Active metropolitan area surveillance for hospital admissions related to invasive infection with Neisseria meningitidis will be conducted at the 12 centers in the IMPACT network in collaboration with Public Health officials, local infection specialists and infection control practitioners during the interval from January 1, 2016 to December 31, 2022.

The objectives are 3-fold, including:

1. description of affected children and adults and the nature and outcome of the infection episodes
2. incidence rate determination in defined populations, by age, serogroup and study year
3. detailed study of the organisms recovered from cases

Inclusion Criteria:Neisseria meningitidis isolated or detected by PCR from a normally sterile body site or fluid, such as blood, CSF, joint fluid, pleural, peritoneal, pericardial fluid or tissue biopsy -

Exclusion Criteria:patients diagnosed based only on

1. clinical signs, gram stain, or antigen test
2. meningococci isolated only from respiratory tract, including conjunctiva, sinuses, middle ear/mastoid, throat, peritonsillar abscess, cervical lymph node, tracheal aspirate, bronchial lavage etc -

Any person admitted with confirmation of an invasive meningococcal infection at all participating Centers across Canada