Increased Proportions of Invasive Pneumococcal Disease Cases Among Adults Experiencing Homelessness Sets the Stage For New Serotype 4 Capsular-Switch Recombinants.

Details

• Alternative Title:
  The Journal of Infectious Diseases, 2025, v. 231, no. 4: Increased Proportions of Invasive Pneumococcal Disease Cases Among Adults Experiencing Homelessness Sets the Stage For New Serotype 4 Capsular-Switch Recombinants.
• Journal Article:
  The Journal of Infectious Diseases
• Personal Author:
  Beall, Bernard ; Chochua, Sopio ; Metcalf, Ben ; Lin, Wuling ; Tran, Theresa ; Li, Zhongya ; Li, Yuan ; Bentz, Meghan L. ; Sheth, Mili ; Osis, Gunars ; McGee, Lesley
• Description:
  The Centers for Disease Control and Prevention's Active Bacterial Core surveillance (ABCs) identified increased serotype 4 invasive pneumococcal disease (IPD), particularly among adults experiencing homelessness (AEH).
  
  We quantified increased proportions of IPD cases in AEH during 2016-2022. Employing genomic-based characterization of IPD isolates, we identified serotype-switch variants. Recombinational analyses were used to identify the genetic donor and recipient strain that generated a serotype 4 progeny strain. We performed phylogenetic analyses of the serotype 4 progeny and of the serotype 12F genetic recipient to determine genetic distances.
  
  We identified a cluster of 30 highly related (0-21 nucleotide differences) IPD isolates recovered during 2022-2023, corresponding to a serotype 4 capsular-switch variant. This strain arose through a multifragment recombination event between serotype 4/ST10172 and serotype 12F/ST220 parental strains. Twenty-five of the 30 cases occurred in Oregon. Of 29 cases with known residence status, 16 occurred in AEH. Variant emergence coincided with a 2.6-fold increase (57 to 148) of cases caused by the serotype 4/ST10172 donor lineage in 2022 compared to 2019 and its first appearance in Oregon. Most serotypes showed sequential increases of AEH IPD/all IPD ratios during 2016-2022 (eg, for all serotypes combined, 247/2198, 11.2% during 2022 compared to 405/5317, 7.6% for 2018-2019, P < .001). Serotypes 4 and 12F each caused more IPD than any other serotype in AEH during 2020-2022 (207 combined case isolates accounting for 38% of all IPD in AEH).
  
  Expansion and increased transmission of serotypes 4 and 12F among adults potentially led to recent genesis of an impactful hybrid serotype-switch variant.
• Content Notes:
  Author manuscript
• Subjects:
  • Humans
  • Streptococcus pneumoniae
  • Pneumococcal Infections
  • Serogroup
  • Ill-Housed Persons
  • Adult
  • Phylogeny
  • Recombination, Genetic
  • Female
  • Male
  More +
• Keywords:
  • invasive pneumococcal disease
  • adults experiencing homelessness
  • serotype switch variant
  • multifragment recombination
  • western Active Bacterial Core Surveillance sites
• Source:
  The Journal of Infectious Diseases, 2025, v. 231, no. 4
• DOI:
  https://doi.org/10.1093/infdis/jiae453
• ISSN:
  0022-1899 ; 1537-6613
• Pubmed ID:
  39259351
• Pubmed Central ID:
  PMC11893508
• Document Type:
  Text
• Funding:
  CC999999/ImCDC/Intramural CDC HHSUnited States/ ; CC/CDC HHSUnited States/
• Genre:
  Journal Article
• Place as Subject:
  Oregon
• Pages in Document:
  871-882 (21 pdf pages)
• Volume:
  231
• Issue:
  4
• Download URL:
  https://stacks.cdc.gov/view/cdc/262025/cdc_262025_DS1.pdf
• File Type:
  [PDF - 1.48 MB]
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha-512:a3ba867f40f9589d88c44b1b04f5c77c0ca7defd8faba36ea2b83a0d5432b931c085d1342e20df87fe15002f61a2ad49be139c8a39522696d5c935b91e9f4bc6