{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T05:18:18Z","timestamp":1790745498382,"version":"4.1.0"},"reference-count":41,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2020,5,27]],"date-time":"2020-05-27T00:00:00Z","timestamp":1590537600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["K12HD043494"],"award-info":[{"award-number":["K12HD043494"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["K08AI123524"],"award-info":[{"award-number":["K08AI123524"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100006510","name":"Duke University","doi-asserted-by":"publisher","award":["Duke Physician-Scientist Strong Start Award"],"award-info":[{"award-number":["Duke Physician-Scientist Strong Start Award"]}],"id":[{"id":"10.13039\/100006510","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>The recent rapid rise of multi-drug resistant Enterobacteriaceae (MDR-E) is threatening the treatment of common infectious diseases. Infections with such strains lead to increased mortality and morbidity. Using a cross-sectional study, we aimed to estimate the prevalence of gut colonization with extended spectrum beta-lactamase (ESBL) producing Enterobacteriaceae among healthy infants born in Pakistan, a setting with high incidence of MDR-E infections. Stool samples were collected from 104 healthy infants between the ages of 5 and 7 months. Enterobacteriaceae isolates were screened for resistance against several antimicrobial classes. Presence of ESBL and carbapenemase genes was determined using multiplex PCR. Sequence types were assigned to individual strains by multi-locus sequence typing. Phylogenetic analysis of Escherichia coli was done using the triplex PCR method. Forty-three percent of the infants were positive for ESBL-producing Enterobacteriaceae, the majority of which were E. coli. We identified several different ESBL E. coli sequence types most of which belonged to the phylogenetic group B2 (23%) or D (73%). The widespread colonization of infants in a developing country with ESBL-producing Enterobacteriaceae is concerning. The multiple sequence types and reported non-human sources support that multiple non-epidemic MDR lineages are circulating in Pakistan with healthy infants as a common reservoir.<\/jats:p>","DOI":"10.3390\/antibiotics9060286","type":"journal-article","created":{"date-parts":[[2020,5,28]],"date-time":"2020-05-28T08:27:48Z","timestamp":1590654468000},"page":"286","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["The Gut of Healthy Infants in the Community as a Reservoir of ESBL and Carbapenemase-Producing Bacteria"],"prefix":"10.3390","volume":"9","author":[{"given":"Ali F.","family":"Saleem","sequence":"first","affiliation":[{"name":"Department of Pediatrics and Child Health, Aga Khan University Hospital, National Stadium Rd, Karachi 74800, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7918-142X","authenticated-orcid":false,"given":"Ahreen","family":"Allana","sequence":"additional","affiliation":[{"name":"Department of Pediatrics and Child Health, Aga Khan University Hospital, National Stadium Rd, Karachi 74800, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lauren","family":"Hale","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Duke University, 2301 Erwin Rd, Durham, NC 27710, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5887-100X","authenticated-orcid":false,"given":"Alondra","family":"Diaz","sequence":"additional","affiliation":[{"name":"Ann &amp; Robert H. Lurie Children\u2019s Hospital, 225 E Chicago Ave, Chicago, IL 60611, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raul","family":"Salinas","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Duke University, 2301 Erwin Rd, Durham, NC 27710, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristina","family":"Salinas","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Duke University, 2301 Erwin Rd, Durham, NC 27710, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shahida M.","family":"Qureshi","sequence":"additional","affiliation":[{"name":"Department of Pediatrics and Child Health, Aga Khan University Hospital, National Stadium Rd, Karachi 74800, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aneeta","family":"Hotwani","sequence":"additional","affiliation":[{"name":"Department of Pediatrics and Child Health, Aga Khan University Hospital, National Stadium Rd, Karachi 74800, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Najeeb","family":"Rahman","sequence":"additional","affiliation":[{"name":"Department of Pediatrics and Child Health, Aga Khan University Hospital, National Stadium Rd, Karachi 74800, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Asia","family":"Khan","sequence":"additional","affiliation":[{"name":"Department of Pediatrics and Child Health, Aga Khan University Hospital, National Stadium Rd, Karachi 74800, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anita K.","family":"Zaidi","sequence":"additional","affiliation":[{"name":"Department of Pediatrics and Child Health, Aga Khan University Hospital, National Stadium Rd, Karachi 74800, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2870-2947","authenticated-orcid":false,"given":"Patrick C.","family":"Seed","sequence":"additional","affiliation":[{"name":"Ann &amp; Robert H. Lurie Children\u2019s Hospital, 225 E Chicago Ave, Chicago, IL 60611, USA"},{"name":"Stanley Manne Children\u2019s Research Institute, 303 E Superior St, Chicago, IL 60611, USA"},{"name":"Northwestern Feinberg School of Medicine, 420 E Superior St, Chicago, IL 60611, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mehreen","family":"Arshad","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Duke University, 2301 Erwin Rd, Durham, NC 27710, USA"},{"name":"Ann &amp; Robert H. Lurie Children\u2019s Hospital, 225 E Chicago Ave, Chicago, IL 60611, USA"},{"name":"Stanley Manne Children\u2019s Research Institute, 303 E Superior St, Chicago, IL 60611, USA"},{"name":"Northwestern Feinberg School of Medicine, 420 E Superior St, Chicago, IL 60611, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,27]]},"reference":[{"key":"ref_1","first-page":"154","article-title":"Aetiology of community-acquired neonatal sepsis in low and middle income countries","volume":"1","author":"Waters","year":"2011","journal-title":"J. Glob. Health"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"S10","DOI":"10.1097\/INF.0b013e3181958769","article-title":"Pathogens associated with sepsis in newborns and young infants in developing countries","volume":"28","author":"Zaidi","year":"2009","journal-title":"Pediatr. Infect. Dis. 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