Post-Covid-19 Patients Follow-up Study

Olfactory (smell) function will be evaluated using the Twelve felt-tip Sniffin' Sticks test (Burghart Messtechnik GmbH, Holm, Germany). Participants are categorized into anosmic (score 0-6, no smell), hyposmic (score 7-10, reduced smell), and normosmic (score 11-12, normal smell), according to normative classification.

Gustatory (taste) function is assessed using Taste Strips impregnated with solutions of four different taste qualities (sweet, sour, salty, and bitter) in four different concentrations (Burghart Messtechnik GmbH, Holm, Germany). Participants are classified into ageusic (score 0, no taste), hypogeusic (score 1-8, reduced taste) and normogeusic (score 9-16, normal taste) using a normative classification. Participants are considered to have a specific ageusia if they are unable to detect all four different concentrations of a particular tastant.

Xerostomia (oral dryness) iss categorized according to participants' self-reported perception as either no dry mouth (score 0), or dry mouth (score 1). Participants are asked whether the symptoms of xerostomia started before or after COVID-19 infection and are asked open-ended questions where they could describe their experience of oral dryness. Finally, they are asked to report whether there are food items that they had to refrain from eating because of parosmia, dysgeusia, dysesthesia or xerostomia.

Dysesthesia (oral burning sensation) iss categorized as either no dysesthesia (score 0), or dysesthesia (score 1). Participants report how often they experienced dysesthesia (constantly, daily, sometimes, periodically, during meals, in between meals), asked to describe where in the mouth they experienced dysesthesia (whole tongue, anterior tongue, lips, palate, buccal mucosa, other), and identify food items that enhanced the dysesthesia (spicy, sweet, sour, salty, bitter).