{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T01:30:33Z","timestamp":1792027833377,"version":"4.4.0"},"reference-count":51,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2020,7,22]],"date-time":"2020-07-22T00:00:00Z","timestamp":1595376000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Background: Feline coronavirus (FCoV) infection is ubiquitous in multi-cat households. Responsible for the continuous presence are cats that are chronically shedding a high load of FCoV. The aim of the study was to determine a possible correlation between FCoV antibody titer and frequency and load of fecal FCoV shedding in cats from catteries. Methods: Four fecal samples from each of 82 cats originating from 19 German catteries were examined for FCoV viral loads by quantitative reverse transcriptase polymerase chain reaction (RT-qPCR). Additionally, antibody titers were determined by an immunofluorescence assay. Results: Cats with antibodies were more likely to be FCoV shedders than non-shedders, and there was a weak positive correlation between antibody titer and mean fecal virus load (Spearman r = 0.2984; p = 0.0072). Antibody titers were significantly higher if cats shed FCoV more frequently throughout the study period (p = 0.0063). When analyzing only FCoV shedders, cats that were RT-qPCR-positive in all four samples had significantly higher antibody titers (p = 0.0014) and significantly higher mean fecal virus loads (p = 0.0475) than cats that were RT-qPCR-positive in only one, two, or three samples. Conclusions: The cats\u2019 antibody titers correlate with the likelihood and frequency of FCoV shedding and fecal virus load. Chronic shedders have higher antibody titers and shed more virus. This knowledge is important for the management of FCoV infections in multi-cat environments, but the results indicate that antibody measurement cannot replace fecal RT-qPCR.<\/jats:p>","DOI":"10.3390\/pathogens9080598","type":"journal-article","created":{"date-parts":[[2020,7,22]],"date-time":"2020-07-22T07:31:28Z","timestamp":1595403088000},"page":"598","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Correlation of Feline Coronavirus Shedding in Feces with Coronavirus Antibody Titer"],"prefix":"10.3390","volume":"9","author":[{"given":"Sandra","family":"Felten","sequence":"first","affiliation":[{"name":"Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, LMU Munich, Veterinaerstrasse 13, 80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ute","family":"Klein-Richers","sequence":"additional","affiliation":[{"name":"Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, LMU Munich, Veterinaerstrasse 13, 80539 Munich, Germany"}],"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, Vetsuisse Faculty, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mich\u00e8le","family":"Bergmann","sequence":"additional","affiliation":[{"name":"Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, LMU Munich, Veterinaerstrasse 13, 80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefan","family":"Unterer","sequence":"additional","affiliation":[{"name":"Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, LMU Munich, Veterinaerstrasse 13, 80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian M.","family":"Leutenegger","sequence":"additional","affiliation":[{"name":"IDEXX Laboratories, Inc., 2825 KOVR Dr., West Sacramento, CA 95605, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katrin","family":"Hartmann","sequence":"additional","affiliation":[{"name":"Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, LMU Munich, Veterinaerstrasse 13, 80539 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"419","DOI":"10.1136\/vr.146.15.419","article-title":"Long-term impact on a closed household of pet cats of natural infection with feline coronavirus, feline leukaemia virus and feline immunodeficiency virus","volume":"146","author":"Addie","year":"2000","journal-title":"Vet. Rec."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1313","DOI":"10.2460\/javma.1997.210.09.1313","article-title":"Risk factors for feline infectious peritonitis among cats in multiple-cat environments with endemic feline enteric coronavirus","volume":"210","author":"Foley","year":"1997","journal-title":"J. Am. Vet. Med. Assoc."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"529","DOI":"10.1016\/j.jfms.2008.02.006","article-title":"Pathogenesis of feline enteric coronavirus infection","volume":"10","author":"Pedersen","year":"2008","journal-title":"J. Feline Med. Surg."},{"key":"ref_4","unstructured":"Scott, F.W. (1988, January 16\u201317). Update on FIP. Proceedings of the 12th Annual Kal Kan Symposium for the Treatment of Small Animal Disease, Johnson, OH, USA."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1016\/j.jfms.2004.01.003","article-title":"Risk factors for feline coronavirus seropositivity in cats relinquished to a UK rescue charity","volume":"6","author":"Cave","year":"2004","journal-title":"J. Feline Med. Surg."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1053\/tvjl.1999.0429","article-title":"Clustering of feline coronaviruses in multicat households","volume":"159","author":"Addie","year":"2000","journal-title":"Vet. J."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1016\/j.jfms.2003.08.008","article-title":"Common virus infections in cats, before and after being placed in shelters, with emphasis on feline enteric coronavirus","volume":"6","author":"Pedersen","year":"2004","journal-title":"J. Feline Med. Surg."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"429","DOI":"10.2460\/ajvr.1995.56.04.429","article-title":"Risk of feline infectious peritonitis in cats naturally infected with feline coronavirus","volume":"56","author":"Addie","year":"1995","journal-title":"Am. J. Vet. Res."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"3180","DOI":"10.1128\/jcm.34.12.3180-3184.1996","article-title":"Two related strains of feline infectious peritonitis virus isolated from immunocompromised cats infected with a feline enteric coronavirus","volume":"34","author":"Poland","year":"1996","journal-title":"J. Clin. Microbiol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"150","DOI":"10.1006\/viro.1998.9045","article-title":"Feline infectious peritonitis viruses arise by mutation from endemic feline enteric coronaviruses","volume":"243","author":"Vennema","year":"1998","journal-title":"Virology"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1354\/vp.42-3-321","article-title":"Morphologic features and development of granulomatous vasculitis in feline infectious peritonitis","volume":"42","author":"Kipar","year":"2005","journal-title":"Vet. Pathol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1016\/j.vetimm.2006.02.004","article-title":"Natural feline coronavirus infection: Differences in cytokine patterns in association with the outcome of infection","volume":"112","author":"Kipar","year":"2006","journal-title":"Vet. Immunol. Immunopathol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"2633","DOI":"10.1099\/jgv.0.000585","article-title":"Upregulation of endothelial cell adhesion molecules characterizes veins close to granulomatous infiltrates in the renal cortex of cats with feline infectious peritonitis and is indirectly triggered by feline infectious peritonitis virus-infected monocytes in vitro","volume":"97","author":"Acar","year":"2016","journal-title":"J. Gen. Virol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"775","DOI":"10.1007\/s00705-009-0371-3","article-title":"Neutrophil survival factors (TNF-alpha, GM-CSF, and G-CSF) produced by macrophages in cats infected with feline infectious peritonitis virus contribute to the pathogenesis of granulomatous lesions","volume":"154","author":"Takano","year":"2009","journal-title":"Arch. Virol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1016\/j.vetmic.2006.08.033","article-title":"A \u201cpossible\u201d involvement of TNF-alpha in apoptosis induction in peripheral blood lymphocytes of cats with feline infectious peritonitis","volume":"119","author":"Takano","year":"2007","journal-title":"Vet. Microbiol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"64","DOI":"10.1016\/j.virol.2007.02.006","article-title":"TNF-alpha, produced by feline infectious peritonitis virus (FIPV)-infected macrophages, upregulates expression of type II FIPV receptor feline aminopeptidase N in feline macrophages","volume":"364","author":"Takano","year":"2007","journal-title":"Virology"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"522","DOI":"10.1136\/vr.139.21.522","article-title":"Feline coronavirus in the intestinal contents of cats with feline infectious peritonitis","volume":"139","author":"Addie","year":"1996","journal-title":"Vet. Rec."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1016\/j.jfms.2003.08.007","article-title":"High viral loads despite absence of clinical and pathological findings in cats experimentally infected with feline coronavirus (FCoV) type I and in naturally FCoV-infected cats","volume":"6","author":"Meli","year":"2004","journal-title":"J. Feline Med. Surg."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1186\/s13567-017-0467-9","article-title":"Limitations of using feline coronavirus spike protein gene mutations to diagnose feline infectious peritonitis","volume":"48","author":"Barker","year":"2017","journal-title":"Vet. Res."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1016\/j.virusres.2011.12.020","article-title":"Feline infectious peritonitis: Role of the feline coronavirus 3c gene in intestinal tropism and pathogenicity based upon isolates from resident and adopted shelter cats","volume":"165","author":"Pedersen","year":"2012","journal-title":"Virus Res."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"20022","DOI":"10.1038\/srep20022","article-title":"Experimental feline enteric coronavirus infection reveals an aberrant infection pattern and shedding of mutants with impaired infectivity in enterocyte cultures","volume":"6","author":"Desmarets","year":"2016","journal-title":"Sci. Rep."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"2735","DOI":"10.1099\/vir.0.19129-0","article-title":"Persistence and transmission of natural type I feline coronavirus infection","volume":"84","author":"Addie","year":"2003","journal-title":"J. Gen. Virol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1051\/vetres\/2010043","article-title":"Pathogenic characteristics of persistent feline enteric coronavirus infection in cats","volume":"41","author":"Vogel","year":"2010","journal-title":"Vet. Res."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"157","DOI":"10.1016\/j.vetmic.2014.10.025","article-title":"Levels of feline infectious peritonitis virus in blood, effusions, and various tissues and the role of lymphopenia in disease outcome following experimental infection","volume":"175","author":"Pedersen","year":"2015","journal-title":"Vet. Microbiol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1407","DOI":"10.1128\/jvi.64.3.1407-1409.1990","article-title":"Early death after feline infectious peritonitis virus challenge due to recombinant vaccinia virus immunization","volume":"64","author":"Vennema","year":"1990","journal-title":"J. Virol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1315","DOI":"10.1292\/jvms.70.1315","article-title":"Antibody-dependent enhancement occurs upon re-infection with the identical serotype virus in feline infectious peritonitis virus infection","volume":"70","author":"Takano","year":"2008","journal-title":"J. Vet. Med. Sci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1016\/0147-9571(81)90003-5","article-title":"Antibody-mediated enhancement of disease in feline infectious peritonitis: Comparisons with dengue hemorrhagic fever","volume":"4","author":"Weiss","year":"1981","journal-title":"Comp. Immunol. Microbiol. Infect. Dis."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1292\/jvms.60.49","article-title":"Antibody-dependent enhancement of feline infectious peritonitis virus infection in feline alveolar macrophages and human monocyte cell line U937 by serum of cats experimentally or naturally infected with feline coronavirus","volume":"60","author":"Hohdatsu","year":"1998","journal-title":"J. Vet. Med Sci."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1016\/j.vetmic.2006.11.026","article-title":"Absence of surface expression of feline infectious peritonitis virus (FIPV) antigens on infected cells isolated from cats with FIP","volume":"121","author":"Cornelissen","year":"2007","journal-title":"Vet. Microbiol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1136\/vr.130.7.133","article-title":"A study of naturally occurring feline coronavirus infections in kittens","volume":"130","author":"Addie","year":"1992","journal-title":"Vet. Rec."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"649","DOI":"10.1136\/vr.148.21.649","article-title":"Use of a reverse-transcriptase polymerase chain reaction for monitoring the shedding of feline coronavirus by healthy cats","volume":"148","author":"Addie","year":"2001","journal-title":"Vet. Rec."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1307","DOI":"10.2460\/javma.1997.210.09.1307","article-title":"Patterns of feline coronavirus infection and fecal shedding from cats in multiple-cat environments","volume":"210","author":"Foley","year":"1997","journal-title":"J. Am. Vet. Med. Assoc."},{"key":"ref_33","first-page":"92","article-title":"Control of feline coronavirus infections in breeding catteries by serotesting, isolation, and early weaning","volume":"23","author":"Addie","year":"1995","journal-title":"Feline Pract."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"948","DOI":"10.2460\/javma.1999.215.07.948","article-title":"Fecal shedding of feline coronavirus in adult cats and kittens in an Abyssinian cattery","volume":"215","author":"Harpold","year":"1999","journal-title":"J. Am. Vet. Med. Assoc."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"202","DOI":"10.1136\/vr.131.9.202-a","article-title":"Feline coronavirus antibodies in cats","volume":"131","author":"Addie","year":"1992","journal-title":"Vet. Rec."},{"key":"ref_36","unstructured":"Rohner-M\u00e4chler, M. (1999). Bestimmung der Ausscheidungskinetik von Felinen Coronaviren unter Feldbedingungen. Inaugural-Dissertation, University of Zurich."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"226","DOI":"10.1016\/j.vetmic.2018.04.026","article-title":"The nucleoside analog GS-441524 strongly inhibits feline infectious peritonitis (FIP) virus in tissue culture and experimental cat infection studies","volume":"219","author":"Murphy","year":"2018","journal-title":"Vet. Microbiol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1177\/1098612X19825701","article-title":"Efficacy and safety of the nucleoside analog GS-441524 for treatment of cats with naturally occurring feline infectious peritonitis","volume":"21","author":"Pedersen","year":"2019","journal-title":"J. Feline Med. Surg."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"222","DOI":"10.1016\/j.rvsc.2020.02.012","article-title":"Oral Mutian\u00aeX stopped faecal feline coronavirus shedding by naturally infected cats","volume":"130","author":"Addie","year":"2020","journal-title":"Res. Vet. Sci."},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Dickinson, P.J., Bannasch, M., Thomasy, S.M., Murthy, V.D., Vernau, K.M., Liepnieks, M., Montgomery, E., Knickelbein, K.E., Murphy, B., and Pedersen, N.C. (2020). Antiviral treatment using the adenosine nucleoside analogue GS-441524 in cats with clinically diagnosed neurological feline infectious peritonitis. J. Vet. Intern. Med.","DOI":"10.1111\/jvim.15780"},{"key":"ref_41","unstructured":"Addie, D.D., Bel\u00e1k, S., Boucraut-Baralon, C., Egberink, H., Frymus, T., Gruffydd-Jones, T., Hartmann, K., Hofmann-Lehmann, R., Hosie, M.J., and Lloret, A. (2020, March 26). Feline Infectious Peritonitis. Available online: http:\/\/www.abcdcatsvets.org\/feline-infectious-peritonitis\/."},{"key":"ref_42","first-page":"96","article-title":"Elimination of feline coronavirus infection from a large experimental specific pathogen-free cat breeding colony by serologic testing and isolation","volume":"23","author":"Hickman","year":"1995","journal-title":"Feline Pract."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1177\/1098612X11429644","article-title":"Quarantine protects Falkland Islands (Malvinas) cats from feline coronavirus infection","volume":"14","author":"Addie","year":"2012","journal-title":"J. Feline Med. Surg."},{"key":"ref_44","first-page":"27","article-title":"The epidemiology of feline infectious peritonitis in catteries","volume":"23","author":"Kass","year":"1995","journal-title":"Feline Pract."},{"key":"ref_45","first-page":"164","article-title":"Control of feline coronavirus infection in kittens","volume":"126","author":"Addie","year":"1990","journal-title":"Vet. Rec."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1016\/j.jfms.2003.12.009","article-title":"Recommendations from workshops of the second international feline coronavirus\/feline infectious peritonitis symposium","volume":"6","author":"Addie","year":"2004","journal-title":"J. Feline Med. Surg."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"349","DOI":"10.1006\/viro.1997.8663","article-title":"Persistence and evolution of feline coronavirus in a closed cat-breeding colony","volume":"234","author":"Herrewegh","year":"1997","journal-title":"Virology"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/S0166-0934(98)00129-3","article-title":"One-tube fluorogenic reverse transcription-polymerase chain reaction for the quantitation of feline coronaviruses","volume":"77","author":"Gut","year":"1999","journal-title":"J. Virol. Methods"},{"key":"ref_49","first-page":"406","article-title":"On the serological diagnosis of feline infectious peritonitis","volume":"65","author":"Lutz","year":"1984","journal-title":"Prakt. Tierarzt"},{"key":"ref_50","first-page":"835","article-title":"Seroepidemiology of feline infectious peritonitis virus-infections using transmissible gastroenteritis virus as antigen","volume":"24","author":"Osterhaus","year":"1977","journal-title":"Zent. Vet. Reihe B"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"1838","DOI":"10.1016\/j.vaccine.2005.10.030","article-title":"Antibody induction after combined application of an adjuvanted recombinant FeLV vaccine and a multivalent modified live virus vaccine with a chlamydial component","volume":"24","author":"Brunner","year":"2006","journal-title":"Vaccine"}],"container-title":["Pathogens"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-0817\/9\/8\/598\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T09:50:37Z","timestamp":1760176237000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-0817\/9\/8\/598"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,7,22]]},"references-count":51,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2020,8]]}},"alternative-id":["pathogens9080598"],"URL":"https:\/\/doi.org\/10.3390\/pathogens9080598","relation":{},"ISSN":["2076-0817"],"issn-type":[{"value":"2076-0817","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,7,22]]}}}