Invasive Bacterial Infections in Subjects with Genetic and Acquired Susceptibility and Impacts on Recommendations for Vaccination: A Narrative Review

Abstract

The WHO recently endorsed an ambitious plan, “Defeating Meningitis by 2030”, that aims to control/eradicate invasive bacterial infection epidemics by 2030. Vaccination is one of the pillars of this road map, with the goal to reduce the number of cases and deaths due to Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae and Streptococcus agalactiae. The risk of developing invasive bacterial infections (IBI) due to these bacterial species includes genetic and acquired factors that favor repeated and/or severe invasive infections. We searched the PubMed database to identify host risk factors that increase the susceptibility to these bacterial species. Here, we describe a number of inherited and acquired risk factors associated with increased susceptibility to invasive bacterial infections. The burden of these factors is expected to increase due to the anticipated decrease in cases in the general population upon the implementation of vaccination strategies. Therefore, detection and exploration of these patients are important as vaccination may differ among subjects with these risk factors and specific strategies for vaccination are required. The aim of this narrative review is to provide information about these factors as well as their impact on vaccination against the four bacterial species. Awareness of risk factors for IBI may facilitate early recognition and treatment of the disease. Preventive measures including vaccination, when available, in individuals with increased risk for IBI may prevent and reduce the number of cases.

Screening for Immunodeficiencies in Children With Invasive Pneumococcal Disease: Six-year Experience From a UK Children’s Hospital

“…Moreover, population vaccination coverage and local epidemiology will influence the proportion of patients with underlying comorbidities and thereby alter the number needed to test. 19 Vaccination with PCV7 was introduced in the United Kingdom in 2006 and replaced by PCV13 in April 2010. Incidence of IPD has subsequently reduced dramatically, with an incidence of IPD in infants of 19/100.000 in the period 2013 to 2016.…”

Product review on the IMD serogroup B vaccine Bexsero®

“…The capsule is a major meningococcal virulence determinant, and non-capsulated meningococcus do not generally cause invasive disease but may be detected in immune-deficient subjects. 12 N. meningitidis is assigned to one of 12 established serogroups based on the immunochemical specificity of the capsular polysaccharides; that reflect genetic differences in their capsule loci. Only six of these serogroups (A, B, C, W, X, and Y) cause nearly all IMD worldwide.…”

Editorial for the Special Issue: Bacterial Meningitis—Epidemiology and Vaccination

“…They drew attention to the importance of low-cost vaccines for global introduction, the expanding range of conjugate vaccines and the more recently developed meningococcal protein vaccines, and the challenges in reaching prevention goals. As vaccines are developed and vaccination programmes expanded, Deghmane and Taha [ 7 ] made the case that preventing disease among those at higher risk will become increasingly important.…”