"Bacterial Meningitis in children and adolescents: an observational study based on the national surveillance system"

BACKGROUND Bacterial meningitis is a group of life threatening infections that mostly affect children and adolescents, and may be the cause of severe neurological sequelae. Cuba has implemented massive vaccination programmes against both Neisseria meningitidis (serogroup C in 1979 and B in 1987), and Haemophilus influenzae type b (1999), two of the main causal pathogens. We described and discussed some epidemiological aspects of the current status of bacterial meningitis to learn from the Cuban experience. METHODS A nationwide observational study on children and adolescents from 1 to 18 years old was carried out from 1998 to 2003, estimating the incidence and case-fatality rate by age group and causal pathogens, as well as the seasonality and frequency of overcrowded dormitories. The association between disease and attendance to day care centres or boarding schools was estimated by using relative risk (Chi-squared test and Fisher Exact Test). RESULTS The overall number of cases was 1023; the incidence ranged from 3.4 to 8.5 per 100,000 population, with the higher figures in children 1-5 years old (16.8 per 100,000 population). Streptococcus pneumoniae, Haemophilus influenzae type b and Neisseria meningitidis serogroup B were the main identified agents. The average case-fatality rate was 10.5% and the most lethal agents were Streptococcus pneumoniae (27%) and Haemophilus influenzae type b (10.7%). Overall percentage of cases who slept in overcrowded dormitories was 15%, reaching 30.6% in adolescents. Seasonality was only evident among meningococcal meningitis cases between September-October. The attendance to boarding high school showed an association with disease only in 1998 and 1999 (RR = 2.1; p > 0.05). CONCLUSION The highest incidence of bacterial meningitis was observed among children from 1-5 years old. Pneumococcus was both the leading causal and the most lethal agent. Sleeping in overcrowded dormitories was more frequent among adolescents. No strong association was observed between the bacterial meningitis and attendance to day care centres or boarding schools. The incidence of bacterial meningitis in Cuba is declining after massive vaccination programmes against Neisseria meningitidis serogroup B and C and Haemophilus influenzae type b through a national immunisation program.