{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:00:32Z","timestamp":1787029232047,"version":"build-2736575974"},"reference-count":42,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,4,1]],"date-time":"2021-04-01T00:00:00Z","timestamp":1617235200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>The currently known animal reservoir for MERS-CoV is the dromedary camel. The clinical pattern of the MERS-CoV field infection in dromedary camels is not yet fully studied well. Some pathological changes and the detection of the MERS-CoV antigens by immunohistochemistry have been recently reported. However, the nature of these changes by the scanning electron microscope (SEM) was not revealed. The objective of this study was to document some changes in the respiratory organs induced by the natural MERS-CoV infection using the SEM. We previously identified three positive animals naturally infected with MERS-CoV and two other negative animals. Previous pathological studies on the positive animals showed varying degrees of alterations. MERS-CoV-S and MERS-CoV-Nc proteins were detected in the organs of positive animals. In the current study, we used the same tissues and sections for the SEM examination. We established a histopathology lesion scoring system by the SEM for the nasal turbinate and trachea. Our results showed various degrees of involvement per animal. The main observed characteristic findings are massive ciliary loss, ciliary disorientation, and goblet cell hyperplasia, especially in the respiratory organs, particularly the nasal turbinate and trachea in some animals. The lungs of some affected animals showed signs of marked interstitial pneumonia with damage to the alveolar walls. The partial MERS-CoV-S gene sequencing from the nasal swabs of some dromedary camels admitted to this slaughterhouse confirms the circulating strains belong to clade-B of MERS-CoV. These results confirm the respiratory tropism of the virus and the detection of the virus in the nasal cavity. Further studies are needed to explore the pathological alterations induced by MERS-CoV infection in various body organs of the MERS-CoV naturally infected dromedary camels.<\/jats:p>","DOI":"10.3390\/pathogens10040420","type":"journal-article","created":{"date-parts":[[2021,4,1]],"date-time":"2021-04-01T10:44:01Z","timestamp":1617273841000},"page":"420","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Scanning Electron Microscopic Findings on Respiratory Organs of Some Naturally Infected Dromedary Camels with the Lineage-B of the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) in Saudi Arabia\u20142018"],"prefix":"10.3390","volume":"10","author":[{"given":"Abdelmohsen","family":"Alnaeem","sequence":"first","affiliation":[{"name":"Department of Clinical Studies, College of Veterinary Medicine, King Faisal University, Al-Haa 400, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8730-7333","authenticated-orcid":false,"given":"Samy","family":"Kasem","sequence":"additional","affiliation":[{"name":"Veterinary Health and Monitoring, Ministry of Environment, Water and Agriculture, Riyadh 11195, Saudi Arabia"},{"name":"Department of Virology, Faculty of Veterinary Medicine, Kafrelsheikh University, Kafrelsheikh 33516, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ibrahim","family":"Qasim","sequence":"additional","affiliation":[{"name":"Veterinary Health and Monitoring, Ministry of Environment, Water and Agriculture, Riyadh 11195, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9068-2444","authenticated-orcid":false,"given":"Mohamed","family":"Refaat","sequence":"additional","affiliation":[{"name":"Veterinary Health and Monitoring, Ministry of Environment, Water and Agriculture, Riyadh 11195, Saudi Arabia"},{"name":"Department of Pathology, Animal Health Research Institute, Dokki, Cairo 12618, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ali Nasser","family":"Alhufufi","sequence":"additional","affiliation":[{"name":"Veterinary Health and Monitoring, Ministry of Environment, Water and Agriculture, Riyadh 11195, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ali","family":"Al-Doweriej","sequence":"additional","affiliation":[{"name":"Veterinary Health and Monitoring, Ministry of Environment, Water and Agriculture, Riyadh 11195, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdulkareem","family":"Al-Shabebi","sequence":"additional","affiliation":[{"name":"Department of Anatomy, College of Veterinary Medicine, King Faisal University, Al-Haa 400, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abd-El Rahman Taha","family":"Hereba","sequence":"additional","affiliation":[{"name":"Department of Virology, Faculty of Veterinary Medicine, Kafrelsheikh University, Kafrelsheikh 33516, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5986-7237","authenticated-orcid":false,"given":"Maged Gomaa","family":"Hemida","sequence":"additional","affiliation":[{"name":"Department of Virology, Faculty of Veterinary Medicine, Kafrelsheikh University, Kafrelsheikh 33516, Egypt"},{"name":"Department of Microbiology, College of Veterinary Medicine, King Faisal University, Al-Haa 400, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1814","DOI":"10.1056\/NEJMoa1211721","article-title":"Isolation of a novel coronavirus from a man with pneumonia in Saudi Arabia","volume":"367","author":"Zaki","year":"2012","journal-title":"N. 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