{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T20:50:10Z","timestamp":1792788610399,"version":"4.5.0"},"reference-count":27,"publisher":"Public Library of Science (PLoS)","issue":"2","license":[{"start":{"date-parts":[[2024,2,23]],"date-time":"2024-02-23T00:00:00Z","timestamp":1708646400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NIH\/NIAID","award":["Grant Ref R01 AI099525-06A1"],"award-info":[{"award-number":["Grant Ref R01 AI099525-06A1"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"\n Introduction<\/jats:title>\n \n Multiple studies have shown that typhoid fever is endemic in developing countries characterized by poor hygiene. A unique way of\n Salmonella<\/jats:italic>\n Typhi (\n S<\/jats:italic>\n .Typhi) pathogenicity is establishing a persistent, usually asymptomatic carrier state in some infected individuals who excrete large numbers of bacteria in faeces. This study aimed to determine the isolation rate of\n S<\/jats:italic>\n .Typhi from blood and stool samples among cases and asymptomatic individuals in the Mukuru informal settlement and identify antibiotic resistance patterns within the same population.\n <\/jats:p>\n <\/jats:sec>\n \n Materials and methods<\/jats:title>\n \n We recruited 1014 outpatient participants presenting with typhoid-like symptoms in selected health centres in Nairobi, Kenya. Bacterial isolation was done on Xylose Lysine Deoxycholate agar (XLD) and Mac Conkey agar (Oxoid), followed by standard biochemical tests. Identification was done using API20E, and\n S<\/jats:italic>\n .Typhi was confirmed by serotyping using polyvalent antisera 0\u20139 and monovalent antisera d. The Kirby-Bauer disc diffusion method was used to test the antimicrobial susceptibility of\n S<\/jats:italic>\n .Typhi isolates, while Multi-Drug Resistant (MDR) strains were characterized using conventional PCR.\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n Of 1014 participants, 54 (5%) tested positive for\n S<\/jats:italic>\n .Typhi. Thirty-eight (70%) of the\n S<\/jats:italic>\n .Typhi isolated were from stool samples, while sixteen (30%) were from blood. Three (0.2%) of the isolates were from asymptomatic carriers. Of the 54\n S<\/jats:italic>\n .Typhi isolates, 20 (37%) were MDR. Resistance to ciprofloxacin and nalidixic acid was 43% and 52%, respectively. Resistance to amoxicillin-clavulanic acid (a beta-lactam inhibitor) was 2%. The\n Bla<\/jats:italic>\n TEM-1<\/jats:sub>\n gene was present in 19\/20 (95%) MDR isolates.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n \n MDR\n S<\/jats:italic>\n .Typhi is prevalent in Mukuru Informal settlement. The sharp increase in nalidixic acid resistance is an indication of reduced susceptibility to fluoroquinolones, which are currently the recommended drugs for the treatment of typhoid fever. This study highlights the need for effective antimicrobial stewardship and routine surveillance of antimicrobial resistance (AMR) to inform policy on the prevention and control of MDR Typhoid disease.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.1371\/journal.pone.0298635","type":"journal-article","created":{"date-parts":[[2024,2,23]],"date-time":"2024-02-23T13:45:27Z","timestamp":1708695927000},"page":"e0298635","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":5,"title":["Typhoidal salmonella disease in Mukuru informal settlement, Nairobi Kenya; carriage, diversity, and antimicrobial resistant genes"],"prefix":"10.1371","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2065-0732","authenticated-orcid":true,"given":"Purity","family":"Kasiano","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Susan","family":"Kavai","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Susan","family":"Kiiru","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew","family":"Nyerere","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samuel","family":"Kariuki","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2024,2,23]]},"reference":[{"key":"pone.0298635.ref001","first-page":"NP2740\u20138","article-title":"Identification of carriers among individuals recruited in the typhoid registry in Malaysia using stool culture, polymerase chain reaction, and dot enzyme immunoassay as detection tools","volume":"27","author":"AL Chua","year":"2015","journal-title":"Asia Pac J Public Health"},{"key":"pone.0298635.ref002","doi-asserted-by":"crossref","first-page":"4353","DOI":"10.1073\/pnas.1000862107","article-title":"Gallstones play a significant role in Salmonella spp. gallbladder colonization and carriage","volume":"107","author":"RW Crawford","year":"2010","journal-title":"Proc Natl Acad Sci U S A"},{"key":"pone.0298635.ref003","doi-asserted-by":"crossref","first-page":"317","DOI":"10.1146\/annurev-micro-091313-103739","article-title":"Salmonella enterica Serovar Typhi and the Pathogenesis of Typhoid Fever","volume":"68","author":"G Dougan","year":"2014","journal-title":"Annu Rev Microbiol"},{"key":"pone.0298635.ref004","first-page":"1","article-title":"A systematic review of antimicrobial resistance in Salmonella enterica serovar Typhi, the etiological agent of typhoid","author":"CDB Id","year":"2018"},{"key":"pone.0298635.ref005","doi-asserted-by":"crossref","first-page":"443","DOI":"10.3855\/jidc.159","article-title":"Typhoid fever in sub-Saharan Africa: challenges of diagnosis and management of infections","volume":"2","author":"S. 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