Epidemiology of pathogenic Neisseria meningitidis serogroup B serosubtypes in Malta: implications for introducing PorA based vaccines.

Objective: To describe the epidemiology of the serosubtypes of Neisseria meningitidis serogroup B (MenB) in the most densely populated area in Europe and to review the MenB Porin A (PorA) based outer membrane vesicle (OMV) vaccines that could provide the broadest protection.

Study Design And Setting: Active surveillance of invasive meningococcal disease in a population of 400,000 inhabitants in Malta from 1999 to 2006. Serogroup B isolates were serosubtyped and analysed by age and year.