Epidemiological Features of Purulent Bacterial Meningitis in the Russian Federation at the Present Stage

Relevance. The decrease in the number of cases of invasive diseases caused by N. meningitidis, S. pneumoniae, H. influenzae and in the world has been associated with measures against the spread of the 2019 coronavirus disease (COVID-19). Aim. Presentation of the epidemiological features of purulent bacterial meningitis (PBM) in the Russian Federation at the present stage. Materials and methods. On the basis of the Russian Reference Center for Monitoring Bacterial Meningitis (RCMC), an in-depth personalized system for recording PBM cases has been established. Since 2010, all territories of the Russian Federation have been included in the monitoring system. In 2022, the RCMC received information on 1596 cases of PBM. The descriptive-evaluative epidemiological method was used in the work: a retrospective analysis. Results. The increase in the incidence of a generalized form of meningococcal infection (GFMI), which began in 2017, was recorded in 2018 and 2019, but in 2020–2021 growth was interrupted: the indicator dropped sharply, amounting to 0.26–0.21 per 100 thousand of the population, which is most likely due to the disunity of the population as a result of measures aimed at combating the new coronavirus infection. Measures to combat COVID-19 were canceled in 2021, and already in 2022 the incidence rate of GBM increased by 1.4 times, while the GFMI by 2 times, amounting to 0.44 per 100 thousand of the population. A sharp decrease in the incidence of PBM caused by S. pneumoniae and H. influenzae in 2020-2021 was replaced in 2022 by an increase in the incidence of pneumococcal meningitis, however, the incidence of meningitis caused by H. influenzae remained at the same level. Conclusion. Continued monitoring of the incidence of PBM and the properties of the pathogen are extremely important tasks in order to identify risk groups and areas for the timely optimization of vaccination measures, given that the three infections that cause bacterial meningitis are vaccine-controlled, and vaccination is recognized as the most effective measure to combat meningococcal, pneumococcal and hemophilic infections.