{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T01:47:33Z","timestamp":1782438453507,"version":"3.54.5"},"reference-count":29,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T00:00:00Z","timestamp":1782345600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Komipharm"},{"name":"National Institute of Wildlife Disease Control and Prevention (NIWDC), Ministry of Climate, Energy and Environment (MCEE) of the Republic of Korea","award":["NIWDC-2025-RP-06"],"award-info":[{"award-number":["NIWDC-2025-RP-06"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background\/Objectives: African swine fever (ASF) is a highly lethal disease of domestic pigs and wild suids that continues to cause substantial economic losses worldwide. Despite recent progress in live attenuated ASF vaccine development, evidence supporting durable protection under repeated exposure conditions representative of endemic settings remains limited. Here, we assessed the long-term safety and protective efficacy of a live attenuated ASFV-G-\u0394I177L\/\u0394LVR vaccine using a repeated-challenge experimental design intended to model re-exposure in ASF-endemic regions. Methods: Vaccinated pigs were subjected to homologous virulent ASF virus challenges at multiple intervals, including repeated challenges (three sequential inoculations) and single challenges administered at 8 and 12 weeks post-vaccination. Results: Across all challenge regimens, vaccinated animals survived and remained clinically healthy, including those receiving three challenges, supporting sustained protection under repeated exposure pressure. Animals challenged at 8 or 12 weeks post-vaccination likewise exhibited complete survival, indicating maintained efficacy through at least 12 weeks. No vaccine-associated adverse clinical outcomes were detected over the study period, and post-challenge viral shedding was minimal. Conclusions: Overall, these data demonstrate that the candidate live attenuated ASF vaccine provides excellent protective efficacy and confers sustained protection against homologous ASF virus infection. This result is expected to be equally applicable under repeated exposure conditions in regions with unstable ASF biosecurity, making it a sufficiently promising model experiment for field application in ASF epidemic areas. However, this is still a vaccine variant, and further studies are planned to evaluate its genomic stability and transmissibility.<\/jats:p>","DOI":"10.3390\/vaccines14070561","type":"journal-article","created":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T00:49:23Z","timestamp":1782434963000},"page":"561","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Repeated and Delayed Homologous Challenge Study Evaluating the Durability of Protection Induced by the Live Attenuated ASF Vaccine Candidate ASFV-G-\u0394I177L\/\u0394LVR"],"prefix":"10.3390","volume":"14","author":[{"given":"Xinghua","family":"Zheng","sequence":"first","affiliation":[{"name":"Central Research & Development Institute, Komipharm International Co., Ltd., Siheung-si 15094, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-4078-8310","authenticated-orcid":false,"given":"Yeonji","family":"Kim","sequence":"additional","affiliation":[{"name":"Wildlife Disease Response Team, National Institute of Wildlife Disease Control and Prevention (NIWDC), Ministry of Climate, Energy and Environment (MCEE), Songamgil 1, Gwangsan-gu, Gwangju 62407, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-7770-5022","authenticated-orcid":false,"given":"Sun A.","family":"Choi","sequence":"additional","affiliation":[{"name":"Central Research & Development Institute, Komipharm International Co., Ltd., Siheung-si 15094, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Su Jin","family":"Lee","sequence":"additional","affiliation":[{"name":"Central Research & Development Institute, Komipharm International Co., Ltd., Siheung-si 15094, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seung Pyo","family":"Shin","sequence":"additional","affiliation":[{"name":"Central Research & Development Institute, Komipharm International Co., Ltd., Siheung-si 15094, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Se Young","family":"Lee","sequence":"additional","affiliation":[{"name":"Central Research & Development Institute, Komipharm International Co., Ltd., Siheung-si 15094, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wonjun","family":"Kim","sequence":"additional","affiliation":[{"name":"Wildlife Disease Response Team, National Institute of Wildlife Disease Control and Prevention (NIWDC), Ministry of Climate, Energy and Environment (MCEE), Songamgil 1, Gwangsan-gu, Gwangju 62407, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seong Cheol","family":"Moon","sequence":"additional","affiliation":[{"name":"Central Research & Development Institute, Komipharm International Co., Ltd., Siheung-si 15094, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yongwoo","family":"Shin","sequence":"additional","affiliation":[{"name":"Wildlife Disease Response Team, National Institute of Wildlife Disease Control and Prevention (NIWDC), Ministry of Climate, Energy and Environment (MCEE), Songamgil 1, Gwangsan-gu, Gwangju 62407, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Do Soon","family":"Kim","sequence":"additional","affiliation":[{"name":"Central Research & Development Institute, Komipharm International Co., Ltd., Siheung-si 15094, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Byung-chul","family":"Shin","sequence":"additional","affiliation":[{"name":"Wildlife Disease Response Team, National Institute of Wildlife Disease Control and Prevention (NIWDC), Ministry of Climate, Energy and Environment (MCEE), Songamgil 1, Gwangsan-gu, Gwangju 62407, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sua","family":"Choi","sequence":"additional","affiliation":[{"name":"Wildlife Disease Response Team, National Institute of Wildlife Disease Control and Prevention (NIWDC), Ministry of Climate, Energy and Environment (MCEE), Songamgil 1, Gwangsan-gu, Gwangju 62407, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ji-yun","family":"Sung","sequence":"additional","affiliation":[{"name":"Wildlife Disease Response Team, National Institute of Wildlife Disease Control and Prevention (NIWDC), Ministry of Climate, Energy and Environment (MCEE), Songamgil 1, Gwangsan-gu, Gwangju 62407, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Garam","family":"Kim","sequence":"additional","affiliation":[{"name":"Wildlife Disease Response Team, National Institute of Wildlife Disease Control and Prevention (NIWDC), Ministry of Climate, Energy and Environment (MCEE), Songamgil 1, Gwangsan-gu, Gwangju 62407, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Weonhwa","family":"Jheong","sequence":"additional","affiliation":[{"name":"Wildlife Disease Response Team, National Institute of Wildlife Disease Control and Prevention (NIWDC), Ministry of Climate, Energy and Environment (MCEE), Songamgil 1, Gwangsan-gu, Gwangju 62407, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-9734-5852","authenticated-orcid":false,"given":"Jung Hyang","family":"Sur","sequence":"additional","affiliation":[{"name":"Central Research & Development Institute, Komipharm International Co., Ltd., Siheung-si 15094, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1016\/j.virusres.2019.04.002","article-title":"African swine fever virus evasion of host defences","volume":"266","author":"Dixon","year":"2019","journal-title":"Virus Res."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"58","DOI":"10.4102\/jsava.v80i2.172","article-title":"Review of African swine fever: Transmission, spread and control","volume":"80","author":"Penrith","year":"2009","journal-title":"J. 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