World Experience in the Use Serogroup B Meningococcal Vaccines (literature review)

Relevance. The success of vaccine prophylaxis of meningococcal infection depends on the composition and properties of vaccine preparations and the strict implementation of recommendations on vaccine prophylaxis tactics by the territorial epidemiological characteristics of meningococcal infection. Despite the high burden of B-meningococcal infection, especially among young children, the design of B-meningococcal vaccines has faced serious difficulties. Aim. The literature review presents the history of the development of B-meningococcal vaccines and provides characteristics of two immunologically effective and safe new generation B-meningococcal vaccine preparations. Conclusion. The licensing of the two new B-meningococcal vaccines presented in the review (Bexsero and Trumenba) was based on immunogenicity and safety. The inclusion of vaccines in national vaccination programs requires careful analysis, including analysis of the antigenic characteristics of circulating strains.

Hospitalizations related to meningococcal infection in Spain from 1997 to 2018

Background Baseline hospitalization, mortality, and in-hospital fatality rates for meningococcal infection are required to evaluate preventive interventions, such as the inclusion of the conjugated quadrivalent meningococcal vaccine and serogroup B based protein vaccines. Methods All meningococcal infection–related hospitalizations in any diagnostic position in Spain from 1st January 1997 through 31st December 2018 were analysed. The annual hospitalization rate, mortality rate and case-fatality rate were calculated. Results The average hospitalization rate for meningococcal infection was 1.64 (95% CI 1.61 to 1.66) hospitalizations per 100,000 inhabitants during the study period and significantly decreased from 1997 to 2018. Hospitalizations for meningococcal infection decreased significantly with age and were concentrated in children under 5 years of age (46%). The hospitalization rates reached 29 per 100,000 and 24 per 100,000 children under 1 and 2 years of age, respectively. The in-hospital case-fatality rate was 7.45% (95% CI 7.03 to 7.86). Thirty percent of the deaths occurred in children under 5 years of age, and more than half occurred in adults. The case fatality rate increased significantly with age (p < 0.001). Conclusion It is necessary to maintain epidemiological surveillance of meningococcal infection to determine the main circulating serogroups involved, track their evolution, and evaluate preventive measures whose effectiveness must be assessed in all age groups.

Evaluation of urethrotropic clade meningococcal infection by urine metagenomic shotgun sequencing.

Background Urethral infections caused by an emerging nongroupable (NG) urethrotropic clade of Neisseria meningitidis (Nm) were first reported in the United States in 2015 (the “U.S. NmNG urethritis clade”). Here we evaluate for the presence of other urethral pathogens in men with U.S. NmNG urethritis clade infection. Methods: We evaluated 129 urine specimens collected from men at a sexual health clinic, including 33 from patients with culture-confirmed or suspected urethral Nm infection and 96 specimens in which nucleic acid amplification test detected Neisseria gonorrhoeae (Ng), Chlamydia trachomatis (Ct), both pathogens, or neither pathogen. Nm was detected first by real-time PCR, followed by metagenomic shotgun sequencing of 91 specimens to identify coinfections. Nm genomes were sequenced following selective whole genome amplification when possible. Results: Metagenomic sequencing detected Nm in 16 of 17 specimens from culture-confirmed Nm cases, with no coinfection by other conventional urethral pathogens. Metagenomic sequencing also detected Nm in three Ct positive specimens, one specimen positive for both Ng and Ct, and nine specimens with negative Ng and Ct results, eight of which had suspected Neisseria infections. Nm from culture-confirmed Nm cases belonged to the U.S. NmNG urethritis clade, while Nm identified in other specimens belonged to multiple clonal complexes. Additional urethral pathogens were predominant in non-Nm specimens, including Ng, Ct, Mycoplasma genitalium , Ureaplasma urealyticum , and herpes simplex virus type-2. Conclusions: Coinfection with other conventional urethral pathogens is rare in men with culture-confirmed U.S. NmNG urethritis clade infection and points to the strong association of this clade with disease.

Clinical and epidemiological characteristics of meningococcal infection morbidity in Penza Region for the period 2007-2019

Objective. To study the clinical and epidemiological characteristics of meningococcal disease morbidity in the Penza Region population for the period 2007-2019.Materials and methods. The retrospective analysis carried out of archival documents of a specialized infectious diseases hospital in Penza and materials of the center of the Federal Service for Supervision of Consumer Rights Protection and Human Well-being. Methods of statistical processing were used for the analysis.Results and discussion. As a result of the analysis, it was revealed that the incidence of meningococcal infection in the Penza region exceeds the average level in Russia for almost the entire time period under study. We revealed the predominance of the share of the child population in the structure of total morbidity throughout the entire time tranche under study was revealed. The presence of 4 peaks in the mortality rate was found — in 2009, 2012, 2014 and 2016. On the territory of the Penza region, the infection has a pronounced winter-spring seasonality, there are generalized forms of meningococcal infection and localized forms of meningococcal infection.Conclusions. Thus, meningococci of serogroups B and C prevail in the serogroup landscape of meningococci in the Penza region. The excess of the average Russian indicators of the incidence of meningococcal infection was revealed by 2 or more times throughout the entire study period. patients under the age of 14 from unorganized groups predominate among patients with meningococcal infection. the Gender structure is dominated by males from rural areas. The infection has a pronounced winter-spring seasonality. The most common clinical forms are meningitis and mixed form.

The Emergence of a Ciprofloxacin-Resistant Non-Groupable Neisseria meningitidis Strain of the Clonal Complex ST-175 in the Russian Federation

Relevance. Unencapsulated strains of meningococcus (NmNG) very rarely cause invasive meningococcal disease. A new ciprofloxacin-resistant strain NmNG ST-175 cc175, which has recently caused several cases of invasive meningococcal infection in Europe, has been discovered in the Russian Federation.Aim. To compare the new Russian strains of NmNG ST-175 with the already characterized NmNG ST-175 and to analyze the genetic markers associated with antibiotic resistance.Materials and methods. The nucleotide sequences of NmNG ST-175 strains of more than 2 million base pairs were exported from the PubMLST database. Comparison was carried out for 1605 core genome loci using the N. meningitidis cgMLST v1.0 ". Genetic relationships of 127 NmNG ST-175 strains, including 8 Russian carrier strains, were visualized using the SplitsTree software (version 4.16.2).Results. Of the eight Russian strains, six found themselves in a cluster with German and Swedish isolates that caused invasive meningococcal infection. Two more Russian strains were closest to the isolates of the cluster, including carrier isolates from England. Seven strains showed resistance to ciprofloxacin and possessed the gyrA-187 and gyrA-152 alleles, which, based on the phylogenetic analysis of the alleles, belonged to the genetic branches of Neisseria cinerea and Nm.Conclusion. Protein vaccines alone could potentially provide protection against ST-175 NmNG. It seems promising to study the antigenic characteristics of Russian Nm strains, including NmNG ST-175, to assess the potential vaccination coverage with existing protein vaccines, the possibility of their registration on the territory of the Russian Federation, as well as the development of domestic vaccines.

Improving the therapy of generalized forms of Meningococcal infection in children using extracorporeal hemocorrection

Invasive meningococcal infection is a significant cause of death, reaching 80% in septic shock. The Pediatric Research and Clinical Center for Infectious Diseases (PRCCID) has developed an algorithm for the treatment of children with invasive meningococcal infection with refractory septic shock and multiple organ failure syndrome, which includes basic drug therapy with polymyxin hemoperfusion in combination with extended methods of extracorporeal hemocorrection.Purpose: to evaluate the effectiveness of extracorporeal hemocorrection operations in children with invasive meningococcal infection with refractory septic shock and multiple organ failure syndrome.Materials and research methods: to the intensive care unit of the PRCCID for the analyzed period 2006—2020 34 children were hospitalized with invasive meningococcal infection with refractory septic shock and multiple organ failure syndrome. Two groups were formed: Group 1 — children admitted to the PRCCID in the period 2014—2020 (n = 23), who underwent polymyxin hemoperfusion simultaneously with extended methods of extracorporeal hemocorrection, group 2 — children hospitalized in 2006—201 3 (n = 1 1), methods of extracorporeal hemocorrection were not performed. The Mann-Whitney U-test and ANOVA were used to evaluate the results.Results and discussion: the use of extracorporeal hemocorrection operations in the complex therapy of invasive forms of meningococcal infection with refractory septic shock and multiple organ failure syndrome in children provides stabilization of central hemodynamics, reduces clinical and laboratory inflammatory reactions, helps to reduce the dose of vasopressor drugs and parameters of respiratory support, and also increases patient survival rate by 82.6%.