Limited Impact of Adolescent Meningococcal ACWY Vaccination on Neisseria Meningitidis Serogroup W Carriage in University Students

摘要: Background In the UK rising disease levels due to Neisseria meningitidis serogroup W clonal complex ST-11 (MenW:cc11) strains led introduction of conjugate MenACWY vaccination for teenagers. We investigated impact immunization on carriage targeted meningococci by whole genome sequencing isolates recovered from a cohort vaccinated university students. Methods Strain designation data were extracted sequence data. Genomes carried and invasive MenW:cc11 compared using gene-by-gene approach. Serogrouping identified expressing capsule antigens vaccine. Results Isolates with W: P1.5,2: F1-1: (cc11) designation, belonging emerging ‘2013-strain’ South American-UK sub-lineage, responsible an increase in group W. A multifocal expansion was evident close transmission networks extending beyond individual dormitories. Carried Y predominantly 23, but showed significant heterogeneity strain designations only sporadically recovered. No shifts towards acapsulate phenotypes detected meningococcal populations. Conclusions In setting high vaccination, capsule-expressing 2013-strain MenW:cc11, not MenY:cc23 isolates, is indicative differential susceptibilities vaccine-induced immunity.