Antimicrobial susceptibility and serotype replacement of Streptococcus pneumoniae in children before and after PCV13 introduction in Taiwan
Related Experiment Video
Updated: Aug 28, 2025
Constructing Mutants in Serotype 1 Streptococcus pneumoniae strain 519/43
Published on: September 11, 2020
Hsiang Huang1, Chien-Yu Lin2, Nan-Chang Chiu3
1Department of Pediatrics, MacKay Children's Hospital, MacKay Memorial Hospital, Taipei, Taiwan.
Insights
The 13-valent pneumococcal conjugate vaccine (PCV13) effectively reduced invasive pneumococcal disease (IPD) in children. However, non-vaccine serotypes 15A and 23A increased, requiring ongoing monitoring of antimicrobial resistance in Streptococcus pneumoniae.
Area of Science:
- Pediatric Infectious Diseases
- Vaccinology
- Microbiology
Background:
- The 13-valent pneumococcal conjugate vaccine (PCV13) was integrated into Taiwan's national immunization program in 2015.
- PCV13 introduction has influenced the epidemiology and antimicrobial susceptibility patterns of circulating Streptococcus pneumoniae strains.
- Understanding these shifts is crucial for public health strategies targeting pediatric pneumococcal infections.
Purpose of the Study:
- To analyze the serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae isolates from pediatric infections before and after PCV13 introduction.
- To evaluate the impact of PCV13 on the incidence of invasive pneumococcal disease (IPD) and non-IPD in children.
Main Methods:
- Retrospective analysis of 322 Streptococcus pneumoniae isolates from pediatric patients between January 2010 and December 2020.
- Samples were collected from three hospitals in Taiwan.
- Epidemiological data, serotyping, and antimicrobial susceptibility testing were performed, comparing periods before and after PCV13 administration.
Main Results:
- The incidence of invasive pneumococcal disease (IPD) significantly decreased post-PCV13 introduction (29.7% to 7.3%).
- Serotype 19A prevalence initially rose then declined, while serotypes 15A and 23A became dominant after 2015.
- Antimicrobial non-susceptibility to penicillin, cefotaxime, and ceftriaxone generally decreased, though resistance to cefotaxime and ceftriaxone showed an upward trend in 2020.
Conclusions:
- PCV13 demonstrates significant effectiveness in reducing pediatric IPD incidence.
- Emergence of non-vaccine serotypes (15A, 23A) necessitates continued surveillance.
- Monitoring antimicrobial non-susceptibility trends in Streptococcus pneumoniae is essential for guiding treatment and prevention strategies.
Background:
Since 2015, 13-valent pneumococcal conjugate vaccine (PCV13) was included in the national immunization program in Taiwan. Subsequently, the serotypes of the main circulating Streptococcus pneumoniae strains have changed. PCV administration is also associated with changes in the antimicrobial susceptibility of S. pneumoniae strains. Therefore, in this study, we analyzed the serotype distribution and antimicrobial susceptibility of S. pneumoniae in pediatric infections.
Methods:
Children with S. pneumoniae infections, including invasive pneumococcal disease (IPD) and non-IPD, were enrolled from January 2010 to December 2020. The samples were collected from Mackay Memorial Hospital, MacKay Children's Hospital, and Hsinchu Mackay Hospital in Taiwan. We analyzed the epidemiology of sample collection site, infection diagnosis, and the serotype and antimicrobial susceptibility of S. pneumoniae strains. The study period was divided into time points before and after PCV13 administration.
Results:
In total, 322 isolates were collected during the study period. The incidence of IPD declined annually, from 29.7% before 2015 to 7.3% after 2015 (p < 0.001). The prevalence of serotype 19 A had increased gradually since 2010 but declined rapidly after 2013. Serotypes 15 A and 23 A were the most common serotypes after 2015. The non-susceptibility of the S. pneumoniae isolates to penicillin, cefotaxime, and ceftriaxone decreased. Based on meningitis breakpoints, the non-susceptibility to cefotaxime and ceftriaxone gradually decreased, but increased in 2020.
Conclusion:
PCV13 was considerably effective in reducing the incidence of IPD in children; however, the prevalence of serotypes 15 A and 23 A increased. The increase in antimicrobial non-susceptibility caused by non-vaccine serotypes must be continuously monitored.
