Assessment of Seroconversion to SARS-CoV-2 in Health Care Unitunit Personnel

Relevance. The novel coronavirus pandemic is a major burden on public health and healthcare professionals. The study of the prevalence of antibodies among medical workers provides an understanding of the potential risk of transmission of the infectious agent, the level of herd immunity, the introduction of specific immunization and risk stratification in various areas of professional activities.

The purpose of this study was to assess the level of specific antibodies to SARS-CoV-2 in the personnel of the medical and sanitary unit, providing the population with outpatient and inpatient medical care.

Materials and methods. A study to assess seroprevalence to the SARS-CoV-2 virus was carried out in the Omsk region from September 2020 to December 2020. The study included 2 groups of employees of continuously operating organizations – the main group – employees of the medical and sanitary unit of the city of Omsk (n = 631), the control group consisted of employees of two industrial enterprises in the city of Omsk (n = 1696). The level of class G immunoglobulins to the SARS-CoV-2 virus was determined by enzyme-linked immunosorbent assay.

Results. Among medical workers, the proportion of people with a positive reaction to IgG was 73.1% (n = 461; 95% CI 69.5–76.4%). In the control group, the proportion of those who were seropositive was 3.9 times less than that – 18.6% (n = 315; 95% CI 16.8–20.5). Significant differences in seroprevalence in men and women were revealed in medical workers (χ2 = 4.164; p = 0.0413). The highest proportion of seroconversion was found in nursing staff – 85,4% (95% CI 71.6 – 93.1), in doctors – 63.3% (95% CI 55.0–70.9). The highest rate of seroprevalence was found among hospital medical workers – 81.9%, the lowest among employees of the administrative and economic service – 51,8%.

Conclusions. The level of specific antibodies to SARS-CoV-2 among medical workers significantly exceeded that of other professional groups, and there was a high proportion of seroconversion among junior medical personnel and in-patient medical unit workers.

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