Dysosmia syndrome in COVID-19, сlinic, treatment and prevention

Background. Dysosmia is a group of various disorders of the olfactory analyzer, manifested by an increase or decrease in the ability to perceive odors, up to a complete loss of olfactory sensitivity. Until recently, the problem of olfactory impairment was not as urgent as it became in 2019 and 2020, when the whole world faced a pandemic caused by the SARS-CoV-2 virus. Such interest of doctors and researchers in olfactory dysfunction can be explained by the very high incidence of dysosmia associated with COVID-19 – 60-80% of the total number of cases among the European population and 30% among the population of East Asia. Most often olfactory function recovers spontaneously on the background of treatment of the underlying disease, usually within one month, and does not require additional therapeutic measures. As early as on day 8-9, up to 70% of patients notice an improvement in their sense of smell, and 80-90% of patients regain their sense of smell after two weeks. However, about 10-15% of patients have to turn to specialists for lack of sense of smell for 20 days or more. The presence of anosmia for more than 15-20 days is probably due to possible damage to olfactory receptor cells themselves, which can take up to 2 months to recover.

Conclusion. Since the olfactory function plays a large role in the life of every person, its loss can lead to discomfort, stress and limitation of various kinds of pleasures associated with the perception of smells, etc. In addition, the inability to distinguish odors can lead to poisoning with expired products or other harmful substances. Also, dysosmia associated with COVID-19 is of particular interest, since it has a specific neurosensory mechanism of occurrence associated with damage to the cells of the olfactory neuroepithelium. Therefore, it is necessary to develop an effective treatment plan for this complication of COVID-19 infection and conduct preventive education of the entire population.

1. Belopasov V. V., Yashu Ya. Nervous system damage in SOVID-19. Klinicheskaya praktika. 2020; 2 (11): 60-80. (In Russ.)

2. Gribok E. S., Borisevich A. A., Alexandrov D. A. Physiological basis of odour perception and types of olfactory impairment in SARS-CoV-2 infection. Student Medical Science of the XXI century: Proceedings of the XXIII International Scientific and Practical Conference of Students and Young Scientists. Vitebsk: VSMU, 2023.С. 882-886. (In Russ.)

3. Zaitseva O. V. Postviral dysosmia: therapeutic and diagnostic principles. Lechachaschiy Vrach. 2022; 4: 49-53. (In Russ.)

4. Krivopalov A. A., Dvoryanchikov V. V., Aleksanyan Yu. S. Dysosmia in polyposis rhinosinusitis and transferred coronavirus infection, actual issues of rehabilitation. Sovremennye problemy nauki i obrazovaniya. 2024; 1. URL: https://scienceeducation.ru/ru/article/view?id=33165 (Accessed: 18.01.2025). (In Russ.)

5. Malets E. L., Sivakov A. P., Alenikova O. A. Disturbances of olfaction and gustatory sensitivity associated with COVID-19. Otorinolaringologiya. Vostochnaya Evropa. 2020; 4 (10): 360-370. (In Russ.)

6. Hannum M. E., Ramirez V. A., Lipson S. J. Objective Sensory Testing ethods Reveal a Higher Prevalence of Olfactory Loss in COVID-19 – Positive Patients Compared to Subjective Methods: A Systematic Review and Meta-Analysis. Chem Senses. 2020; 45: 865-874.

7. Huang C. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. The Lancet. 2020; 10223 (395): 497-506.

8. Izquierdo-Dominguez A. Olfactory dysfunction in the COVID-19 outbreak. J Investig Allergol Clin Immunol. 2020; 5 (30): 317-326.

9. Kanjanaumporn J. Smell and taste dysfunction in patients with SARS-CoV-2 infection: A review of epidemiology, pathogenesis, prognosis, and treatment options. Asian Pacific Journal of Allergy and Immunology. 2020; 2 (38): 69-77.

10. Klopfenstein T. Features of anosmia in COVID-19. Medicine et maladies infectieuses. 2020; 5 (50): 436-439.

11. Lüers J. C., Klußmann J. P., Guntinas-Lichius O. Die COVID-19-pandemie und das HNO-Fachgebiet: Worauf kommt es aktuell an? (The Covid-19 pandemic and otolaryngology: what it comes down to?). Laryngorhinootologie. 2020; 5 (99): 287-291.

12. Moein S. T. Smell dysfunction: a biomarker for COVID-19. International forum of allergy & rhinology. 2020; 8 (10): 944-950.

13. Zaitseva O. V. Postviral dysosmia: therapeutic and diagnostic principles. Lechaschi Vrach. 2022; 4 (25):49-53.DOI: 10.51793/OS.2022.25.4.009. (In Russ.)

14. Instructions for medical use of the medicinal product ORVIS Rhino LP-#(006273)-(RG-RU)-180724. (In Russ.)

15. Acute sinusitis. CR 313. Approved by the Scientific and Practical Council of the Ministry of Health of the Russian Federation. М.: 2024. (In Russ.)