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Giselbrecht J, Jähne S, Bergmann M, Meli ML, Teichmann-Knorrn S, Zablotski Y, Pennisi MG, Layachi N, Serra R, Bo S, Hofmann-Lehmann R, Hartmann K. Evaluation of a Revised Point-of-Care Test for the Detection of Feline Leukaemia p27 Antigen and Anti-p15E Antibodies in Cats. Viruses 2024; 16:614. [PMID: 38675954 PMCID: PMC11054206 DOI: 10.3390/v16040614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 04/10/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024] Open
Abstract
The first point-of-care (PoC) test (v-RetroFel®; modified version 2021) determining the presence of FeLV p27 antigen and FeLV anti-p15E antibodies has become recently commercially available to identify different feline leukaemia virus (FeLV) infection outcomes. This study aimed to assess this PoC test's performance concerning FeLV p27 antigen and FeLV anti-p15E antibody detection. Sensitivity, specificity, positive and negative predictive values (PPV, NPV) were assessed after ten minutes (recommended) and 20 min (prolonged) incubation times. The test results were evaluated as either positive or negative. Serum samples from 934 cats were included, originating from Italy (n = 269), Portugal (n = 240), Germany (n = 318), and France (n = 107). FeLV p27 antigen and anti-p15E antibodies were measured by reference standard ELISAs and compared to the PoC test results. The PoC test was easy to perform and the results easy to interpret. Sensitivity and specificity for FeLV p27 antigen were 82.8% (PPV: 57.8%) and 96.0% (NPV: 98.8%) after both, ten and 20 minues of incubation time. Sensitivity and specificity for anti-p15E antibodies were 31.4% (PPV: 71.6%) and 96.9% (NPV: 85.1%) after ten minutes incubation time; sensitivity was improved by a prolonged incubation time (20 min) to 40.0% (PPV: 76.3%), while specificity remained the same (96.9%, NPV: 86.7%). Despite the improved sensitivity using the prolonged incubation time, lower than ideal sensitivities for both p27 antigen and especially anti-p15E antibodies were found, indicating that the PoC test in its current version needs further improvement prior to application in the field.
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Affiliation(s)
- Juliana Giselbrecht
- LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany
| | - Stéphanie Jähne
- LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany
| | - Michèle Bergmann
- LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany
| | - Marina L. Meli
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | | | - Yury Zablotski
- LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany
| | | | | | - Rodrigo Serra
- Investigacao Veterinaria Independente, 1700-119 Lisbon, Portugal
| | - Stefano Bo
- Ambulatorio Veterinario Bo-Ferro, 10123 Turin, Italy
| | - Regina Hofmann-Lehmann
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Katrin Hartmann
- LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany
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2
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Meli ML, Pineroli B, Geisser E, Hofmann-Lehmann R. Prospective Investigation of Feline Leukemia Virus Infection in Stray Cats Subjected to a Trap-Neuter-Return Program in Switzerland. Viruses 2024; 16:394. [PMID: 38543760 PMCID: PMC10975613 DOI: 10.3390/v16030394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2024] [Revised: 02/24/2024] [Accepted: 02/28/2024] [Indexed: 05/23/2024] Open
Abstract
Feline leukemia virus (FeLV) remains a serious concern in some countries despite advances in diagnostics and vaccines. FeLV-infected cats often have reduced lifespans due to FeLV-associated diseases. The infection is transmitted through social interactions. While Northern European countries have reported a decrease in FeLV among pet cats, Switzerland's rates remain stagnant at 2.7% (2016/17: 95% CI 1.4-5.2%). Research on FeLV in Swiss stray cats has been lacking, even though these animals could serve as a virus reservoir. Sampling stray cats that do not receive regular veterinary care can be challenging. Collaboration with the Swiss Network for Animal Protection (NetAP) allowed for the prospective collection of saliva samples from 1711 stray cats during a trap-neuter-return program from 2019 to 2023. These samples were tested for FeLV RNA using RT-qPCR as a measure for antigenemia. Viral RNA was detected in 4.0% (95% CI 3.1-5.0%) of the samples, with 7.7% (95% CI 4.9-11.3%) in sick cats and 3.3% (95% CI 2.4-4.4%) in healthy ones. We identified three geographically independent hotspots with alarmingly high FeLV infection rates in stray cats (up to 70%). Overall, including the previous data of privately owned cats, FeLV-positive cats were scattered throughout Switzerland in 24/26 cantons. Our findings underscore welfare concerns for FeLV infections among stray cats lacking veterinary attention, highlighting the potential risk of infection to other free-roaming cats, including those privately owned. This emphasizes the critical significance of vaccinating all cats with outdoor access against FeLV and developing programs to protect cats from FeLV infections.
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Affiliation(s)
- Marina L. Meli
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland; (M.L.M.)
| | - Benita Pineroli
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland; (M.L.M.)
| | - Esther Geisser
- Network for Animal Protection (NetAP), 8133 Esslingen, Switzerland;
| | - Regina Hofmann-Lehmann
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland; (M.L.M.)
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3
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Giselbrecht J, Jähne S, Bergmann M, Meli ML, Pineroli B, Boenzli E, Teichmann-Knorrn S, Zablotski Y, Pennisi MG, Layachi N, Serra R, Bo S, Hofmann-Lehmann R, Hartmann K. Prevalence of Different Courses of Feline Leukaemia Virus Infection in Four European Countries. Viruses 2023; 15:1718. [PMID: 37632060 PMCID: PMC10459464 DOI: 10.3390/v15081718] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 08/07/2023] [Accepted: 08/08/2023] [Indexed: 08/27/2023] Open
Abstract
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.
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Affiliation(s)
- Juliana Giselbrecht
- LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany; (S.J.); (M.B.); (Y.Z.); (K.H.)
| | - Stéphanie Jähne
- LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany; (S.J.); (M.B.); (Y.Z.); (K.H.)
| | - Michèle Bergmann
- LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany; (S.J.); (M.B.); (Y.Z.); (K.H.)
| | - Marina L. Meli
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Centre for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland; (M.L.M.); (B.P.); (E.B.); (R.H.-L.)
| | - Benita Pineroli
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Centre for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland; (M.L.M.); (B.P.); (E.B.); (R.H.-L.)
| | - Eva Boenzli
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Centre for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland; (M.L.M.); (B.P.); (E.B.); (R.H.-L.)
| | | | - Yury Zablotski
- LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany; (S.J.); (M.B.); (Y.Z.); (K.H.)
| | | | | | - Rodrigo Serra
- Investigacao Veterinaria Independente, 1700-119 Lisbon, Portugal;
| | - Stefano Bo
- Ambulatorio Veterinario Bo-Ferro, 10123 Turin, Italy;
| | - Regina Hofmann-Lehmann
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Centre for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland; (M.L.M.); (B.P.); (E.B.); (R.H.-L.)
| | - Katrin Hartmann
- LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, 80539 Munich, Germany; (S.J.); (M.B.); (Y.Z.); (K.H.)
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Ortiz R, Barajas A, Pons-Grífols A, Trinité B, Tarrés-Freixas F, Rovirosa C, Urrea V, Barreiro A, Gonzalez-Tendero A, Cardona M, Ferrer L, Clotet B, Carrillo J, Aguilar-Gurrieri C, Blanco J. Exploring FeLV-Gag-Based VLPs as a New Vaccine Platform-Analysis of Production and Immunogenicity. Int J Mol Sci 2023; 24:ijms24109025. [PMID: 37240371 DOI: 10.3390/ijms24109025] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 05/11/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023] Open
Abstract
Feline leukemia virus (FeLV) is one of the most prevalent infectious diseases in domestic cats. Although different commercial vaccines are available, none of them provides full protection. Thus, efforts to design a more efficient vaccine are needed. Our group has successfully engineered HIV-1 Gag-based VLPs that induce a potent and functional immune response against the HIV-1 transmembrane protein gp41. Here, we propose to use this concept to generate FeLV-Gag-based VLPs as a novel vaccine strategy against this retrovirus. By analogy to our HIV-1 platform, a fragment of the FeLV transmembrane p15E protein was exposed on FeLV-Gag-based VLPs. After optimization of Gag sequences, the immunogenicity of the selected candidates was evaluated in C57BL/6 and BALB/c mice, showing strong cellular and humoral responses to Gag but failing to generate anti-p15E antibodies. Altogether, this study not only tests the versatility of the enveloped VLP-based vaccine platform but also sheds light on FeLV vaccine research.
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Affiliation(s)
- Raquel Ortiz
- AIDS Research Institute, IrsiCaixa, Campus Can Ruti, 08916 Badalona, Spain
- Doctorate School, Microbiology Department, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Ana Barajas
- AIDS Research Institute, IrsiCaixa, Campus Can Ruti, 08916 Badalona, Spain
- Doctorate School, Medicine Department, University of Vic-Central University of Catalonia (UVic-UCC), 08500 Vic, Spain
| | - Anna Pons-Grífols
- AIDS Research Institute, IrsiCaixa, Campus Can Ruti, 08916 Badalona, Spain
- Doctorate School, Microbiology Department, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Benjamin Trinité
- AIDS Research Institute, IrsiCaixa, Campus Can Ruti, 08916 Badalona, Spain
| | | | - Carla Rovirosa
- AIDS Research Institute, IrsiCaixa, Campus Can Ruti, 08916 Badalona, Spain
| | - Victor Urrea
- AIDS Research Institute, IrsiCaixa, Campus Can Ruti, 08916 Badalona, Spain
| | | | | | | | | | - Bonaventura Clotet
- AIDS Research Institute, IrsiCaixa, Campus Can Ruti, 08916 Badalona, Spain
- Doctorate School, Medicine Department, University of Vic-Central University of Catalonia (UVic-UCC), 08500 Vic, Spain
- Infectious Diseases Department, Germans Trias I Pujol Hospital, 08916 Badalona, Spain
| | - Jorge Carrillo
- AIDS Research Institute, IrsiCaixa, Campus Can Ruti, 08916 Badalona, Spain
- CIBERINFEC, ISCIII, 28029 Madrid, Spain
| | | | - Julià Blanco
- AIDS Research Institute, IrsiCaixa, Campus Can Ruti, 08916 Badalona, Spain
- Doctorate School, Microbiology Department, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
- Doctorate School, Medicine Department, University of Vic-Central University of Catalonia (UVic-UCC), 08500 Vic, Spain
- CIBERINFEC, ISCIII, 28029 Madrid, Spain
- Germans Trias I Pujol Research Institute (IGTP), Campus Can Ruti, 08916 Badalona, Spain
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5
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Westman ME, Giselbrecht J, Norris JM, Malik R, Green J, Burton-Bradley E, Cheang A, Meili T, Meli ML, Hartmann K, Hofmann-Lehmann R. Field Performance of a Rapid Test to Detect Progressive, Regressive, and Abortive Feline Leukemia Virus Infections in Domestic Cats in Australia and Germany. Viruses 2023; 15:v15020491. [PMID: 36851705 PMCID: PMC9967048 DOI: 10.3390/v15020491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 01/30/2023] [Accepted: 01/31/2023] [Indexed: 02/12/2023] Open
Abstract
Different feline leukemia virus (FeLV) infection outcomes are possible in cats following natural exposure, such as progressive infections (persistent viremia), regressive infections (transient or no viremia followed by proviral persistence) and abortive infections (presence of only antibodies). Laboratory-based testing is currently required for categorization of infection outcomes in cats. The aim of this study was to evaluate the field performance of a novel, rapid, combination point-of-care (PoC) test kit commercially available in Europe (v-RetroFel®Ag/Ab; 2020-2021 version) to determine different FeLV infection outcomes by concurrent detection of FeLV antigen (p27) and antibodies against FeLV transmembrane envelope protein (p15E). A secondary aim was to evaluate the performance of the same test kit (v-RetroFel®FIV) to determine positive/negative feline immunodeficiency virus (FIV) infection status by the detection of antibodies to FIV capsid protein (p24) and transmembrane glycoprotein (gp40). Two cohorts of domestic cats were recruited and tested with v-RetroFel® using plasma or serum, including cats in Australia (n = 200) and cats in Germany (n = 170). Results from p27 antigen PoC testing, proviral DNA PCR, and neutralizing antibody testing or testing for antibodies against non-glycosylated surface unit envelope protein (p45) were used to assign cats to groups according to different FeLV infection outcomes. Testing with a laboratory-based FeLV p15E antibody ELISA was also performed for comparison. In the first cohort, v-RetroFel®Ag/Ab correctly identified 89% (109/122) FeLV-unexposed cats and 91% (21/23) progressive infections, but no regressive (0/23) or abortive (0/32) infections. In the second cohort, v-RetroFel®Ag/Ab correctly identified 94% (148/158) FeLV-unexposed cats and 100% (4/4) progressive infections, but no regressive (0/2) and only 17% (1/6) abortive infections. There was test agreement between v-RetroFel®Ab and the p15E laboratory ELISA in 58.9% of samples. As a secondary outcome of this study, the sensitivity and specificity of v-RetroFel®FIV testing in cohort 1 were 94.7% (18/19) and 98.3% (178/181), and in cohort 2, 30.0% (3/10) and 100.0% (160/160), respectively. Prior history of FIV vaccination did not produce any false-positive FIV results. In conclusion, v-RetroFel®Ag/Ab (2020-2021 version) was unable to accurately determine different FeLV infection outcomes in the field. Improvements of the test prior to application to field samples are required.
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Affiliation(s)
- Mark E. Westman
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW 2006, Australia
- Correspondence:
| | - Juliana Giselbrecht
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine LMU Munich, Veterinaerstrasse 13, 80539 Munich, Germany
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, The University of Zurich, CH-8057 Zurich, Switzerland
| | - Jacqueline M. Norris
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW 2006, Australia
- The Sydney Institute for Infectious Diseases, The University of Sydney, Sydney, NSW 2006, Australia
| | - Richard Malik
- Centre for Veterinary Education, The University of Sydney, Sydney, NSW 2006, Australia
- School of Veterinary and Animal Science, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
| | - Jennifer Green
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW 2006, Australia
| | - Elle Burton-Bradley
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW 2006, Australia
| | - Ashley Cheang
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW 2006, Australia
| | - Theres Meili
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, The University of Zurich, CH-8057 Zurich, Switzerland
| | - Marina L. Meli
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, The University of Zurich, CH-8057 Zurich, Switzerland
| | - Katrin Hartmann
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine LMU Munich, Veterinaerstrasse 13, 80539 Munich, Germany
| | - Regina Hofmann-Lehmann
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, The University of Zurich, CH-8057 Zurich, Switzerland
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6
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Abstract
Vaccines protect cats from serious diseases by inducing antibodies and cellular immune responses. Primary vaccinations and boosters are given according to vaccination guidelines provided by industry and veterinary organizations, based on minimal duration of immunity (DOI). For certain diseases, particularly feline panleukopenia, antibody titres correlate with protection. For feline calicivirus and feline herpesvirus, a similar correlation is absent, or less clear. In this review, the European Advisory Board on Cat Diseases (ABCD) presents current knowledge and expert opinion on the use of antibody testing in different situations. Antibody testing can be performed either in diagnostic laboratories, or in veterinary practice using point of care (POC) tests, and can be applied for several purposes, such as to provide evidence that a successful immune response was induced following vaccination. In adult cats, antibody test results can inform the appropriate re-vaccination interval. In shelters, antibody testing can support the control of FPV outbreaks by identifying potentially unprotected cats. Antibody testing has also been proposed to support decisions on optimal vaccination schedules for the individual kitten. However, such testing is still expensive and it is considered impractical to monitor the decline of maternally derived antibodies.
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Giselbrecht J, Bergmann M, Hofmann-Lehmann R, Hartmann K. [Feline leukemia virus infection - a guide to diagnosis]. TIERARZTLICHE PRAXIS. AUSGABE K, KLEINTIERE/HEIMTIERE 2022; 50:198-212. [PMID: 35790167 DOI: 10.1055/a-1845-0750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Feline leukemia virus (FeLV) infection affects cats worldwide. The course of FeLV infection can change and vary over time. The complex pathogenesis, the availability of many different testing methods, and the interpretation of test results are often challenging for veterinarians. Cats with progressive infection (persistently p27 antigen-positive) shed FeLV mainly through saliva and are therefore considered a source of infection for uninfected cats. Diagnosing regressive infection is often challenging, since it usually cannot be detected by commonly used point of care-tests (p27 antigen test) and thus, it often remains undetected. Nevertheless, cats with regressive infection are FeLV carriers (provirus-positive) and when the immune system is suppressed, reactivation of the infection and FeLV-associated clinical signs can occur. Abortively infected cats are never viraemic, do not shed virus, and do not develop clinical signs. Abortive infection can solely be diagnosed via antibodies detection in blood. A new point-of-care test for the identification of antibodies against FeLV p15E antigen has recently been introduced on the European market and is currently being evaluated.
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Affiliation(s)
| | - Michèle Bergmann
- Medizinische Kleintierklinik, Ludwig-Maximilians-Universität München
| | | | - Katrin Hartmann
- Medizinische Kleintierklinik, Ludwig-Maximilians-Universität München
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8
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Ryser-Degiorgis MP, Marti I, Pisano SRR, Pewsner M, Wehrle M, Breitenmoser-Würsten C, Origgi FC, Kübber-Heiss A, Knauer F, Posautz A, Eberspächer-Schweda M, Huder JB, Böni J, Kubacki J, Bachofen C, Riond B, Hofmann-Lehmann R, Meli ML. Management of Suspected Cases of Feline Immunodeficiency Virus Infection in Eurasian Lynx ( Lynx lynx) During an International Translocation Program. Front Vet Sci 2021; 8:730874. [PMID: 34760956 PMCID: PMC8573149 DOI: 10.3389/fvets.2021.730874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 09/10/2021] [Indexed: 11/22/2022] Open
Abstract
The Eurasian lynx (Lynx lynx) population in Switzerland serves as a source for reintroductions in neighboring countries. In 2016–2017, three lynx from the same geographical area were found seropositive for feline immunodeficiency virus (FIV) in the framework of an international translocation program. This novel finding raised questions about the virus origin and pathogenicity to lynx, the emerging character of the infection, and the interpretation of serological results in other lynx caught for translocation. Archived serum samples from 84 lynx captured in 2001–2016 were retrospectively tested for FIV antibodies by Western blot. All archived samples were FIV-negative. The three seropositive lynx were monitored in quarantine enclosures prior to euthanasia and necropsy. They showed disease signs, pathological findings, and occurrence of co-infections reminding of those described in FIV-infected domestic cats. All attempts to isolate and characterize the virus failed but serological data and spatiotemporal proximity of the cases suggested emergence of a lentivirus with antigenic and pathogenic similarities to FIV in the Swiss lynx population. A decision scheme was developed to minimize potential health risks posed by FIV infection, both in the recipient and source lynx populations, considering conservation goals, animal welfare, and the limited action range resulting from local human conflicts. Development and implementation of a cautious decision scheme was particularly challenging because FIV pathogenic potential in lynx was unclear, negative FIV serological results obtained within the first weeks after infection are unpredictable, and neither euthanasia nor repatriation of multiple lynx was acceptable options. The proposed scheme distinguished between three scenarios: release at the capture site, translocation, or euthanasia. Until April 2021, none of the 40 lynx newly captured in Switzerland tested FIV-seropositive. Altogether, seropositivity to FIV was documented in none of 124 lynx tested at their first capture, but three of them seroconverted in 2016–2017. Diagnosis of FIV infection in the three seropositive lynx remains uncertain, but clinical observations and pathological findings confirmed that euthanasia was appropriate. Our experiences underline the necessity to include FIV in pathogen screenings of free-ranging European wild felids, the importance of lynx health monitoring, and the usefulness of health protocols in wildlife translocation.
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Affiliation(s)
| | - Iris Marti
- Institute for Fish and Wildlife Health, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Simone R R Pisano
- Institute for Fish and Wildlife Health, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Mirjam Pewsner
- Institute for Fish and Wildlife Health, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | | | | | - Francesco C Origgi
- Institute for Fish and Wildlife Health, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Anna Kübber-Heiss
- Research Institute of Wildlife Ecology, University of Vienna, Vienna, Austria
| | - Felix Knauer
- Research Institute of Wildlife Ecology, University of Vienna, Vienna, Austria
| | - Annika Posautz
- Research Institute of Wildlife Ecology, University of Vienna, Vienna, Austria
| | - Matthias Eberspächer-Schweda
- Dentistry and Oral Surgery Service, Department/Hospital for Companion Animals and Horses, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Jon B Huder
- Swiss National Center for Retroviruses, Institute of Medical Virology, University of Zurich, Zurich, Switzerland
| | - Jürg Böni
- Swiss National Center for Retroviruses, Institute of Medical Virology, University of Zurich, Zurich, Switzerland
| | - Jakub Kubacki
- Institute of Virology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Claudia Bachofen
- Institute of Virology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Barbara Riond
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Regina Hofmann-Lehmann
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Marina L Meli
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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9
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Klaus J, Meli ML, Willi B, Nadeau S, Beisel C, Stadler T, Egberink H, Zhao S, Lutz H, Riond B, Rösinger N, Stalder H, Renzullo S, Hofmann-Lehmann R. Detection and Genome Sequencing of SARS-CoV-2 in a Domestic Cat with Respiratory Signs in Switzerland. Viruses 2021; 13:496. [PMID: 33802899 PMCID: PMC8002591 DOI: 10.3390/v13030496] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/02/2021] [Accepted: 03/12/2021] [Indexed: 02/06/2023] Open
Abstract
Since the emergence of coronavirus disease (COVID-19) in late 2019, domestic cats have been demonstrated to be susceptible to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) under natural and experimental conditions. As pet cats often live in very close contact with their owners, it is essential to investigate SARS-CoV-2 infections in cats in a One-Health context. This study reports the first SARS-CoV-2 infection in a cat in a COVID-19-affected household in Switzerland. The cat (Cat 1) demonstrated signs of an upper respiratory tract infection, including sneezing, inappetence, and apathy, while the cohabiting cat (Cat 2) remained asymptomatic. Nasal, oral, fecal, fur, and environmental swab samples were collected twice from both cats and analyzed by RT-qPCR for the presence of SARS-CoV-2 viral RNA. Both nasal swabs from Cat 1 tested positive. In addition, the first oral swab from Cat 2 and fur and bedding swabs from both cats were RT-qPCR positive. The fecal swabs tested negative. The infection of Cat 1 was confirmed by positive SARS-CoV-2 S1 receptor binding domain (RBD) antibody testing and neutralizing activity in a surrogate assay. The viral genome sequence from Cat 1, obtained by next generation sequencing, showed the closest relation to a human sequence from the B.1.1.39 lineage, with one single nucleotide polymorphism (SNP) difference. This study demonstrates not only SARS-CoV-2 infection of a cat from a COVID-19-affected household but also contamination of the cats' fur and bed with viral RNA. Our results are important to create awareness that SARS-CoV-2 infected people should observe hygienic measures to avoid infection and contamination of animal cohabitants.
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Affiliation(s)
- Julia Klaus
- Clinical Laboratory, Vetsuisse Faculty, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland; (M.L.M.); (H.L.); (B.R.); (R.H.-L.)
| | - Marina L. Meli
- Clinical Laboratory, Vetsuisse Faculty, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland; (M.L.M.); (H.L.); (B.R.); (R.H.-L.)
| | - Barbara Willi
- Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland; (B.W.); (N.R.)
| | - Sarah Nadeau
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; (S.N.); (C.B.); (T.S.)
- SIB Swiss Institute of Bioinformatics, 4058 Basel, Switzerland
| | - Christian Beisel
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; (S.N.); (C.B.); (T.S.)
| | - Tanja Stadler
- Department of Biosystems Science and Engineering, ETH Zurich, 4058 Basel, Switzerland; (S.N.); (C.B.); (T.S.)
- SIB Swiss Institute of Bioinformatics, 4058 Basel, Switzerland
| | | | - Herman Egberink
- Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, University of Utrecht, 3584 CL Utrecht, The Netherlands; (H.E.); (S.Z.)
| | - Shan Zhao
- Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, University of Utrecht, 3584 CL Utrecht, The Netherlands; (H.E.); (S.Z.)
| | - Hans Lutz
- Clinical Laboratory, Vetsuisse Faculty, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland; (M.L.M.); (H.L.); (B.R.); (R.H.-L.)
| | - Barbara Riond
- Clinical Laboratory, Vetsuisse Faculty, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland; (M.L.M.); (H.L.); (B.R.); (R.H.-L.)
| | - Nina Rösinger
- Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland; (B.W.); (N.R.)
| | - Hanspeter Stalder
- Institute for Virology and Immunology IVI, Sensemattstrasse 293, 3147 Mittelhäusern, Switzerland; (H.S.); (S.R.)
- Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland
| | - Sandra Renzullo
- Institute for Virology and Immunology IVI, Sensemattstrasse 293, 3147 Mittelhäusern, Switzerland; (H.S.); (S.R.)
- Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland
| | - Regina Hofmann-Lehmann
- Clinical Laboratory, Vetsuisse Faculty, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland; (M.L.M.); (H.L.); (B.R.); (R.H.-L.)
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10
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Westman M, Yang D, Green J, Norris J, Malik R, Parr YA, McDonald M, Hosie MJ, VandeWoude S, Miller C. Antibody Responses in Cats Following Primary and Annual Vaccination against Feline Immunodeficiency Virus (FIV) with an Inactivated Whole-Virus Vaccine (Fel-O-Vax ® FIV). Viruses 2021; 13:v13030470. [PMID: 33809232 PMCID: PMC7998844 DOI: 10.3390/v13030470] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/06/2021] [Accepted: 03/09/2021] [Indexed: 11/17/2022] Open
Abstract
Although the antibody response induced by primary vaccination with Fel-O-Vax® FIV (three doses, 2–4 weeks apart) is well described, the antibody response induced by annual vaccination with Fel-O-Vax® FIV (single dose every 12 months after primary vaccination) and how it compares to the primary antibody response has not been studied. Residual blood samples from a primary FIV vaccination study (n = 11), and blood samples from cats given an annual FIV vaccination (n = 10), were utilized. Samples from all 21 cats were tested with a commercially available PCR assay (FIV RealPCRTM), an anti-p24 microsphere immunoassay (MIA), an anti-FIV transmembrane (TM; gp40) peptide ELISA, and a range of commercially available point-of-care (PoC) FIV antibody kits. PCR testing confirmed all 21 cats to be FIV-uninfected for the duration of this study. Results from MIA and ELISA testing showed that both vaccination regimes induced significant antibody responses against p24 and gp40, and both anti-p24 and anti-gp40 antibodies were variably present 12 months after FIV vaccination. The magnitude of the antibody response against both p24 and gp40 was significantly higher in the primary FIV vaccination group than in the annual FIV vaccination group. The differences in prime versus recall post-vaccinal antibody levels correlated with FIV PoC kit performance. Two FIV PoC kits that detect antibodies against gp40, namely Witness® and Anigen Rapid®, showed 100% specificity in cats recently administered an annual FIV vaccination, demonstrating that they can be used to accurately distinguish vaccination and infection in annually vaccinated cats. A third FIV PoC kit, SNAP® Combo, had 0% specificity in annually FIV-vaccinated cats, and should not be used in any cat with a possible history of FIV vaccination. This study outlines the antibody response to inactivated Fel-O-Vax® FIV whole-virus vaccine, and demonstrates how best to diagnose FIV infection in jurisdictions where FIV vaccination is practiced.
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Affiliation(s)
- Mark Westman
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW 2006, Australia; (D.Y.); (J.G.); (J.N.)
- Correspondence:
| | - Dennis Yang
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW 2006, Australia; (D.Y.); (J.G.); (J.N.)
| | - Jennifer Green
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW 2006, Australia; (D.Y.); (J.G.); (J.N.)
| | - Jacqueline Norris
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW 2006, Australia; (D.Y.); (J.G.); (J.N.)
| | - Richard Malik
- Centre for Veterinary Education, The University of Sydney, Sydney, NSW 2006, Australia;
| | - Yasmin A. Parr
- MRC, University of Glasgow Centre for Virus Research, The University of Glasgow, Glasgow G61 1QH, UK; (Y.A.P.); (M.J.H.)
| | - Mike McDonald
- Veterinary Diagnostic Services, The University of Glasgow, Glasgow G61 1QH, UK;
| | - Margaret J. Hosie
- MRC, University of Glasgow Centre for Virus Research, The University of Glasgow, Glasgow G61 1QH, UK; (Y.A.P.); (M.J.H.)
| | - Sue VandeWoude
- 1619 Campus Delivery, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA;
| | - Craig Miller
- College of Veterinary Medicine, Oklahoma State University, 250 McElroy Hall, Stillwater, OK 74078, USA;
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11
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Parr YA, Beall MJ, Levy JK, McDonald M, Hamman NT, Willett BJ, Hosie MJ. Measuring the Humoral Immune Response in Cats Exposed to Feline Leukaemia Virus. Viruses 2021; 13:v13030428. [PMID: 33800090 PMCID: PMC7998633 DOI: 10.3390/v13030428] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/23/2021] [Accepted: 03/05/2021] [Indexed: 01/18/2023] Open
Abstract
Retroviruses belong to an important and diverse family of RNA viruses capable of causing neoplastic disease in their hosts. Feline leukaemia virus (FeLV) is a gammaretrovirus that infects domestic and wild cats, causing immunodeficiency, cytopenia and neoplasia in progressively infected cats. The outcome of FeLV infection is influenced by the host immune response; progressively infected cats demonstrate weaker immune responses compared to regressively infected cats. In this study, humoral immune responses were examined in 180 samples collected from 123 domestic cats that had been naturally exposed to FeLV, using a novel ELISA to measure antibodies recognizing the FeLV surface unit (SU) glycoprotein in plasma samples. A correlation was demonstrated between the strength of the humoral immune response to the SU protein and the outcome of exposure. Cats with regressive infection demonstrated higher antibody responses to the SU protein compared to cats belonging to other outcome groups, and samples from cats with regressive infection contained virus neutralising antibodies. These results demonstrate that an ELISA that assesses the humoral response to FeLV SU complements the use of viral diagnostic tests to define the outcome of exposure to FeLV. Together these tests could allow the rapid identification of regressively infected cats that are unlikely to develop FeLV-related disease.
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Affiliation(s)
- Yasmin A. Parr
- MRC—University of Glasgow Centre for Virus Research, Glasgow, Scotland G61 1QH, UK; (B.J.W.); (M.J.H.)
- Correspondence: ; Tel.: +44-0-141-330-3444
| | | | - Julie K. Levy
- Maddie’s Shelter Medicine Program, University of Florida, Gainesville, FL 32608, USA;
| | - Michael McDonald
- Veterinary Diagnostic Services, University of Glasgow, Glasgow, Scotland G61 1QH, UK;
| | | | - Brian J. Willett
- MRC—University of Glasgow Centre for Virus Research, Glasgow, Scotland G61 1QH, UK; (B.J.W.); (M.J.H.)
| | - Margaret J. Hosie
- MRC—University of Glasgow Centre for Virus Research, Glasgow, Scotland G61 1QH, UK; (B.J.W.); (M.J.H.)
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12
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Anti-SU Antibody Responses in Client-Owned Cats Following Vaccination against Feline Leukaemia Virus with Two Inactivated Whole-Virus Vaccines (Fel-O-Vax ® Lv-K and Fel-O-Vax ® 5). Viruses 2021; 13:v13020240. [PMID: 33546485 PMCID: PMC7913631 DOI: 10.3390/v13020240] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/29/2021] [Accepted: 02/02/2021] [Indexed: 12/16/2022] Open
Abstract
A field study undertaken in Australia compared the antibody responses induced in client-owned cats that had been vaccinated using two inactivated whole feline leukaemia virus (FeLV) vaccines, the monovalent vaccine Fel-O-Vax® Lv-K and the polyvalent vaccine Fel-O-Vax® 5. Serum samples from 428 FeLV-uninfected cats (118 FeLV-vaccinated and 310 FeLV-unvaccinated) were tested for anti-FeLV neutralising antibodies (NAb) using a live virus neutralisation assay to identify 378 FeLV-unexposed (NAb-negative) and 50 FeLV-exposed (NAb-positive; abortive infections) cats, following by anti-surface unit (SU) FeLV-A and FeLV-B antibody ELISA testing. An additional 42 FeLV-infected cats (28 presumptively regressively infected, 14 presumptively progressively infected) were also tested for anti-SU antibodies. NAb-positive cats displayed significantly higher anti-SU antibody ELISA responses compared to NAb-negative cats (p < 0.001). FeLV-unexposed cats (NAb-negative) that had been vaccinated less than 18 months after a previous FeLV vaccination using the monovalent vaccine (Fel-O-Vax® Lv-K) displayed higher anti-SU antibody ELISA responses than a comparable group vaccinated with the polyvalent vaccine (Fel-O-Vax® 5) (p < 0.001 for both anti-FeLV-A and FeLV-B SU antibody responses). This difference in anti-SU antibody responses between cats vaccinated with the monovalent or polyvalent vaccine, however, was not observed in cats that had been naturally exposed to FeLV (NAb-positive) (p = 0.33). It was postulated that vaccination with Fel-O-Vax® 5 primed the humoral response prior to FeLV exposure, such that antibody production increased when the animal was challenged, while vaccination with Fel-O-Vax® Lv-K induced an immediate preparatory antibody response that did not quantitatively increase after FeLV exposure. These results raise questions about the comparable vaccine efficacy of the different FeLV vaccine formulations and correlates of protection.
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13
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Stone AES, Brummet GO, Carozza EM, Kass PH, Petersen EP, Sykes J, Westman ME. 2020 AAHA/AAFP Feline Vaccination Guidelines. J Feline Med Surg 2020; 22:813-830. [PMID: 32845224 PMCID: PMC11135662 DOI: 10.1177/1098612x20941784] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
The guidelines are a consensus report on current recommendations for vaccination of cats of any origin, authored by a Task Force of experts. The guidelines are published simultaneously in the Journal of Feline Medicine and Surgery (volume 22, issue 9, pages 813-830, DOI: 10.1177/1098612X20941784) and the Journal of the American Animal Hospital Association (volume 56, issue 4, pages 249-265, DOI: 10.5326/JAAHA-MS-7123). The guidelines assign approved feline vaccines to core (recommended for all cats) and non-core (recommended based on an individualized risk-benefit assessment) categories. Practitioners can develop individualized vaccination protocols consisting of core vaccines and non-core vaccines based on exposure and susceptibility risk as defined by the patient's life stage, lifestyle, and place of origin and by environmental and epidemiologic factors. An update on feline injection-site sarcomas indicates that occurrence of this sequela remains infrequent and idiosyncratic. Staff education initiatives should enable the veterinary practice team to be proficient in advising clients on proper vaccination practices and compliance. Vaccination is a component of a preventive healthcare plan. The vaccination visit should always include a thorough physical exam and client education dialog that gives the pet owner an understanding of how clinical staff assess disease risk and propose recommendations that help ensure an enduring owner-pet relationship.
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Affiliation(s)
- Amy ES Stone
- Chair of 2020 AAHA/AAFP Feline Vaccination
Guidelines Task Force
- Department of Small Animal Clinical Sciences,
University of Florida, Gainesville, Florida, USA
| | - Gary O Brummet
- DVM Veterinary Teaching Hospital, College of
Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana,
Illinois, USA
| | | | - Philip H Kass
- DVM, MPVM, MS, PhD, DACVPM (Specialty in
Epidemiology) Department of Population Health and Reproduction, School of
Veterinary Medicine, University of California, Davis, Davis, California,
USA
| | - Ernest P Petersen
- DVM, PhD, DABVP (Feline) Animal Hospital of
Parkland, Tacoma, Washington, USA
| | - Jane Sykes
- BVSc (Hons), PhD, DACVIM, MBA University of
California, Davis, Davis, California, USA
| | - Mark E Westman
- BVSc (Hons), PhD, MANZCVS (Animal Welfare),
GradCert Ed Stud (Higher Ed)) Sydney School of Veterinary Science,
University of Sydney, Sydney, New South Wales, Australia
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14
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Abstract
PRACTICAL RELEVANCE Feline leukaemia virus (FeLV) is a retrovirus of domestic cats worldwide. Cats lacking strong FeLV-specific immunity and undergoing progressive infection commonly develop fatal FeLV-associated disease. Many aspects of FeLV infection pathogenesis have been elucidated, some during more recent years using molecular techniques. It is recommended that the FeLV status of every cat is known, since FeLV infection can influence the prognosis and clinical management of every sick cat. Moreover, knowledge of a cat's FeLV status is of epidemiological importance to prevent further spread of the infection. CLINICAL CHALLENGES Diagnosing FeLV infection remains challenging due to different outcomes of infection, which can vary over time depending on the balance between the virus and the host's immune system. Furthermore, testing for FeLV infection has become more refined over the years and now includes diagnostic assays for different viral and immunological parameters. Knowledge of FeLV infection pathogenesis, as well as the particulars of FeLV detection methods, is an important prerequisite for correct interpretation of any test results and accurate determination of a cat's FeLV status. AIMS The current review presents recent knowledge on FeLV pathogenesis, key features to be determined in FeLV infection, and frequently used FeLV detection methods, and their characteristics and interpretation. An algorithm for the diagnosis of FeLV infection in a single cat, developed by the European Advisory Board on Cat Diseases, is included, and FeLV testing in specific situations is addressed. As well as increasing awareness of this deadly infection in domestic cats, the aim is to contribute diagnostic expertise to allow veterinarians in practice to improve their recognition, and further reduce the prevalence, of FeLV infection.
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Affiliation(s)
- Regina Hofmann-Lehmann
- Prof, Dr med vet, FVH Professor of Laboratory Medicine, Director of Department of Clinical Diagnostics and Services, Head of Clinical Laboratory and Centre for Clinical Studies, Vetsuisse Faculty, University of Zurich, Switzerland
| | - Katrin Hartmann
- Prof, Dr med vet, Dr habil, Dip ECVIM-CA (Internal Medicine) Professor of Internal Medicine, Head of Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, LMU Munich, Germany
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15
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Stone AES, Brummet GO, Carozza EM, Kass PH, Petersen EP, Sykes J, Westman ME. 2020 AAHA/AAFP Feline Vaccination Guidelines*. J Am Anim Hosp Assoc 2020. [DOI: 10.5326/jaaha-ms-7123] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
ABSTRACT
The guidelines are a consensus report on current recommendations for vaccination of cats of any origin, authored by a Task Force of experts. The guidelines are published simultaneously in the Journal of Feline Medicine and Surgery (volume 22, issue 9, pages 813–830, DOI: 10.1177/1098612X20941784) and the Journal of the American Animal Hospital Association (volume 56, issue 4, pages 249–265, DOI: 10.5326/JAAHA-MS-7123). The guidelines assign approved feline vaccines to core (recommended for all cats) and non-core (recommended based on an individualized risk-benefit assessment) categories. Practitioners can develop individualized vaccination protocols consisting of core vaccines and non-core vaccines based on exposure and susceptibility risk as defined by the patient’s life stage, lifestyle, and place of origin and by environmental and epidemiologic factors. An update on feline injection-site sarcomas indicates that occurrence of this sequela remains infrequent and idiosyncratic. Staff education initiatives should enable the veterinary practice team to be proficient in advising clients on proper vaccination practices and compliance. Vaccination is a component of a preventive healthcare plan. The vaccination visit should always include a thorough physical exam and client education dialog that gives the pet owner an understanding of how clinical staff assess disease risk and propose recommendations that help ensure an enduring owner-pet relationship.
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Affiliation(s)
- Amy E. S. Stone
- From the Department of Small Animal Clinical Sciences, University of Florida, Gainesville, Florida, USA (A.E.S.S.); Veterinary Teaching Hospital, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA (G.O.B.); Nova Cat Clinic, Arlington, Virginia, USA (E.M.C.); Department of Population Health and Reproduction, School of Veterinary Medicine, University o
| | - Gary O. Brummet
- From the Department of Small Animal Clinical Sciences, University of Florida, Gainesville, Florida, USA (A.E.S.S.); Veterinary Teaching Hospital, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA (G.O.B.); Nova Cat Clinic, Arlington, Virginia, USA (E.M.C.); Department of Population Health and Reproduction, School of Veterinary Medicine, University o
| | - Ellen M. Carozza
- From the Department of Small Animal Clinical Sciences, University of Florida, Gainesville, Florida, USA (A.E.S.S.); Veterinary Teaching Hospital, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA (G.O.B.); Nova Cat Clinic, Arlington, Virginia, USA (E.M.C.); Department of Population Health and Reproduction, School of Veterinary Medicine, University o
| | - Philip H. Kass
- From the Department of Small Animal Clinical Sciences, University of Florida, Gainesville, Florida, USA (A.E.S.S.); Veterinary Teaching Hospital, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA (G.O.B.); Nova Cat Clinic, Arlington, Virginia, USA (E.M.C.); Department of Population Health and Reproduction, School of Veterinary Medicine, University o
| | - Ernest P. Petersen
- From the Department of Small Animal Clinical Sciences, University of Florida, Gainesville, Florida, USA (A.E.S.S.); Veterinary Teaching Hospital, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA (G.O.B.); Nova Cat Clinic, Arlington, Virginia, USA (E.M.C.); Department of Population Health and Reproduction, School of Veterinary Medicine, University o
| | - Jane Sykes
- From the Department of Small Animal Clinical Sciences, University of Florida, Gainesville, Florida, USA (A.E.S.S.); Veterinary Teaching Hospital, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA (G.O.B.); Nova Cat Clinic, Arlington, Virginia, USA (E.M.C.); Department of Population Health and Reproduction, School of Veterinary Medicine, University o
| | - Mark E. Westman
- From the Department of Small Animal Clinical Sciences, University of Florida, Gainesville, Florida, USA (A.E.S.S.); Veterinary Teaching Hospital, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA (G.O.B.); Nova Cat Clinic, Arlington, Virginia, USA (E.M.C.); Department of Population Health and Reproduction, School of Veterinary Medicine, University o
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16
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Hartmann K, Hofmann-Lehmann R. What's New in Feline Leukemia Virus Infection. Vet Clin North Am Small Anim Pract 2020; 50:1013-1036. [PMID: 32680664 DOI: 10.1016/j.cvsm.2020.05.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Feline leukemia virus (FeLV) is a retrovirus with global impact on the health of domestic cats that causes tumors (mainly lymphoma), bone marrow disorders, and immunosuppression. The importance of FeLV is underestimated due to complacency associated with previous decline in prevalence. However, with this comes lowered vigilance, which, along with potential for regressively infected cats to reactivate viremia and shed the virus or develop clinical signs, can pose a risk to feline health. This article summarizes knowledge on FeLV pathogenesis, courses of infection, and factors affecting prevalance, infection outcome, and development of FeLV-associated diseases, with special focus on regressive FeLV infection.
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Affiliation(s)
- Katrin Hartmann
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine LMU Munich, Veterinaerstrasse 13, Munich 80539, Germany.
| | - Regina Hofmann-Lehmann
- Clinical Laboratory, Department for Clinical Diagnostics and Services, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, Zurich 8057, Switzerland
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17
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Little S, Levy J, Hartmann K, Hofmann-Lehmann R, Hosie M, Olah G, Denis KS. 2020 AAFP Feline Retrovirus Testing and Management Guidelines. J Feline Med Surg 2020; 22:5-30. [PMID: 31916872 PMCID: PMC11135720 DOI: 10.1177/1098612x19895940] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
CLINICAL IMPORTANCE Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) infections are found in cats worldwide. Both infections are associated with a variety of clinical signs and can impact quality of life and longevity. SCOPE This document is an update of the 2008 American Association of Feline Practitioners' feline retrovirus management guidelines and represents current knowledge on pathogenesis, diagnosis, prevention and treatment of retrovirus infections in cats. TESTING AND INTERPRETATION Although vaccines are available for FeLV in many countries and for FIV in some countries, identification of infected cats remains an important factor for preventing new infections. The retrovirus status of every cat at risk of infection should be known. Cats should be tested as soon as possible after they are acquired, following exposure to an infected cat or a cat of unknown infection status, prior to vaccination against FeLV or FIV, and whenever clinical illness occurs. It might not be possible to determine a cat's infection status based on testing at a single point in time; repeat testing using different methods could be required. Although FeLV and FIV infections can be associated with clinical disease, some infected cats, especially those infected with FIV, can live for many years with good quality of life. MANAGEMENT OF INFECTED CATS There is a paucity of data evaluating treatments for infected cats, especially antiretroviral and immunomodulatory drugs. Management of infected cats is focused on effective preventive healthcare strategies, and prompt identification and treatment of illness, as well as limiting the spread of infection.
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Affiliation(s)
| | - Julie Levy
- Charing Cross Cat Clinic, Brantford, ON, Canada
| | | | | | | | - Glenn Olah
- Charing Cross Cat Clinic, Brantford, ON, Canada
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18
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Abdollahi-Pirbazari M, Jamshidi S, Nassiri SM, Zamani-Ahmadmahmudi M. Comparative measurement of FeLV load in hemolymphatic tissues of cats with hematologic cytopenias. BMC Vet Res 2019; 15:460. [PMID: 31856815 PMCID: PMC6924046 DOI: 10.1186/s12917-019-2208-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Accepted: 12/04/2019] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Feline leukemia virus (FeLV) is a serious viral infection in cats. FeLV is found in some tissues, such as spleen, lymph nodes and epithelial tissues. However, there is controversy about the organ in which the virus can be reliably detected in infected cats. The purpose of this study was to determine the level of viral infection in hemolymphatic tissues, including blood, bone marrow and spleen by reverse-transcriptase quantitative polymerase chain reaction (RT-qPCR). RESULTS A total of 31 cats with clinical signs of FeLV infection associated with at least a single lineage hematologic cytopenia were included in this study. Peripheral blood, bone marrow and spleen samples were obtained from each cat. Complete blood counts, biochemical tests, and a rapid test to detect FeLV p27 antigen in blood samples of cats were performed. Of 31 cats, 9 had anemia alone, 4 had thrombocytopenia alone, 2 had neutropenia alone, 9 had bicytopenia of anemia and thrombocytopenia, 3 had bicytopenia of anemia and neutropenia, and 4 had pancytopenia. FeLV RNA was then detected by RT-qPCR in the whole blood, bone marrow and spleen. Viral RNA copy numbers were detected in all cats by RT-qPCR whereas 24 out of 31 cats were positive for the serum FeLV antigen. We detected a significantly greater number of viral RNA in the spleen compared with the whole blood and bone marrow. CONCLUSION Spleen is a site where FeLV is most frequently detected in cats with hematologic cytopenias.
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Affiliation(s)
| | - Shahram Jamshidi
- Department of Internal Medicine, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
| | - Seyed Mahdi Nassiri
- Department of Clinical Pathology, Faculty of Veterinary Medicine, University of Tehran, Qareeb St., Azadi Ave, Tehran, Iran.
| | - Mohamad Zamani-Ahmadmahmudi
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahid Bahonar University of Kerman, Kerman, Iran
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19
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Westman M, Norris J, Malik R, Hofmann-Lehmann R, Harvey A, McLuckie A, Perkins M, Schofield D, Marcus A, McDonald M, Ward M, Hall E, Sheehy P, Hosie M. The Diagnosis of Feline Leukaemia Virus (FeLV) Infection in Owned and Group-Housed Rescue Cats in Australia. Viruses 2019; 11:v11060503. [PMID: 31159230 PMCID: PMC6630418 DOI: 10.3390/v11060503] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 05/21/2019] [Accepted: 05/29/2019] [Indexed: 12/11/2022] Open
Abstract
A field study was undertaken to (i) measure the prevalence of feline leukaemia virus (FeLV) exposure and FeLV infection in a cross-section of healthy Australian pet cats; and (ii) investigate the outcomes following natural FeLV exposure in two Australian rescue facilities. Group 1 (n = 440) consisted of healthy client-owned cats with outdoor access, predominantly from eastern Australia. Groups 2 (n = 38) and 3 (n = 51) consisted of a mixture of healthy and sick cats, group-housed in two separate rescue facilities in Sydney, Australia, tested following identification of index cases of FeLV infection in cats sourced from these facilities. Diagnostic testing for FeLV exposure/infection included p27 antigen testing using three different point-of-care FeLV kits and a laboratory-based ELISA, real-time polymerase chain reaction (qPCR) testing to detect FeLV proviral DNA in leukocytes, real-time reverse-transcription PCR (qRT-PCR) testing to detect FeLV RNA in plasma, and neutralising antibody (NAb) testing. Cats were classified as FeLV-uninfected (FeLV-unexposed and presumptively FeLV-abortive infections) or FeLV-infected (presumptively regressive and presumptively progressive infections). In Group 1, 370 FeLV-unexposed cats (370/440, 84%), 47 abortive infections (47/440, 11%), nine regressive infections (9/440, 2%), and two progressive infections (2/440, 0.5%) were identified, and 12 FeLV-uninfected cats (12/440, 3%) were unclassifiable as FeLV-unexposed or abortive infections due to insufficient samples available for NAb testing. In Groups 2 and 3, 31 FeLV-unexposed cats (31/89, 35%), eight abortive infections (8/89, 9%), 22 regressive infections (22/89; 25%), and 19 progressive infections (19/89; 21%) were discovered, and nine FeLV-uninfected cats (9/89; 10%) were unclassifiable due to insufficient samples available for NAb testing. One of the presumptively progressively-infected cats in Group 3 was likely a focal FeLV infection. Two other presumptively progressively-infected cats in Group 3 may have been classified as regressive infections with repeated testing, highlighting the difficulties associated with FeLV diagnosis when sampling cats at a single time point, even with results from a panel of FeLV tests. These results serve as a reminder to Australian veterinarians that the threat of FeLV to the general pet cat population remains high, thus vigilant FeLV testing, separate housing for FeLV-infected cats, and FeLV vaccination of at-risk cats is important, particularly in group-housed cats in shelters and rescue facilities, where outbreaks of FeLV infection can occur.
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Affiliation(s)
- Mark Westman
- Sydney School of Veterinary Science, The University of Sydney, Camperdown, 2006 NSW, Australia.
| | - Jacqueline Norris
- Sydney School of Veterinary Science, The University of Sydney, Camperdown, 2006 NSW, Australia.
| | - Richard Malik
- Centre for Veterinary Education, The University of Sydney, Camperdown, 2006 NSW, Australia.
| | - Regina Hofmann-Lehmann
- Clinical Laboratory and Centre for Clinical Studies, Vetsuisse Faculty, The University of Zurich, CH-8057 Zürich, Switzerland.
| | - Andrea Harvey
- Small Animal Specialist Hospital, 1 Richardson Place, North Ryde, Sydney, 2113 NSW, Australia.
| | - Alicia McLuckie
- Sydney School of Veterinary Science, The University of Sydney, Camperdown, 2006 NSW, Australia.
| | | | | | - Alan Marcus
- Sydney School of Veterinary Science, The University of Sydney, Camperdown, 2006 NSW, Australia.
| | - Mike McDonald
- Veterinary Diagnostic Services, The University of Glasgow, Glasgow, Scotland G61 1QH, UK.
| | - Michael Ward
- Sydney School of Veterinary Science, The University of Sydney, Camden, 2570 NSW, Australia.
| | - Evelyn Hall
- Sydney School of Veterinary Science, The University of Sydney, Camden, 2570 NSW, Australia.
| | - Paul Sheehy
- Sydney School of Veterinary Science, The University of Sydney, Camden, 2570 NSW, Australia.
| | - Margaret Hosie
- MRC-University of Glasgow Centre for Virus Research, Glasgow, Scotland G61 1QH, UK.
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20
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Westman ME, Malik R, Norris JM. Diagnosing feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV) infection: an update for clinicians. Aust Vet J 2019; 97:47-55. [DOI: 10.1111/avj.12781] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 10/20/2018] [Accepted: 10/23/2018] [Indexed: 11/29/2022]
Affiliation(s)
- ME Westman
- Sydney School of Veterinary Science; The University of Sydney; NSW Australia
| | - R Malik
- Centre for Veterinary Education; The University of Sydney; NSW Australia
| | - JM Norris
- Sydney School of Veterinary Science; The University of Sydney; NSW Australia
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21
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Filoni C, Helfer-Hungerbuehler AK, Catão-Dias JL, Marques MC, Torres LN, Reinacher M, Hofmann-Lehmann R. Putative progressive and abortive feline leukemia virus infection outcomes in captive jaguarundis (Puma yagouaroundi). Virol J 2017; 14:226. [PMID: 29149857 PMCID: PMC5693524 DOI: 10.1186/s12985-017-0889-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 11/02/2017] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Feline leukemia virus (FeLV) is an exogenous gammaretrovirus of domestic cats (Felis catus) and some wild felids. The outcomes of FeLV infection in domestic cats vary according to host susceptibility, virus strain, and infectious challenge dose. Jaguarundis (Puma yagouaroundi) are small wild felids from South and Central America. We previously reported on FeLV infections in jaguarundis. We hypothesized here that the outcomes of FeLV infection in P. yagouaroundi mimic those observed in domestic cats. The aim of this study was to investigate the population of jaguarundis at Fundação Parque Zoológico de São Paulo for natural FeLV infection and resulting outcomes. METHODS We investigated the jaguarundis using serological and molecular methods and monitored them for FeLV-related diseases for 5 years. We retrieved relevant biological and clinical information for the entire population of 23 jaguarundis held at zoo. Post-mortem findings from necropsies were recorded and histopathological and immunohistopathological analyses were performed. Sequencing and phylogenetic analyses were performed for FeLV-positive samples. For sample prevalence, 95% confidence intervals (CI) were calculated. Fisher's exact test was used to compare frequencies between infected and uninfected animals. P-values <0.05 were considered significant. RESULTS In total, we detected evidence of FeLV exposure in four out of 23 animals (17%; 95% CI 5-39%). No endogenous FeLV (enFeLV) sequences were detected. An intestinal B-cell lymphoma in one jaguarundi was not associated with FeLV. Two jaguarundis presented FeLV test results consistent with an abortive FeLV infection with seroconversion, and two other jaguarundis had results consistent with a progressive infection and potentially FeLV-associated clinical disorders and post-mortem changes. Phylogenetic analysis of env revealed the presence of FeLV-A, a common origin of the virus in both animals (100% identity) and the closest similarity to FeLV-FAIDS and FeLV-3281 (98.4% identity), originally isolated from cats in the USA. CONCLUSIONS We found evidence of progressive and abortive FeLV infection outcomes in jaguarundis, and domestic cats were probably the source of infection in these jaguarundis.
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Affiliation(s)
- Claudia Filoni
- Institute of Biosciences, Department of Microbiology and Immunology, São Paulo State University (UNESP), Campus Botucatu, Rua Professor Doutor Antonio Celso Wagner Zanin SN, Botucatu, São Paulo, 18618-689, Brazil.
| | - A Katrin Helfer-Hungerbuehler
- Vetsuisse Faculty, Clinical Laboratory and Center for Clinical Studies, University of Zurich, Winterthurerstrasse 260, 8057, Zurich, Switzerland
| | - José Luiz Catão-Dias
- School of Veterinary Medicine and Animal Sciences, Department of Pathology, University of São Paulo (USP), Av. Prof. Orlando Marques de Paiva 87, São Paulo, 05508-270, São Paulo, Brazil
| | - Mara Cristina Marques
- Fundação Parque Zoológico de São Paulo (FPZSP), Av. Miguel Stéfano 4241, São Paulo, São Paulo, 04301-905, Brazil
| | - Luciana Neves Torres
- School of Veterinary Medicine and Animal Sciences, Veterinary Hospital (HOVET), University of São Paulo (USP), Av. Prof. Orlando Marques de Paiva 87, São Paulo, 05508-270, São Paulo, Brazil
| | - Manfred Reinacher
- Institute of Veterinary Pathology, University of Giessen, Frankfurter Strasse 96, Giessen, 35392, Germany
| | - Regina Hofmann-Lehmann
- Vetsuisse Faculty, Clinical Laboratory and Center for Clinical Studies, University of Zurich, Winterthurerstrasse 260, 8057, Zurich, Switzerland
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22
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Möstl K, Addie DD, Boucraut-Baralon C, Egberink H, Frymus T, Gruffydd-Jones T, Hartmann K, Hosie MJ, Lloret A, Lutz H, Marsilio F, Pennisi MG, Radford AD, Thiry E, Truyen U, Horzinek MC. Something old, something new: Update of the 2009 and 2013 ABCD guidelines on prevention and management of feline infectious diseases. J Feline Med Surg 2015; 17:570-82. [PMID: 26101308 DOI: 10.1177/1098612x15588448] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OVERVIEW The ABCD has published 34 guidelines in two Special Issues of the Journal of Feline Medicine and Surgery (JFMS): the first in July 2009 (Volume 11, Issue 7, pages 527-620) and the second in July 2013 (Volume 15, Issue 7, pages 528-652). The present article contains updates and new information on 18 of these (17 disease guidelines and one special article 'Prevention of infectious diseases in cat shelters'). For detailed information, readers are referred to the guidelines published in the above-mentioned JFMS Special Issues.
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23
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Nesina S, Katrin Helfer-Hungerbuehler A, Riond B, Boretti FS, Willi B, Meli ML, Grest P, Hofmann-Lehmann R. Retroviral DNA--the silent winner: blood transfusion containing latent feline leukemia provirus causes infection and disease in naïve recipient cats. Retrovirology 2015; 12:105. [PMID: 26689419 PMCID: PMC4687292 DOI: 10.1186/s12977-015-0231-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 12/09/2015] [Indexed: 11/23/2022] Open
Abstract
Background
The feline leukemia virus (FeLV) is a gamma-retrovirus of domestic cats that was discovered half a century ago. Cats that are infected with FeLV may develop a progressive infection resulting in persistent viremia, immunodeficiency, tumors, anemia and death. A significant number of cats mount a protective immune response that suppresses viremia; these cats develop a regressive infection characterized by the absence of viral replication and the presence of low levels of proviral DNA. The biological importance of these latter provirus carriers is largely unknown. Results Here, we demonstrate that ten cats that received a transfusion of blood from aviremic provirus carriers developed active FeLV infections, some with a progressive outcome and the development of fatal FeLV-associated disease. The infection outcome, disease spectrum and evolution into FeLV-C in one cat mirrored those of natural infection. Two cats developed persistent antigenemia; six cats were transiently antigenemic. Reactivation of infection occurred in some cats. One recipient developed non-regenerative anemia associated with FeLV-C, and four others developed a T-cell lymphoma, one with secondary lymphoblastic leukemia. Five of the ten recipient cats received provirus-positive aviremic blood, whereas the other five received provirus- and viral RNA-positive but aviremic blood. Notably, the cats that received blood containing only proviral DNA exhibited a later onset but graver outcome of FeLV infection than the cats that were transfused with blood containing proviral DNA and viral RNA. Leukocyte counts and cytokine analyses indicated that the immune system of the latter cats reacted quicker and more efficiently. Conclusions Our results underline the biological and epidemiological relevance of FeLV provirus carriers and the risk of inadvertent FeLV transmission via blood transfusion and demonstrate the replication capacity of proviral DNA if uncontrolled by the immune system. Our results have implications not only for veterinary medicine, such as the requirement for testing blood donors and blood products for FeLV provirus by sensitive polymerase chain reaction, but are also of general interest by revealing the importance of latent retroviral DNA in infected hosts. When aiming to eliminate a retroviral infection from a population, provirus carriers must be considered. Electronic supplementary material The online version of this article (doi:10.1186/s12977-015-0231-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Stefanie Nesina
- Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. .,Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
| | - A Katrin Helfer-Hungerbuehler
- Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. .,Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
| | - Barbara Riond
- Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
| | - Felicitas S Boretti
- Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
| | - Barbara Willi
- Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. .,Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
| | - Marina L Meli
- Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. .,Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
| | - Paula Grest
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
| | - Regina Hofmann-Lehmann
- Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland. .,Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
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24
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No benefit of therapeutic vaccination in clinically healthy cats persistently infected with feline leukemia virus. Vaccine 2015; 33:1578-85. [PMID: 25698488 DOI: 10.1016/j.vaccine.2015.02.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Accepted: 02/04/2015] [Indexed: 11/22/2022]
Abstract
Therapeutic vaccinations have a potential application in infections where no curative treatment is available. In contrast to HIV, efficacious vaccines for a cat retrovirus, feline leukemia virus (FeLV), are commercially available. However, the infection is still prevalent, and no effective treatment of the infection is known. By vaccinating persistently FeLV-infected cats and presenting FeLV antigens to the immune system of the host, e.g., in the form of recombinant and/or adjuvanted antigens, we intended to shift the balance toward an advantage of the host so that persistent infection could be overcome by the infected cat. Two commercially available FeLV vaccines efficacious in protecting naïve cats from FeLV infection were tested in six experimentally and persistently FeLV-infected cats: first, a canarypox-vectored vaccine, and second, an adjuvanted, recombinant envelope vaccine was repeatedly administered with the aim to stimulate the immune system. No beneficial effects on p27 antigen and plasma viral RNA loads, anti-FeLV antibodies, or life expectancy of the cats were detected. The cats were unable to overcome or decrease viremia. Some cats developed antibodies to FeLV antigens although not protective. Thus, we cannot recommend vaccinating persistently FeLV-infected cats as a means of improving their FeLV status, quality of life or life expectancy. We suggest testing of all cats for FeLV infection prior to FeLV vaccination.
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