Serotype epidemiology and antibiotic resistance of pneumococcal isolates colonizing infants in Botswana (2016-2019)

Pediatric Pleural Effusion and Pneumococcal Vaccination Trends in the Pre- and Post-COVID Era: A Single-Centre Retrospective Study

Background/Objectives: Pleural effusion represents an accumulation of fluid in the pleural cavity, frequently associated with pneumonia. There has been a gradual increase in cases among children in recent years, with a notable rise during the post-pandemic period, potentially due to immune debt, decreased vaccination coverage, and changes in pathogen dynamics. Methods: We enrolled 66 children with pleural effusion treated at the Children's Emergency Clinical Hospital, Brasov, between January 2019 and September 2024. We analyzed the data on demographics, symptoms, vaccination status, hospitalization, and treatments to assess the trends in the incidence and clinical features. Results: The median age was 5 years (ranging from 3 months to 17 years). Most patients were male (57.5%) from rural areas (34.8%). Only 40.9% fulfilled the vaccination schedule of Romania. We observed a rise in hospitalizations in the last two years, with 16 cases in 2023 and 15 in 2024, and most were being admitted in April (15.5%). Patients mainly had severe (36%) and medium (26%) acute respiratory failure. S. pneumoniae was the most common isolate with two cases each of serotype 1, 14, and 23A, and one case each of serotype 3, 31, and 34, followed by H. influenzae and P. aeruginosa. Treatment was mostly with ceftriaxone (69.6%), Vancomycin (63.6%), Meropenem (53.0%), and Teicoplanin (25.7%). Some children required thoracic drainage (34.8%). Complications like pneumothorax (16.6%), polyserositis (4.5%), and pneumomediastinum (3.0%) were found. Conclusions: The rise in pleural effusion cases may be influenced by various factors, such as changes in pathogen behavior or host immune responses following the pandemic. Further research is needed to understand these potential mechanisms. The emergence of non-PCV20 strains and the common occurrence of serotype 3 infections point out the need to study serotype trends and evaluate whether expanding vaccine programs could be beneficial.

Nasopharyngeal Carriage, Antimicrobial Resistance, and Serotype Distribution of Streptococcus pneumoniae in Children Under Five in Lebanon: Baseline Data Prior to PCV13 Introduction

BACKGROUND

The nasopharyngeal carriage of Streptococcus pneumoniae can be the source of transmission between humans and the starting step towards invasive pneumococcal diseases. Data on the carriage of pneumococci in children before and after the pneumococcal conjugate vaccines (PCV) integration in a country are essential for monitoring any change in pneumococcal carriage serotypes and their antimicrobial-resistance profiles.

METHODS

We investigated the epidemiology of S. pneumoniae carriage among children younger than five years old in Tripoli, Lebanon, in 2016, the same year of integration of PCV13 in the country's Expanded Program on Immunization.

RESULTS

Of 104 participating children, 57 (54.8%) gave a positive culture for S. pneumoniae. Antimicrobial susceptibility testing revealed that 26.3% of isolates were multidrug-resistant. Resistance was detected mainly against oxacillin (77.2%), tetracycline (29.8%), erythromycin (22.8%), trimethoprim-sulfamethoxazole (22.8%), clindamycin (19.3%), minocycline (19.3%), and teicoplanin (1.8%). Serotyping analysis identified 14 distinct serotypes, with only 31.3% and 50% of isolates corresponding to vaccine serotypes covered by PCV13 and PCV20, respectively. The most common serotypes were 11A, 19F, 23A, and those of serogroup 24 (Sg24) accounted for 37.5% of the serotyped isolates.

CONCLUSIONS

Our findings have revealed the circulation of a pool of pneumococci isolates with high levels of antibiotic resistance and different degrees of likelihood of causing invasive diseases in children under five years old in Tripoli in 2016. The overall limited PCV13 vaccine coverage in this study highlighted the need for vaccines with greater coverage in the immunization programs in Lebanon. Longitudinal national studies investigating the carriage of pneumococci in children are required to further assess the impact of the PCV vaccine on pneumococci carriage in children and steer new vaccine development.

The role of the microbiota in respiratory virus-bacterial pathobiont relationships in the upper respiratory tract

The mechanisms by which respiratory viruses predispose to secondary bacterial infections remain poorly characterized. Using 2,409 nasopharyngeal swabs from 300 infants in Botswana, we performed a detailed analysis of factors that influence the dynamics of bacterial pathobiont colonization during infancy. We quantify the extent to which viruses increase the acquisition of Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae. We provide evidence of cooperative interactions between these pathobionts while identifying host characteristics and environmental exposures that influence the odds of pathobiont colonization during early life. Using 16S rRNA gene sequencing, we demonstrate that respiratory viruses result in losses of putatively beneficial Corynebacterium and Streptococcus species that are associated with a lower odds of pathobiont acquisition. These findings provide novel insights into viral-bacterial relationships in the URT of direct relevance to respiratory infections and suggest that the URT bacterial microbiota is a potentially modifiable mechanism by which viruses promote bacterial respiratory infections.