1. Changing patterns of case ascertainment and trends in meningococcal disease in England and Wales;Ramsay;CDR Review,1997
2. Surveillance of bacterial meningitis in Europe;Noah,1995
3. Epidemiology and prevention of meningococcal disease;Riedo;Pediatr Inf Dis J,1995
4. The epidemiology of acute bacterial meningitis in tropical Africa;Greenwood,1987
5. Group A meningococcal carriage in travellers returning from Saudi Arabia;Moore;JAMA,1988