EFFECT OF COVID-19 DISEASE IN SMELL AND TASTE OF PATIENTS WITH MILD, MODERATE OR SEVERE SYMPTOMATOLOGY

Eligible participants who will be recruited in this research protocol will be adult patients
who are diagnosed positive for SARS-COV2, infection with Real Time Polymerase Chain Reaction
Test (RT-PCR).

The study population will be divided in two groups. The first group will be consisted with
positive patients that were referred to either the Emergency Department (ED) of Infectious
Diseases or at the Outpatient Clinic screening for SARS-COV2 and are being self-quarantined
at home. The participants will be hospitalized patients in the Infectious Diseases Unit (IDU)
of the University General Hospital of Ioannina.

The examination will be performed at the moment of diagnosis both for self-quarantine
patients and for in hospitalized patients. The follow up evaluation will be a re-examination,
performed at least four weeks after the moment of diagnosis. The time internal of reassessing
the patients chosen according to current literature, estimated that is the minimum
reassessment interval and seems to be a reference time for either progression stabilization
or recession of the symptoms of anosmia/ ageusia (12, 13).

Patients will be asked to evaluate their olfactory and gustatory abilities through the visual
analogue scale (VAS), at three time points: 1.before infection( as they can recall it), 2. at
the time of diagnosis and 3. four weeks later(14).

Patients' scoring will be recorded in a horizontal presentation of 100 VAS points, where zero
refers to no smell or taste while 100 refers to normal sensation. In addition, patients will
rate their nasal obstruction and rhinorrhea on a similar VAS scale, where 0 refers to a
completely blocked nose and an excessively runny nose while 100 indicates normal nasal
breathing and a no runny nose. All patients will assess the intensity of the olfactory and
taste function, through a self testing them at home. Patients will rate from 0 to 100 the
intensity of smell, after being exposed to five common household odors (ie lemon juice,
oregano, instant coffee, toothpaste and mint gum).The choice of these substances is based on
their influence at the irritation of the trigeminal nerve.

The intensity of taste function will be evaluated using four(4) substances: sugar, salt,
lemon juice and instant coffee (decaffeinated), that represent the following 4 basic quality
flavors:sweet, salty, sour and bitter. Every patient will have to receive orally half a
teaspoon of each testant and report the quality of taste perception. After each testant they
have to rinse their mouth with tap water. Bitter testant will have to be tested in the end.

Patient demographics, associated symptoms, and comorbidities will be recorded. The patients
will have to report and fill in symptoms such as fever, cough, shortness of breath or
dyspnea, fatigue, muscle aches, runny nose, blocked nose, loss of smell, and loss of taste.

The results will be recorded in a questionnaire.

Covid-19 positive patients recovering at home, will be informed for the study either by
telephone or in person, following all the safety measures provided by National Organization
of Public Health of Greece, by one of the investigators officially participating in the
study. A questionnaire will be completed by the examinee, after telephone information about
the purpose of the study and after providing a written consent from.

In hospitalized patients in the Infectious Diseases Unit, will be informed by the
investigators participating in the study and will follow the above procedure.

This study was submitted for approval to the research ethic committee and the scientific
council of University General Hospital of Ioannina and was accepted.