Diversity of greek meningococcal serogroup B isolates and estimated coverage of the 4CMenB meningococcal vaccine
1 National Meningitis Reference Laboratory, National School of Public Health Athens, 196, Alexandras Avenue, Athens, Greece
2 Institute Pasteur, Invasive Bacterial Infections Unit, Paris, France
3 Novartis Vaccines and Diagnostics, Siena, Italy
BMC Microbiology 2014, 14:111 doi:10.1186/1471-2180-14-111Published: 29 April 2014
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).
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.
4CMenB has the potential to protect against a significant proportion of Greek invasive MenB strains.