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Isolation of Brain-infiltrating Leukocytes
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Published on: June 13, 2011

Serogroup W135 meningococcal disease in Hajj pilgrims

M K Taha, M Achtman, J M Alonso

    Lancet (London, England)
    |February 24, 2001
    PubMed

    Insights

    An outbreak of W135 meningococcal disease was linked to pilgrims returning from Saudi Arabia. This clonal strain (ET-37) highlights the need to reassess traveler vaccination strategies against meningococcal disease.

    Area of Science:

    • Microbiology
    • Epidemiology
    • Immunology

    Background:

    • An outbreak of W135 meningococcal disease occurred in 2000 among pilgrims returning from Saudi Arabia and their contacts.
    • Clinical isolates from England and France were analyzed and compared with international reference strains.

    Discussion:

    • Typing methods revealed the W135 isolates were of clonal origin (ET-37).
    • These isolates were closely related to other meningococci known for causing disease clusters.

    Key Insights:

    • The W135 meningococcal disease outbreak demonstrated a clonal spread.
    • Genetic relatedness was observed between the outbreak strains and previously identified cluster-causing meningococci.

    Outlook:

    • The findings necessitate a review of current vaccination strategies for international travelers.
    • Enhanced surveillance and targeted vaccination may be required to prevent future outbreaks.

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