ABSTRACT
Invasive meningococcal disease (IMD) is a disease caused by Neisseria meningitidis. IMD has been notifiable since 1901 and must be reported to the National Epidemiological Surveillance Network (RENAVE). This study shows the results obtained during the 2018-2019 and 2019-2020 seasons. During the 2018-2019 season, the incidence of invasive meningococcal disease continued the increasing trend observed during the previous five seasons. Mainly due to the increase of cases of serogroup W and Y. The incidence of cases reported during the 2019/2020 season decreased by 31,3% compared to the previous 2018/2019 season. Incidence decreased in all serogroups and in all age groups. This decrease could be due to the addition of several factors. First, this season coincided, in part, with the onset of the COVID pandemic, and measures to contain the spread of SARS-CoV-2 affected its transmission. Second, the tetravalent conjugate vaccine (Men ACWY) was introduced into the vaccination schedule in adolescents (12 years old) and finally, other limitations of surveillance during this year could affect the decrease.