Isolation and characterization of Neisseria meningitidis in the vaccine era. Who needs what and when?

Diagnosing invasive meningococcal disease can require a number of different approaches. The logic behind and the practical steps for diagnosis are described and discussed. The characterization of Neisseria meningitidis can be performed with a number of methods, depending on the problem/question that is formulated. Increased availability and use of meningococcal vaccines with new immunizing proteins requires diagnostic and surveillance systems of high quality. It is foreseen that a combination of genetic characterization and proof of corresponding production/exposure of the protein by a phenotypic method will be an optimal strategy for dealing with candidate vaccine antigens that have genetic and phenotypic variability. Such an approach will make use of the best qualities of both systems. Who needs what and when concerning the characterization is outlined, including future situations when new meningococcal vaccines are available.