Serogroup W135 meningococcal disease in Hajj pilgrims

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

“…Prior to the spring of 2000, ST-11 MenW has only caused sporadic disease. However, the first large MenW outbreak involving >400 cases from 16 countries due to a ST-11 cc strain was reported among the pilgrims attending the Hajj in Mecca in year 2000 (13,14). Subsequent sporadic cases were thought to be due to pilgrims returning from the Hajj and transmitting the infection to their close contacts, as have been reported in Europe (15).…”

Meningococcal disease in the Middle East and Africa: Findings and updates from the Global Meningococcal Initiative

“…Following the Hajj outbreak in 2000, MenW persisted in Saudi Arabia 44 and a quadrivalent polysaccharide vaccine was introduced and deployed in children <5 years old in the early 2000s (two doses for those <2 years old and one dose for those !2 years old); however, only the older children had a serum bactericidal antibody response. 45 Three quadrivalent ACWY conjugate vaccines are now available.…”

Meningococcal serogroup W and varicella-zoster virus meningitis in an Irish infant

“…This serogroup represented 2.6-4% of all reported N. Meningitidis in the UK, France, and the United States in the 1990s [7][8][9]. Cases of MenW in returning pilgrims and their contacts have been reported in several countries following the Hajj outbreaks of 2000 and 2001 [4,10]. These outbreaks strengthened the reenforced use of MenACWY vaccine, one of the traveler's vaccine.…”

“…Up to the 1980s, N. Meningitidis W135 (NM W135), or MenW was considered a minor serogroup, of little importance [3]. MenW cases became well known during the Hajj-associated outbreaks in 2000 [4]. We describe the case of an 11-month-old girl with meningococcal W135 meningitis on a background of varicella infection.…”