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Please use this identifier to cite or link to this item: http://hdl.handle.net/10564/3725

Title: Environmental Presence and Genetic Characteristics of Carbapenemase-Producing Enterobacteriaceae from Hospital Sewage and River Water in the Philippines.
Other Titles: フィリピンの環境(病院排水・河川)より分離されたカルバペネマーゼ産生腸内細菌科の分子遺伝学的解析
Authors: Suzuki, Yuki
Nazareno, Pearl Joy
Nakano, Ryuichi
Mondoy, Melisa
Nakano, Akiyo
Bugayong, Mark Philip
Bilar, Josie
Perez, Mauricio 5th
Medina, Emarld Julian
Saito-Obata, Mariko
Saito, Mayuko
Nakashima, Kazutoshi
Oshitani, Hitoshi
Yano, Hisakazu
Keywords: Carbapenemase-producing Enterobacteriaceae
hospital sewage
river water
the Philippines
Issue Date: 7-Jan-2020
Publisher: American Society for Microbiology
Citation: Applied and environmental microbiology Vol.86 No.2 Article No.e01906-19 (2020 Jan)
Abstract: This study aimed to evaluate the prevalence and genetic characteristics of carbapenemase-producing Enterobacteriaceae (CPE) in hospital sewage and river water in the Philippines, which has a typical tropical maritime climate. We collected 83 water samples from 7 hospital sewage and 10 river water sites. CPE were identified using CHROMagar mSuperCARBA, and Gram-negative strains were identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) or 16S rRNA gene sequencing. Resistance genes in Enterobacteriaceae strains were identified using PCR and DNA sequencing, and transferability of carbapenemase genes from the CPE was investigated with conjugation experiments. Genotyping was performed using multilocus sequence typing (MLST) for Escherichia coli and Klebsiella pneumoniae Out of 124 Enterobacteriaceae isolates, we identified 51 strains as CPE and divided these into 7 species, 11 E. coli, 14 Klebsiella spp., 15 Enterobacter spp., and 11 others, including 4 additional species. Conjugation experiments via broth mating and using E. coli J53 revealed that 24 isolates can transfer carbapenemase-encoding plasmids. MLST analysis showed that 6 of 11 E. coli isolates belonged to clonal complex 10 (CC10). Of 11 K. pneumoniae strains, 9 unique sequence types (STs) were identified, including ST147. Five types of carbapenemase genes were identified, with the most prevalent being NDM (n = 39), which is epidemic in clinical settings in the Philippines. E. coli CC10 and K. pneumoniae ST147, which are often detected in clinical settings, were the dominant strains. In summary, our results indicate that hospital sewage and river water are contaminated by CPE strains belonging to clinically important clonal groups.IMPORTANCE Carbapenemase-producing Enterobacteriaceae (CPE) cause severe health care-associated infections, and their increasing prevalence is a serious concern. Recently, natural ecosystems have been recognized as important reservoirs of antibiotic resistance genes. We investigated the prevalence and genetic characteristics of CPE isolated from the environment (hospital sewage and river water) in the Philippines and found several CPE, including Escherichia coli and other species, with different carbapenemases. The most prevalent carbapenemase gene type was NDM, which is endemic in clinical settings. This study revealed that isolates belonging to carbapenemase-producing E. coli CC10 and K. pneumoniae sequence type 147 (ST147), which are often detected in clinical settings, were dominant in the natural environment. Our work here provides a report on the presence and characteristics of CPE in the environment in the Philippines and demonstrates that both hospital sewage and river water are contaminated by CPE strains belonging to clinically important clonal groups.
Description: 博士(医学)・甲第734号・令和2年3月16日
Copyright © 2020 Suzuki et al. This is an openaccess article distributed under the terms of the Creative Commons Attribution 4.0 International license (https://creativecommons.org/licenses/by/4.0/).
URI: http://hdl.handle.net/10564/3725
ISSN: 00992240
Academic Degrees and number: 24601A734
Degree-granting date: 2020-03-16
Degree name: 博士(医学)
Degree-granting institutions: 奈良県立医科大学
Appears in Collections:2019年度

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