{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,11]],"date-time":"2026-10-11T18:46:29Z","timestamp":1791744389814,"version":"4.3.4"},"reference-count":28,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2024,4,7]],"date-time":"2024-04-07T00:00:00Z","timestamp":1712448000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Indian Council of Medical Research (ICMR) New Delhi","award":["8\/1\/14\/2019\/Nano\/BMS"],"award-info":[{"award-number":["8\/1\/14\/2019\/Nano\/BMS"]}]},{"name":"Indian Council of Medical Research (ICMR) New Delhi","award":["R01 AI132674"],"award-info":[{"award-number":["R01 AI132674"]}]},{"DOI":"10.13039\/100000002","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["8\/1\/14\/2019\/Nano\/BMS"],"award-info":[{"award-number":["8\/1\/14\/2019\/Nano\/BMS"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["R01 AI132674"],"award-info":[{"award-number":["R01 AI132674"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Scrub typhus is a re-emerging disease caused by Orientia tsutsugamushi, transmitted by mites belonging to the family Trombiculidae. Humans and rodents acquire the infection by the bite of larval mites\/chiggers. Suncus murinus, the Asian house shrew, has been reported to harbor the vector mites and has been naturally infected with O. tsutsugamushi. The present study aimed to localize and record O. tsutsugamushi in the tissues and the host response in shrews naturally infected with O. tsutsugamushi. Sheehan\u2019s modified May\u2013Grunwald Giemsa staining was carried out in 365 tissues from 87 animals, and rickettsiae were documented in 87 tissues from 20 animals. Immunohistochemical (IHC) staining, using polyclonal antibodies raised against selected epitopes of the 56-kDa antigen, was carried out, and 81\/87 tissue sections were tested positive for O. tsutsugamushi. By IHC, in addition to the endothelium, the pathogen was also demonstrated by IHC in cardiomyocytes, the bronchiolar epithelium, stroma of the lungs, hepatocytes, the bile duct epithelium, the epithelium and goblet cells of intestine, the tubular epithelium of the kidney, and splenic macrophages. Furthermore, the pathogen was confirmed by real-time PCR using blood (n = 20) and tissues (n = 81) of the IHC-positive animals. None of the blood samples and only 22 out of 81 IHC-positive tissues were tested positive by PCR. By nucleotide sequencing of the 56-kDa gene, Gilliam and Karp strains were found circulating among these animals. Although these bacterial strains are highly virulent and cause a wide range of pathological alterations, hence exploring their adaptive mechanisms of survival in shrews will be of significance. Given that the pathogen localizes in various organs following a transient bacteremia, we recommend the inclusion of tissues from the heart, lung, intestine, and kidney of reservoir animals, in addition to blood samples, for future molecular surveillance of scrub typhus.<\/jats:p>","DOI":"10.3390\/microorganisms12040748","type":"journal-article","created":{"date-parts":[[2024,4,8]],"date-time":"2024-04-08T12:01:22Z","timestamp":1712577682000},"page":"748","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Pathological Responses in Asian House Shrews (Suncus murinus) to the Naturally Acquired Orientia tsutsugamushi Infection"],"prefix":"10.3390","volume":"12","author":[{"given":"Tharani","family":"Balasubramanian","sequence":"first","affiliation":[{"name":"Department of Veterinary Pathology, Rajiv Gandhi Institute of Veterinary Education and Research, Kurumbapet, Puducherry 605009, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Uma","family":"Sambath","sequence":"additional","affiliation":[{"name":"Department of Veterinary Pathology, Rajiv Gandhi Institute of Veterinary Education and Research, Kurumbapet, Puducherry 605009, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ranjana Devi","family":"Radja","sequence":"additional","affiliation":[{"name":"Unit of One Health, ICMR\u2014Vector Control Research Centre, Indira Nagar, Puducherry 605006, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gowdham","family":"Thangaraj","sequence":"additional","affiliation":[{"name":"Unit of One Health, ICMR\u2014Vector Control Research Centre, Indira Nagar, Puducherry 605006, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0638-9590","authenticated-orcid":false,"given":"Panneer","family":"Devaraju","sequence":"additional","affiliation":[{"name":"Unit of One Health, ICMR\u2014Vector Control Research Centre, Indira Nagar, Puducherry 605006, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lakshmy","family":"Srinivasan","sequence":"additional","affiliation":[{"name":"Unit of One Health, ICMR\u2014Vector Control Research Centre, Indira Nagar, Puducherry 605006, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pushpa","family":"Srinivasan","sequence":"additional","affiliation":[{"name":"Unit of One Health, ICMR\u2014Vector Control Research Centre, Indira Nagar, Puducherry 605006, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Madhavan Gopalakrishnan","family":"Nair","sequence":"additional","affiliation":[{"name":"Department of Veterinary Pathology, Rajiv Gandhi Institute of Veterinary Education and Research, Kurumbapet, Puducherry 605009, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kumar","family":"Raja","sequence":"additional","affiliation":[{"name":"Department of Veterinary Pathology, Rajiv Gandhi Institute of Veterinary Education and Research, Kurumbapet, Puducherry 605009, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Avinash Warundeo","family":"Lakkawar","sequence":"additional","affiliation":[{"name":"Department of Veterinary Pathology, Rajiv Gandhi Institute of Veterinary Education and Research, Kurumbapet, Puducherry 605009, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3370-3434","authenticated-orcid":false,"given":"Lynn","family":"Soong","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, Institute for Human Infections & Immunity, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Xu, G., Walker, D.H., Jupiter, D., Melby, P.C., and Arcari, C.M. 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