Molecular Characterization of Invasive Isolates of Neisseria meningitidis in Casablanca, Morocco

Abstract

Meningococcal epidemiology may change unpredictably, and typing of isolates is crucial for the surveillance of invasive meningococcal disease (IMD). Few data are available regarding the meningococcal epidemiology in countries of North Africa. We aimed to explore invasive meningococcal isolates from the Casablanca region in Morocco. We used whole-genome sequencing (WGS) to characterize 105 isolates from this region during the period of 2011 to 2016. Our data showed that the majority ( = 100) of the isolates belonged to serogroup B. Genotyping indicated that most of the isolates ( = 62) belonged to sequence type 33 of clonal complex 32. The isolates also showed the same PorA and FetA markers and clustered together on the basis of WGS phylogenetic analysis; they seemed to correspond to an expansion of local isolates in the Casablanca region, as reported for similar isolates in several other countries. These data suggest that serogroup B isolates may predominate in Morocco, which may have an important impact in the design of vaccination strategies.

The Global Meningococcal Initiative meeting on prevention of meningococcal disease worldwide: Epidemiology, surveillance, hypervirulent strains, antibiotic resistance and high-risk populations

“…Surveillance data indicated that the incidence and prevalence of Nm serogroups continually varies both geographically and temporally [23,24]. Currently, meningococcal serogroup B (MenB) is a major cause of IMD in North America, South America, Australia, North Africa, and Europe, although a decreasing incidence trend is being observed [25], which was supported by the data presented from other countries at the 2018 GMI meeting [10,11,[26][27][28][29][30]. The incidence and prevalence of MenB naturally fluctuates over time and is currently at an all-time low; the reasons for this were unknown, but it was hypothesized that the introduction of a smoking ban in public places in some countries may have played a role.…”

“…Due to the diverse standards of IMD surveillance systems globally and country/regional differences in IMD epidemiology, incidence estimates for countries represented at the meeting varied drastically, particularly in terms of the time period(s) cited. Overall, current country-specific incidence levels of IMD reported during the meeting ranged from 0.01 to 0.02 cases per 100,000 persons per year in Mexico (2014-2017) [9] to 2─3.6 cases per 100,000 persons per year in Morocco (2012-2016) [7,10]. The incidence of IMD cases per 100,000 population was 0.70, 0.12, and 0.30 in Europe [11], U.S.A. [12] and Canada in 2015 [13], respectively.…”

Epidemiological profile of Neisseria meningitidis in Casablanca, Morocco: 2010–2019

“…Surveillance of confirmed IMD cases in Casablanca (Morocco) highlighted three important changes: an increase of invasive infection cases due to serogroup B strains with a prevalence ranging from 75.5 % [ 16 ] to 93.06 % cases; an increase in serogroup W, nine cases in our study which have been confirmed since 2010. Finally, we note the presence of three cases of serogroup Y with a first appearance in 2013 in the Casablanca region [ 17 ]. In the Maghreb region, Meningococcal serogroup B represents 80.4 % of cases in Tunisia [ 18 ], moreover, in Algeria it represents 46.7 % of cases between 2003 and 2013 [ 19 ].…”

“…This situation was similar to that of the meningitis belt during this period. Since that date, we have witnessed a progressive decrease in the prevalence of serogroup A [ 16 ], and an increase in serogroup B [ 17 ]. This epidemiological variation could be related to the proximity and trade with Europe and partly due to the vaccination of pilgrims (polysaccharide vaccine and ACXY conjugate vaccine).…”

A Review of the Epidemiology of Invasive Meningococcal Disease and Vaccination Strategies in North Africa

“…Six articles were identified, including characterization studies of N. meningitidis isolates through whole genome sequencing, 12 and serotyping and subtyping analyses. 13,14 Retrospective and prospective studies on hospitalized children 15,16 and a review of GMI roundtable discussions of meningococcal surveillance and preventative programs were also included.…”