Clinical and laboratory features of coronavirus infection caused by the Omicron gene variant in outpatients

The objective is to study the clinical and laboratory features of a new coronavirus infection in outpatients during the circulation of the Omicron gene variant of SARS–COV-2.

Material and methods. The case histories of 100 outpatients (79 men, 21 women) aged 24 to 59 years with confirmed COVID-19 infection were retrospectively analyzed. The etiology of the disease was verified by the determination of SARS-CoV-2 RNA in nasopharyngeal samples by polymerase chain reaction (PCR). Statistical data analysis was carried out using the IBM SPSS Statistics 26 program. The Student and Pearson criteria were used in the calculations. Differences in indicators were considered statistically significant at p<0.05.

Results. In most outpatients, a new coronavirus infection occurred with a predominant lesion of the upper respiratory tract. At the onset of the disease, the characteristic clinical symptom in young patients was sore throat which was recorded twice as often as in middle-aged patients. An increase in temperature to subfebrile figures was recorded in 50% of cases. Cough syndrome was not typical for young patients. In 42% of patients, the level of acute-phase C-reactive protein was 1.2-1.5 times higher than the reference values.

Conclusion. COVID-19 infection caused by the Omicron gene variant in outpatients in most cases had a smooth course, and was characterized by a predominant lesion of the upper respiratory tract.

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