scholarly journals Determining the Virulence Properties of Escherichia coli ST131 Containing Bacteriocin-Encoding Plasmids Using Short- and Long-Read Sequencing and Comparing Them with Those of Other E. coli Lineages

2019 ◽  
Vol 7 (11) ◽  
pp. 534 ◽  
Author(s):  
da Cruz Campos ◽  
Cavallo ◽  
L. Andrade ◽  
van Dijl ◽  
Couto ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Multidrug Resistant ◽  
Transmission Range ◽  
E Coli ◽  
Colicin E1 ◽  
Long Read ◽  
Tract Infections ◽  
Type Strains ◽  
Highly Virulent ◽  
Adhesion And Invasion

Escherichia coli ST131 is a clinical challenge due to its multidrug resistant profile and successful global spread. They are often associated with complicated infections, particularly urinary tract infections (UTIs). Bacteriocins play an important role to outcompete other microorganisms present in the human gut. Here, we characterized bacteriocin-encoding plasmids found in ST131 isolates of patients suffering from a UTI using both short- and long-read sequencing. Colicins Ia, Ib and E1, and microcin V, were identified among plasmids that also contained resistance and virulence genes. To investigate if the potential transmission range of the colicin E1 plasmid is influenced by the presence of a resistance gene, we constructed a strain containing a plasmid which had both the colicin E1 and blaCMY-2 genes. No difference in transmission range was found between transformant and wild-type strains. However, a statistically significantly difference was found in adhesion and invasion ability. Bacteriocin-producing isolates from both ST131 and non-ST131 lineages were able to inhibit the growth of other E. coli isolates, including other ST131. In summary, plasmids harboring bacteriocins give additional advantages for highly virulent and resistant ST131 isolates, improving the ability of these isolates to compete with other microbiota for a niche and thereby increasing the risk of infection.

scholarly journals Three-Year Trend in Escherichia coli Antimicrobial Resistance among Children’s Urine Cultures in an Italian Metropolitan Area

Children ◽  
2021 ◽  
Vol 8 (7) ◽  
pp. 597
Author(s):  
Luca Pierantoni ◽  
Laura Andreozzi ◽  
Simone Ambretti ◽  
Arianna Dondi ◽  
Carlotta Biagi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Metropolitan Area ◽  
Bacterial Infections ◽  
Asymptomatic Bacteriuria ◽  
Multidrug Resistant ◽  
Resistance Rate ◽  
First Line ◽  
E Coli ◽  
First Line Therapy ◽  
Tract Infections

Urinary tract infections (UTIs) are among the most common bacterial infections in children, and Escherichia coli is the main pathogen responsible. Several guidelines, including the recently updated Italian guidelines, recommend amoxicillin-clavulanic acid (AMC) as a first-line antibiotic therapy in children with febrile UTIs. Given the current increasing rates of antibiotic resistance worldwide, this study aimed to investigate the three-year trend in the resistance rate of E. coli isolated from pediatric urine cultures (UCs) in a metropolitan area of northern Italy. We conducted a retrospective review of E. coli-positive, non-repetitive UCs collected in children aged from 1 month to 14 years, regardless of a diagnosis of UTI, catheter colonization, urine contamination, or asymptomatic bacteriuria. During the study period, the rate of resistance to AMC significantly increased from 17.6% to 40.2% (p < 0.001). Ciprofloxacin doubled its resistance rate from 9.1% to 16.3% (p = 0.007). The prevalence of multidrug-resistant E. coli rose from 3.9% to 9.2% (p = 0.015). The rate of resistance to other considered antibiotics remained stable, as did the prevalence of extended spectrum beta-lactamases and extensively resistant E. coli among isolates. These findings call into question the use of AMC as a first-line therapy for pediatric UTIs in our population, despite the indications of recent Italian guidelines.

scholarly journals Comparative Genomics ofEscherichia coliIsolated from Skin and Soft Tissue and Other Extraintestinal Infections

mBio ◽  
2017 ◽  
Vol 8 (4) ◽  
Author(s):  
Amit Ranjan ◽  
Sabiha Shaik ◽  
Nishant Nandanwar ◽  
Arif Hussain ◽  
Sumeet K. Tiwari ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Comparative Genomics ◽  
Soft Tissue ◽  
Multidrug Resistant ◽  
Primary Concern ◽  
Beta Lactamase ◽  
Soft Tissue Infections ◽  
E Coli ◽  
Recent Emergence ◽  
Tract Infections

ABSTRACTEscherichia coli, an intestinal Gram-negative bacterium, has been shown to be associated with a variety of diseases in addition to intestinal infections, such as urinary tract infections (UTIs), meningitis in neonates, septicemia, skin and soft tissue infections (SSTIs), and colisepticemia. Thus, for nonintestinal infections, it is categorized as extraintestinal pathogenicE. coli(ExPEC). It is also an opportunistic pathogen, causing cross infections, notably as an agent of zoonotic diseases. However, comparative genomic data providing functional and genetic coordinates for ExPEC strains associated with these different types of infections have not proven conclusive. In the study reported here, ExPECE. coliisolated from SSTIs was characterized, including virulence and drug resistance profiles, and compared with isolates from patients suffering either pyelonephritis or septicemia. Results revealed that the majority of the isolates belonged to two pathogenic phylogroups, B2 and D. Approximately 67% of the isolates were multidrug resistant (MDR), with 85% producing extended-spectrum beta-lactamase (ESBL) and 6% producing metallo-beta-lactamase (MBL). TheblaCTX-M-15genotype was observed in at least 70% of theE. coliisolates in each category, conferring resistance to an extended range of beta-lactam antibiotics. Whole-genome sequencing and comparative genomics of the ExPEC isolates revealed that two of the four isolates from SSTIs, NA633 and NA643, belong to pandemic sequence type ST131, whereas functional characteristics of three of the ExPEC pathotypes revealed that they had equal capabilities to form biofilm and were resistant to human serum. Overall, the isolates from a variety of ExPEC infections demonstrated similar resistomes and virulomes and did not display any disease-specific functional or genetic coordinates.IMPORTANCEInfections caused by extraintestinal pathogenicE. coli(ExPEC) are of global concern as they result in significant costs to health care facilities management. The recent emergence of a multidrug-resistant pandemic clone,Escherichia coliST131, is of primary concern as a global threat. In developing countries, such as India, skin and soft tissue infections (SSTIs) associated withE. coliare marginally addressed. In this study, we employed both genomic analysis and phenotypic assays to determine relationships, if any, among the ExPEC pathotypes. Similarity between antibiotic resistance and virulence profiles was observed, ST131 isolates from SSTIs were reported, and genomic similarities among strains isolated from different disease conditions were detected. This study provides functional molecular infection epidemiology insight into SSTI-associatedE. colicompared with ExPEC pathotypes.

scholarly journals Phenotypic and Molecular Detection of Resistance Genes from Multi-drug Resistant Escherichia coli Isolated from Patients Attending Selected Hospitals in Damaturu, Yobe State, Nigeria

2021 ◽  
Vol 8 (9) ◽  
pp. 396-407
Author(s):  
Sheriff Wakil ◽  
Mustafa Alhaji Isa ◽  
Adam Mustapa
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Urinary Tract Infections ◽  
Resistance Genes ◽  
Molecular Detection ◽  
Multidrug Resistant ◽  
Clinical Samples ◽  
E Coli ◽  
Resistant Genes ◽  
Tract Infections

Multidrug resistance among Escherichia coli causing urinary tract infections (UTIs) and diarrhea are major public health problem worldwide which cause difficulty in treating the infections caused by Escherichia coli due to the high resistances. The study is aimed to determine the phenotypic and molecular detection of multidrug resistant E. coli isolated from clinical samples of patients attending selected Hospitals in Damaturu, Yobe State-Nigeria. Methods: Two hundred (200) clinical samples were collected aseptically from patient diagnosed with (100 stool samples) and UTI’s (100 urine samples) using sterile universal container. The samples were processed using standard microbiological methods for identification of E. coli. Samples were cultured on MacConkey agar (stool) and Cystine lactose electrolyte deficient agar (urine). The resulting colonies of isolates were further subculture on Eosin methylene blue agar for confirmatory and followed by gram stain, biochemical identification at Microbiology laboratory unit of Yobe State Specialist and Yobe State Teaching Hospital respectively. The antimicrobial susceptibility patterns were determined using Kirby-Bauer disc diffusion techniques and the phenotypic expression of extended spectrum beta-lactamases (ESBLs) were determined using modified double disc synergy test (MDDST) and also the three (3) resistance genes (blaTEM, accC1 and qnrA) were detected using polymerase chain reaction. Results: One hundred and twenty-two (122) isolates were resistant to antibiotics. The highest level of resistance was against amoxicillin (90.2%) while the least resistance was against sparfloxacin (24.3%). Thirty-seven (37) E. coli isolates shows MDR; the highest MDR was (24.3%) while least MDR was (5.4%). The PCR amplification of resistant genes (blaTEM, accC1 and qnrA) were detected on E. coli that shows positive ESBL and the bands were separated using agarose gel electrophoresis. Conclusion: The findings of this study show augmentin, ciprofloxacin and sparfloxacin are the most effective antibiotics against E. coli isolated from patients attending the two hospitals in Damaturu; who are diagnose with UTI and diarrheic infection. The resistant genes include; blaTEM, accC1 and qnrA coding for beta-lactam, aminoglycoside and quinolones were present in E. coli isolated from patients attending selected Hospitals in Yobe State, Nigeria. Keywords: Multidrug resistant, Escherichia coli, extended spectrum beta lactamase, resistance-associated genes, urinary tract infections, diarrheic.

scholarly journals Characterization of auto-agglutinating and non-typeable uropathogenic Escherichia coli strains

2019 ◽  
Vol 13 (06) ◽  
pp. 465-472
Author(s):  
Ulises Hernández-Chiñas ◽  
Alejandro Pérez-Ramos ◽  
Laura Belmont-Monroy ◽  
María E Chávez-Berrocal ◽  
Edgar González-Villalobos ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Genes ◽  
Antimicrobial Agents ◽  
Multidrug Resistant ◽  
Uropathogenic Escherichia Coli ◽  
E Coli ◽  
Resistant Strains ◽  
Tract Infections ◽  
Disk Method

Introduction: Uropathogenic Escherichia coli (UPEC) are the main etiological agent of urinary tract infections (UTIs). Association between different serotypes and UTIs is known, however, some strains are incapable to be serotyped. The aim of this work was to study bthe phenotypical and genotypical characteristics of 113 non-typeable (NT) and auto-agglutinating (AA) E. coli strains, isolated from UTIs in children and adults. Methodology: The 113 UPEC strains were analyzed by PCR assays using specific primers to determine their serogroups, fimH, papC, iutA, sat, hlyCA and cnf1, virulence associated genes, and chuA, yjaA and TSPE4.C2 for phylogroup determination. Additionally, the diffusion disk method was performed to evaluate the antimicrobial resistance to 18 antimicrobial agents. Results: Using the PCR assay, 63% (71) of the strains were genotyped showing O25 and O75 as the most common serogroups. The virulence genes fimH (86%) and iutA (74%) were the most prevalent, in relation to the phylogroups the commensal (A and B1) and virulent (B2 and D) showed similar frequencies (P > 0.05). The antimicrobial susceptibility test showed a high percentage (73%) of multidrug-resistant strains. Conclusions: The genotyping allowed identifying the serogroup in many of the strains that could not be typed by traditional serology. The strains carried virulence genes and were multidrug-resistant in both, commensal and virulent phylogroups. Our findings revealed that, in addition to the classical UPEC serogroups, there are pathogenic serogroups not reported yet.

scholarly journals Clonal Structure, Virulence Factor-encoding Genes and Antibiotic Resistance of Escherichia coli, Causing Urinary Tract Infections and Other Extraintestinal Infections in Humans in Spain and France during 2016

Antibiotics ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 161 ◽  
Author(s):  
Saskia-Camille Flament-Simon ◽  
Marie-Hélène Nicolas-Chanoine ◽  
Vanesa García ◽  
Marion Duprilot ◽  
Noémie Mayer ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Virulence Factor ◽  
Multidrug Resistant ◽  
Clonal Structure ◽  
Extended Spectrum Beta Lactamase ◽  
E Coli ◽  
Tract Infections ◽  
Encoding Genes ◽  
Sequence Types

Escherichia coli is the main pathogen responsible for extraintestinal infections. A total of 196 clinical E. coli consecutively isolated during 2016 in Spain (100 from Lucus Augusti hospital in Lugo) and France (96 from Beaujon hospital in Clichy) were characterized. Phylogroups, clonotypes, sequence types (STs), O:H serotypes, virulence factor (VF)-encoding genes and antibiotic resistance were determined. Approximately 10% of the infections were caused by ST131 isolates in both hospitals and approximately 60% of these infections were caused by isolates belonging to only 10 STs (ST10, ST12, ST58, ST69, ST73, ST88, ST95, ST127, ST131, ST141). ST88 isolates were frequent, especially in Spain, while ST141 isolates significantly predominated in France. The 23 ST131 isolates displayed four clonotypes: CH40-30, CH40-41, CH40-22 and CH40-298. Only 13 (6.6%) isolates were carriers of extended-spectrum beta-lactamase (ESBL) enzymes. However, 37.2% of the isolates were multidrug-resistant (MDR). Approximately 40% of the MDR isolates belonged to only four of the dominant clones (B2-CH40-30-ST131, B2-CH40-41-ST131, C-CH4-39-ST88 and D-CH35-27-ST69). Among the remaining MDR isolates, two isolates belonged to B2-CH14-64-ST1193, i.e., the new global emergent MDR clone. Moreover, a hybrid extraintestinal pathogenic E.coli (ExPEC)/enteroaggregative isolate belonging to the A-CH11-54-ST10 clone was identified.

scholarly journals Genomic Analysis of a Novel Phage Infecting the Turkey Pathogen Escherichia coli APEC O78 and Its Endolysin Activity

Viruses ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1034
Author(s):  
Sangsang Deng ◽  
Qiang Xu ◽  
Yajuan Fu ◽  
Leiqin Liang ◽  
Yan Wu ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Gene Annotation ◽  
Gc Content ◽  
Multidrug Resistant ◽  
Dimensional Structure ◽  
Resistant Bacteria ◽  
Local Alignment ◽  
Glycoside Hydrolase Family ◽  
E Coli ◽  
Tract Infections

Due to the increasing spread of multidrug-resistant (MDR) bacteria, phage therapy is considered one of the most promising methods for addressing MDR bacteria. Escherichia coli lives symbiotically in the intestines of humans and some animals, and most strains are beneficial in terms of maintaining a healthy digestive tract. However, some E. coli strains can cause serious zoonotic diseases, including diarrhea, pneumonia, urinary tract infections, and hemolytic uremic syndrome. In this study, we characterized a newly isolated Myoviridae phage, vB_EcoM_APEC. The phage vB_EcoM_APEC was able to infect E. coli APEC O78, which is the most common MDR E. coli serotype in turkeys. Additionally, the phage’s host range included Klebsiella pneumoniae and other E. coli strains. The genome of phage vB_EcoM_APEC (GenBank accession number MT664721) was 35,832 bp in length, with 52 putative open reading frames (ORFs) and a GC content of 41.3%. The genome of vB_EcoM_APEC exhibited low similarity (79.1% identity and 4.0% coverage) to the genome of Acinetobacter phage vB_AbaM_IME284 (GenBank no. MH853787.1) according to the nucleotide Basic Local Alignment Search Tool (BLASTn). Phylogenetic analysis revealed that vB_EcoM_APEC was a novel phage, and its genome sequence showed low similarity to other available phage genomes. Gene annotation indicated that the protein encoded by orf11 was an endolysin designated as LysO78, which exhibited 64.7% identity (91.0% coverage) with the putative endolysin of Acinetobacter baumannii phage vB_AbaM_B9. The LysO78 protein belongs to glycoside hydrolase family 19, and was described as being a chitinase class I protein. LysO78 is a helical protein with 12 α-helices containing a large domain and a small domain in terms of the predicted three-dimensional structure. The results of site-directed mutagenesis indicated that LysO78 contained the catalytic residues E54 and E64. The purified endolysin exhibited broad-spectrum bacteriolytic activity against Gram-negative strains, including the genera Klebsiella, Salmonella, Shigella, Burkholderia, Yersinia, and Pseudomonas, as well as the species Chitinimonas arctica, E. coli, Ralstonia solanacearum, and A. baumannii. An enzymatic assay showed that LysO78 had highly lytic peptidoglycan hydrolases activity (64,620,000 units/mg) against E. coli APEC O78, and that LysO78 had lytic activity in the temperature range of 4–85 °C, with an optimal temperature of 28 °C and optimal pH of 8.0, and was active at pH 3.0–12.0. Overall, the results suggested that LysO78 might be a promising therapeutic agent for controlling MDR E. coli APEC O78 and nosocomial infections caused by multidrug-resistant bacteria.

scholarly journals Genomic Insights into a Colistin-Resistant Uropathogenic Escherichia coli Strain of O23:H4-ST641 Lineage Harboring mcr-1.1 on a Conjugative IncHI2 Plasmid from Egypt

2021 ◽  
Vol 9 (4) ◽  
pp. 799
Author(s):  
Azza S. Zakaria ◽  
Eva A. Edward ◽  
Nelly M. Mohamed
Keyword(s):  
Escherichia Coli ◽  
Multidrug Resistant ◽  
Coli Strain ◽  
Colistin Resistance ◽  
E Coli ◽  
Agriculture Sector ◽  
Potential Reservoir ◽  
Clinical Source ◽  
Tract Infections

The reintroduction of colistin, a last-resort antibiotic for multidrug-resistant pathogens, resulted in the global spread of plasmid-mediated mobile colistin resistance (mcr) genes. Our study investigated the occurrence of colistin resistance among Escherichia coli isolated from patients with urinary tract infections admitted to a teaching hospital in Egypt. Out of 67 isolates, three isolates were colistin-resistant, having a minimum inhibitory concentration of 4 µg/mL and possessing the mcr-1 gene. A double mechanism of colistin resistance was detected; production of mcr-1 along with amino acid substitution in PmrB (E123D and Y358N) and PmrA (G144S). Broth mating experiments inferred that mcr-1 was positioned on conjugative plasmids. Whole-genome sequencing of EC13049 indicated that the isolate belonged to O23:H4-ST641 lineage and to phylogroup D. The mcr-1-bearing plasmid corresponded to IncHI2 type with a notable similarity to other E. coli plasmids previously recovered from Egypt. The unbanned use of colistin in the Egyptian agriculture sector might have created a potential reservoir for the mcr-1 gene in food-producing animals that spread to humans. More proactive regulations must be implemented to prevent further dissemination of this resistance. This is the first characterization of mcr-1-carrying IncHI2:ST4 plasmid recovered from E. coli of a clinical source in Egypt.

scholarly journals Peptidoglycan sensing prevents quiescence and promotes quorum-independent growth of uropathogenic Escherichia coli

2019 ◽  
Author(s):  
Eric C. DiBiasio ◽  
Hilary J. Ranson ◽  
James R. Johnson ◽  
David C. Rowley ◽  
Paul S. Cohen ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Structural Integrity ◽  
Recurrent Infection ◽  
Multidrug Resistant ◽  
Quiescent State ◽  
E Coli ◽  
Tract Infections ◽  
Patients Experience

AbstractThe layer of peptidoglycan surrounding bacteria provides structural integrity for the bacterial cell wall. Many organisms, including human cells and diverse bacteria, detect peptidoglycan fragments that are released as bacteria grow. Uropathogenic Escherichia coli (UPEC) strains are the leading cause of human urinary tract infections (UTIs) and many patients experience recurrent infection after successful antibiotic treatment. The source of recurrent infections may be persistent bacterial reservoirs in vivo that are in a quiescent state and, thus, are not susceptible to antibiotics. Here, we show that multiple UPEC strains require a quorum to proliferate in vitro with glucose as the sole carbon source; at low density, the bacteria remain viable but enter a quiescent, non-proliferative state. Of all clinical UPEC isolates tested to date, 35% (51/145) enter this quiescent state, including archetypal strains CFT073 (from classic endemic lineage ST73) and JJ1886 (from recently emerged, multidrug-resistant pandemic lineage ST131). We further show that quorum-dependent UPEC quiescence is prevented and reversed by small molecules, called proliferants, that stimulate growth, such as L-lysine, L-methionine, and peptidoglycan (PG) stem peptides, including an isolated PG pentapeptide from Staphylococcus aureus. Together, our results indicate that (i) uptake of L-lysine and (ii) PG peptide sensing by UPEC modulate the quorum-regulated decision to proliferate and further demonstrate that PG fragments are important for intra- and interspecies signaling in pathogenic E. coli.

scholarly journals Genome Sequence of Multidrug-Resistant Escherichia coli EC302/04, Isolated from a Human Tracheal Aspirate

2012 ◽  
Vol 194 (23) ◽  
pp. 6691-6692 ◽  
Author(s):  
Wing-Sze Ho ◽  
Han-Ming Gan ◽  
Kien-Pong Yap ◽  
Ganeswrie Balan ◽  
Chew Chieng Yeo ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Genome Sequence ◽  
Respiratory Tract Infections ◽  
Tracheal Aspirate ◽  
Multidrug Resistant ◽  
Etiologic Agent ◽  
Lower Respiratory Tract Infections ◽  
Content Type ◽  
E Coli ◽  
Tract Infections

ABSTRACTEscherichia coliis an important etiologic agent of lower respiratory tract infections (LRTI). Multidrug-resistantE. coliEC302/04 was isolated from a tracheal aspirate, and its genome sequence is expected to provide insights into antimicrobial resistance as well as adaptive and virulence mechanisms ofE. coliinvolved in LRTI.

scholarly journals Antibiotic Susceptibility and Molecular Characterization of Uropathogenic Escherichia coli Associated with Community-Acquired Urinary Tract Infections in Urban and Rural Settings in South Africa

2020 ◽  
Vol 5 (4) ◽  
pp. 176
Author(s):  
Purity Z. Kubone ◽  
Koleka P. Mlisana ◽  
Usha Govinden ◽  
Akebe Luther King Abia ◽  
Sabiha Y. Essack
Keyword(s):  
Escherichia Coli ◽  
South Africa ◽  
Urinary Tract ◽  
Urinary Tract Infections ◽  
Resistance Genes ◽  
Multidrug Resistant ◽  
Uropathogenic Escherichia Coli ◽  
Diffusion Method ◽  
E Coli ◽  
Tract Infections

We investigated the phenotypic and genotypic antibiotic resistance, and clonality of uropathogenic Escherichia coli (UPEC) implicated in community-acquired urinary tract infections (CA-UTIs) in KwaZulu-Natal, South Africa. Mid-stream urine samples (n = 143) were cultured on selective media. Isolates were identified using the API 20E kit and their susceptibility to 17 antibiotics tested using the disk diffusion method. Extended-spectrum β-lactamases (ESBLs) were detected using ROSCO kits. Polymerase chain reaction (PCR) was used to detect uropathogenic E. coli (targeting the papC gene), and β-lactam (blaTEM/blaSHV-like and blaCTX-M) and fluoroquinolone (qnrA, qnrB, qnrS, gyrA, parC, aac(6’)-Ib-cr, and qepA) resistance genes. Clonality was ascertained using ERIC-PCR. The prevalence of UTIs of Gram-negative etiology among adults 18–60 years of age in the uMgungundlovu District was 19.6%. Twenty-six E. coli isolates were obtained from 28 positive UTI samples. All E. coli isolates were papC-positive. The highest resistance was to ampicillin (76.9%) and the lowest (7.7%) to amoxicillin/clavulanic acid and gentamycin. Four isolates were multidrug-resistant and three were ESBL-positive, all being CTX-M-positive but SHV-negative. The aac(6’)-Ib-cr and gyrA were the most detected fluoroquinolone resistance genes (75%). Isolates were clonally distinct, suggesting the spread of genetically diverse UPEC clones within the three communities. This study highlights the spread of genetically diverse antibiotic-resistant CA-UTI aetiologic agents, including multidrug-resistant ones, and suggests a revision of current treatment options for CA-UTIs in rural and urban settings.

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