title: Predominance of CTX-M-15 among ESBL Producers from Environment and Fish Gut from the Shores of Lake Victoria in Mwanza, Tanzania.
abstract: Extended-Spectrum Beta-Lactamase (ESBL)-producing bacteria are a common cause of healthcare and community-associated infections worldwide. The distribution of such isolates in the environment and their presence in fish as a result of sewage contamination is not well-studied. Here we examined fish and environmental samples from Mwanza city for the presence of ESBL-producing bacteria. From 196 fish sampled from local markets, 26 (13.3%) contained lactose-fermenting ESBL-producing bacteria, while 39/73 (53.4%) environmental samples from the same area were ESBL producers. Antibiotic resistance genes, multi locus sequence types (MLST) and plasmid replicon types in 24 selected isolates from both populations were identified with whole genome sequencing using Illumina MiSeq. Nine of eleven sequenced fish isolates had theblaCTX-M-15gene whereas 12/13 from environment carriedblaCTX-M-15. Antibiotic resistance genes encoding resistance to sulfonamides (sul1/sul2), tetracyclines [tet(A)/tet(B)] fluoroquinolones [e.g.,aac(6')-Ib-cr,qnrS1], aminoglycosides [e.g.,aac(3)-lld, strB,strA,] and trimethoprim (e.g.,dfrA14) were detected.E. colisequence type ST-38 (2) and ST-5173 (2) were detected in isolates both from the environment and fish. IncY plasmids carryingblaCTX-M-15,qnrS1,strA, andstrB were detected in five environmentalE. coliisolates and in oneE. coliisolate from fish. Our data indicate spillage of resistant environmental isolates into Lake Victoria through the sewage system. Persistence ofblaCTX-M-15in the Mwanza city environment is complex, and involves both clonal spread of resistant strains as well as dissemination by commonly occurring IncY plasmids circulating in isolates present in humans, the environment as well as in the food chain.
authors.affiliation: Department of Microbiology and Immunology, Weill Bugando School of Medicine Mwanza, Tanzania.
authors.forename: Nyambura
authors.initials: N
authors.lastname: Moremi
authors.affiliation: Department of Microbiology and Immunology, Weill Bugando School of Medicine Mwanza, Tanzania.
authors.forename: Elizabeth V
authors.initials: EV
authors.lastname: Manda
authors.affiliation: Institute of Medical Microbiology, Justus Liebig UniversityGiessen, Germany; German Center for Infection Research, Partner site Giessen-Marburg-Langen, Campus GiessenGiessen, Germany.
authors.forename: Linda
authors.initials: L
authors.lastname: Falgenhauer
authors.affiliation: Institute of Medical Microbiology, Justus Liebig UniversityGiessen, Germany; German Center for Infection Research, Partner site Giessen-Marburg-Langen, Campus GiessenGiessen, Germany.
authors.forename: Hiren
authors.initials: H
authors.lastname: Ghosh
authors.affiliation: Institute of Medical Microbiology, Justus Liebig UniversityGiessen, Germany; German Center for Infection Research, Partner site Giessen-Marburg-Langen, Campus GiessenGiessen, Germany.
authors.forename: Can
authors.initials: C
authors.lastname: Imirzalioglu
authors.affiliation: Department of Microbiology/Immunology, Muhimbili University of Health and Allied Sciences Dar es Salaam, Tanzania.
authors.forename: Mecky
authors.initials: M
authors.lastname: Matee
authors.affiliation: Institute of Medical Microbiology, Justus Liebig UniversityGiessen, Germany; German Center for Infection Research, Partner site Giessen-Marburg-Langen, Campus GiessenGiessen, Germany.
authors.forename: Trinad
authors.initials: T
authors.lastname: Chakraborty
authors.affiliation: Department of Microbiology and Immunology, Weill Bugando School of Medicine Mwanza, Tanzania.
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Mshana
keywords: blaCTX-M-15; environment; fish