Diversity of Greek meningococcal serogroup B isolates and estimated coverage of the 4CMenB meningococcal vaccine.
BACKGROUND
Serogroup B meningococcal (MenB) isolates currently account for approximately 90% of invasive meningococcal disease (IMD) in Greece with ST-162 clonal complex predominating. The potential of a multicomponent meningococcal B vaccine (4CMenB) recently licensed in Europe was investigated in order to find whether the aforementioned vaccine will cover the MenB strains circulating in Greece. A panel of 148 serogroup B invasive meningococcal strains was characterized by multilocus sequence typing (MLST) and PorA subtyping. Vaccine components were typed by sequencing for factor H-binding protein (fHbp), Neisserial Heparin Binding Antigen (NHBA) and Neisseria adhesin A (NadA). Their expression was explored by Meningococcal Antigen Typing System (MATS).


RESULTS
Global strain coverage predicted by MATS was 89.2% (95% CI 63.5%-98.6%) with 44.6%, 38.5% and 6.1% of strains covered by one, two and three vaccine antigens respectively. NHBA was the antigen responsible for the highest coverage (78.4%), followed by fHbp (52.7%), PorA (8.1%) and NadA (0.7%). The coverage of the major genotypes did not differ significantly. The most prevalent MLST genotype was the ST-162 clonal complex , accounting for 44.6% of the strains in the panel and with a predicted coverage of 86.4%, mainly due to NHBA and fHbp.


CONCLUSIONS
4CMenB has the potential to protect against a significant proportion of Greek invasive MenB strains.
National Meningitis Reference Laboratory, National School of Public Health Athens, 196, Alexandras Avenue, Athens, Greece. gtzanakaki@esdy.edu.gr.
Georgina
G
Tzanakaki
Eva
E
Hong
Konstatinos
K
Kesanopoulos
Athanasia
A
Xirogianni
Stefania
S
Bambini
Luca
L
Orlandi
Maurizio
M
Comanducci
Alessandro
A
Muzzi
Muhamed-Kheir
MK
Taha
D000942:Antigens, Bacterial / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D014644:Genetic Variation; D006115:Greece / Q000453:epidemiology; D006801:Humans; D008589:Meningococcal Infections / Q000453:epidemiology* / Q000276:immunology / Q000382:microbiology*; D022401:Meningococcal Vaccines / Q000276:immunology*; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D038541:Neisseria meningitidis, Serogroup B / Q000145:classification* / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D012189:Retrospective Studies; D017422:Sequence Analysis, DNA
C570015:4CMenB vaccine; D000942:Antigens, Bacterial; D004269:DNA, Bacterial; D022401:Meningococcal Vaccines