{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T11:22:07Z","timestamp":1787829727167,"version":"build-2784847793"},"reference-count":28,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union\u2019s Horizon Europe Project","award":["101136346 EUPAHW"],"award-info":[{"award-number":["101136346 EUPAHW"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Epizootic haemorrhagic disease virus (EHDV) is an insect-borne virus that affects ruminants. It has recently emerged as a significant threat to livestock and wildlife, particularly deer and cattle. Since its introduction into Europe in late 2022, severe outbreaks have been reported across several European countries, including Italy, Spain, France, and Portugal. The first confirmed circulation of EHDV in Portugal was reported in July 2023, involving serotype 8 (EHDV-8) in cattle from the municipalities of Moura and Barrancos, in the Beja district of the Alentejo region, alongside concurrent circulation in cervids. Here, we analyse the prevalence and spatial distribution of EHDV during the first recorded outbreaks in Portugal (2023\u20132024), describing its geographic spread across the country and subsequent disappearance by 2025. Higher viral loads were significantly associated with the presence of clinical signs. These findings provide new insights into the epidemiology of EHDV infection and suggest that higher viral loads are associated with the occurrence of clinical disease in naturally infected animals.<\/jats:p>","DOI":"10.3390\/v18090936","type":"journal-article","created":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T10:58:21Z","timestamp":1787828301000},"page":"936","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Nationwide Distribution and Prevalence of Epizootic Haemorrhagic Disease Virus Infection in Portugal (2023\u20132025)"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6246-1983","authenticated-orcid":false,"given":"Silvia C.","family":"Barros","sequence":"first","affiliation":[{"name":"Laboratory of Virology, Strategic Unit for Animal Production Research and Services, National Institute for Agrarian and Veterinary Research, Avenida da Rep\u00fablica, Quinta do Marqu\u00eas, 2780-157 Oeiras, Portugal"},{"name":"NOVA School of Science and Technology, Department of Life Sciences, 2829-516 Caparica, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8561-9846","authenticated-orcid":false,"given":"Fernanda","family":"Ramos","sequence":"additional","affiliation":[{"name":"Laboratory of Virology, Strategic Unit for Animal Production Research and Services, National Institute for Agrarian and Veterinary Research, Avenida da Rep\u00fablica, Quinta do Marqu\u00eas, 2780-157 Oeiras, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"In\u00eas S.","family":"Maia","sequence":"additional","affiliation":[{"name":"Laboratory of Virology, Strategic Unit for Animal Production Research and Services, National Institute for Agrarian and Veterinary Research, Avenida da Rep\u00fablica, Quinta do Marqu\u00eas, 2780-157 Oeiras, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"Catarino","sequence":"additional","affiliation":[{"name":"Laboratory of Virology, Strategic Unit for Animal Production Research and Services, National Institute for Agrarian and Veterinary Research, Avenida da Rep\u00fablica, Quinta do Marqu\u00eas, 2780-157 Oeiras, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0696-7322","authenticated-orcid":false,"given":"F\u00e1bio A.","family":"Abade dos Santos","sequence":"additional","affiliation":[{"name":"Laboratory of Virology, Strategic Unit for Animal Production Research and Services, National Institute for Agrarian and Veterinary Research, Avenida da Rep\u00fablica, Quinta do Marqu\u00eas, 2780-157 Oeiras, Portugal"},{"name":"Veterinary and Animal Research Centre (CECAV), Faculty of Veterinary Medicine, Lus\u00f3fona University, 1749-024 Lisbon, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1835-3077","authenticated-orcid":false,"given":"Ana M.","family":"Henriques","sequence":"additional","affiliation":[{"name":"Laboratory of Virology, Strategic Unit for Animal Production Research and Services, National Institute for Agrarian and Veterinary Research, Avenida da Rep\u00fablica, Quinta do Marqu\u00eas, 2780-157 Oeiras, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana","family":"Duarte","sequence":"additional","affiliation":[{"name":"Laboratory of Virology, Strategic Unit for Animal Production Research and Services, National Institute for Agrarian and Veterinary Research, Avenida da Rep\u00fablica, Quinta do Marqu\u00eas, 2780-157 Oeiras, Portugal"},{"name":"Centre for Interdisciplinary Research in Animal Health (CIISA), 1300-477 Lisbon, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1488-9659","authenticated-orcid":false,"given":"Margarida Dias","family":"Duarte","sequence":"additional","affiliation":[{"name":"Laboratory of Virology, Strategic Unit for Animal Production Research and Services, National Institute for Agrarian and Veterinary Research, Avenida da Rep\u00fablica, Quinta do Marqu\u00eas, 2780-157 Oeiras, Portugal"},{"name":"Centre for Interdisciplinary Research in Animal Health (CIISA), 1300-477 Lisbon, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1016\/j.rvsc.2016.05.013","article-title":"Generation of Virus like Particles for Epizootic Hemorrhagic Disease Virus","volume":"107","author":"Forzan","year":"2016","journal-title":"Res. 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