Invasive Pneumococcal Strain Distributions and Isolate Clusters Associated With Persons Experiencing Homelessness During 2018

Abstract

Background We aimed to characterize invasive pneumococcal disease (IPD) isolates collected from multistate surveillance in the United States during 2018 and examine within-serotype propensities of isolates to form related clusters. Methods We predicted strain features using whole genome sequencing obtained from 2885 IPD isolates obtained through the Center for Disease Control and Prevention’s Active Bacterial Core surveillance (ABCs), which has a surveillance population of approximately 34.5 million individuals distributed among 10 states. Phylogenetic analysis was provided for serotypes accounting for ≥27 isolates. Results Thirteen-valent pneumococcal conjugate vaccine (PCV13) serotypes together with 6C accounted for 23 of 105 (21.9%) of isolates from children aged 70% of IPD in ABCs; however, PCV13 serotype 3 is the most common IPD serotype overall. Serotypes most common among PEH were more often associated with temporally related clusters identified both among PEH and among persons not reportedly experiencing homelessness.