In a major break through, a vaccine for meningitis B, caused by bacterial infection, has performed well in a preliminary trial in Britain. Meningitis is inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. Vaccines are available against meningitis A and C, but none yet exists for meningitis B, the leading cause of bacterial meningitis throughout the world. Annually there are between 20,000-80,000 cases of meningitis B all over the world and of these 10 per cent result in death.