Invasive serogroup W Neisseria meningitidis (MenW) in Ontario, Canada shows potential clonal replacement during the period January 1, 2009 – June 30, 2016

Abstract

Background: In Ontario, serogroup W Neisseria meningitidis (MenW) accounts for a small percentage of all invasive meningococcal disease (IMD) and between

Whole genome typing of the recently emerged Canadian serogroup W Neisseria meningitidis sequence type 11 clonal complex isolates associated with invasive meningococcal disease

“…From 2000 to 2013, the majority of MenW diseases were caused by strains belonging to the ST-22 CC. Beginning in 2014, a significant shift in the genetic makeup of invasive MenW strains was noted, from ST-22 CC to ST-11 CC (Tsang et al, 2016). Concomitant to this genetic shift in the MenW strain was the increase in the proportion of IMD due to MenW (Tsang et al, 2017).…”

“…MenW ST-11 disease in university students has also been reported from France (Bassi et al, 2017). While no fatal MenW ST-11 cases were identified in one Canadian study (Tsang et al, 2016), both the UK and Australia have reported high case-fatality rates (of 12% and 10.7%, respectively) (Efron et al, 2009;Campbell et al, 2016). Unusual clinical presentations of predominantly gastrointestinal symptoms, but also necrotizing fasciitis, have also been reported from Europe (Campbell et al, 2016;Russcher et al, 2017).…”

“…However, in the mid-1980s, a serogroup C (MenC) strain designated as (which is a genetic variant and member of the ST-11 CC) emerged to cause IMD that eventually spread globally (Jelfs et al, 2000). Sporadic and endemic serogroup W (MenW) IMD has been caused by strains typed as ST-22 CC (Tsang et al, 2016). The first significant outbreak caused by MenW was also due to a ST-11 strain in Saudi Arabia associated with the Hajj pilgrimage in 2000 (Taha et al, 2000).…”

“…A similar increase in MenW disease due to the same strain has been observed in Australia since 2013 and has also led to the introduction of a targeted vaccination program for 0-4 and 15-19-year-olds in a region of western Australia (Martin et al, 2016;Media Statement, 2016). In Canada, the increase in MenW disease due to the ST-11 CC was first noted in 2014, and by 2016, ST-11 MenW was responsible for 19% of all culture-confirmed IMD (Tsang et al, 2016;Tsang et al, 2017).…”

Protecting the most vulnerable age group: a review of MenACWY-TT immunogenicity and safety in infants

“…The South American strain sublineage includes three strains: the South American strain, the original UK strain (a descendent of the South American strain that emerged in 2009 in the United Kingdom), and a further descendent strain, called the UK 2013 strain [17]. These hypervirulent strains belonging to the South American MenWcc11 sublineage are responsible for the rise in MenW incidence observed in Brazil, Argentina, Chile, the United Kingdom, the Netherlands, Spain, and other European countries, Canada, and Australia [17][18][19]. Interestingly, unusual clinical presentations including gastrointestinal symptoms, high morbidity, and increased case fatality rates have been described in several countries associated with IMD because of the South American MenWcc11 sublineage [12,20].…”