Assessment of Long-Term Taste and Smell Color Blindness as a Result of Covid-19 Disease

Abstract

Among the effects of COVID-19 are taste and smell disorders, which have occurred in a significant number of sick people. It is believed that the impairment of these senses may be long term. The aim of our research was to investigate the impact of COVID-19 disease on the ability to recognize tastes among students at the Rzeszów University of Technology. The research was conducted on a sample of students who declared that they had or had not suffered from COVID-19. The assessment of the ability to recognize flavors – that is, taste color blindness – was carried out based on the methodology recommended by the Polish Committee for Standardization [PN ISO3972]. The research, which involved 68 women and 74 men, was carried out in a laboratory adapted for this purpose, meeting the requirements specified in the standard [PN ISO 8589]. The tests took place in the morning (9 a.m.–12 p.m.). Taste recognition ability was assessed using a set of aqueous solutions of citric acid (0.43 g/L), sucrose (5.76 g/L), sodium chloride (1.19 g/L) and caffeine (0.195 g/L). The collected questionnaires were based on a standard approach to food quality analysis, and the data obtained were analyzed in the Statistica 13.3 program. It was observed that, in the studied group of students, the percentage of people who declared COVID-19 disease was high (69%). In this group, the majority of respondents (51%) described the course of the disease as mild. Among the respondents, 63.3% indicated a loss of taste, while slightly more (69.4%) declared a loss of smell. The analysis of data regarding the ability to correctly recognize individual tastes indicates that gender influenced the ability to recognize sweet and bitter tastes. Statistically, significantly more men misidentified these flavors. The impact of COVID-19 infection on the ability to identify the analyzed flavors was moderate and was confirmed only for salty and bitter tastes. Therefore, the ability to perceive important qualitative factors of food products was impaired.