A Large-Scale Serological Survey in Pets From October 2020 Through June 2021 in France Shows Significantly Higher Exposure to SARS-CoV-2 in Cats Compared to Dogs.

Matthieu Fritz1 Eric Elguero1 Pierre Becquart1 Daphné De Riols de Fonclare1 Déborah Garcia1 Stephanie Beurlet2 Solène Denolly3 Bertrand Boson3 Serge G Rosolen4,5 François-Loïc Cosset3 Alexandra Briend-Marchal2 Vincent Legros3,6 Eric M Leroy1
Affiliations 6 institutions
  1. Maladies Infectieuses et Vecteurs, Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Univ. Montpellier, IRD, CNRS, Montpellier, France.
  2. Laboratoire de Biologie vétérinaire VEBIO, Arcueil, France.
  3. CIRI - Centre International de Recherche en Infectiologie, Team EVIR, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, Lyon, France.
  4. Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.
  5. Clinique vétérinaire Voltaire, Asnières, France.
  6. Université de Lyon, VetAgro Sup, Campus vétérinaire de Lyon, Marcy-l'Etoile, Lyon, France.

Abstract

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has the potential to infect various animals, including domestic pets like dogs and cats. Many studies have documented infection in companion animals by molecular and serological methods. However, only a few have compared seroprevalence in cats and dogs from the general population, and these studies were limited by small sample sizes and collections over short periods. Our aim was to obtain a more accurate evaluation of seroprevalence in companion animals in France and to determine whether cats and dogs differ in their exposure to SARS-CoV-2. We conducted an extensive serological survey of SARS-CoV-2, collecting blood samples from 2036 cats and 3577 dogs during routine veterinary medical examinations across different regions of metropolitan France from October 2020 to June 2021. This period encompassed the peaks and onset of two waves, as well as the emergence of the first variants. A microsphere immunoassay targeting the receptor-binding domain and trimeric spike protein was used to detect anti-SARS-CoV-2 antibodies. A subset of 308 seropositive samples was tested for the presence of neutralising antibodies. We determined an overall seroprevalence of anti-SARS-CoV-2 antibodies of 7.1% (95% confidence interval [CI]: 6.4%-7.8%) among the sampled pets. Cats exhibited a significantly higher seroprevalence (9.3%; 95% CI: 8.1%-10.1%) compared to dogs (5.9%; 95% CI: 5.2%-6.8%). Among the subset of seropositive samples, 81 (26.3%; 95% CI: 21.5%-31.6%) displayed neutralizing antibodies. Furthermore, seroprevalence in both species was lower in older animals and was not associated with sex. Finally, unlike cats, seroprevalence in dogs was found to be correlated with the date of sampling. The large sample size enhances the reliability and statistical robustness of our estimates regarding pet exposure to SARS-CoV-2. This study on SARS-CoV-2 reaffirms the crucial importance of adopting a One Health approach incorporating domestic animals when managing an epidemic caused by a zoonotic virus.

Supporting text Virus Host Location
microsphere immunoassay 1 neutralisation assay 1 one health 98 pets 31 SARS‐CoV‐2 7 serology 50 Cat Diseases 67 COVID-19 425 Dog Diseases 65 Pets 25 SARS-CoV-2 453 Animals 1948 Antibodies, Viral 212 Cats 120 Dogs 176 Female 289 France 10 Male 224 Seroepidemiologic Studies 113

Evidence records

3 total
Zoonotic Surveillance
3 records · 1 evidence types
Evidence type
3 records
OVE8661
Key finding

An overall seroprevalence of anti‑SARS‑CoV‑2 antibodies of 7.1% was detected among cats and dogs sampled in France, indicating prior viral exposure in pets.

Virus
Host
Location
Not specified
Supporting text

We determined an overall seroprevalence of anti‑SARS‑CoV‑2 antibodies of 7.1% (95% confidence interval [CI]: 6.4%‑7.8%) among the sampled pets.

Method
microsphere immunoassay targeting receptor‑binding domain and trimeric spike protein
Sample type
blood samples | serum
OVE8662
Key finding

Cats showed a higher seroprevalence of anti‑SARS‑CoV‑2 antibodies (9.3%) compared with dogs (5.9%) across France, indicating a species‑related difference in exposure.

Virus
Host
Location
Not specified
Supporting text

Cats exhibited a significantly higher seroprevalence (9.3%; 95% CI: 8.1%‑10.1%) compared to dogs (5.9%; 95% CI: 5.2%‑6.8%).

Method
microsphere immunoassay targeting receptor‑binding domain and trimeric spike protein
Sample type
blood samples | serum
OVE8663
Key finding

Neutralizing antibodies against SARS‑CoV‑2 were detected in 26.3% of seropositive pet samples, confirming functional immune responses among exposed cats and dogs.

Virus
Host
Location
Not specified
Supporting text

Among the subset of seropositive samples, 81 (26.3%; 95% CI: 21.5%‑31.6%) displayed neutralizing antibodies.

Method
neutralization assay
Sample type
serum