{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,3]],"date-time":"2026-11-03T12:45:59Z","timestamp":1793709959548,"version":"4.6.1"},"reference-count":47,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T00:00:00Z","timestamp":1777420800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:p>\n                    African swine fever poses an ongoing threat to Eurasian wild pigs and the associated global swine production, with no internationally licensed vaccine available. Live attenuated vaccines like\n                    <jats:italic>ASFV-G-\u0394I177L<\/jats:italic>\n                    demonstrated promising safety and protection in young domestic pigs, but comprehensive safety evaluations in breeding animals are necessary for regulatory licensing in the EU. This study investigated the safety of intramuscular immunization with\n                    <jats:italic>ASFV-G-\u0394I177L<\/jats:italic>\n                    in adult breeding boars (\n                    <jats:italic>Sus scrofa domesticus<\/jats:italic>\n                    ). Eight healthy boars were intramuscularly vaccinated and monitored for clinical manifestation, viral genome and infectious virus in blood, oral fluid, semen, and tissues. Furthermore, ASFV-specific antibodies and effects on semen quality were assessed over an observation period of 28\u202fdays. Clinical signs appeared in all boars at 6\u202fdays post vaccination (dpv), including high fever, lethargy, and anorexia in most animals by 8 dpv. Four animals developed severe disease and were euthanized at humane endpoints or succumbed between 11 and 15 dpv, while four animals recovered. Viral genome was detected in blood, oral fluid, and semen of all animals, with higher loads in succumbed individuals. Infectious\n                    <jats:italic>ASFV-G-\u0394I177L<\/jats:italic>\n                    was found in reproductive tissues, spleens, salivary glands, and semen samples from acutely affected boars and one recovered boar. All boars developed ASFV-targeting antibodies, but titers remained low. Semen quality was significantly reduced after vaccination and failed to recover in surviving boars by 28 dpv. These findings raise concerns regarding vaccine safety in reproductively active boars and highlight the risk of virus transmission through semen.\n                  <\/jats:p>","DOI":"10.3389\/fmicb.2026.1823118","type":"journal-article","created":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T06:01:11Z","timestamp":1777442471000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":8,"title":["Implications for safety: ASFV-G-\u0394I177L vaccine compromises health and semen quality in adult breeding boars"],"prefix":"10.3389","volume":"17","author":[{"given":"Virginia","family":"Friedrichs","sequence":"first","affiliation":[{"name":"Institute for Diagnostic Virology, Friedrich-Loeffler-Institut","place":["Greifswald\u2013Insel Riems, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sten","family":"Calvelage","sequence":"additional","affiliation":[{"name":"Institute for Diagnostic Virology, Friedrich-Loeffler-Institut","place":["Greifswald\u2013Insel Riems, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Theresa","family":"Holzum","sequence":"additional","affiliation":[{"name":"Institute for Diagnostic Virology, Friedrich-Loeffler-Institut","place":["Greifswald\u2013Insel Riems, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisenda","family":"Viaplana","sequence":"additional","affiliation":[{"name":"Zoetis Manufacturing and Research Spain, Finca la Riba, L\u2019Hostalnou de Bianya","place":["Girona, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alicia","family":"Urniza","sequence":"additional","affiliation":[{"name":"Zoetis Manufacturing and Research Spain, Finca la Riba, L\u2019Hostalnou de Bianya","place":["Girona, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Monica","family":"Balasch","sequence":"additional","affiliation":[{"name":"Zoetis Manufacturing and Research Spain, Finca la Riba, L\u2019Hostalnou de Bianya","place":["Girona, Spain"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin","family":"Beer","sequence":"additional","affiliation":[{"name":"Institute for Diagnostic Virology, Friedrich-Loeffler-Institut","place":["Greifswald\u2013Insel Riems, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sandra","family":"Blome","sequence":"additional","affiliation":[{"name":"Institute for Diagnostic Virology, Friedrich-Loeffler-Institut","place":["Greifswald\u2013Insel Riems, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexander","family":"Sch\u00e4fer","sequence":"additional","affiliation":[{"name":"Institute for Diagnostic Virology, Friedrich-Loeffler-Institut","place":["Greifswald\u2013Insel Riems, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,4,29]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"1438","DOI":"10.3390\/pathogens11121438","article-title":"A highly effective African swine fever virus vaccine elicits a memory T cell response in vaccinated swine","volume":"11","author":"Attreed","year":"2022","journal-title":"Pathogens"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"147","DOI":"10.1038\/s41541-025-01208-8","article-title":"Benefit risk considerations for African swine fever virus live attenuated vaccines","volume":"10","author":"Blome","year":"2025","journal-title":"NPJ Vaccines"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"122","DOI":"10.1016\/j.virusres.2012.10.026","article-title":"Pathogenesis of African swine fever in domestic pigs and European wild boar","volume":"173","author":"Blome","year":"2013","journal-title":"Virus Res."},{"key":"ref4","doi-asserted-by":"publisher","first-page":"805","DOI":"10.3390\/pathogens12060805","article-title":"ASF vaccine candidate ASFV-G-\u2206I177L does not exhibit residual virulence in long-term clinical studies","volume":"12","author":"Borca","year":"2023","journal-title":"Pathogens"},{"key":"ref5","doi-asserted-by":"publisher","first-page":"765","DOI":"10.3390\/v13050765","article-title":"ASFV-G-\u2206I177L as an effective oral nasal vaccine against the Eurasia strain of Africa swine fever","volume":"13","author":"Borca","year":"2021","journal-title":"Viruses"},{"key":"ref6","doi-asserted-by":"publisher","first-page":"e02017-19","DOI":"10.1128\/JVI.02017-19","article-title":"Development of a highly effective African swine fever virus vaccine by deletion of the I177L gene results in sterile immunity against the current epidemic Eurasia strain","volume":"94","author":"Borca","year":"2020","journal-title":"J. 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Virol."}],"container-title":["Frontiers in Microbiology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fmicb.2026.1823118\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T06:01:12Z","timestamp":1777442472000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fmicb.2026.1823118\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,29]]},"references-count":47,"alternative-id":["10.3389\/fmicb.2026.1823118"],"URL":"https:\/\/doi.org\/10.3389\/fmicb.2026.1823118","relation":{},"ISSN":["1664-302X"],"issn-type":[{"value":"1664-302X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,29]]},"article-number":"1823118"}}