Abstract

COVID-19 is a zoonotic disease caused by SARS-CoV-2. Infections of animals with SARS-CoV-2 have recently been reported, and an increase of severe lung pathologies in domestic dogs has also been detected by veterinarians in Spain. Therefore, further descriptions of the pathological processes in those animals that show symptoms similar to those described in humans afected by COVID-19 would be highly valuable. The potential for companion animals to contribute to the continued transmission and community spread of this known human-to-human disease is an urgent issue to be considered. Forty animals with pulmonary pathologies were studied by chest X-ray, ultrasound analysis, and computed tomography. Nasopharyngeal and rectal swabs were analyzed to detect canine pathogens, including SARS-CoV-2. An additional twenty healthy dogs living in SARS-CoV-2-positive households were included. Immunoglobulin detection by several immunoassays was performed. Our fndings show that sick dogs presented severe alveolar or interstitial patterns with pulmonary opacity, parenchymal abnormalities, and bilateral lesions. The forty sick dogs were negative for SARS-CoV-2 but Mycoplasma spp. was detected in 26 of 33 dogs. Five healthy and one pathological dog presented IgG against SARS-CoV-2. Here we report that despite detecting dogs with α-SARS-CoV-2 IgG, we never obtained a positive RT-qPCR for SARS-SoV-2, not even in dogs with severe pulmonary disease suggesting that even in the case of canine infection, transmission would be unlikely. Moreover, dogs living in COVID-19-positive households could have been more highly exposed to infection with SARS-CoV 2.

Introduction

The year 2020 has seen an international health emergency generated by the emerging zoonotic coronavirus

SARS-CoV-2, which began its expansion in the end of the 2019 in Wuhan (China) and caused a pandemic within a few months [1, 2]. SARS-CoV-2 infection can lead to COVID-19, a pathology with various clinical manifestations, and in its severest form is mainly associated with lung injury and pathology similar to macrophage activation syndrome, such as hyperinfammation and lung damage by an uncontrolled activation and proliferation of T lymphocytes and macrophages [3, 4].

Four genera of coronaviruses have been described:

Alphacoronavirus, Betacoronavirus, Gammacoronavirus and Deltacoronavirus (α-CoV, β-CoV, γ-CoV and δ-CoV) according to their genetic structure. α-CoV and β-CoV infect mammals, and in addition to humans, have been also described in dogs and cats. Mostly, they Keywords: SARS-CoV-2, Dogs, Mycoplasma, Antibody, Pneumonia