title: The rise and fall of epidemic Neisseria meningitidis serogroup W135 meningitis in Burkina Faso, 2002-2005.
abstract: BACKGROUND
  During the period 2001-2002, Burkina Faso reported its first meningitis epidemic due to Neisseria meningitidis (Nm) serogroup W135, prompting concerns that this serogroup would persist as a cause of epidemic disease.
  
  
  METHODS
  During the period 2002-2005, hospital- and population-based surveillances were conducted in 3 districts in Burkina Faso. Etiology was determined by culture, polymerase chain reaction (PCR), and latex agglutination. Reference laboratories determined phenotype and genotype.
  
  
  RESULTS
  Of 2004 subjects who received a lumbar puncture, 265 were identified as having Nm, including 93 who had Nm serogroup A (NmA) and 146 who had Nm serogroup W135 (NmW135). Over the study period, the proportion of cases due to NmW135 decreased by >75%, primarily because of decreased occurrence among young children and in a single district. During peak epidemic months, the annualized incidence of NmW135 decreased from 146 cases to <1 case per 100,000 population. All but 2 NmW135 isolates were phenotype W135:2a:P1.5,2 (sequence type [ST]-11 clonal complex). All NmA isolates were phenotype A:4:P1-9 (ST-2859 of the ST-5 clonal complex). We identified 1 isolate from serogroup Y (ST-11 clonal complex), 1 isolate from serogroup X that was similar to strains previously associated with epidemic disease, and 1 isolate from serogroup W135 of the newly described ST-4375 complex.
  
  
  CONCLUSIONS
  For unknown reasons, serogroup W135 achieved epidemic status, primarily among young children, and then largely disappeared over a short time period. The continued circulation of multiple strains with epidemic potential emphasizes the need for ongoing surveillance and the potential benefit of vaccines that are protective across serogroups.
authors.affiliation: Université de Ouagadougou.
authors.forename: Yves
authors.initials: Y
authors.lastname: Traoré
authors.forename: Berthe-Marie
authors.initials: BM
authors.lastname: Njanpop-Lafourcade
authors.forename: Kokou-Louis-Sewonou
authors.initials: KL
authors.lastname: Adjogble
authors.forename: Mathilde
authors.initials: M
authors.lastname: Lourd
authors.forename: Seydou
authors.initials: S
authors.lastname: Yaro
authors.forename: Boubacar
authors.initials: B
authors.lastname: Nacro
authors.forename: Aly
authors.initials: A
authors.lastname: Drabo
authors.forename: Isabelle
authors.initials: I
authors.lastname: Parent du Châtelet
authors.forename: Judith E
authors.initials: JE
authors.lastname: Mueller
authors.forename: Muhamed-Kheir
authors.initials: MK
authors.lastname: Taha
authors.forename: Ray
authors.initials: R
authors.lastname: Borrow
authors.forename: Pierre
authors.initials: P
authors.lastname: Nicolas
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Alonso
authors.forename: Bradford D
authors.initials: BD
authors.lastname: Gessner
mesh_terms: D000293:Adolescent; D000328:Adult; D002050:Burkina Faso / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D006801:Humans; D007223:Infant; D008585:Meningitis, Meningococcal / Q000453:epidemiology* / Q000517:prevention & control; D022401:Meningococcal Vaccines / Q000008:administration & dosage; D038582:Neisseria meningitidis, Serogroup W-135 / Q000145:classification / Q000302:isolation & purification*; D012703:Serotyping
chemical_list: D022401:Meningococcal Vaccines