MENINGITIS CAUSED BY A SEROGROUP W135 CLONE OF THE ET-37 COMPLEX OF NEISSERIA-MENINGITIDIS IN WEST-AFRICA

Meningococci belonging to serogroup W135 caused several cases of menin gococcal meningitis in The Gambia in 1995 and were isolated during a s erogroup A epidemic in Mall in 1994. The eight isolates tested belonge d to the same done of the ET-37 complex and differed in several bands from the pursed-field gel electrophoresis restriction pattern of serog roup C meningococci of the ET-37 complex isolated in Mall. Three of 6 patients infected in The Gambia died, indicating that this W135 clone is virulent. Vaccines that protect only against infections with mening ococci belonging to serogroups A and C are usually used to control out breaks in Africa, although vaccines containing the W135 polysaccharide are available. The findings of this study indicate that outbreaks of meningococcal meningitis in Africa can be associated with serogroup W1 35 infections and that serogrouping is essential before vaccination ca mpaigns are started.