A multicenter study on the epidemiology of complicated parapneumonic effusion in the era of currently available pneumococcal conjugate vaccines

Bacterial Acute Otitis Media Complicated with Otorrhea in a Children's Hospital in the Era of Pneumococcal Conjugate Vaccines

Acute otitis media (AOM) is a common disease among children and can be complicated by otorrhea (AOMO). In 2010, the 13-valent Pneumococcal Conjugate Vaccine (PCV13) replaced the 7-valent vaccine (PCV7) in Greece. We aimed to describe the microbiological profile of bacterial ΑOMO among children younger than 16 years across the two PCV periods in a tertiary children's hospital. Middle ear fluid cultures from 2418 children with AOMO were collected from 2007 to 2022. Otopathogens were isolated and tested for antimicrobial susceptibility. Data were compared between the PCV7- (2007-2011) and PCV13-period (2012-2019). The most common otopathogen over the 16-year period was S. pyogenes (35.4%), followed by H. influenzae (33.8%), S. pneumoniae (26.6%), and M. catarrhalis (4.1%). Pneumococcal resistance to cefotaxime and clindamycin significantly increased from 2% to 4.5% (p = 0.019) and 16.1% to 22.8% (p = 0.039), respectively. Resistance of H. influenzae to ampicillin increased from 6.3% to 13.9% (p < 0.001). A significant reduction in cotrimoxazole-resistant S. pneumoniae from 31% to 22.4% (p = 0.012), and in clindamycin-resistant and erythromycin-resistant S pyogenes, from 17.4% to 9.3% and 21.4% to 10.8%, respectively (p ≤ 0.001), was observed. During 2013-2022, 38 S. pneumoniae serotypes were identified among 250 isolates. Serotype 3 (27.2%) and 19A (13.2%) prevailed, followed by 19F (7%). The most common causes after the shift to PCV13 are S. pyogenes and H. influenzae. However, S. pneumoniae remains an important otopathogen with significant antimicrobial resistance. Serotype 3 was mostly detected, followed by 19A.

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. When available the susceptibility of the isolates to antimicrobials was evaluated.

RESULTS

pIPD cases were markedly reduced in the last trimester of 2019-2020 and the entire 2020-2021 season. While 2021-2022 was in line with pre-pandemic seasons, in 2022-2023, the number of pIPD cases exceeded those found pre-pandemic. Molecular tests were responsible for identifying and serotyping 30% of cases, highlighting their importance in evaluating pIPD. Among the 316 pIPD cases, 37 different serotypes were detected, of which serotypes 3 (n = 85, 26.9%), 8 (n = 25, 7.9%), 10A (n = 21, 6.6%) and 24F (n = 20, 6.3%) were the most frequent. The post-pandemic serotype distribution reflected mostly pre-pandemic trends and the rebound was not driven by particular serotypes. We identified many vaccine failures, most (n = 37) representing serotype 3 infections. Penicillin non-susceptibility increased from 14% pre-pandemic to 29%, with serotype 24F becoming particularly significant.

CONCLUSIONS

The higher number of cases of pIPD post-COVID-19 in Portugal raises the possibility of a higher burden of pneumococcal disease in Europe post-pandemic. The relatively stable serotype distribution and the current availability of the higher valency conjugate vaccines PCV15 and PCV20, potentially preventing a large proportion of pIPD (43% and 67%, respectively), offer an opportunity to control this increase.