title: Changes in the incidence of Streptococcus pneumoniae bacteremia and its serotypes over 10 years in one hospital in South Korea.
abstract: Here, we examined the distribution of pneumococcal serotypes and the antibiotic susceptibility of Streptococcus pneumoniae in clinical blood isolates. The serotypes of 91 S. pneumoniae blood isolates, collected from January 2003 to March 2014, were identified by multiplex PCR and sequencing. The most common serotypes were 19F, 19A, 3, 4, and 14, accounting for 53.8% of the total. The serotype coverage rates of pneumococcal conjugated vaccine (PCV) 7, PCV10, and PCV13 were different during three test periods: 38.7%, 70.9%, and 93.5% in period I (2003-2005), 46.8%, 50.0%, and 75.0% in period II (2006-2008), and 28.5%, 32.1%, and 64.2% in period III (2009-2014), respectively. By contrast, the number of non-PCV13 serotypes increased from 6.4% in period I to 25% and 35.7% in periods II and III, respectively. The susceptibility of non-PCV13 serotypes to antimicrobial agents (penicillin, erythromycin, cefotaxime, and meropenem) was higher than that of PCV serotypes. In particular, non-PCV13 serotypes showed 100% and 95% susceptibility to penicillin and cefotaxime, respectively. Serotypes 19A and 19F showed high prevalence (79.1%) among 24 multi-drug resistant (MDR) isolates. Notably, all serotype 19A isolates were MDR. From January 2003 to March 2014, the proportion of non-PCV13 serotype pneumococci in blood isolates increased whereas the coverage rate of PCV13 decreased. Effective pneumococcal vaccines are required to protect against MDR serotype 19A isolates and the increasing number of non-PCV13 serotypes.
authors.affiliation: Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, South Korea.
authors.forename: Miey
authors.initials: M
authors.lastname: Park
authors.affiliation: Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, South Korea.
authors.forename: Han-Sung
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, South Korea.
authors.forename: Kyu Sung
authors.initials: KS
authors.lastname: Shin
authors.affiliation: Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, South Korea.
authors.forename: Hyun Soo
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, South Korea.
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Park
authors.affiliation: Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, South Korea.
authors.forename: Wonkeun
authors.initials: W
authors.lastname: Song
authors.affiliation: Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, South Korea.
authors.forename: Hyoun Chan
authors.initials: HC
authors.lastname: Cho
authors.affiliation: Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, South Korea.
authors.forename: Kyu Man
authors.initials: KM
authors.lastname: Lee
authors.affiliation: Department of Laboratory Medicine, Hallym University College of Medicine, Seoul, South Korea. Electronic address: jaeseokcp@gmail.com.
authors.forename: Jae-Seok
authors.initials: JS
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D016470:Bacteremia / Q000453:epidemiology / Q000382:microbiology; D002648:Child; D002675:Child, Preschool; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011008:Pneumococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D016133:Polymerase Chain Reaction; D056910:Republic of Korea / Q000453:epidemiology; D065288:Serogroup; D013296:Streptococcus pneumoniae / Q000145:classification*
keywords: Multi-drug resistant (MDR) isolates; Non-PCV13 serotypes; Pneumococcal conjugated vaccine; Serotypes; Streptococcus pneumoniae