Evolution of Antimicrobial Susceptibility to Penicillin in Invasive Strains of Streptococcus pneumoniae during 2007–2021 in Madrid, Spain

Abstract

The use of pneumococcal conjugate vaccines has affected the epidemiology and distribution of Streptococcus pneumoniae serotypes causing Invasive Pneumococcal Disease (IPD). The aim of this study was to analyze the evolution of the phenotypical profiles of antimicrobial susceptibility to penicillin (PEN) in all IPD strains isolated in Madrid, Spain, during 2007–2021. In total, 7133 invasive clinical isolates were characterized between 2007 and 2021. Levels of PENR and PNSSDR were 2.0% and 24.2%, respectively. In addition, 94.4% of all the PENR belonged to four serotypes, including 11A (33.6%), 19A (30.8%), 14 (20.3%) and 9V (9.8%). All the strains of serotype 11A, which is a non-PCV13 serotype, were detected after the year 2011. Serotypes 6C, 15A, 23B, 24F, 35B, 19F, 16F, 6B, 23F, 24B, 24A, 15F and a limited number of strains of serogroups 16 and 24 (non-typed at serotype level) were associated with PNSSDR (p < 0.05). PNSSDR strains of non-PCV13 serotypes 11A, 24F, 23B, 24B, 23A and 16F were more frequent from 2014 to 2021. The changes in S. pneumoniae serotype distribution associated with the use of conjugate vaccines had caused in our region the emergence of non-PCV13 pneumococcal strains with different PENR or PNSSDR patterns. The emergence of serotype 11A resistant to penicillin as the most important non-PCV13 serotype is a worrisome event with marked relevance from the clinical and epidemiological perspective.

Evolution of the serotypes causing invasive pneumococcal disease along 2008-2022 in a Level 2 Public Hospital of the Madrid Region, in relation to their inclusion in different conjugate vaccines

“…No obstante, en este último periodo (2018-2022), como ya se ha comentado también comienza a observarse un aumento del serotipo 11A. Este serotipo está actualmente asociado con resistencia a penicilina [ 15 , 20 ].…”

“…El aumento significativo de los serotipos cubiertos por la vacuna en desarrollo VNC21 puede reflejar un efecto de reemplazo por serotipos no cubiertos hasta el momento por este tipo de vacunas. El cambio en el calendario tualmente asociado con resistencia a penicilina [15,20].…”

A Four Years Longitudinal Study of Childhood Vaccination Trends and Supply Chain Resilience in Tanzania amid COVID-19 Pandemic

“…PCV is widely used in Tanzania and sub-Saharan Africa with populations of children who have sickle cell disease (SCD) [18][19][20]. Antibiotic resistance to antibiotics used to treat pneumococcal infections in these children has increased, leaving the PCV as a viable option to improve survival in children with SCD [21,22].…”