In a study published in “JAMA Network Open,” one in two patients with CoVid A variant still had smell disturbances after one year, which also explained the taste disturbances.
After Omicron infection, disorders were slightly more frequent than in a control group without SARS-CoV-2.
Disturbances of smell and taste are the most common long-term symptoms of CoVid, which many patients continue to complain of for months to years after infection.
However, to date only a few studies have been conducted in which the two sensory perceptions have been objectively analyzed and the results compared with healthy volunteers.
A team led by Dr. Shima Moein of the Perelman School of Medicine in Philadelphia examined 340 patients an average of 395 days after contracting CoVid and compared the results with 434 healthy individuals.
Taste was tested using the Waterless Empirical Taste Test (WETT), which the patients performed themselves at home.
The test consists of 53 test strips with different concentrations of sucrose, citric acid, sodium chloride, caffeine and monosodium glutamate for the five known taste sensations, as well as neutral sticks. Test participants had to write down on a card what they had tasted and tasted.
The sense of smell was tested using the “University of Pennsylvania Odor Identification Test” (UPSIT), which contains 40 different odors. Patients were infected with the original wild type or the following Alpha, Delta or Omicron variants.
Result: In the WETT trials, all ex-CoViD-19 patients achieved comparable results to the control group after one year. This confirms the hypothesis that the taste disturbances complained of by many patients are ultimately olfactory disturbances.
They can be explained by the damage of the olfactory epithelium caused by SARS-CoV-2 infection. According to current knowledge, the taste buds in the tongue are not affected by SARS-CoV-2. However, many people cannot tell the difference between the smell and taste of food.
In the smell test, however, there were failures that were still detectable even after a year. Of the patients infected with the wild type, 13.5% achieved a UPSIT score of 6 to 25 points, indicating severe or complete loss of smell.
After infection with the Alpha variant, the rate was 23.8%, double that. After infection with the Delta variant, it was 6.2% and after infection with the Omicron variant, 4.7% compared to 2.8% in the control group.
Therefore, infection with the Alpha variant resulted in the most severe olfactory impairment, followed by the wild-type virus. According to Moein, the differences between the Delta variant or the Omicron variant and the control group were not significant.
Therefore, people currently infected with SARS-CoV-2 have a good chance of not being affected by this key symptom of Long – CoVid.
