title: Predictors of blaCTX-M-15 in varieties of Escherichia coli genotypes from humans in community settings in Mwanza, Tanzania.
abstract: BACKGROUND
  Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae commonly cause infections worldwide. Bla CTX-M-15 has been commonly detected in hospital isolates in Mwanza, Tanzania. Little is known regarding the faecal carriage of ESBL isolates and bla CTX-M-15 allele among humans in the community in developing countries.
  
  
  METHODS
  A cross-sectional study involving 334 humans from the community settings in Mwanza City was conducted between June and September 2014. Stool specimens were collected and processed to detect ESBL producing enterobacteriaceae. ESBL isolates were confirmed using disc approximation method, commercial ESBL plates and VITEK-2 system. A polymerase chain reaction and sequencing based allele typing for CTX-M ESBL genes was performed to 42 confirmed ESBL isolates followed by whole genome sequence of 25 randomly selected isolates to detect phylogenetic groups, sequence types plasmid replicon types.
  
  
  RESULTS
  Of 334 humans investigated, 55 (16.5 %) were found to carry ESBL-producing bacteria. Age, history of antibiotic use and history of admission were independent factors found to predict ESBL-carriage. The carriage rate of ESBL-producing Escherichia coli was significantly higher than that of Klebsiella pneumoniae (15.1 % vs. 3.8 %, p = 0.026). Of 42 ESBL isolates, 37 (88.1 %) were found to carry the bla CTX-M-15 allele. Other transferrable resistance genes were aac(6')Ib-cr, aac(3)-IIa, aac(3)-IId, aadA1, aadA5, strA, strB and qnrS1. Eight multi-locus sequence types (ST) were detected in 25 E. coli isolates subjected to genome sequencing. ST-131 was detected in 6 (24 %), ST-38 in 5 (20 %) and 5 (20 %) clonal complex - 10(ST-617, ST-44) of isolates. The pathogenic phylogenetic groups D and B2 were detected in 8/25 (32 %) and 6/25 (24 %) of isolates respectively. BlaCTX-M-15 was found to be located in multiple IncY and IncF plasmids while in 13/25(52 %) of cases it was chromosomally located.
  
  
  CONCLUSIONS
  The overlap of multi-drug resistant bacteria and diversity of the genotypes carrying CTX-M-15 in the community and hospitals requires an overall approach that addresses social behaviour and activity, rationalization of the antibiotic stewardship policy and a deeper understanding of the ecological factors that lead to persistence and spread of such alleles.
authors.affiliation: Department of Microbiology/Immunology Weill Bugando School of Medicine, Catholic University of Health and Allied Sciences, BOX 1464, Mwanza, Tanzania. mshana72@yahoo.com.
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Mshana
authors.affiliation: Institute of Medical Microbiology, Justus-Liebig University, Schubertstrasse 81, 35392, Giessen, Germany.|Germany and German Center for Infection Research DZIF, Partner site Giessen-Marburg-Langen, Campus Giessen, Giessen, Germany.
authors.forename: Linda
authors.initials: L
authors.lastname: Falgenhauer
authors.affiliation: Department of Microbiology/Immunology Weill Bugando School of Medicine, Catholic University of Health and Allied Sciences, BOX 1464, Mwanza, Tanzania.
authors.forename: Mariam M
authors.initials: MM
authors.lastname: Mirambo
authors.affiliation: Department of Microbiology/Immunology Weill Bugando School of Medicine, Catholic University of Health and Allied Sciences, BOX 1464, Mwanza, Tanzania.
authors.forename: Martha F
authors.initials: MF
authors.lastname: Mushi
authors.affiliation: Department of Microbiology/Immunology Weill Bugando School of Medicine, Catholic University of Health and Allied Sciences, BOX 1464, Mwanza, Tanzania.
authors.forename: Nyambura
authors.initials: N
authors.lastname: Moremi
authors.affiliation: Department of Microbiology/Immunology Weill Bugando School of Medicine, Catholic University of Health and Allied Sciences, BOX 1464, Mwanza, Tanzania.
authors.forename: Rechel
authors.initials: R
authors.lastname: Julius
authors.affiliation: Department of Microbiology/Immunology Weill Bugando School of Medicine, Catholic University of Health and Allied Sciences, BOX 1464, Mwanza, Tanzania.
authors.forename: Jeremiah
authors.initials: J
authors.lastname: Seni
authors.affiliation: Institute of Medical Microbiology, Justus-Liebig University, Schubertstrasse 81, 35392, Giessen, Germany.|Germany and German Center for Infection Research DZIF, Partner site Giessen-Marburg-Langen, Campus Giessen, Giessen, Germany.
authors.forename: Can
authors.initials: C
authors.lastname: Imirzalioglu
authors.affiliation: Department of Microbiology/Immunology, Muhimbili University of Health and Allied Sciences, BOX 65001, Dar es Salaam, Tanzania.
authors.forename: Mecky
authors.initials: M
authors.lastname: Matee
authors.affiliation: Institute of Medical Microbiology, Justus-Liebig University, Schubertstrasse 81, 35392, Giessen, Germany.|Germany and German Center for Infection Research DZIF, Partner site Giessen-Marburg-Langen, Campus Giessen, Giessen, Germany.
authors.forename: Trinad
authors.initials: T
authors.lastname: Chakraborty
mesh_terms: D000293:Adolescent; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D024881:Drug Resistance, Bacterial / Q000235:genetics; D004755:Enterobacteriaceae / Q000235:genetics / Q000302:isolation & purification; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000382:microbiology; D029968:Escherichia coli Proteins / Q000235:genetics*; D005260:Female; D005838:Genotype; D006761:Hospitals; D006801:Humans; D007710:Klebsiella Infections / Q000188:drug therapy / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000235:genetics* / Q000302:isolation & purification; D008297:Male; D008826:Microbial Sensitivity Tests; D010802:Phylogeny; D010957:Plasmids; D012423:Rural Health; D013636:Tanzania; D055815:Young Adult; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D029968:Escherichia coli Proteins; D001618:beta-Lactamases