Invasive meningococcal disease in older adults in North America and Europe: is this the time for action? A review of the literature

Abstract

Background Neisseria meningitidis is an encapsulated Gram-negative diplococcus that asymptomatically colonises the upper respiratory tract in up to 25% of the population (mainly adolescents and young adults). Invasive meningococcal disease (IMD) caused by Neisseria meningitidis imposes a substantial public health burden,. The case fatality rate (CFR) of IMD remains high. IMD epidemiology varies markedly by region and over time, and there appears to be a shift in the epidemiology towards older adults. The objective of our review was to assess the published data on the epidemiology of IMD in older adults (those aged ≥ 55 years)in North America and Europe. Such information would assist decision-makers at national and international levels in developing future public health programmes for managing IMD. Methods A comprehensive literature review was undertaken on 11 August 2020 across three databases: EMBASE, Medline and BIOSIS. Papers were included if they met the following criteria: full paper written in the English language; included patients aged ≥ 56 years; were published between 1/1/2009 11/9/2020 and included patients with either suspected or confirmed IMD or infection with N. meningitidis in North America or Europe. Case studies/reports/series were eligible for inclusion if they included persons in the age range of interest. Animal studies and letters to editors were excluded. In addition, the websites of international and national organisations and societies were also checked for relevant information. Results There were 5,364 citations identified in total, of which 76 publications were included in this review. We identified that older adults with IMD were mainly affected by serogroups W and Y, which are generally not the predominant strains in circulation in most countries. Older adults had the highest CFRs, probably linked to underlying comorbidities and more atypical presentations hindering appropriate timely management. In addition, there was some evidence of a shift in the incidence of IMD from younger to older adults. Conclusions The use of meningococcal vaccines that include coverage against serogroups W and Y in immunization programs for older adults needs to be evaluated to inform health authorities’ decisions of the relative benefits of vaccination and the utility of expanding national immunization programmes to this age group.

Changing patterns of invasive meningococcal disease and future immunization strategies

“… 74 , 75 Atypical symptoms of IMD have been reported in older adults, which makes diagnoses difficult, allowing the disease to progress without treatment. 76 The financial burden of hospitalization and treatment of IMD-related sequelae on the individual and society is substantial. 71 , 74 Vaccinating older adults ≥50 years of age irrespective of the risk factors can reduce the healthcare burden and mortality in this age group.…”

Meningococcal disease within the Gulf Cooperation Council Countries

“…Similar patterns have been observed in other settings with established infant or adolescent meningococcal immunization programs, where declines in vaccine eligible age-groups have led to a greater relative burden in adults. 7 , 13 , 14 Compulsory Hajj/Umrah pilgrim MenACWY immunization in individuals within these GCC Countries could also have had some impact.…”

“…Globally, the greatest burden and highest incidence of IMD is in infants and young children, with a second peak in adolescents, 1 , 4 , 5 while more recent epidemiological trends indicate an increased burden in adults and the elderly, where case fatality rates (CFRs) are also higher. 1 , 7 , 13 , 14 Global epidemiology shows substantial geographical variation, both in terms of disease burden and in the relative importance of specific serogroups in local or regional IMD epidemiology, 1 , 4 , 5 with temporal shifts driven by both cyclic epidemiologic patterns, disease outbreaks, 15 and the introduction of effective vaccines against major pathogenic serogroups. Use of conjugated monovalent MenC vaccines, quadrivalent MenACWY vaccines and protein-based vaccines against MenB in national immunization programs (NIPs), mostly targeting infants and adolescents, has led to substantial declines in the IMD burden in these at-risk populations, 1 , 5 , 16 , 17 …”

Demographic Features of Invasive Meningococcal Disease in Taiwan, 1993 to 2020, and Genetic Characteristics of Neisseria meningitidis Isolates, 2003 to 2020

“…A meta-analysis study indicated that, for laboratory-confirmed IMD cases reported between January 2000 and May 2008, the predicted CFR was high in infants (9.0%), gradually decreased to 7.0% in 7 year olds, subsequently increased to reach a peak of 15.0% in young adults, remained steady in adults aged between 28 and 45 years, and then rose rapidly in older adults ( 1 ). Older adults usually have the highest mortality rate of IMD, which could be linked to underlying comorbidities and more atypical presentations hindering appropriate timely diagnosis and management and the dysfunction of the immune response ( 14 , 40 ). However, little has been discussed on the elevated CFRs in the young adult group.…”