What correlations exist between olfactory dysfunction (OD) severity and duration and the viral load on the rhino-pharyngeal swab in direct testing in patients affected by COVID-19?
Explore This IssueOctober 2021
OD presence does not seem to be useful in identifying subjects at risk for being super spreaders and is most likely related to individual factors rather than to viral load and activity.
BACKGROUND: A majority of patients with COVID-19 complain of OD. Although initially attributed to phenomena of neuroinvasion, researchers are now focused on the olfactory epithelium as the site of viral damage underlying OD. To date, neither the pathogenesis nor the development of OD in COVID-19 patients has been identified.
STUDY DESIGN: Prospective cohort study.
SETTING: Department of Medical, Surgical and Experimental Sciences, University of Sassari, Sassari, Italy.
SYNOPSIS: Researchers enrolled 60 adult patients, all of whom had been admitted to a single hospital with a rhino-pharyngeal swab positive for SARS-CoV-2 infection and COVID-19 present for fewer than 10 days, and a control group of 30 subjects who had no history of previous SARS-CoV-2 infection and whose nasopharyngeal swab was negative. All patients underwent psychophysical olfactory assessment with the Connecticut Chemosensory Clinical Research Center test and determination of the normalized viral load on nasopharyngeal swab. On testing, the overall median olfactory score in the study group was 50 (interquartile range 30-72.5), with no significant differences between clinical severity subgroups. Neither the olfactory scores nor the viral load showed any correlation with COVID-19 severity. Among the control group, only five patients had OD on the test, and the overall median score was 100. Correlation between viral load and olfactory scores at baseline and 60-day control was weak and not significant. Study limitations included the limited number of patients and the monocentric setting.
CITATION: Vaira LA, Deiana G, Lechien JR, et al. Correlations between olfactory psychophysical scores and SARS-CoV-2 viral load in COVID-19 patients. Laryngoscope. 2021;131:2312-2318.