Background: the epidemiological situation with measles remains unstable, with periodic increases in morbidity. In the Russian Federation, as well as in other countries, cases of nosocomial infection continue to be registered. Medical workers may be involved in the epidemic process and serve, among other things, as a source of infection for patients. Aims: assessment of postvaccinal immunity to measles in medical workers in Kazan during its elimination period. Materials and methods: a cross-sectional study of immunity to measles was conducted in 515 employees of medical institutions in Kazan. 376 medical staff had documented ever-evidence of immunization against measles. Measles class G immunoglobulin levels were determined, specific immunity strength was assessed as a function of age, and time since the last vaccine dose was administered. Relative values (fractions, %) and standard error of the fraction (%) were calculated. A correlation analysis was performed. Results: The proportion of seropositive medical workers was 81% of all those examined. Those over 50 years of age were the most protected: antibodies were detected in 90.32,17% of them. Among the 417 persons with antibodies low level was detected in 60,9%, medium level - in 34,5%, high level - only in 4,6% of the examined persons. In all age groups the share of persons with low levels of protective antibodies was the highest. High level of protective antibodies was registered only in the age groups 40-49 years and 50 years and older (4,81,91% and 71,87%, respectively). Antibodies were detected in 78.2% of persons vaccinated against measles. Antibody levels correlated inversely with time since vaccination (p0.05). Conclusions: the results of serologic study of health workers demonstrate insufficient protection of health workers against measles, especially in younger groups. Decreased immunity in vaccinated health workers 10 or more years after immunization necessitates the monitoring of antibody levels in this group and consideration of revaccination.

Joint replacement is a reliable and effective surgery that allows profound pain relief and restores joint function in patients. Despite the progress made and the experience gained in joint replacement, surgical site infection is one of the leading postoperative complications. It can proceed as a periprosthetic joint infection, osteomyelitis, sepsis and lead to disabled or dead outcomes. Systematization of risk factors for infectious complications plays an important role as an element of epidemiological surveillance system optimization. Age, the presence of concomitant diseases (for example, diabetes mellitus, cancer, arthritis and systemic collagenosis), carriage of antimicrobial-resistant microorganisms, infectious and inflammation both outside and in the area of surgery, and external factors (surgery duration, correct antibiotic prophylaxis and surgeon's experience) are the most significant risk factors for periprosthetic joint infection. In world practice, the National Nosocomial Infections Surveillance System surgical site infection risk index is used. This criterion does not consider all potential risk factors. It is important to analyze and rank the identified risk factors according to the impact on the development of infectious complications in organizing an epidemiological surveillance system process in a medical organization. Risk factors analysis will identify the most significant modifiable factors for the development, implementation and execution of organizational, preventive measures and epidemic control. The creation and implementation of a standardized preoperative protocol based on a risk factors assessment will allow predicting the surgery outcome and arguing the strategy and tactic of preventive measures.