{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T18:40:14Z","timestamp":1788374414737,"version":"build-2803163510"},"reference-count":39,"publisher":"American Society of Tropical Medicine and Hygiene","issue":"2","license":[{"start":{"date-parts":[[2024,8,7]],"date-time":"2024-08-07T00:00:00Z","timestamp":1722988800000},"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":[[2024,8,7]]},"abstract":"<jats:title>ABSTRACT.<\/jats:title>\n                  <jats:p>\n                    Scrub typhus, a vector-borne bacterial infection, is an important but neglected disease globally. Accurately characterizing the burden is challenging because of nonspecific symptoms and limited diagnostics. Prior seroepidemiology studies have struggled to find consensus cutoffs that permit comparisons of estimates across contexts and time. In this study, we present a novel approach that does not require a cutoff and instead uses information about antibody kinetics after infection to estimate seroincidence. We use data from three cohorts of scrub typhus patients in Chiang Rai, Thailand, and Vellore, India, to characterize antibody kinetics after infection and two population serosurveys in the Kathmandu Valley, Nepal, and Tamil Nadu, India, to estimate seroincidence. The samples were tested for IgM and IgG responses to\n                    <jats:italic>Orientia tsutsugamushi<\/jats:italic>\n                    -derived recombinant 56-kDa antigen using commercial enzyme-linked immunosorbent assay kits. We used Bayesian hierarchical models to characterize antibody responses after scrub typhus infection and used the joint distributions of the peak antibody titers and decay rates to estimate population-level incidence rates in the cross-sectional serosurveys. Median responses persisted above an optical density (OD) of 1.8 for 23.6 months for IgG and an OD of 1 for 4.5 months for IgM. Among 18- to 29-year-olds, the seroincidence was 10 per 1,000 person-years (95% CI, 5\u201319) in Tamil Nadu, India, and 14 per 1,000 person-years (95% CI: 10\u201320) in the Kathmandu Valley, Nepal. When seroincidence was calculated with antibody decay ignored, the disease burden was underestimated by more than 50%. The approach can be deployed prospectively, coupled with existing serosurveys, or leverage banked samples to efficiently generate scrub typhus seroincidence estimates.\n                  <\/jats:p>","DOI":"10.4269\/ajtmh.23-0475","type":"journal-article","created":{"date-parts":[[2024,6,11]],"date-time":"2024-06-11T13:43:14Z","timestamp":1718113394000},"page":"267-276","source":"Crossref","is-referenced-by-count":8,"title":["Estimating the Seroincidence of Scrub Typhus using Antibody Dynamics after Infection"],"prefix":"10.4269","volume":"111","author":[{"given":"Kristen","family":"Aiemjoy","sequence":"first","affiliation":[{"name":"Department of Public Health Sciences, University of California Davis School of Medicine, Davis, California;"},{"name":"Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nishan","family":"Katuwal","sequence":"additional","affiliation":[{"name":"Dhulikhel Hospital, Kathmandu University Hospital, Dhulikhel, Nepal;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Krista","family":"Vaidya","sequence":"additional","affiliation":[{"name":"Department of Public Health Sciences, University of California Davis School of Medicine, Davis, California;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sony","family":"Shrestha","sequence":"additional","affiliation":[{"name":"Dhulikhel Hospital, Kathmandu University Hospital, Dhulikhel, Nepal;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Melina","family":"Thapa","sequence":"additional","affiliation":[{"name":"Dhulikhel Hospital, Kathmandu University Hospital, Dhulikhel, Nepal;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter","family":"Teunis","sequence":"additional","affiliation":[{"name":"Center for Global Safe Water, Sanitation and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Isaac I.","family":"Bogoch","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Toronto, Toronto, Ontario, Canada;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul","family":"Trowbridge","sequence":"additional","affiliation":[{"name":"Michigan State University College of Human Medicine, Grand Rapids, Michigan;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stuart D.","family":"Blacksell","sequence":"additional","affiliation":[{"name":"Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand;"},{"name":"Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel H.","family":"Paris","sequence":"additional","affiliation":[{"name":"Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand;"},{"name":"Department of Medicine, Swiss Tropical and Public Health Institute, Basel, Switzerland;"},{"name":"Department of Clinical Research, University of Basel, Switzerland;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tri","family":"Wangrangsimakul","sequence":"additional","affiliation":[{"name":"Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"George M.","family":"Varghese","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, Christian Medical College, Vellore, India;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard J.","family":"Maude","sequence":"additional","affiliation":[{"name":"Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand;"},{"name":"Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom;"},{"name":"The Open University, Milton Keynes, United Kingdom;"},{"name":"School of Public Health, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dipesh","family":"Tamrakar","sequence":"additional","affiliation":[{"name":"Dhulikhel Hospital, Kathmandu University Hospital, Dhulikhel, Nepal;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jason R.","family":"Andrews","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"2795","reference":[{"key":"b1","series-title":"Am J Trop Med Hyg","first-page":"301","article-title":"Unresolved problems related to scrub typhus: A seriously neglected life-threatening disease","volume":"89","author":"Paris","year":"2013"},{"key":"b2","series-title":"N Engl J Med","first-page":"954","article-title":"Endemic scrub typhus in South America","volume":"375","author":"Weitzel","year":"2016"},{"key":"b3","series-title":"J Clin Microbiol","first-page":"4404","article-title":"Isolation of a novel Orientia species (O. chuto sp. nov.) from a patient infected in Dubai","volume":"48","author":"Izzard","year":"2010"},{"key":"b4","series-title":"Emerg Infect Dis","first-page":"688","article-title":"High seroprevalence of antibodies against spotted fever and scrub typhus bacteria in patients with febrile illness, 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