{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T20:05:43Z","timestamp":1792872343553,"version":"4.5.0"},"reference-count":34,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,8,10]],"date-time":"2023-08-10T00:00:00Z","timestamp":1691625600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001655","name":"German Academic Exchange Service","doi-asserted-by":"publisher","award":["0001803286"],"award-info":[{"award-number":["0001803286"]}],"id":[{"id":"10.13039\/501100001655","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Prevalence of progressive feline leukaemia virus (FeLV) infection is known to still be high in cats in Europe, especially in Southern Europe, but the prevalence of other outcomes of FeLV infection has not been determined in most countries. The present study aimed to investigate the prevalence of progressive, regressive, abortive, and focal infection in four European countries, two with a high (Italy, Portugal) and two with a low expected prevalence (Germany, France). Blood samples of 934 cats (Italy: 269; Portugal: 240; France: 107; Germany: 318) were evaluated for the p27 antigen, as well as anti-whole virus, anti-SU, and anti-p15E antibodies by enzyme-linked immunosorbent assay (ELISA) in serum and for proviral DNA by quantitative polymerase chain reaction (qPCR) in whole blood. Positive p27 antigen ELISA results were confirmed by reverse transcriptase-qPCR (RT-qPCR) detecting viral RNA in saliva swabs and\/or blood. The outcome of FeLV infection was categorised as progressive (antigen-positive, provirus-positive), regressive (antigen-negative, provirus-positive), abortive (antigen- and provirus-negative, antibody-positive), and focal (antigen-positive, provirus-negative) infection. Overall FeLV prevalence was 21.2% in Italy, 20.4% in Portugal, 9.5% in Germany, and 9.3% in France. Prevalence of progressive, regressive, abortive, and focal infection in Italy was 7.8%, 4.5%, 6.3%, and 2.6%; in Portugal 3.8%, 8.3%, 6.7%, and 1.7%; in Germany 1.9%, 1.3%, 3.5%, and 2.8%; in France 1.9%, 3.7%, 2.8%, and 0.9%, respectively. In conclusion, overall FeLV prevalence is still very high, especially in Southern European countries. Therefore, testing, separation of infected cats, and vaccination are still important measures to reduce the risk of FeLV infection.<\/jats:p>","DOI":"10.3390\/v15081718","type":"journal-article","created":{"date-parts":[[2023,8,11]],"date-time":"2023-08-11T10:20:16Z","timestamp":1691749216000},"page":"1718","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Prevalence of Different Courses of Feline Leukaemia Virus Infection in Four European Countries"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1012-5977","authenticated-orcid":false,"given":"Juliana","family":"Giselbrecht","sequence":"first","affiliation":[{"name":"LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"St\u00e9phanie","family":"J\u00e4hne","sequence":"additional","affiliation":[{"name":"LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mich\u00e8le","family":"Bergmann","sequence":"additional","affiliation":[{"name":"LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3609-2416","authenticated-orcid":false,"given":"Marina L.","family":"Meli","sequence":"additional","affiliation":[{"name":"Clinical Laboratory, Department of Clinical Diagnostics and Services, and Centre for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benita","family":"Pineroli","sequence":"additional","affiliation":[{"name":"Clinical Laboratory, Department of Clinical Diagnostics and Services, and Centre for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eva","family":"Boenzli","sequence":"additional","affiliation":[{"name":"Clinical Laboratory, Department of Clinical Diagnostics and Services, and Centre for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-8288-2009","authenticated-orcid":false,"given":"Svenja","family":"Teichmann-Knorrn","sequence":"additional","affiliation":[{"name":"Veterinary Clinic Oberhaching, 82041 Oberhaching, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yury","family":"Zablotski","sequence":"additional","affiliation":[{"name":"LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3169-4194","authenticated-orcid":false,"given":"Maria-Grazia","family":"Pennisi","sequence":"additional","affiliation":[{"name":"Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicolas","family":"Layachi","sequence":"additional","affiliation":[{"name":"Layachi Veterinary Clinic, 33300 Bordeaux, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7775-7680","authenticated-orcid":false,"given":"Rodrigo","family":"Serra","sequence":"additional","affiliation":[{"name":"Investigacao Veterinaria Independente, 1700-119 Lisbon, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefano","family":"Bo","sequence":"additional","affiliation":[{"name":"Ambulatorio Veterinario Bo-Ferro, 10123 Turin, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9750-4296","authenticated-orcid":false,"given":"Regina","family":"Hofmann-Lehmann","sequence":"additional","affiliation":[{"name":"Clinical Laboratory, Department of Clinical Diagnostics and Services, and Centre for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5256-863X","authenticated-orcid":false,"given":"Katrin","family":"Hartmann","sequence":"additional","affiliation":[{"name":"LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1013","DOI":"10.1016\/j.cvsm.2020.05.006","article-title":"What\u2019s new in feline leukemia virus infection","volume":"50","author":"Hartmann","year":"2020","journal-title":"Vet. 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