Descriptive epidemiology of meningococal disease in Chile between the years 1990 and 2019

Abstract

Introduction: Meningococcal disease is an infectious disease caused by the bacterium Neisseria meningitidis (meningococcus). It has gained relevance in Chile over the past ten years due to an increase in lethality. In Chile, there are two meningococcal vaccines in the National Immunization Program: the recombinant vaccine incorporated in 2023 and the conjugate vaccine included in 2014. Objective: To describe the epidemiological situation of Meningococcal disease in Chile between 1990-2019, regarding changes in mortality, lethality, incidence, and predominance of serogroups by year, in order to highlight the relationship of various demographic factors in the disease's epidemiology, and to establish a foundation for future studies on the impact of the recombinant vaccine. Methodology: A descriptive analysis was conducted using data extracted from the Ministry of Health of Chile and the National Institute of Statistics, based on our own calculations. Results: Between 2002-2011, there was a 79% decrease in mortality, followed by a 320% increase in 2012. Incidence and lethality were inversely related from 2000 onwards. The predominance of serogroups varied, with W-135 predominating between 2011-2018, while since 2018, serogroup B has been the most prevalent. Discussion: The conjugate vaccine introduced in 2014 in response to the increased incidence of serogroup W-135 led to a significant decrease in incidence, but not in lethality. Conclusion: It is relevant to consider a future epidemiological study on the effects of the introduction of the recombinant vaccine in the National Immunization Program.