Modelling the evolution of Meningococcal disease in Cuba from 1998-2005

INTRODUCTION: Bacterial meningitis is a life-threatening illness resulting from bacterial infection of the meninges. In Cuba there are about 500 cases of bacterial meningitis every year. Still a little part of these cases is caused by the bacteria N. meningitidis as meningococcal disease (clinical forms: meningitis, septicaemia or both), despite the disease being under vaccination control since 1989. OBJECTIVE: 1. to model how the number of new cases of Meningococcal disease in Cuba changes over time, and 2. to investigate if the models of evolution of meningitis over time can be improved by adding predictors. METHODS: general linear models with Poisson distribution are used. Results: the number of new Meningococcal disease cases is modelled as a quadratic function over time with an elevated number of cases in summer compared to winter. Furthermore, the number of cases is age dependent, and the higher number of cases in the second half of 1999 can be partially explained by the decrease in number of H. influenzae meningitis cases after an immunisation program at that time. CONCLUSIONS: modelling the number of new Meningococcal disease cases indicated it is dependent on season and age. Other possible predictor variables should be explored further, so that the model can be improved for the purpose of prediction.