Rising incidence of invasive meningococcal disease caused by Neisseria meningitidis serogroup W in Victoria.

The diagram illustrates the phylogenetic relationship between isolates based on core genome single nucleotide polymorphisms (SNPs). Victorian MenW ST11 isolates demonstrate region-specific clustering, and the close relationship of Victorian MenW strains (in green) to the United Kingdome South American cluster is shown. (Numerical values for the Victorian isolates represent the number of isolates, while the underlined description refers to geographical origin of isolates.) Note: Mixed Cluster 1 refers to isolates from the UK 1975e2007 and South Africa 2003e2013; Mixed Cluster 2 refers to isolates from UK 1996e2000, South Africa 2003e2004 and North Africa 1996e1999. u Imeningitidis is one of the most rapidly progressive sepsis syndromes, often resulting in significant morbidity and mortality. Since the introduction of meningococcal C conjugate vaccine in 2003, IMD in Victoria has decreased from 2.5/100 000 to 0.6/100 000 population. Epidemiological typing of N. meningitidis isolates is by serogroup, multilocus sequence typing and finetyping.