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.

Dataset on assessing olfactory function in the residents of Central Russia using the University of Pennsylvania Smell Identification Test.

Data were acquired via sensory testing of olfactory function in 252 adult residents of Central Russia (18-87 years old), including groups from urban and rural areas. The 40-item North American version of the University of Pennsylvania Smell Identification Test (UPSIT) was used. The test alternatives were initially translated into Russian by the authors with minor adaptations. We followed the test procedure recommended by the manufacturer and introduced additional tasks. Familiarity with odor names and consistency with the pre-existing concepts for the test odor items were determined using multiple response questions. Intensity ratings for the UPSIT odorants were obtained using 4-point categorical scale for a subset of the participants. Demographic data and other relevant characteristics of the study population were collected using an adapted translation of the questionnaire included with the test. Descriptive statistics of the collected data are presented in this article. The dataset may be reused for evaluating the impact of various factors, such as cultural context, age, sex, environment, and smoking habits, on the perception of specific odorants as well as on general olfactory function (determined by the number of recognized test items). The data may find its application in the clinical practice of otolaryngologists and neurologists who work with the ethno-cultural group in Russia and all over the world. The dataset can also be used for development of new diagnostic tools for olfactory dysfunction.

Possible roles of phytochemicals with bioactive properties in the prevention of and recovery from COVID-19.

Introduction: There have been large geographical differences in the infection and death rates of COVID-19. Foods and beverages containing high amounts of phytochemicals with bioactive properties were suggested to prevent contracting and to facilitate recovery from COVID-19. The goal of our study was to determine the correlation of the type of foods/beverages people consumed and the risk reduction of contracting COVID-19 and the recovery from COVID-19. Methods: We developed an online survey that asked the participants whether they contracted COVID-19, their symptoms, time to recover, and their frequency of eating various types of foods/beverages. The survey was developed in 10 different languages. Results: The participants who did not contract COVID-19 consumed vegetables, herbs/spices, and fermented foods/beverages significantly more than the participants who contracted COVID-19. Among the six countries (India/Iran/Italy/Japan/Russia/Spain) with over 100 participants and high correspondence between the location of the participants and the language of the survey, in India and Japan the people who contracted COVID-19 showed significantly shorter recovery time, and greater daily intake of vegetables, herbs/spices, and fermented foods/beverages was associated with faster recovery. Conclusions: Our results suggest that phytochemical compounds included in the vegetables may have contributed in not only preventing contraction of COVID-19, but also accelerating their recovery.

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.

Olfactory perception of 5α-androst-16-en-3-one: Data obtained in the residents of central Russia.

This dataset describes olfactory perception of androstenone (5α-androst-16-en-3-one) in residents of central Russia (n=807, 9-84 years old). Based on previous studies, 3.13 × 10-3% androstenone was utilized for sensory testing. A modified two-alternative choice task with "no-difference" options was applied as an odor discrimination procedure. The participants rated the perceived odor intensity and pleasantness on 3-point categorical scales. The subsequent task was free odor identification. We used a survey to determine characteristics of our study population such as age, sex, ethnicity, olfactory abilities, smoking habits, respiratory tract diseases, perfume use, blood group. To examine sex differences in characteristics of participants, as well as in their perception of androstenone, we have applied one-way ANOVA for age variable and Chi-square tests for categorical variables. The dataset will be useful for assessing the impact of the aforementioned factors on the perception of volatile steroids. A wide range of researchers studying verbal descriptors of specific odors and cross-cultural differences in olfactory perception may reuse this dataset. Primarily, this dataset may benefit meat industry, as androstenone, which is perceived as an unpleasant odor by about a quarter of the population, significantly contributes to pork flavor.