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Neisseria meningitidis serogroup W135 in Portugal: presence of the ST-11/ET-37 clonal complex
E Ferreira1, R Dias, D Giorgini
1Antibiotic Resistance Unit, Centre of Bacteriology, National Institute of Health Dr. Ricardo Jorge, Avenida Padre Cruz, 1649-016, Lisbon, Portugal.
Pathologie-Biologie
|January 9, 2008
Abstract:
Invasive serogroup W135 Neisseria meningitidis strains were isolated in Portugal between 1995 and 2002. Nine of 12 isolates showed "Hajj-2000"-associated phenotypes and belonged to the ST-11/ET-37 clonal complex. Pulsed-field gel electrophoresis clustered the ST-11/ET-37 isolates together with the "Hajj-2000" strain although the profiles were distinguishable.
Insights
Invasive Neisseria meningitidis serogroup W135 strains in Portugal showed "Hajj-2000" phenotypes and belonged to the ST-11/ET-37 clonal complex. Pulsed-field gel electrophoresis confirmed links to the "Hajj-2000" strain.
Area of Science:
- Microbiology
- Epidemiology
- Infectious Diseases
Background:
- Invasive meningococcal disease (IMD) is a significant public health concern.
- Serogroup W135 Neisseria meningitidis has emerged as a cause of IMD outbreaks globally.
- Understanding the genetic characteristics of circulating strains is crucial for disease control.
Purpose of the Study:
- To characterize Neisseria meningitidis serogroup W135 isolates from Portugal between 1995 and 2002.
- To investigate the clonal origins and potential epidemiological links of these invasive strains.
Main Methods:
- Isolation and serogrouping of Neisseria meningitidis strains.
- Phenotypic characterization, including "Hajj-2000"-associated markers.
- Molecular typing using pulsed-field gel electrophoresis (PFGE).
- MLST (Multilocus Sequence Typing) to determine sequence types (STs) and clonal complexes.
Main Results:
- Twelve invasive serogroup W135 Neisseria meningitidis isolates were identified.
- Nine of these isolates exhibited "Hajj-2000"-associated phenotypes.
- All nine isolates belonged to the ST-11/ET-37 clonal complex.
- PFGE analysis showed clustering of ST-11/ET-37 isolates with the "Hajj-2000" strain, though distinct profiles were observed.
Conclusions:
- The ST-11/ET-37 clonal complex, associated with the "Hajj-2000" strain, was prevalent among invasive serogroup W135 Neisseria meningitidis isolates in Portugal during the study period.
- These findings suggest the potential for international spread and local establishment of specific meningococcal clones.
- Continued surveillance and molecular characterization are essential for tracking invasive meningococcal disease epidemiology.
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