{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T17:02:25Z","timestamp":1783702945239,"version":"3.55.0"},"reference-count":26,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,8,15]],"date-time":"2025-08-15T00:00:00Z","timestamp":1755216000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Hainan Provincial International Science and Technology Cooperation Research and Development Project","award":["GHYF2024021"],"award-info":[{"award-number":["GHYF2024021"]}]},{"name":"Hainan Provincial International Science and Technology Cooperation Research and Development Project","award":["82060378"],"award-info":[{"award-number":["82060378"]}]},{"name":"Hainan Provincial International Science and Technology Cooperation Research and Development Project","award":["825RC880"],"award-info":[{"award-number":["825RC880"]}]},{"name":"Hainan Provincial International Science and Technology Cooperation Research and Development Project","award":["824MS067"],"award-info":[{"award-number":["824MS067"]}]},{"name":"Hainan Provincial International Science and Technology Cooperation Research and Development Project","award":["G20230324004Y"],"award-info":[{"award-number":["G20230324004Y"]}]},{"name":"Hainan Provincial International Science and Technology Cooperation Research and Development Project","award":["GZNL2023A01001"],"award-info":[{"award-number":["GZNL2023A01001"]}]},{"name":"the National Natural Science Foundation of China","award":["GHYF2024021"],"award-info":[{"award-number":["GHYF2024021"]}]},{"name":"the National Natural Science Foundation of China","award":["82060378"],"award-info":[{"award-number":["82060378"]}]},{"name":"the National Natural Science Foundation of China","award":["825RC880"],"award-info":[{"award-number":["825RC880"]}]},{"name":"the National Natural Science Foundation of China","award":["824MS067"],"award-info":[{"award-number":["824MS067"]}]},{"name":"the National Natural Science Foundation of China","award":["G20230324004Y"],"award-info":[{"award-number":["G20230324004Y"]}]},{"name":"the National Natural Science Foundation of China","award":["GZNL2023A01001"],"award-info":[{"award-number":["GZNL2023A01001"]}]},{"name":"Hainan Provincial Natural Science Foundation of China","award":["GHYF2024021"],"award-info":[{"award-number":["GHYF2024021"]}]},{"name":"Hainan Provincial Natural Science Foundation of China","award":["82060378"],"award-info":[{"award-number":["82060378"]}]},{"name":"Hainan Provincial Natural Science Foundation of China","award":["825RC880"],"award-info":[{"award-number":["825RC880"]}]},{"name":"Hainan Provincial Natural Science Foundation of China","award":["824MS067"],"award-info":[{"award-number":["824MS067"]}]},{"name":"Hainan Provincial Natural Science Foundation of China","award":["G20230324004Y"],"award-info":[{"award-number":["G20230324004Y"]}]},{"name":"Hainan Provincial Natural Science Foundation of China","award":["GZNL2023A01001"],"award-info":[{"award-number":["GZNL2023A01001"]}]},{"name":"Major Project of Guangzhou National Laboratory","award":["GHYF2024021"],"award-info":[{"award-number":["GHYF2024021"]}]},{"name":"Major Project of Guangzhou National Laboratory","award":["82060378"],"award-info":[{"award-number":["82060378"]}]},{"name":"Major Project of Guangzhou National Laboratory","award":["825RC880"],"award-info":[{"award-number":["825RC880"]}]},{"name":"Major Project of Guangzhou National Laboratory","award":["824MS067"],"award-info":[{"award-number":["824MS067"]}]},{"name":"Major Project of Guangzhou National Laboratory","award":["G20230324004Y"],"award-info":[{"award-number":["G20230324004Y"]}]},{"name":"Major Project of Guangzhou National Laboratory","award":["GZNL2023A01001"],"award-info":[{"award-number":["GZNL2023A01001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Co-infection of Orientia tsutsugamushi and influenza A virus complicates diagnosis and treatment in endemic regions because of overlapping clinical features and potential synergistic inflammation. We describe a 68-year-old woman from Hainan, China, who presented with five days of high fever (39.2 \u00b0C), nonproductive cough, eschar formation, lymphadenopathy, cytopenias, elevated liver enzymes, and raised inflammatory markers. On the day of admission, influenza A was confirmed by rapid antigen test and Orientia tsutsugamushi IgM\/IgG was detected via colloidal-gold immunochromatography, prompting concurrent oseltamivir and doxycycline therapy. Quantitative PCR on day 2 measured an Orientia tsutsugamushi load of 2.85 \u00d7 104 copies\/mL (Cq 28.86), and targeted next-generation sequencing on day 3 revealed a high H1N1pdm09 viral burden (&gt;1 \u00d7 106 copies\/mL) with low-level human herpesvirus 1 co-detection. Nested PCR and Sanger sequencing assigned Orientia tsutsugamushi to the Karp_A lineage and influenza A to clade 6B.1A.5a.2a. The patient defervesced by hospital day 2, laboratory indices normalized by day 3, and radiographic abnormalities resolved by day 6. This first documented Orientia tsutsugamushi\u2013influenza A co-infection in China highlights the value of integrating rapid serology, qPCR quantification, nested PCR genotyping, and tNGS for early, precise dual-pathogen identification. Systematic multi-pathogen screening during overlapping transmission seasons is recommended to guide timely combination therapy and enhance epidemiological surveillance.<\/jats:p>","DOI":"10.3390\/pathogens14080810","type":"journal-article","created":{"date-parts":[[2025,8,15]],"date-time":"2025-08-15T10:33:42Z","timestamp":1755254022000},"page":"810","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Comprehensive Laboratory Analysis of a Scrub Typhus and H1N1 Influenza Co-Infection: A Case Report from Hainan, China"],"prefix":"10.3390","volume":"14","author":[{"given":"Siqi","family":"Chen","sequence":"first","affiliation":[{"name":"The University of Hong Kong Joint Laboratory of Tropical Infectious Diseases\u2014Hainan Medical University, Key Laboratory of Tropical Translational Medicine of Ministry of Education, Academician Workstation of Hainan Province, School of Basic Medicine and Life Sciences, Hainan Medical University, Haikou 571199, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fahui","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine, The Second Affiliated Hospital, Hainan Medical University, Haikou 570311, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shannan","family":"Wu","sequence":"additional","affiliation":[{"name":"Animal and Plant Quarantine Center, Haikou Customs District, Haikou 570311, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuanze","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, The Second Affiliated Hospital, Hainan Medical University, Haikou 570311, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi","family":"Niu","sequence":"additional","affiliation":[{"name":"The University of Hong Kong Joint Laboratory of Tropical Infectious Diseases\u2014Hainan Medical University, Key Laboratory of Tropical Translational Medicine of Ministry of Education, Academician Workstation of Hainan Province, School of Basic Medicine and Life Sciences, Hainan Medical University, Haikou 571199, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yijia","family":"Guo","sequence":"additional","affiliation":[{"name":"The University of Hong Kong Joint Laboratory of Tropical Infectious Diseases\u2014Hainan Medical University, Key Laboratory of Tropical Translational Medicine of Ministry of Education, Academician Workstation of Hainan Province, School of Basic Medicine and Life Sciences, Hainan Medical University, Haikou 571199, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dachuan","family":"Lin","sequence":"additional","affiliation":[{"name":"The University of Hong Kong Joint Laboratory of Tropical Infectious Diseases\u2014Hainan Medical University, Key Laboratory of Tropical Translational Medicine of Ministry of Education, Academician Workstation of Hainan Province, School of Basic Medicine and Life Sciences, Hainan Medical University, Haikou 571199, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1707-2492","authenticated-orcid":false,"given":"Xiuji","family":"Cui","sequence":"additional","affiliation":[{"name":"The University of Hong Kong Joint Laboratory of Tropical Infectious Diseases\u2014Hainan Medical University, Key Laboratory of Tropical Translational Medicine of Ministry of Education, Academician Workstation of Hainan Province, School of Basic Medicine and Life Sciences, Hainan Medical University, Haikou 571199, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruoyan","family":"Peng","sequence":"additional","affiliation":[{"name":"The University of Hong Kong Joint Laboratory of Tropical Infectious Diseases\u2014Hainan Medical University, Key Laboratory of Tropical Translational Medicine of Ministry of Education, Academician Workstation of Hainan Province, School of Basic Medicine and Life Sciences, Hainan Medical University, Haikou 571199, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhao","family":"Xu","sequence":"additional","affiliation":[{"name":"The University of Hong Kong Joint Laboratory of Tropical Infectious Diseases\u2014Hainan Medical University, Key Laboratory of Tropical Translational Medicine of Ministry of Education, Academician Workstation of Hainan Province, School of Basic Medicine and Life Sciences, Hainan Medical University, Haikou 571199, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Biao","family":"Wu","sequence":"additional","affiliation":[{"name":"Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou 570100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Min","family":"Liao","sequence":"additional","affiliation":[{"name":"Hainan General Hospital, 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