{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T11:07:58Z","timestamp":1788865678044,"version":"build-2803163510"},"reference-count":45,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,7,15]],"date-time":"2022-07-15T00:00:00Z","timestamp":1657843200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"INIA-MAPA agreement","award":["EG17-141"],"award-info":[{"award-number":["EG17-141"]}]}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["Viruses"],"abstract":"<jats:p>This study described the clinical, virological, and serological responses of immunologically na\u00efve and vaccinated horses to African horse sickness virus (AHSV) serotype 9. Na\u00efve horses developed a clinical picture resembling the cardiac form of African horse sickness. This was characterized by inappetence, reduced activity, and hyperthermia leading to lethargy and immobility\u2013recumbency by days 9\u201310 post-infection, an end-point criteria for euthanasia. After challenge, unvaccinated horses were viremic from days 3 or 4 post-infection till euthanasia, as detected by serogroup-specific (GS) real time RT-PCR (rRT-PCR) and virus isolation. Virus isolation, antigen ELISA, and GS-rRT-PCR also demonstrated high sensitivity in the post-mortem detection of the pathogen. After infection, serogroup-specific VP7 antibodies were undetectable by blocking ELISA (b-ELISA) in 2 out of 3 unvaccinated horses during the course of the disease (9\u201310 dpi). Vaccinated horses did not show significant side effects post-vaccination and were largely asymptomatic after the AHSV-9 challenge. VP7-specific antibodies could not be detected by the b-ELISA until day 21 and day 30 post-inoculation, respectively. Virus neutralizing antibody titres were low or even undetectable for specific serotypes in the vaccinated horses. Virus isolation and GS-rRT-PCR detected the presence of AHSV vaccine strains genomes and infectious vaccine virus after vaccination and challenge. This study established an experimental infection model of AHSV-9 in horses and characterized the main clinical, virological, and immunological parameters in both immunologically na\u00efve and vaccinated horses using standardized bio-assays.<\/jats:p>","DOI":"10.3390\/v14071545","type":"journal-article","created":{"date-parts":[[2022,7,18]],"date-time":"2022-07-18T01:53:22Z","timestamp":1658109202000},"page":"1545","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Clinical, Virological and Immunological Responses after Experimental Infection with African Horse Sickness Virus Serotype 9 in Immunologically Na\u00efve and Vaccinated Horses"],"prefix":"10.3390","volume":"14","author":[{"given":"Manuel","family":"Dur\u00e1n-Ferrer","sequence":"first","affiliation":[{"name":"Laboratorio Central de Veterinaria (LCV), Ministry of Agriculture, Fisheries and Food, Ctra. M-106, pk 1,4, 28110 Algete, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rub\u00e9n","family":"Villalba","sequence":"additional","affiliation":[{"name":"Laboratorio Central de Veterinaria (LCV), Ministry of Agriculture, Fisheries and Food, Ctra. M-106, pk 1,4, 28110 Algete, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paloma","family":"Fern\u00e1ndez-Pacheco","sequence":"additional","affiliation":[{"name":"Centro de Investigaci\u00f3n en Sanidad Animal (CISA), Instituto Nacional de Investigaci\u00f3n y Tecnolog\u00eda Agraria y Alimentaria (INIA-CSIC), Ctra. M-106, pk 8,1, 28130 Valdeolmos, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristina","family":"Tena-Tom\u00e1s","sequence":"additional","affiliation":[{"name":"Tecnolog\u00edas y Servicios Agrarios, S.A, (TRAGSATEC), 28006 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2125-9743","authenticated-orcid":false,"given":"Miguel-\u00c1ngel","family":"Jim\u00e9nez-Clavero","sequence":"additional","affiliation":[{"name":"Centro de Investigaci\u00f3n en Sanidad Animal (CISA), Instituto Nacional de Investigaci\u00f3n y Tecnolog\u00eda Agraria y Alimentaria (INIA-CSIC), Ctra. 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M-106, pk 1,4, 28110 Algete, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9919-0112","authenticated-orcid":false,"given":"Jovita","family":"Fern\u00e1ndez-Pinero","sequence":"additional","affiliation":[{"name":"Centro de Investigaci\u00f3n en Sanidad Animal (CISA), Instituto Nacional de Investigaci\u00f3n y Tecnolog\u00eda Agraria y Alimentaria (INIA-CSIC), Ctra. M-106, pk 8,1, 28130 Valdeolmos, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6044-2968","authenticated-orcid":false,"given":"Marisa","family":"Arias","sequence":"additional","affiliation":[{"name":"Centro de Investigaci\u00f3n en Sanidad Animal (CISA), Instituto Nacional de Investigaci\u00f3n y Tecnolog\u00eda Agraria y Alimentaria (INIA-CSIC), Ctra. M-106, pk 8,1, 28130 Valdeolmos, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3453-8557","authenticated-orcid":false,"given":"Javier","family":"Castillo-Olivares","sequence":"additional","affiliation":[{"name":"Laboratory of Viral Zoonotics, Department of Veterinary Medicine, University of Cambridge, Cambridge CB3 0ES, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Montserrat","family":"Ag\u00fcero","sequence":"additional","affiliation":[{"name":"Laboratorio Central de Veterinaria (LCV), Ministry of Agriculture, Fisheries and Food, Ctra. M-106, pk 1,4, 28110 Algete, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,15]]},"reference":[{"key":"ref_1","unstructured":"Tena-Tom\u00e1s, C., Rocha, A., Buitrago, D., and Ag\u00fcero, M. (2014, January 5\u20137). 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