Risk for meningococcal disease associated with the Hajj 2001.

Every year approximately two million pilgrims from more than 140 countries gather in Saudi Arabia for a pilgrimage to the holy places of Islam known as the Hajj. Coinciding with the Hajj pilgrimage during March 2000, Saudi Arabian health officials identified an outbreak of meningococcal disease; a substantial proportion of the isolates were the bacterial strain Neisseria meningitidis serogroup W-135. Four cases of meningococcal disease subsequently were identified among the estimated 15,000 pilgrims returning to the United States, their close contacts, and community. In addition, approximately 400 cases of meningococcal disease caused by N. meningitidis serogroup W-135 wereidentified worldwide during 2000. Whether an outbreak of meningococcal disease will recur in 2001 is unknown.