[Purulent meningitis: a long-standing problem].

Bacterial meningitis is a problem for Public Health that has to be reviewed periodically. Most of the infections are due to Meningococcus, Haemophilus influenzae or Streptococcus pneumoniae. Seventy per cent of the cases are seen in children less than 5 years old; mortality ranges between 5% to 20% of the patients. Progress has been made with vaccination for Meningococcus types A and C and for H influenzae type B. In Chile, meningococcal meningitis is endemic, with epidemic bouts in the north part of the country. Currently, studies are in progress in Santiago with vaccination against H influenzae type B, in the hope that it can be extended to the rest of the country.