Meningococcal disease and influenza-like syndrome: a new approach to an old question.

The temporal and spatial association of meningococcal disease and influenza-like syndrome (ILS) was assessed from surveillance data on these diseases in France for a 6-year period (1985-1990). Using time series methods to account for the usual seasonal pattern meningococcal disease, the incidence of meningococcal disease in a given week was found to be linked to incidence of ILS in the 5 previous weeks but not to that in subsequent weeks. Geographic spread of meningococcal disease correlated with spread of ILS. This study also suggests that meningococcal disease is more severe for a 2-month period during and after an ILS epidemic: The proportion of cases with purpura fulminans increased by 24% and those resulting in death by 26% during this period. No shift in the age distribution was observed. When an ILS epidemic is identified, medical practitioners should be informed of the likelihood of an increased incidence and severity of meningococcal disease.