Headlines - Invasive meningococcal disease (IMD) caused by W135

A recent spike in cases of W135 meningitis has prompted the InVS and the National Reference Center for Meningococcal Diseases to take action (11 cases reported between January 1 and March 3, 2012, compared to 11 for the entire year of 2010 and 14 in 2011). Among the 11 cases in 2012, the CNR confirmed 5 cases of W135 IIM in individuals returning from sub-Saharan Africa (1 child from Benin, 2 adults from Senegal, and 1 child from Mali) or who had been in contact with a person returning from sub-Saharan Africa (1 child). These 5 cases also presented with extrameningeal complications (arthritis, pulmonary complications, etc.).No epidemiological link was found between these 5 cases, in which the CNR identified an identical clone of the W135:2a:P1.5,2 phenotype belonging to the ST-11 epidemic clonal complex, which is not usually found at this frequency in France (0 in 2010, 2 in 2011, and 5 since early 2012). The W135 serogroup has been present for many years in all countries of the Sahel region (from Senegal in the west to Ethiopia in the east), where seasonal epidemics occur annually during the dry season from January to May. Its circulation has intensified since 2001, following the epidemic linked to the pilgrimage to Mecca in 2000, and it has since been implicated in epidemics in sub-Saharan Africa.

These factors suggest that, for identified cases belonging to serogroup W135, healthcare providers should inquire about a recent return from travel to the African continent (within 10 days prior to hospitalization) or a recent return from travel by a close contact (within 3 weeks prior to the case’s hospitalization).From a public health perspective, it is important to reiterate the recommendations of the DGS circular and the vaccination schedule for the prevention of serogroup meningococcal meningitis (MM), particularly serogroups Y and W135:

• Individuals identified as close contacts of a case of Y/W135 meningococcal meningitis should receive, in addition to chemoprophylaxis, vaccination with a non-conjugated tetravalent vaccine from ages 2 to 10 (Mencevax®) and a conjugated tetravalent ACYW135 vaccine starting at age 11 (Menveo®).

• Vaccination with the ACW135Y conjugated meningococcal vaccine (Menveo®) is recommended in the vaccination schedule starting at age 2 in cases of properdin deficiency, terminal complement component deficiency, anti-C5A therapy, or functional or anatomical asplenia.