Prevalence of Long COVID-associated symptoms in adults with and without SARS-CoV-2 infection in Germany: Results of the population-based study: Corona Monitoring Nationwide 2021/22 (RKI-SOEP-2) (preprint)

Background Controlled population-based studies on long-term health sequelae of SARS-CoV-2 can help to identify clinical signs specific to Long COVID and to evaluate this emerging public health challenge. Aim To examine prevalence differences of Long COVID-associated symptoms among adults with and without SARS-CoV-2 infection in Germany. Methods This population-based, retrospective study (11/2021-2/2022) included 7,683 working aged adults (18-65 years), a subset of the Corona Monitoring Nationwide study in Germany. Prior SARS-CoV-2 infection was defined based on self-reported PCR-confirmed infections and IgG-antibody dried blood spot testing. Participants answered a questionnaire including 19 common symptoms of Long COVID experienced in the six months preceding the survey. We estimated population-weighted prevalence of (1) individual symptoms, and (2) [≥]1 symptom, with and without impact on work ability, by infection status within strata of sex, age group, income and comorbidity. We calculated model-adjusted prevalence differences and the probability that symptoms among infected are attributable to infection. Results 12 of 19 symptoms showed a significantly higher prevalence in infected than non-infected participants, including fatigue (27.5% versus 18.3%; p<0.001), concentration problems (22.2% vs. 13.1%; p<0.001), shortness of breath (15.6% vs. 7.5%; p<0.001), and smell and taste disorder (10% vs. 1.2%; p<0.001). [≥]1 symptom with impact on work ability was more prevalent following infection (16.0% vs. 12.2%; p=0.06) with a model-adjusted prevalence difference of 3.8% (95%-CI -0.5-8.0). Conclusion We observed a rather small excess prevalence attributable to SARS-CoV-2 infection. However, the absolute number of persons places great demands on the health care system and may affect economic productivity.

A Comprehensive Comparative Analysis of Deep Learning based Feature Representations for Molecular Taste Prediction (preprint)

Taste determination in small molecules is critical in food chemistry, but traditional experimental methods can be time-consuming. Consequently, computational techniques have emerged as val-uable tools for this task. In this study, we explore taste prediction using various molecular feature representations and assess the performance of different machine learning algorithms on a dataset comprising 2,601 molecules. The results reveal that GNN-based models outperform other ap-proaches in taste prediction. Moreover, consensus models that combine diverse molecular repre-sentations demonstrate improved performance. Among these, molecular fingerprints + GNN con-sensus model emerges as the top performer, highlighting the complementary strengths of GNNs and molecular fingerprints. These findings have significant implications for food chemistry research and related fields. By leveraging these computational approaches, taste prediction can be expedited, leading to advancements in understanding the relationship between molecular structure and taste perception in various food components and related compounds.

Dysosmia and dysgeusia as differential diagnostics for clinical triaging of COVID-19 cases (preprint)

Smell and taste disorders are recognized as frequent, and often the only, signs occurring in the early phase of SARS-Cov-2 infection and in many cases perdure as post-viral symptoms. This evidence raised a general reconsideration of chemosensory deficits, further suggesting that their appearance can be considered as a discriminative and predictive tool to detect COVID-19 cases. In this study, encompassing the first and second pandemic wave, participants estimated their olfactory and gustatory sensitivity, plus they were administered the validated Brief Smell Identification Test (BSIT). We observed that smell and taste impairments were mainly experienced by COVID-19-positive subjects with comparable severity of respiratory symptoms as non-COVID-19 patients. In addition, we noticed that the diagnostic power of subjective olfactory assessments upon SARS-Cov-2 infection is comparable to quantitative evaluation, suggesting that self-reporting could be adopted as the first line of intervention, anticipating more exhaustive procedures aimed at containing COVID-19 diffusion and consequently preserving general health. Overall, results from this work share similarity with other studies, therefore further underlying that olfactory and gustatory disbalance can be distinctive hallmarks in COVID-19 continuum.

Intranasal lavage with hypochlorous acid safely reduces the symptoms in the ambulatory patient with COVID-19. (preprint)

ABSTRACT OBJECTIVE This study was designed to investigate intranasal lavage with a hypochlorous acid solution in the reduction of symptoms in the ambulatory COVID-19 patient. STUDY DESIGN Study approval granted by the Institutional Review Board of Reading Hospital (IRB 036-20), with informed consent obtained from all adult participants(age>18 years). SETTING All enrollees, taken from the same ambulatory testing facility, received nasopharyngeal swabs for COVID-19 testing by reverse transcription polymerase chain (RT-PCR) or the COVID-19 antigen specific test (Binax NOW, Abbott Lab) METHODS Convenience sampling methodology was utilized. Each enrollee was provided with the study devices which included a Nasaflo Neti Pot (NeilMed Pharmaceutical, Inc.), and the hypochlorous acid solution (Vashe Wound Solution, Urgo Medical North America, LLC). Participants were instructed to irrigate each nostril with 120 cc (four ounces) of the solution for ten consecutive days, and record the presence or absence of symptoms in a scripted diary log. RESULTS The study included 88 patients of which 74 (84.1%) completed the ten days of nasal lavage. All data analysis was conducted using SPSS version 25.0. Chi square test of association found no significant difference related to gender, age group race, ethnicity, residence, or living arrangements (all p-values > 0.05). There were no statistical differences in any of the co-morbid conditions. Mild adverse reactions included burning, epistaxis, and oral metallic taste. No enrollees required mechanical ventilation. There were no deaths. CONCLUSION This study suggests the feasibility and safety of using intranasal lavage with a hypochlorous acid solution in relieving symptoms in the ambulatory Covid-19 patient.

Prevalence of Post COVID-19 Condition among healthcare workers: self-reported online survey in four African countries (preprint)

The impact of Post COVID-19 Condition is ongoing despite the declaration that the COVID-19 pandemic has ended. In this study, we explore the prevalence of PCC among healthcare workers (HCWs) in four African Countries and its influence on their professional performance. This study was conducted as an online cross-sectional survey of healthcare workers from four African countries (Cameroon, Egypt, Nigeria, and Somalia) between the 20th of December 2021 to 12th of January 2022. We determined the prevalence of PCC based on the WHO case definition and assessed variables associated with a higher prevalence of PCC in these countries using univariable and multivariable logistic regression analyses. A total of 706 HCWs from four African countries were included in this survey. Most of the HCWs were aged between 18-34 years (75.8%, n=535). Our findings showed that 19.5% (n=138) of the HCWs had tested positive for SARS-CoV-2. However, 8.4% (n=59) were symptomatic for COVID-19 but tested negative or were never tested. Two-thirds of the HCWs (66.4%, n=469)have received a COVID-19 vaccine and 80.6% (n=378) of those vaccinated had been fully vaccinated. The self-reported awareness rate of PCC among the HCWs was 16.1% (n=114/706) whereas the awareness rate of PCC among COVID-19-positive HCWs was 55.3 % (n=109/197). The prevalence of PCC among HCWs was 58.8% (n=116). These changes include the self-reported symptoms of PCC which included headache (58.4%, n=115), fatigue (58.8%, n=116), and muscle pain (39.6%, n=78). Similarly, 30% (n=59) and 20.8% (n=41) of the HCWs reported the loss of smell and loss of taste long after their COVID-19 infection, respectively. Some HCWs (42%, n=83) believed that their work performance has been affected by their ongoing symptoms of PCC. There was no significant difference in the prevalence of PCC among the vaccinated and unvaccinated HCWs (p > 0.05). Of the socio-demographic variables, age (older HCWs between 45-54 years; OR:1.7; 95% CI: 1.06, 10.59; p = 0.001) and location (Egypt; OR:14.57; 95% CI: 2.62, 26.76; p = 0.001) were more likely to have experienced PCC than other age groups and countries respectively. The study revealed low prevalence of PCC among the surveyed HCC. In addition, it observed the need for adequate medical and psychological support to HCWs with PCC, improve their COVID-19 vaccination uptake, and conduct mass advocacy campaigns on PCC.

Assessment of the relationship between Google Trend search data on clinical symptoms and cases reported during the first wave of the COVID-19 outbreak in India. (preprint)

Infodemiology and infoveillance approaches have been extensively used in recent years to support traditional epidemiology and disease surveillance. Hence, the present study aimed to explore the association between Google Trends (GTs) search of clinical symptoms and cases reported during the first wave of COVID-19. The GT data from January 30, 2020, to September 30, 2020, and daily COVID-19 cases in India and a few selected states were collected from the Ministry of Health and Family Welfare, Government of India. Correlation analysis was performed between the GT index values and the number of confirmed cases. Followed by, the COVID-19 cases were predicted using Bayesian regression and classical linear regression models. A strong association was observed between the search index of clinical symptoms and reported COVID-19 cases (cold: R=0.41, headache: R=0.46, fever: R=0.66, loss of taste: R=0.78, loss of smell R=0.86) across India. Similarly, lagged correlations were also observed (loss of smell, loss of taste, loss of taste and loss of smell, fever and headache show 3, 9, 1, 9, and 13 days lag periods respectively). Besides this, the Bayesian regression model was outperformed (MAE: 0.331164, RMSE: 0.411087) for predicting the COVID-19 cases in India and regionally than the frequentist linear regression (MAE: 0.33134, RMSE: 0.411316). The study helps health authorities better prepare and planning of health care facility timely to avoid adverse impacts.

A patient-centered view of symptoms, functional impact, and priorities in post-COVID-19 syndrome: Cross-sectional results from the Quebec Action Post-COVID cohort (preprint)

Background: Health services planning and mechanism-focused research would benefit from a clearer picture of symptoms, impact, and personal priorities in post-COVID-19 syndrome (PCS). This study aimed to provide estimates of the symptom, function, and quality of life (QOL) impact of PCS. Methods: People living in Quebec, aged 18 and over, were eligible for the Quebec Action for/pour le Post-COVID (QAPC) study if they had symptoms lasting more than 4 weeks post-acute SARS-CoV-2 infection, with or without a positive COVID-19 test. Recruitment was through conventional and social media between September 2022-January 2023. Standardized and individualized questionnaires, in French or English, were accessed through an online portal. We report cross-sectional results from the baseline visit of the first 414 participants in this ongoing longitudinal study. Results: Individuals spontaneously reported symptoms attributable to an average of 4.5 organ systems. Fatigue was most frequent. Effects on function and quality of life were moderate to severe, and had already persisted for a year or more in the majority. Personal intervention priorities included fatigue and post-exercise malaise, cognitive symptoms, shortness of breath, and impaired taste and smell. Women and men were similar on PCS impact, while older age was associated with lower impact. Interpretation: Symptom clusters defined a range of severity, with fatigue a pervasive symptom at all levels of severity. Participants in this study are likely to be representative of those seeking health care for post-COVID-19 symptoms in Canada and the results can inform next steps for clinical, research, and health services planning.

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.

COVID-19 Sequelae and Their Implications on Social Services.

BACKGROUND: The impact of persistent coronavirus disease 2019 (COVID-19) symptoms on quality of life remains unclear. This study aimed to describe such persistent symptoms and their relationships with quality of life, including clinical frailty and subjective health status. METHODS: A prospective longitudinal 3-month follow-up survey monitored symptoms, health quality, support needs, frailty, and employment. RESULTS: A total of 82 patients with a mean age of 52 years (ranging from 23-84 years) were enrolled, including 48 (58.6%) men, and 34 (41.5%) women. The fully active status decreased from 87.8% before admission to 78.1% post discharge. Two patients (2.4%) were ambulatory and capable of all self-care but unable to carry out any work-related activities 12 weeks after discharge. Clinical frailty scale (CFS) levels 1, 2, 3 and 4 changed drastically between admission and 12 weeks later after discharge. Just after admission, the median EuroQol visual analogue scales (EQ-VAS) was 82.23 (± 14.38), and it decreased to 78.10 (± 16.02) 12 weeks after discharge; 62 (75.6%) of patients reported at least one symptom 12 weeks after discharge. The most frequent symptom was fatigue followed by smell disorder, anxiety, sleep disorder, headache, depressive mood, dyspnea, and taste disorder. CFS was definitively associated with fatigue. Decreased EQ-VAS was associated with fatigue and palpitation, cough, taste disorder, and chest pain. EQ-VAS was worse in women (28%) than in men. Compared with regular outpatient clinic visits before admission, 21 patients (25.6%) reported increased outpatient clinic visits, one (1.4%) reported readmission, and one (1.4%) reported emergency room visits. Six of the 54 (77.1%) patients who were employed before admission lost their jobs. And most vulnerable type was self-employed, because three self-employed job workers were not working at 12 weeks after discharge. CONCLUSION: COVID-19 sequelae should not be underestimated. We find a decrease in health quality and increase in psychological problems in discharged COVID-19 patients, and some patients experience unemployment. The number of patients suffering from COVID-19 sequelae would not be negligible considering there are more than one million COVID-19 infection cases in Korea. Hence, the government should start a systematic monitoring system for discharged patients and prepare timely medical and social interventions accordingly.

Antibody response, associated symptoms and profile of patients presumably infected by SARS-CoV-2 with taste or smell disorders in the SAPRIS multicohort study.

BACKGROUND: Taste or smell disorders have been reported as strongly associated with COVID-19 diagnosis. We aimed to identify subject characteristics, symptom associations, and antibody response intensity associated with taste or smell disorders. METHODS: We used data from SAPRIS, a study based on a consortium of five prospective cohorts gathering 279,478 participants in the French general population. In the analysis, we selected participants who were presumably infected by SARS-CoV-2 during the first epidemic wave. RESULTS: The analysis included 3,439 patients with a positive ELISA-Spike. Sex (OR = 1.28 [95% CI 1.05-1.58] for women), smoking (OR = 1.54 [95% CI 1.13-2.07]), consumption of more than 2 drinks of alcohol a day (OR = 1.37 [95% CI 1.06-1.76]) were associated with a higher probability of taste or smell disorders. The relationship between age and taste or smell disorders was non-linear. Serological titers were associated with taste or smell disorders: OR = 1.31 [95% CI 1.26-1.36], OR = 1.37 [95% CI 1.33-1.42] and OR = 1.34 [95% CI 1.29-1.39] for ELISA-Spike, ELISA-Nucleocapsid and seroneutralization, respectively. Among participants with taste or smell disorders, 90% reported a wide variety of other symptoms whereas 10% reported no other symptom or only rhinorrhea. CONCLUSIONS: Among patients with a positive ELISA-Spike test, women, smokers and people drinking more than 2 drinks a day were more likely to develop taste or smell disorders. This symptom was strongly associated with an antibody response. The overwhelming majority of patients with taste or smell disorders experienced a wide variety of symptoms.

Prevalence of taste and smell dysfunction in mild and asymptomatic COVID-19 patients during Omicron prevalent period in Shanghai, China: a cross-sectional survey study.

OBJECTIVES: COVID-19, which is caused by SARS-CoV-2, is a severe threat to human health and the economy globally. This study aimed to investigate the prevalence of taste and/or smell dysfunction and associated risk factors in mild and asymptomatic patients with Omicron infection in Shanghai, China.DesignThis was a questionnaire-based cross-sectional study. SETTING: COVID-19 patients at the makeshift hospital in the Shanghai World Expo Exhibition and Convention Centre were recruited from March to April 2022. PARTICIPANTS: In total, 686 COVID-19-infected patients who were defined as mild or asymptomatic cases according to the diagnostic criteria of New Coronavirus Pneumonia Prevention and Control Programme ninth edition (National Health Commission of China, 2022) were enrolled. MEASURES: Data to investigate taste and smell loss and to characterise other symptoms were collected by the modified Chemotherapy-induced Taste Alteration Scale and Sino-Nasal Outcome Test-22 questionnaires. The risk factors for the severity of taste/smell dysfunction were analysed by binary logistic regression models. RESULTS: 379 males (379/686, 55.2%) and 307 females (307/686, 44.8%) completed the questionnaires to record recent changes in taste and smell ability. A total of 302 patients (44%) had chemosensory dysfunction with Omicron infection, of which 22.7% (156/686) suffered from both taste and smell dysfunction. In addition, cough (60.2%), expectoration (40.5%), fever (33.2%) and sore throat (32.5%) were common symptoms during Omicron infection. The quality-of-life-related indicators were negatively associated with participants' self-reported taste and smell dysfunction. CONCLUSIONS: The prevalence of taste or/and smell dysfunction in patients with Omicron infections was 44%. Individuals with chemosensory dysfunction had significantly higher rates of various upper respiratory influenza-like symptoms, xerostomia and bad breath. Moreover, smell dysfunction was a risk factor for the prevalence of taste dysfunction in patients with Omicron infection. TRIAL REGISTRATION NUMBER: ChiCTR 2200059097.

[Mechanisms and Management of COVID-19-Associated Taste Disorders].

The taste buds in the human tongue contain specialized cells that generate taste signals when they are stimulated. These signals are then transmitted to the central nervous system, allowing the human body to distinguish nutritious substances from toxic or harmful ones. This process is critical to the survival of humans and other mammals. A number of studies have shown that dysgeusia, or taste disorder, is a common complication of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which can severely affect patients' nutritional intake and quality of life. Based on the physiological process of taste perception, the direct causes of dysgeusia include dysfunction of taste receptors and damage to the taste nervous system, while indirect causes include genetic factors, aging-related changes, bacterial and viral infections, and cancer treatments such as radiotherapy and chemotherapy. The pathogenic factors of dysgeusia are complicated, further research is needed to fully understand the underlying mechanisms, and some of the reported findings and conclusions still need further validation. All these form a great challenge for clinical diagnosis of the cause and targeted treatment of dysgeusia. Herein, we reviewed published research on the physiological process of taste perception, the potential mechanisms of taste disorders related to SARS-CoV-2 infection, and strategies for prevention and treatment, providing theoretical support for establishing and improving the comprehensive management of COVID-19 complicated by taste disorders.

Quantitative but not qualitative flavor recognition impairments in COVID-19 patients.

BACKGROUND: Smell and taste dysfunctions (STDs) are symptoms associated with COVID-19 syndrome, even if their incidence is still uncertain and variable. AIMS: In this study, the effects of SARS-CoV-2 infection on chemosensory function have been investigated using both a self-reporting questionnaire on smell and flavor perception, and a simplified flavor test. METHODS: A total of 111 subjects (19 hospitalized [HOS] and 37 home-isolated [HI] COVID-19 patients, and 55 healthy controls [CTRL]) were enrolled in the study. They received a self-evaluation questionnaire and a self-administered flavor test kit. The flavor test used consists in the self-administration of four solutions with a pure olfactory stimulus (coffee), a mixed olfactory-trigeminal stimulus (peppermint), and a complex chemical mixture (banana). RESULTS: After SARS-CoV-2 infection, HOS and HI patients reported similar prevalence of STDs, with a significant reduction of both smell and flavor self-estimated perception. The aromas of the flavor test were recognized by HI and HOS COVID-19 patients similarly to CTRL; however, the intensity of the perceived aromas was significantly lower in patients compared to controls. CONCLUSION: Data reported here suggests that a chemosensory impairment is present after SARS-CoV-2 infection, and the modified "flavor test" could be a novel self-administering objective screening test to assess STDs in COVID-19 patients. CLINICAL TRIAL REGISTRATION NO: NCT04840966; April 12, 2021, retrospectively registered.

Recovery from Covid-19 smell loss: Two-years of follow up.

OBJECTIVE: To report long-term patterns of recovery and non-recovery in a large nationwide cohort of subjects with COVID-19 associated smell loss. STUDY DESIGN: Prospectively, longitudinal questionnaires. SETTING: Web-based national survey. METHODS: A longitudinal survey of adults with COVID-19 and/or sudden change in smell or taste since January 1, 2020 was launched April 10, 2020. Participants were queried again in late May 2022 regarding recovery. Data from respondents with >2 years since loss were analyzed and compared to recovery status of those more recently effected. RESULTS: 1103 responded to the survey of whom 946 met inclusion criteria. Among the 267 respondents for whom at least 2 years of follow up was available, 38.2 % reported full recovery, 54.3 % partial, and 7.5 % no recovery. For the entire cohort (all with ≥3 months since smell loss), 38.7 % reported complete recovery, 51.0 % reported partial recovery (ranging from mild complaints to severe phantosmia or dysosmia), and 10.3 % reported no improvement at all. Complete recovery of smell function was significantly higher in those under 40 years old (45.6 % compared to 32.9 % in those over 40). CONCLUSION: Although the vast majority of subjects who do recover do so within the first 3 months, long-term spontaneous recovery can occur. Rates of recovery do not seem to differ depending on when during the pandemic the loss first occurred.

Transient loss and recovery of oral chemesthesis, taste and smell with COVID-19 (preprint)

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: 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.

Novel Protocol Using a Comprehensive Training ‘N’ Treatment (TNT) Approach Rapidly Reverses Olfactory and Gustatory Dysfunction in Patients with Acute Loss of Taste and Smell Induced by SARS-CoV-2 Infection (preprint)

Infection with SARS-CoV-2 causes COVID-19 and has a well-established set of clinical symptoms. Olfactory and gustatory dysfunction are among the non-life threatening sequalae observed with both acute and chronic SARS-CoV-2 infection. This can lead to the loss of taste and smell and has been observed in large subsets of COVID-19 patients. Although non-life threatening, loss of taste and smell can contribute to decreased quality of life and prevent sufficient nutrient intake, which may negatively affect prognosis and recovery. Despite progress in the treatment of other symptoms caused by COVID-19, there are currently no standardized treatment protocols to mitigate loss of taste and smell caused by SARS-CoV-2 infection and most approaches thus far have evaluated sensory training and regimen-based treatment strategies independently. In this retrospective case series, we demonstrate the effectiveness of a comprehensive, combined treatment protocol for COVID-19-induced taste and smell dysfunction using olfactory and gustatory training in combination with vitamins and supplements, nasal irrigations, nerve stimulation exercises, and anti-inflammatory prophylaxis. Acutely infected patients with COVID-19-related loss of taste and smell were given a daily regimen of zinc, vitamin A, B-complex, vitamin D, and alpha lipoic acid in addition to saline nasal irrigation, fluticasone spray, nerve stimulation exercises, and repeated olfactory-gustatory training. Triamcinalone paste, theophylline, and prednisone were included daily with the observation of partial recovery. At two timepoints over approximately 20–37 days of treatment, taste and smell scores were quantified based on detection of agents included on each sensory training panel. Following this novel and comprehensive “Training ‘N’ Treatment” (TNT) protocol, every patient exhibited a complete recovery of taste and smell. Given the potential to provide relief to the many people with olfactory and gustatory dysfunction following SARS-CoV-2 infection, the effectiveness of this protocol warrants validation in a larger study.

Long-term Consequences of COVID-19: Chemosensory Disorders.

PURPOSE OF REVIEW: A number of sequelae after acute coronavirus disease 2019 (COVID-19) significantly affect the quality of life of patients. The chemosensory disorders including olfactory dysfunction (OD) and gustatory dysfunction (GD) are two of the commonest symptoms complained by patients with COVID-19. Although chemosensory function has been reported improved in over 60% of COVID-19 patients in a short time after acute infection, it may last as a major symptom for patients with long COVID-19. This narrative review discussed current literatures on OD and GD in long COVID-19 including the prevalence, risk factors, possible mechanisms, and potential therapies. RECENT FINDINGS: Although the prevalence of OD and GD has declined continuously after acute COVID-19, a considerable number of patients had persistent chemosensory disorders 3 months to 2 years after symptom onset. Female gender, initial severity of dysfunction, nasal congestion, emotional distress and depression, and SARS-CoV-2 variants have been identified as risk factors for persistent OD and GD in long COVID-19. The pathogenesis of OD and GD in long COVID-19 remains unknown, but may be analogous to the persistent OD and GD post common respiratory viral infection. Corticosteroids and olfactory training might be a potential choice regarding the treatment of lasting OD and GD after SARS-CoV-2 infection; however, more studies are needed to prove it. OD and GD are common long-term consequences of COVID-19 and influenced by gender, initial severity of dysfunction, emotional distress and depression, and SARS-CoV-2 variants. More studies are needed to illustrate their pathogenesis and to establish therapeutic strategies.