The effect of vaccination against the COVID-19 on the course and outcomes of a new coronavirus infection: a retrospective analysis of laboratory and clinical indicators of hospitalized patients

Aims: to assess the effect of vaccination against the COVID-19 on the severity of the current and the outcome of a new coronavirus infection in hospitalized patients during the dominance of the SARS-CoV-2 Omicron. Materials and methods: study of the type of case-control included adult patients hospitalized in the infectious hospital of Moscow from February 1, 2022 to July 31, 2022 with a diagnosis of COVID-19 (U07.1) (N = 119). The main group included persons vaccinated with 2 doses of the Sputnik V vaccine (n = 59). Unvaccinated patients were included in the control group (n = 60). The median age of patients amounted to 66 years [IQR: 41-66], 58.8% were female. Chi square test for categorical and Mann Whitney test for continuous variables were applied for the analysis. P values 0,05 were considered statistically significant. Results: viral pneumonia was less likely to develop in vaccinated persons compared to unvaccinated persons (46.7% and 18.6%, respectively, p=0.007). The share of patients without lung damage (KT-0) among vaccinated (72.0%) was significantly higher than that of unvaccinated patients (42.9%) (p=0.003). In the group of vaccinated the levels of C-reactive protein, when entering the hospital was lower (29.1 [7.4-68, 6] mg/L and 75.1 [32.4-104.0] mg/L, p0.001), as the highest level of C-reactive protein during hospitalization (38.2 [12.0-84.0] mg/L and 92.2 [45.3-137.4] mg/L, p0.001). The level of D-dimer before discharge was lower in group of patients vaccinated ≤6 months ago compared with unvaccinated (157.0 [107.0-297.0] ng/ml and 316.0 [125.0-556.0] ng/ml, p=0.014). The frequency of deaths in the control group (11.7%) was 6.9 times higher compared to the main group (1.7%) (p=0.030). Conclusions: the completed primary vaccination course of the Sputnik V vaccine provided lower levels of prognostic markers of the adverse course of COVID-19 (C-reactive protein, D-dimer), as well as a decrease in the frequency of pulmonary and fatal outcome compared to unvaccinated patients during the dominance of the Omicron SARS-CoV-2.