{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,24]],"date-time":"2025-10-24T08:26:54Z","timestamp":1761294414704,"version":"build-2065373602"},"reference-count":34,"publisher":"American Society of Tropical Medicine and Hygiene","issue":"3","license":[{"start":{"date-parts":[[2022,3,9]],"date-time":"2022-03-09T00:00:00Z","timestamp":1646784000000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,3,9]]},"abstract":"<jats:title>ABSTRACT.<\/jats:title>\n<jats:p>Approximately 90% of chronic typhoid carriers with persistent <jats:italic>Salmonella enterica<\/jats:italic> serovar Typhi (<jats:italic>S.<\/jats:italic> Typhi) gallbladder infection have gallstones. In Samoa, where typhoid fever has been endemic for many decades, risk factors predisposing to the development of gallstones are increasing among adults. The Samoa Typhoid Fever Control Program dispatches a \u201cTyphoid Epidemiologic SWAT Team\u201d to perform a household investigation of every blood culture-confirmed case of acute typhoid fever. Investigations include screening household contacts to detect chronic carriers. Following limited training, two nonexpert ultrasound operators performed point-of-care ultrasound (POCUS) on 120 Samoan adults from August to September 2019 to explore the feasibility of POCUS to detect individuals with gallstones during household investigations and community screenings. POCUS scans from 120 Samoan adults in three cohorts (28 food handlers, two typhoid cases and their 18 household contacts, and 72 attendees at an ambulatory clinic) were reviewed by a board-certified radiologist who deemed 96\/120 scans (80%) to be interpretable. Compared with the radiologist (gold standard), the nonexpert operators successfully detected 6\/7 Samoans with gallstones (85.7% sensitivity) and correctly identified 85\/89 without gallstones (95.5% specificity). The proportion (24\/120) of uninterpretable scans from this pilot that used minimally trained clinicians (who are neither radiologists nor ultrasound technicians) indicates the need for additional training of POCUS operators. Nevertheless, this pilot feasibility study engenders optimism that in the Samoan setting nonexperts can be trained to use POCUS to diagnose cholelithiasis, thereby helping (along with stool cultures and Vi serology) to identify possible chronic <jats:italic>S.<\/jats:italic> Typhi carriers.<\/jats:p>","DOI":"10.4269\/ajtmh.21-0973","type":"journal-article","created":{"date-parts":[[2022,1,10]],"date-time":"2022-01-10T07:43:34Z","timestamp":1641800614000},"page":"798-804","source":"Crossref","is-referenced-by-count":2,"title":["Point-of-Care Ultrasound by Nonexpert Operators Demonstrates High Sensitivity and Specificity in Detecting Gallstones: Data from the Samoa Typhoid Fever Control Program"],"prefix":"10.4269","volume":"106","author":[{"given":"Seth A.","family":"Hoffman","sequence":"first","affiliation":[{"name":"Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland;"},{"name":"Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sachin N.","family":"Desai","sequence":"additional","affiliation":[{"name":"Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland;"},{"name":"Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland;"},{"name":"Samoa Typhoid Fever Control Program, Ministry of Health, Government of Samoa, Apia, Samoa;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael J.","family":"Sikorski","sequence":"additional","affiliation":[{"name":"Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland;"},{"name":"Samoa Typhoid Fever Control Program, Ministry of Health, Government of Samoa, Apia, Samoa;"},{"name":"Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, Maryland;"},{"name":"Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Glenn","family":"Fatupaito","sequence":"additional","affiliation":[{"name":"Tupua Tamasese Meaole Hospital, Ministry of Health, Government of Samoa, Apia, Samoa;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Siaosi","family":"Tupua","sequence":"additional","affiliation":[{"name":"Samoa Typhoid Fever Control Program, Ministry of Health, Government of Samoa, Apia, Samoa;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Robert E.","family":"Thomsen","sequence":"additional","affiliation":[{"name":"Samoa Typhoid Fever Control Program, Ministry of Health, Government of Samoa, Apia, Samoa;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Savitra","family":"Rambocus","sequence":"additional","affiliation":[{"name":"Samoa Typhoid Fever Control Program, Ministry of Health, Government of Samoa, Apia, Samoa;"},{"name":"Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Susana","family":"Nimarota-Brown","sequence":"additional","affiliation":[{"name":"Samoa Typhoid Fever Control Program, Ministry of Health, Government of Samoa, Apia, Samoa;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Linatupu L.","family":"Punimata","sequence":"additional","affiliation":[{"name":"Samoa Typhoid Fever Control Program, Ministry of Health, Government of Samoa, Apia, Samoa;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michelle","family":"Sialeipata","sequence":"additional","affiliation":[{"name":"Samoa Typhoid Fever Control Program, Ministry of Health, Government of Samoa, Apia, Samoa;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chandler F.","family":"Tuilagi","sequence":"additional","affiliation":[{"name":"Tupua Tamasese Meaole Hospital, Ministry of Health, Government of Samoa, Apia, Samoa;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jane","family":"Han","sequence":"additional","affiliation":[{"name":"Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland;"},{"name":"Samoa Typhoid Fever Control Program, Ministry of Health, Government of Samoa, Apia, Samoa;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Roy M.","family":"Robins-Browne","sequence":"additional","affiliation":[{"name":"Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia;"},{"name":"Murdoch Children\u2019s Research Institute, Royal Children\u2019s Hospital, Melbourne, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Take K.","family":"Naseri","sequence":"additional","affiliation":[{"name":"Samoa Typhoid Fever Control Program, Ministry of Health, Government of Samoa, Apia, Samoa;"},{"name":"Tupua Tamasese Meaole Hospital, Ministry of Health, Government of Samoa, Apia, Samoa;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Myron M.","family":"Levine","sequence":"additional","affiliation":[{"name":"Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland;"},{"name":"Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland;"},{"name":"Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland;"},{"name":"Samoa Typhoid Fever Control Program, Ministry of Health, Government of Samoa, Apia, Samoa;"},{"name":"Department of Microbiology and Immunology, 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