{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,8]],"date-time":"2026-03-08T10:42:08Z","timestamp":1772966528717,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,4,3]],"date-time":"2021-04-03T00:00:00Z","timestamp":1617408000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Cats are susceptible to infection with severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2). Whilst a number of studies have been performed worldwide on owned cats, limited data are available on stray, colony or shelter cats. We investigated SARS-CoV-2 infection in a stray cat population before and during human outbreaks of SARS-CoV-2 in cities in the Lombardy region in northern Italy, a high endemic region for SARS-CoV-2, using serological and molecular methods. A cohort of different samples were collected from 241 cats, including frozen archived serum samples from 136 cats collected before the 2019 coronavirus disease (COVID-19) pandemic and serum, pharyngeal and rectal swab samples from 105 cats collected during the SARS-CoV-2 outbreak. All pre-pandemic samples tested seronegative for antibodies against the nucleocapsid of SARS-CoV-2 using indirect enzyme linked immunosorbent assay (ELISA) test, while one serum sample collected during the pandemic was seropositive. No serological cross-reactivity was detected between SARS-CoV-2 antibodies and antibodies against feline enteric (FECV) and infectious peritonitis coronavirus (FIPC), Feline Immunodeficiency Virus (FIV), Feline Calicivirus (FCV), Feline Herpesvirus-1 (FHV-1), Feline Parvovirus (FPV), Leishmania infantum, Anaplasma phagocytophilum, Rickettsia spp., Toxoplasma gondii or Chlamydophila felis. No pharyngeal or rectal swab tested positive for SARS-CoV-2 RNA on real time reverse transcription-polymerase chain reaction (rRT-PCR). Our data show that SARS-CoV-2 did infect stray cats in Lombardy during the COVID-19 pandemic, but with lower prevalence than found in owned cats. This should alleviate public concerns about stray cats acting as SARS-CoV-2 carriers.<\/jats:p>","DOI":"10.3390\/v13040618","type":"journal-article","created":{"date-parts":[[2021,4,3]],"date-time":"2021-04-03T22:03:36Z","timestamp":1617487416000},"page":"618","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":43,"title":["A pre- and during Pandemic Survey of Sars-Cov-2 Infection in Stray Colony and Shelter Cats from a High Endemic Area of Northern Italy"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3898-6955","authenticated-orcid":false,"given":"Eva","family":"Spada","sequence":"first","affiliation":[{"name":"Laboratorio di Ricerca di Medicina Emotrasfusionale Veterinaria (REvLab), Dipartimento di Medicina Veterinaria (DIMEVET), Universit\u00e0 degli Studi di Milano, 26900 Lodi, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fabrizio","family":"Vitale","sequence":"additional","affiliation":[{"name":"Centro di Referenza Nazionale per le Leishmaniosi (C.Re.Na.L), Istituto Zooprofilattico Sperimentale (IZS) della Sicilia A. Mirri, 90129 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6181-6984","authenticated-orcid":false,"given":"Federica","family":"Bruno","sequence":"additional","affiliation":[{"name":"Centro di Referenza Nazionale per le Leishmaniosi (C.Re.Na.L), Istituto Zooprofilattico Sperimentale (IZS) della Sicilia A. Mirri, 90129 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0464-4474","authenticated-orcid":false,"given":"Germano","family":"Castelli","sequence":"additional","affiliation":[{"name":"Centro di Referenza Nazionale per le Leishmaniosi (C.Re.Na.L), Istituto Zooprofilattico Sperimentale (IZS) della Sicilia A. Mirri, 90129 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stefano","family":"Reale","sequence":"additional","affiliation":[{"name":"Centro di Referenza Nazionale per le Leishmaniosi (C.Re.Na.L), Istituto Zooprofilattico Sperimentale (IZS) della Sicilia A. Mirri, 90129 Palermo, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8241-907X","authenticated-orcid":false,"given":"Roberta","family":"Perego","sequence":"additional","affiliation":[{"name":"Laboratorio di Ricerca di Medicina Emotrasfusionale Veterinaria (REvLab), Dipartimento di Medicina Veterinaria (DIMEVET), Universit\u00e0 degli Studi di Milano, 26900 Lodi, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Luciana","family":"Baggiani","sequence":"additional","affiliation":[{"name":"Laboratorio di Ricerca di Medicina Emotrasfusionale Veterinaria (REvLab), Dipartimento di Medicina Veterinaria (DIMEVET), Universit\u00e0 degli Studi di Milano, 26900 Lodi, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3922-6069","authenticated-orcid":false,"given":"Daniela","family":"Proverbio","sequence":"additional","affiliation":[{"name":"Laboratorio di Ricerca di Medicina Emotrasfusionale Veterinaria (REvLab), Dipartimento di Medicina Veterinaria (DIMEVET), Universit\u00e0 degli Studi di Milano, 26900 Lodi, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,3]]},"reference":[{"key":"ref_1","unstructured":"(2020, March 18). 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