Related Experiment Video

Updated: May 16, 2025

Constructing Mutants in Serotype 1 Streptococcus pneumoniae strain 519/43
06:06

Constructing Mutants in Serotype 1 Streptococcus pneumoniae strain 519/43

Published on: September 11, 2020

1.6K

A global epidemic serotype 14 Streptococcus pneumoniae switching to non-vaccine types

Jinglin Yue1,2, Lei Chen3, Tingzhu Yao1,2

  • 1Biomedical Innovation Center, Beijing Shijitan Hospital, Capital Medical University, Beijing, China.

Microbiology Spectrum
|March 31, 2025
PubMed

Insights

Pneumococcal conjugate vaccines (PCV) reduce vaccine-type bacteria, but non-vaccine types (NVT) increase. A serotype switch from 14 to 15B in a prevalent strain shows adaptive evolution, potentially leading to future pandemics.

Area of Science:

  • Microbiology
  • Genomics
  • Epidemiology

Background:

  • Streptococcus pneumoniae causes pneumonia globally, with vaccine-type strains decreasing post-PCV introduction.
  • Non-vaccine-type (NVT) S. pneumoniae strains have increased, particularly in nasopharyngeal carriage and disease incidence.
  • Serotype switching, involving alterations in the cps gene locus, is a key concern for vaccine effectiveness.

Purpose of the Study:

  • To analyze S. pneumoniae clinical isolates for serotype distribution and evaluate vaccine effectiveness.
  • To identify multidrug-resistant NVT S. pneumoniae, focusing on the CC876 complex and serotype 14 clones.
  • To investigate a potential serotype switch event from serotype 14 to 15B in a prevalent ST4749 strain.

Main Methods:

  • High-throughput sequencing of 166 S. pneumoniae clinical isolates from Xiamen Children's Hospital, China.
  • Serotyping of isolates to assess vaccine type prevalence and identify NVT strains.
  • Genomic analysis to map recombination sites and identify genetic elements involved in serotype switching.

Main Results:

  • A significant increase in NVT S. pneumoniae prevalence was observed, correlating with PCV introduction.
  • Identification of multidrug-resistant NVT S. pneumoniae within the epidemic CC876 complex.
  • Discovery of a serotype 15B/ST4749 strain, likely resulting from a serotype switch from serotype 14/ST4749, involving the cps locus and comC.

Conclusions:

  • The study highlights the adaptive evolution of S. pneumoniae under vaccination pressure, evidenced by serotype switching.
  • The identified novel NVT strain (15B/ST4749) demonstrates potential for future pandemic emergence.
  • Findings offer insights for optimizing S. pneumoniae prevention, control strategies, and vaccine deployment.

Keywords:
Streptococcus pneumoniaeantimicrobial resistancenon-vaccine typeserotype switchvaccine type

More Related Videos

Capsular Serotyping of Streptococcus pneumoniae Using the Quellung Reaction04:25

Capsular Serotyping of Streptococcus pneumoniae Using the Quellung Reaction

Published on: February 24, 2014

45.4K
An Allelotyping PCR for Identifying Salmonella enterica serovars Enteritidis, Hadar, Heidelberg, and Typhimurium12:18

An Allelotyping PCR for Identifying Salmonella enterica serovars Enteritidis, Hadar, Heidelberg, and Typhimurium

Published on: July 22, 2011

21.7K

Related Concept Videos

Viral Mutations00:36

Viral Mutations

A mutation is a change in the sequence of bases of DNA or RNA in a genome. Some mutations occur during replication of the genome due to errors made by the polymerase enzymes that replicate DNA or RNA. Unlike DNA polymerase, RNA polymerase is prone to errors because it is not capable of “proofreading” its work. Viruses with RNA-based genomes, like HIV, therefore accrue mutations faster than viruses with DNA-based genomes. Because mutation and recombination provide the raw material...
32.1K
Lysogenic Cycle of Bacteriophages00:43

Lysogenic Cycle of Bacteriophages

In contrast to the lytic cycle, phages infecting bacteria via the lysogenic cycle do not immediately kill their host cell. Instead, they combine their genome with the host genome, allowing the bacteria to replicate the phage DNA along with the bacterial genome. The incorporated copy of the phage genome is called the prophage. Some prophages can re-activate and enter the lytic cycle. This often occurs in response to a perturbation, such as DNA damage, but can also transpire in the absence of...
61.5K
Viral Recombination00:57

Viral Recombination

Cells are sometimes infected by more than one virus at once. When two viruses disassemble to expose their genomes for replication in the same cell, similar regions of their genomes can pair together and exchange sequences in a process called recombination. Alternatively, viruses with segmented genomes can swap segments in a process called reassortment.
23.1K
Cross-reactivity00:42

Cross-reactivity

Overview
30.9K