{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T20:16:39Z","timestamp":1789416999491,"version":"build-2803163510"},"reference-count":44,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2022,5,31]],"date-time":"2022-05-31T00:00:00Z","timestamp":1653955200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Defense Threat Reduction Agency\u2019s Biothreat Reduction Program","award":["A1266"],"award-info":[{"award-number":["A1266"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["TropicalMed"],"abstract":"<jats:p>In Vietnam, the public health burden of rickettsial infections continues to be underestimated due to knowledge gaps in the epidemiology of these diseases. We conducted a systematic study among 27 hospitals from 26 provinces in eight ecological regions throughout Vietnam to investigate the prevalence, distribution, and clinical characteristics of rickettsial diseases. We recruited 1834 patients in the study from April 2018 to October 2019. The findings showed that rickettsial diseases were common among undifferentiated febrile patients, with 564 (30.8%) patients positive by qPCR for scrub typhus, murine typhus or spotted fever. Scrub typhus (484, 85.8%) was the most common rickettsial disease, followed by murine typhus (67, 11.9%) and spotted fever (10, 1.8%). Rickettsial diseases were widely distributed in all regions of Vietnam and presented with nonspecific clinical manifestations.<\/jats:p>","DOI":"10.3390\/tropicalmed7060088","type":"journal-article","created":{"date-parts":[[2022,5,31]],"date-time":"2022-05-31T10:54:23Z","timestamp":1653994463000},"page":"88","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Systematic Surveillance of Rickettsial Diseases in 27 Hospitals from 26 Provinces throughout Vietnam"],"prefix":"10.3390","volume":"7","author":[{"given":"Nguyen Vu","family":"Trung","sequence":"first","affiliation":[{"name":"Hanoi Medical University, Hanoi 100000, Vietnam"},{"name":"Pasteur Institute in Ho Chi Minh City, Ho Chi Minh City 700000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Le Thi","family":"Hoi","sequence":"additional","affiliation":[{"name":"Hanoi Medical University, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tran Mai","family":"Hoa","sequence":"additional","affiliation":[{"name":"Hanoi Medical University, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dang Thi","family":"Huong","sequence":"additional","affiliation":[{"name":"Hanoi Medical University, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ma Thi","family":"Huyen","sequence":"additional","affiliation":[{"name":"Hanoi Medical University, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vuong Quang","family":"Tien","sequence":"additional","affiliation":[{"name":"Hanoi Medical University, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dao Thi Tuyet","family":"Mai","sequence":"additional","affiliation":[{"name":"Hanoi Medical University, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nguyen Thi Thu","family":"Ha","sequence":"additional","affiliation":[{"name":"Hanoi University of Public Health, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nguyen Van","family":"Kinh","sequence":"additional","affiliation":[{"name":"National Hospital for Tropical Diseases, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christina M.","family":"Farris","sequence":"additional","affiliation":[{"name":"Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD 20910, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1065-429X","authenticated-orcid":false,"given":"Allen L.","family":"Richards","sequence":"additional","affiliation":[{"name":"Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD 20910, USA"},{"name":"Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1493","DOI":"10.1086\/425365","article-title":"Rickettsioses and the International Traveler","volume":"39","author":"Ericsson","year":"2004","journal-title":"Clin. 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