Аnti-HBs levels in health care workers vaccinated against hepatitis B

Along with patients, medical personnel are a risk group for the incidence of healthcare-associated infections (HCAI), which determine the effect of the biological production factor on the body of workers. Among the risks of infection, the first place is occupied by the risk of infection with viral hepatitis B (HBV), which belongs to vaccine-preventable infections. The level of аnti-HBs in medical workers, which appears in the serum of the immunized, is an indicator of the degree of their protection from this infection. The objective of the study was to assess the effect of age and timing of the last dose of hepatitis B vaccine during primary vaccination of health care workers on the level of аnti-HBs, which characterizes the degree of postvaccine immunity. Materials and methods. A retrospective epidemiological study of postvaccine immunity of 1,597 medical workers (doctors, nurses, nurses) of three multidisciplinary medical institutions who were initially vaccinated at different time intervals (from 3 months to 23 years) was performed. The study for HBs was carried out using the immunoenzyme test system ‘Vectohep B – HBs-antigen-strip’. Microsoft Office Excel 2010 and Prism9 software (GraphPad, USA) were used in the statistical analysis. Results. It was shown that 41.9% to 49.4% of HBV vaccinated individuals had humoral immunity below protective values (аnti-HBs <10 mIU/mL) regardless of the time frame (1 to 23 years) elapsed from immunization. Protective levels of аnti-HBs were maintained after 5 years of immunization by 58.1% of those vaccinated, and 50.5% of those vaccinated for 6 or more years. The age of health care workers had no noticeable effect on seroconversion. Conclusion. The proportion of individuals with absence of protective levels of аnti-HBs in serum is almost identical in individuals immunized between 3 months and 5 years, 6 to 15 and 16 to 23 years and is approximately 49% of the vaccinated population. Monitoring of the level of postvaccinal immunity to hepatitis B virus allows to identify the group of persons with lack of immunoconversion after immunization and to solve the issue of additional booster dose of the drug. Key words: medical workers, viral hepatitis B, immunity intensity, postvaccinal immunity, аnti-HBs