Epidemiological characteristics of nasopharyngeal Streptococcus pneumoniae strains among children with pneumonia in Chongqing, China

Abstract

Streptococcus pneumoniae (pneumococcus) is the most common respiratory pathogen worldwide. Nasopharyngeal carriage with S . pneumoniae is the major source of lower respiratory tract infection and horizontal spread among children. Investigating nasopharyngeal S . pneumoniae is crucial for clinicians to control pneumococcus disease. Here, we retrospectively analyzed clinical information of 5,960 hospitalized children, focusing on pneumonia children less than five years with positive nasopharyngeal pneumococcal cultures. Nasopharyngeal aspirates (NPAs) were collected between June 2009 and December 2016, which were outside the pneumococcal conjugate vaccine(PCV) period. NPAs were subjected to common bacterial culture and antibiotic susceptibility tests, and serotypes were identified by both multiplex PCR and DNA sequencing. Results clearly revealed that clinical manifestations of the children whose NPAs were S . pneumoniae culture positive were serious, especially in those less than twelve months old. Fifteen different serotypes of nasopharyngeal S . pneumoniae were detected, the most common ones being 19F (35.2%), 6A/B (23.8%), 19A (11.4%), 15B/C (9.3%) and 23F (7.8%). Eight serotypes, accounting for 85.5% of the isolates, corresponded to the PCV13 serotypes. Approximately one-third of all S . pneumoniae strains were susceptible to penicillin. Overall, we consider nasopharyngeal S . pneumoniae culture is beneficial in assessing the situations of pneumonia children. Moreover, PCV13 could be useful in preventing pneumococcal disease in Chongqing, China.

Pneumococcal Carriage, Serotype Distribution, and Risk Factors in Children With Community-Acquired Pneumonia, 5 Years After Introduction of the 10-Valent Pneumococcal Conjugate Vaccine in Ethiopia

“…Our findings were lower than results from a similar study in Mozambique (45.1%) [21], which was performed 1 to 3 years after introduction of PCV10 in the country. However, our results were higher than results from a similar study in China (17.3%) [22] performed before the introduction of PCV in the country using nasopharyngeal aspirate cultures.…”

Molecular epidemiology of Streptococcus pneumoniae isolated from pediatric community-acquired pneumonia in pre-conjugate vaccine era in Western China

“…A good consistency between pneumococcal serotypes and STs was revealed in this study using the correspondence analysis. The consistency was also reported in previous studies, mostly in China [ 11 , 32 , 34 , 39 ].…”

“…Based on these findings, the vaccine immunization and protection effect could not entirely explain the emergence and dissemination of MDR-related serotypes of 19A and 19F, which related to the homogeneous genetic background of CC271 in Asian countries [ 31 ]. Evidence from multicenter surveillance in China demonstrated that 84.7% of the isolates of 19A and 19F belonged to CC271 [ 33 ], suggesting that in the area of where PCV7 vaccination rate of less than 10%, the vaccine implication pressure could not entirely explain these phenomenon, and other risk factors (such as antibiotic use and younger age) may promote the dissemination of these isolates among children suffering from CAP [ 34 ]. Our data suggest that the PCV13 coverage rate was 87.3% for all the MDR isolates, indicating that the PCV13 may have a potential benefit to reduce the spread of MDR isolates.…”

Upper respiratory tract colonization withStreptococcus pneumoniaein adults

“…DNA-based approaches have also been developed for detection and serotyping, including microarray, sequencing, and traditional or quantitative PCR (qPCR) [73][74][75].…”

“…In summary, most contemporary investigations of pneumococcal respiratory tract carriage have been conducted in children [11][12][13][37][38][39][40][41][42]. In children, it is recommended that a single nasopharyngeal swab be collected for culture-based pneumococcal carriage detection and serotyping using the capsular reaction/swelling test [70]; DNA-based approaches with high sensitivity are also available for detection and serotyping [15,36,[73][74][75][76]…”