Impact of the 13-valent conjugate pneumococcal vaccine on the incidence of invasive pneumococcal disease in Catalonia: Retrospective study, 2014–2015 vs. 2017–2018

Abstract

IntroductionInvasive pneumococcal disease (IPD) is a major public health problem worldwide with high morbidity and mortality that causes a wide spectrum of diseases, from otitis media to sepsis and meningitis. In Catalonia, the universal immunization program with the 13-valent conjugated pneumococcal vaccine (Pn13 vaccine) began in 2016. The objective of this study was to analyse the impact of the 13-valent pneumococcal conjugate vaccine (PCV13 vaccine) on the incidence of IPD during the years 2017−2018 compared to the years 2014−2015. MethodRetrospective study of IPD cases notified by reporting laboratories to the Microbiological Reporting System of Catalonia (MRSC) from 2014 to 2018. Incidence rates (IR) and relative risk (RR) were calculated. ResultsThe global incidence of IPD (2014–2018) was 12,6 cases per 100,000 persons/year. Comparing 2017−2018 vs 2014−2015, the incidence of IPD caused by the serotypes included in the PCV13 vaccine has decreased in children <5 years by 46% while it has remained stable in the rest of the groups. Serotype 3, despite being included in the PCV13 vaccine, remained a high incidence. In contrast, the incidence of IPD caused by non PCV13 serotypes increased in adults aged 20−64 years (35%) and ≥65 years (27%), mainly due to the increase of serotype 8. ConclusionsPCV13 introduction is beneficial for both, vaccinated and non-vaccinated people (due to herd immunity). However, a precise and continuous epidemiological surveillance of IPD must be carried out to detect changes in the incidence of the disease and circulating serotypes.