Meningococcal Infection in Novosibirsk: Changes in Epidemiology and Prevention Problems

Abstract

Relevance. Meningococcal disease is a relatively rare but still potentially fatal and disabling infection, affecting primarily healthy people of all age groups, and remains an important public health problem.Aims. The aim of the study was to analyze the long-term dynamics of the incidence of MI in the Novosibirsk region (NSO; identification and study of the factors that determined the change in the incidence of MI in 2019 in the region.Materials & Methods. A retrospective comparative epidemiological analysis of the incidence of the population of the Novosibirsk region in 1992–2019 was carried out. using statistical reporting forms No. 2 «Information on infectious and parasitic diseases»; state reports «On the state of sanitary and epidemiological well-being ofthe population oftheRussian Federation» for 1998–2015, and according to the NSO for 2005–2019.Results. An analysis of the epidemiological patterns of MI in the NSO revealed the presence of significant fluctuations in the incidence rates with multiple replacements of the leading strains of meningococcus, in the absence of immunity to all the main pathogens of MI in the vast majority of the region's inhabitants (from 60% to 82.92% of the population in different years remained seronegative to meningococcus serogroup A, 100% of the examined are seronegative to serogroup C). Simultaneously with the change in the epidemic situation in MI in the NSO in 2019, a tendency towards an increase in the incidence of MI was registered during 2016–2019 and in all regions ofCentral Asia, from where the influx oflabor migrants with their families continues. As anti-epidemic measures in risk groups, vaccination was used mainly against meningococcus serogroup A in combination with chemoprophylaxis in contact persons.Conclusion. The NSO (Novosibirsk) is characterized by: dynamic changes in the circulating serogroups of meningococcus, the presence of refugees and migrants with a high risk of infection with local strains and the introduction of new ones, including hypervirulent strains from regions on the transit route; high risk of repeated outbreaks and further complication of the epidemic situation. It is necessary to form a regional vaccine prophylaxis program, taking into account the variability of the etiology of MI and the most effective prevention strategies.