating the effects of COVID-19 on sensory and cognitive perception can be useful for industry and researchers in the sensory field who wish to understand the effects of the disease in order to generate new protocols for the selection and training of people, as well as the possible development and innovation of new products focused on perception of consumers recovered from COVID-19.