The decline of the incidence of meningococcal disease in Barcelona between 1988 and 2015: the influence of the vaccine against serogroup C

Abstract

Introduction and objective: The purpose of this study was to describe the evolution of meningococcal disease (MD) in the city of Barcelona between 1988 and 2015 and to assess the impact of the vaccine against serogroup C.

Materials and methodology: The evolution of MD and by serogroup was analysed using the information included in the mandatory notification diseases registry. Incidences of all serogroups between the periods of before and after the implementation of the serogroup C vaccine in 2000 were compared. Vaccination coverage among cases, serogroup among vaccinated cases and mortality and case fatality rates were analysed.

Results: MD has evolved from an incidence rate in children aged under 1 of 63.09 cases per 100,000 in 1997-2000 to 15.44 per 100,000 in 2001-2015. All MD serogroups incidences decreased after the implementation of the vaccine, especially for serogroup C among children aged between 1 and 4. Since 2000 vaccine coverage in MD cases by this serogroup was 7.6% while in those affected by serogroup B it was 35.0% (p<.01). Among those vaccinated, 66.4% of cases were serogroup B and 5.2% were C (p<.01). Mortality and case fatality rates were 7.7% and 0.19/100,000 respectively, without significant changes in time regarding case fatality.

Conclusions: Incidence caused by serogroups B and C has decreased after the systematic vaccination against serogroup C. Vaccination against serogroup B could further reduce the impact of this lethal disease which has not decreased during this period.

Keywords: Disease notification; Incidence; Incidencia; Meningitis meningococcal; Meningitis meningocócica; Mortalidad; Mortality; Notificación de enfermedad; Vaccination; Vacunación.