Meningococcal B vaccine antigen FHbp variants among disease-causing Neisseria meningitidis B isolates, Italy, 2014-2017

• Published in: PloS one 2020-11, Vol.15 (11), p.e0241793-e0241793
• Main Authors: Carannante, Anna, Fazio, Cecilia, Neri, Arianna, Lista, Florigio, Fillo, Silvia, Ciammaruconi, Andrea, Vacca, Paola, Stefanelli, Paola
• Format: Article
• Language: English
• Subjects: Antigens; Antigens, Bacterial - immunology; Antigens, Bacterial - metabolism; Bacterial Outer Membrane Proteins - immunology; Bacterial Outer Membrane Proteins - metabolism; Bacterial Proteins - immunology; Bacterial Proteins - metabolism; Bacterial Vaccines - immunology; Binding proteins; Biology and Life Sciences; Causes of; Culture; Deoxyribonucleic acid; DNA; Dosage and administration; Epidemiology; Factor H-binding protein; Forecasts and trends; Genetic diversity; Genetic Variation; Genomes; Health aspects; Health surveillance; Identification and classification; Immunization; Infectious diseases; Invasive meningococcal disease; Medicine and Health Sciences; Meningitis; Meningococcal disease; Meningococcal infections; Meningococcal vaccines; Meningococcal Vaccines - immunology; Meningococcal Vaccines - metabolism; Multilocus Sequence Typing; Neisseria meningitidis; Neisseria meningitidis, Serogroup B - immunology; Neisseria meningitidis, Serogroup B - metabolism; People and Places; Physiological aspects; Porins - immunology; Porins - metabolism; Public health; Software; Surveillance; Vaccines; Varieties; Whole Genome Sequencing
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0241793

Typing of Neisseria meningitidis isolates is crucial for the surveillance of invasive meningococcal disease (IMD). We performed a molecular epidemiology study of N. meningitidis serogroup B (MenB) causing IMD in Italy between 2014 and 2017 to describe circulating strains belonging to this serogroup, with particular regards to the two factor H-binding protein (FHbp) subfamilies present in the bivalent MenB vaccine. A total of 109 culture positive and 46 culture negative MenB samples were collected within the National Surveillance System (NSS) of IMD in Italy and molecularly analyzed by conventional methods. Overall, 71 MenB samples showed the FHbp subfamily A and 83 the subfamily B. The subfamily variants were differently distributed by age. The most frequent variants, A05 and B231, were associated with cc213 and cc162, respectively. All MenB with the FHbp A05 variant displayed the PorA P1.22,14 and 85.7% of them the FetA F5-5. The majority of MenB with the FHbp B231 variant showed the PorA P1.22,14 (65.4%) and 84.6%, the FetA F3-6. MenB circulating in Italy were characterized by a remarkable association between clonal complex and FHbp variants, although a high degree of genetic diversity observed over time. A dynamic trend in clonal complexes distribution within MenB was detected. Our results stress the importance of continued meningococcal molecular surveillance to evaluate the potential vaccine coverage of the available MenB vaccines.