Pneumococci remain the main cause of complicated pediatric pneumonia in the post-pandemic era despite extensive pneumococcal vaccine use.

Nucleic acid amplification tests (NAATs) greatly enhance the capacity to identify the etiology of pediatric complicated pneumonia. However, the use of pneumococcal conjugate vaccines could reduce the importance of Streptococcus pneumoniae in pediatric complicated pneumonia with the potential emergence of other bacterial agents. Using an expanded NAAT in culture negative pleural fluid or empyema samples collected in 2010-2024 (n = 554) in Portugal, we show that S.

Rebound of pediatric invasive pneumococcal disease in Portugal after the COVID-19 pandemic was not associated with significant serotype changes.

Objectives: The COVID-19 pandemic led to the institution of public health measures in many countries which reduced respiratory infections. We aimed to identify and characterize changes in pediatric (<18 years) invasive pneumococcal disease (pIPD) in Portugal in 2018-2023.

Methods: pIPD cases were identified by culture and molecular methods and stratified by age and serotype.

Sustained increase of paediatric invasive infections dominated by M1 and diverse 12 isolates, Portugal, September 2022 to May 2023.

Since autumn 2022, observed numbers of paediatric invasive group A infections in Portugal (n = 89) were higher than in pre-COVID-19 seasons. Between September 2022 and May 2023, the dominant diagnoses were pneumonia (25/79), mostly with empyema (20/25), and sepsis (22/79). A number of cases required admission to intensive care (27/79) and surgery (35/79), and the case fatality rate was 5.

Annotated Whole-Genome Multilocus Sequence Typing Schema for Scalable High-Resolution Typing of Streptococcus pyogenes.

Streptococcus pyogenes is a major human pathogen with high genetic diversity, largely created by recombination and horizontal gene transfer, making it difficult to use single nucleotide polymorphism (SNP)-based genome-wide analyses for surveillance. Using a gene-by-gene approach on 208 complete genomes of S. pyogenes, a novel whole-genome multilocus sequence typing (wgMLST) schema was developed, comprising 3,044 target loci.