Vaccination with the 13-valent pneumococcal conjugate vaccine has consistently decreased the rate of community-acquired pneumonia among French children since its implementation in 2010, according to an analysis based on a prospective multicenter study published in JAMA Pediatrics.
The findings suggest that advances made with the vaccine in France have not been undercut by nonvaccine serotypes, a phenomenon that had been reported in other countries more than 5 years after the vaccine was introduced.
“Up to 4 years after PCV13 implementation, the frequency of invasive pneumococcal disease was strongly reduced worldwide,” Naïm Ouldali, MD, from the Association Clinique et Thérapeutique Infantile du Val-de-Marne, France, and colleagues wrote. “However, with a recent increase in its frequency owing to highly invasive non-PCV13 serotypes in England, Germany and Israel and in pneumococcal meningitis in France, the serotype replacement has raised concerns about the long-term outcome of PCV13 use beyond 5 years after its implementation.”
The researchers noted, however, that current trends in invasive pneumococcal disease cannot be extrapolated to community-acquired pneumonia (CAP).
Children treated in eight French pediatric EDs between June 2009 and May 2017 were included in a quasi-experimental, population-based, interrupted time-series analysis. All children were aged 15 years or younger and had a diagnosis of CAP confirmed by radiographic imaging.
Pleural effusion was observed in 673 of the 12,587 children diagnosed with CAP. Approximately one-third of patients diagnosed with CAP (n = 4,273) required hospitalization, and 1.8% of patients had CAP caused by pneumococcal infection. High levels of inflammatory biomarkers were observed in 2,379 cases of CAP (18.9%).
The researchers identified a “sharp” decrease in the frequency of CAP (–0.8% per month; 95% CI, –0.1% to –0.5%) — from 6.3 to 3.5 cases of CAP per 1,000 pediatric ED visits until May 2014. Then, starting in June 2014, the researchers saw a slight increase in CAP cases (0.9% per month; 95% CI, 0.4%-1.4%), rising to 3.8 cases per 1,000 pediatric ED visits in May 2017.
CAP with pleural effusion decreased immediately with PCV13 vaccination (–48%; 95% CI, –84% to –12%), along with CAP requiring hospitalization (–30%; 95% CI, –56% to –5%) and CAP with high levels of inflammatory biomarkers (–30%; 95% CI, –54% to –6%).
Ouldali and colleagues noted that the results contrast with the recent spike in invasive pneumococcal disease seen in several other countries during the same period linked to serotype replacement more than 5 years after PCV13 implementation.
“This difference in the trends suggests different consequences of serotype replacement on pneumococcal CAP vs. invasive pneumococcal disease,” the researchers wrote. “Moreover, no dominant serotype seems to have emerged, because after PCV13 implementation, none of the 11 non-PCV13 serotypes isolated in CAP were involved in more than four cases. The recent slight increase in the number of all CAP cases and virus involvement may reflect changes in the epidemiology of other pathogens and/or serotype replacement with less pathogenic serotypes.” – by Katherine Bortz
Disclosures: Ouldali reports receiving grants from GlaxoSmithKline. Please see the study for all other authors’ relevant financial disclosures.